<PAGE>

                                     LEASE

                            200 SOUTH WACKER DRIVE

                               CHICAGO, ILLINOIS

                              TENFOLD CORPORATION
<PAGE>

                               TABLE OF CONTENTS
                               -----------------

<TABLE>
<CAPTION>
                                                                         Page
                                                                         ----
<S>                                                                      <C>
1.  TERM..................................................................  1

2.  BASE RENT.............................................................  2

 A.  Base Rent............................................................  2
 B.  Abatement of Initial Base Rent.......................................  2

3.  ADDITIONAL RENT.......................................................  2

 A.  Definitions..........................................................  3
 B.  Expense Adjustment...................................................  6
 C.  Tax Adjustment.......................................................  6
 D.  Allocation of Operating Expenses.....................................  7
 E.  Tenant's Right to Examine Landlord's Books and Records...............  7

4.  USE OF THE PREMISES...................................................  8

 A.  Reserved Areas.......................................................  8
 B.  Permitted Use........................................................  9
 C.  Compliance with Law..................................................  9
 D.  Hazardous Materials..................................................  9

5.  POSSESSION............................................................ 10

6.  SERVICES.............................................................. 11

 A.  List of Services..................................................... 11
 B.  Billing for Electricity.............................................. 13
 C.  Interruption of Services............................................. 13
 D.  Charges for Services................................................. 13
 E.  Energy Conservation.................................................. 14

7.  REPAIRS............................................................... 14

8.  ADDITIONAL AND ALTERNATIONS........................................... 15
</TABLE>

                                       i
<PAGE>

<TABLE>
<S>                                                                        <C>
9.  CONVENANT AGAINST LIENS..............................................  15

10.  INSURANCE...........................................................  16

  A.  Waiver of Subrogation..............................................  16
  B.  Coverage...........................................................  16
  C.  Avoid Action Increasing Rates......................................  17
  D.  Landlord's Insurance...............................................  17

11.  FIRE OR CASUALTY....................................................  17

12.  WAIVER OF CLAIMS - INDEMNIFICATION..................................  18

13.  NONWAIVER...........................................................  19

14.  CONDEMNATION........................................................  19

15.  ASSIGNMENT AND SUBLETTING...........................................  20

16.  SURRENDER OF POSSESSION.............................................  24

17.  HOLDING OVER........................................................  25

18.  ESTOPPEL CERTIFICATE................................................  25

19.  OBLIGATION TO MORTGAGEES............................................  26

  A.  Subordination......................................................  26
  B.  Notice to Landlord and Mortgagee...................................  26
  C.  Non-Disturbance Agreement..........................................  26

20.  CERTAIN RIGHTS RESERVED BY LANDLORD.................................  26

21.  RULES AND REGULATIONS...............................................  28

22.  LANDLORD'S REMEDIES.................................................  28

23.  EXPENSES OF ENFORCEMENT.............................................  30

24.  COVENANT OF QUIET ENJOYMENT.........................................  30
</TABLE>

                                      ii
<PAGE>

<TABLE>
<S>                                                                      <C>
25.  LETTER OF CREDIT..................................................  30

26.  REAL ESTATE BROKER................................................  32

27.  MISCELLANEOUS.....................................................  32

  A.  Rights Cumulative................................................  32
  B.  Interest.........................................................  33
  C.  Terms............................................................  33
  D.  Binding Effect...................................................  33
  E.  Lease Contains All terms.........................................  33
  F.  Delivery for Examination.........................................  33
  G.  No Air Rights....................................................  33
  H.  Modification of Lease............................................  33
  I.  [Intentionally Omitted]..........................................  33
  J.  Transfer of Landlord's Interest..................................  33
  K.  Landlord's Title.................................................  34
  L.  Prohibition Against Recording....................................  34
  M.  Captions.........................................................  34
  N.  Covenants and Conditions.........................................  34
  O.  Only Landlord/Tenant Relationships...............................  34
  P.  Application of Payments..........................................  34
  Q.  Definition of Landlord...........................................  34
  R.  Time of Essence..................................................  34
  S.  Time for Performance.............................................  34
  T.  Governing Law....................................................  35
  U.  Partial Invalidity...............................................  35
  V.  Parking..........................................................  34

28.  NOTICES...........................................................  35

29.  LIMITATION ON LANDLORD'S LIABILITY................................  36

30.  TENANT ALLOWANCES.................................................  36
</TABLE>

                                      iii
<PAGE>

<TABLE>
<S>                                                                      <C>
31.  RIGHT OF FIRST OFFER..............................................  37

32.  OPTION TO EXTEND..................................................  38

33.  ROOF RIGHTS.......................................................  39
</TABLE>

                                      iv
<PAGE>

                                     LEASE
                            200 SOUTH WACKER DRIVE
                               CHICAGO, ILLINOIS


     AGREEMENT OF LEASE made as of this 20th day of June, 2000 (hereinafter
referred to as the "Lease") between 200 South Wacker Drive, L.L.C., an Illinois
limited liability company (hereinafter referred to as "Landlord"), and TenFold
Corporation, a Delaware corporation (hereinafter referred to as "Tenant");

                                  WITNESSETH:

Landlord hereby agrees to Lease to Tenant, and Tenant hereby agrees to accept,
(a) that certain space commonly described as the entirety of the fifteenth
(15/th/) floor and containing approximately 21,897 square feet of "Rentable
Area" ("Area A"), and (b) that certain space commonly described as the entirety
of the fourteenth (14/th/) and sixteenth (16/th/) floors and containing
approximately 43,777 square feet of Rentable Area in the aggregate ("Area B")
(Area A and Area B contain in the aggregate approximately 65,674 square feet of
"Rentable Area" and are separately and together referred to as the "Premises"
and are designated on the plan attached hereto as Exhibit A) in the building
known as 200 South Wacker Drive (hereinafter referred to as the "Building")
located on a parcel of land at the southwest corner of South Wacker Drive and
West Adams Street, in the City of Chicago, Cook County, Illinois (hereinafter
referred to, together with all present and future easements, additions,
improvements and other rights appurtenant thereto, as the "Land", which Land is
legally described on Exhibit I attached hereto and made a part hereof), subject
to the terms and conditions of this Lease. For purposes of this Lease, the
Rentable Area of the Building and the Premises shall be computed in accordance
with Building Owners and Managers Association International Standard Method for
Measuring Floor Area in Office Buildings known as ANSI/BOMA Z65.1-1996, approved
June 7, 1996 by American National Standards Institute, Inc. ("BOMA Standards"),
as modified in a manner similar to that adopted by other similar class office
buildings in the Chicago metropolitan area and consistently applied throughout
the Building.

     In consideration thereof, Landlord and Tenant covenant and agree as
follows:

     1.   TERM.
          ----

          The term of this Lease (hereinafter referred to as the "Term") shall
commence, as to Area A, on October 1, 2000 (the "Area A Commencement Date"), and
as to Area B, on October 1, 2001 (the "Area B Commencement Date"), and shall end
on the last day of the seventy-second (72/nd/) full calendar month following the
Area B Commencement  Date (hereinafter referred to as the "Termination Date"),
unless sooner terminated (or extended) as provided herein.  The Area A
Commencement Date and the Area B Commencement  Date shall be deferred in
accordance with Paragraph 5 hereof.  In no event shall it be a default under
this
<PAGE>

Lease if Tenant shall fail to occupy either Area A or Area B on the Area A
Commencement Date or Area B Commencement Date, as the case may be; provided that
all of Tenant's other obligations under this Lease with respect to Area A and
Area B shall commence on the respective Commencement Date, subject to Section
2.B hereof. Landlord and Tenant shall confirm by written memorandum (the "Term
Commencement Memorandum") the Area A Commencement Date, the Area B Commencement
Date and the Termination Date promptly following the establishment of the such
dates. The Term Commencement Memorandum shall be in the form attached hereto as
Exhibit J.

     2.   BASE RENT.
          ---------

          A.   Base Rent.  Tenant shall pay to Landlord or Landlord's agent at
               ---------
200 South Wacker Drive, Chicago, Illinois, or at such other place as Landlord
may from time to time designate in writing, in currency which, at the time of
payment, is legal tender for private or public debts in the United States of
America, rent at the annual rate set forth in the schedule attached hereto as
Exhibit B and made a part hereof (hereinafter referred to as the "Base Rent") on
or before the first day of each and every month during the Term, without demand
and without any set-off or deduction whatsoever. Tenant shall pay the first full
monthly installment of Base Rent at the time of execution of this Lease. Any
Base Rent payable for a partial month shall be paid on a pro rata basis based on
the number of days in such partial month on the first day of such month which
falls within the Term. Each period of twelve (12) months beginning on the Area A
Commencement Date or on any anniversary thereof and ending on the day before the
following anniversary of the Area A Commencement Date or on the Termination
Date, as the case may be, is hereinafter referred to as a "Lease Year."

          B.   Abatement of Initial Base Rent.  If Tenant has taken occupancy of
               ------------------------------
the portion of Area B comprising the entirety of the sixteenth (16/th/) floor
for the purpose of carrying on its business therein and if Tenant is not in
default under this Lease (beyond any applicable cure period) on the date any
such installment is due, each of the first nine (9) monthly installments of Base
Rent due hereunder with respect thereto and commencing on the Area B
Commencement Date (i.e., $34,643.33 per month) shall be abated in full and shall
not be payable by Tenant, subject to the terms of Section 22 hereof.

     3.   ADDITIONAL RENT.
          ---------------

          In addition to paying the Base Rent specified in Section 2 hereof,
Tenant shall pay as "Additional Rent" the amounts described in this Section 3.
Such Additional Rent paid by Tenant and other tenants in the Building shall
reimburse Landlord for all expenses of owning, operating and maintaining the
Land and the Building, except as expressly excluded below, and shall permit
Landlord to receive the Base Rent as "net" rent. The Base Rent and the
Additional Rent are sometimes herein collectively referred to as the "Rent." All
Additional Rent shall be payable for the same periods and in the same manner,
time and place as the Base Rent. Without limitation on other obligations of
Tenant which shall survive the expiration of the Term, the obligations of Tenant
to pay Additional Rent shall survive the expiration of the Term. For any partial
Calendar Year, Tenant shall be obligated to pay only a pro rata share of the
Additional

                                       2
<PAGE>

Rent for such Calendar Year, based on the number of days of the Term falling
within such Calendar Year.

          A.    Definitions.  As used in this Section 3, the terms:
                -----------

          (i)   "Calendar Year" shall mean each calendar year in which any part
of the Term falls, through and including the year in which the Term expires.

          (ii)  "Tenant's Proportionate Share" shall mean the percentage
calculated by dividing the Rentable Area contained in the Premises, as
determined by Landlord and shown on the first page of this Lease, by 756,600
rentable square feet (being the Rentable Area of the Building).  Tenant's
Proportionate Share is agreed to be 2.894% for the first Lease Year, and 8.680%
for the remainder of the Term thereafter.

          (iii) "Taxes" shall mean taxes levied, assessed or imposed against
Landlord (or which Landlord is obligated to pay on behalf of any other person or
entity having any interest in the Land or the Building) in connection with the
Land, the Building, the operation thereof or any rights or responsibilities
related thereto. "Taxes" shall include without limitation: (a) real estate taxes
and assessments, special or otherwise, levied or assessed upon the Land or
Building; (b) ad valorem taxes for any personal property used in connection with
the Land or Building; (c) any tax, assessment, charge or fee which is imposed in
substitution for, or in lieu of an increase in, such real estate taxes and ad
valorem personal property taxes; (d) any income or franchise tax based on
Landlord's income from the Land and Building which taxes such income in a
different manner than income from sources other than the ownership and operation
of income-producing real estate; or (e) a tax on rents or leases. Taxes shall
also include, in the year paid, all reasonable fees for consultants and
attorneys and all other reasonable costs incurred by Landlord in seeking to
obtain a reduction of, or a limit on the increase in, any Taxes, regardless of
whether any reduction or limitation is obtained. Taxes shall not include any
inheritance, estate, succession, transfer, gift, franchise, or capital stock tax
or any income taxes other than those described above.

          (iv)  "Operating Expenses" shall mean all expenses, costs and
disbursements (other than Taxes) of every kind and nature (determined for the
applicable Calendar Year on an accrual basis) paid or incurred by Landlord in
connection with the ownership, management, operation, maintenance and repair of
the Land and Building, except the following:

          a.    Costs of capital improvements to any tenant's premises;

          b.    Principal or interest payments on loans secured by mortgages or
     trust deeds on the Building or Land or rent payable on any ground lease of
     the Land;

          c.    Costs of capital improvements to the Building (including any
     improvements required to the common areas of the Building in order to
     comply with the provisions of the Americans With Disabilities Act of 1990
     (42 U.S.C. (S)12-101 et seq.) (the "ADA")), except that Operating Expenses
     shall include (a) the cost of any capital improvement completed on or after
     the Area A Commencement Date, a material purpose

                                       3
<PAGE>

     of which is to reduce any component of Operating Expenses, as evenly
     amortized over the useful life of each such capital improvement with
     interest on the unamortized amount at the greater of (i) 12% per annum or
     (ii) 2% per annum above the prime rate or base rate or other comparable
     reference rate of interest announced from time to time by Bank One, N.A. or
     other bank designated by Landlord if Bank One is not at any time announcing
     a prime rate or base rate or other comparable reference rate (but in no
     event at a rate which is more than the highest lawful rate allowable in the
     State of Illinois); and (b) the cost of any capital improvement (other than
     an improvement required in order for the Building to comply with the ADA)
     which is made by Landlord to keep the Land or Building in compliance with
     all governmental rules and regulations applicable from time to time thereto
     after the Area A Commencement Date;

          d.   Real estate brokers' leasing commissions and attorneys' fees and
     expenses incurred in negotiating leases for space in the Building or
     handling disputes with tenants of the Building;

          e.   The cost of repairing, replacing or restoring any portion of the
     Building damaged by a casualty, except that Operating Expenses shall
     include the costs of repairs or other work occasioned by a casualty to the
     extent that such cost is not covered by Landlord's insurance described in
     Section 11 hereof because of any deductible amount;

          f.   The cost of repairs, alterations or replacements required as the
     result of the exercise of any right of eminent domain, to the extent
     Landlord has received an award therefor;

          g.   Advertising, marketing and promotional expenses incurred in
     connection with leasing space in the Building or marketing of the Building;

          h.   Court costs and legal fees incurred in connection with disputes
     with any tenant (exclusive of any legal fees or other costs incurred by
     Landlord in an action to enforce any tenant's compliance with the rules and
     regulations of the Building, and provided that the foregoing shall not
     affect Landlord's rights to recover attorneys' fees in any dispute with
     Tenant pursuant to Section 23 hereof);

          i.   any compensation paid to clerks, attendants or other persons in
     commercial concessions operated by Landlord, if any;

          j.   Costs to initially comply with governmental rules and regulations
     in effect as of the date of this Lease, to the extent the Building is not
     in compliance with such rules or regulations as of such date;

          k.   Costs, other than costs to maintain and insure, of paintings,
     sculptures and other artwork within the Building;

                                       4
<PAGE>

          l.   Wages, salaries or other compensation and benefits of any off-
     site personnel, except for the pro rata portion of such wages, salaries,
     compensation and benefits of such off-site personnel (including those above
     the level of property manager) attributable to time actually spent by such
     personnel directly in connection with the management or operation of the
     Building;

          m.   Costs of extraordinary services or work which are not uniformly
     furnished or generally available to tenants of the Building and Tenant or
     services or work which are uniformly furnished or generally available but
     only at additional cost to the tenant or services or work provided to any
     tenant to a materially greater extent than provided to Tenant (such as
     charges for after hours heating or air conditioning, supplemental chilled
     water charges, and loading dock services);

          n.   Franchise, income, inheritance or transfer taxes imposed on
     Landlord (except to the extent such items are payable by Tenant as Taxes
     pursuant to clause (iii) of this Section 3.A);

          o.   Costs of buildout, alterations, renovation or decoration of
     tenant spaces;

          p.   Legal expenses, accounting and other professional services costs
     not allocable to operation or management of the Building;

          q.   Repairs necessitated by the negligence or intentional misconduct
     of Landlord, its agents, employees and servants;

          r.   Costs of management fees in excess of the prevailing market fees
     (as such prevailing market fees may change from time to time) charged in
     similar sized and class office buildings in the downtown Chicago area;

          s.   Charitable or political contributions;

          t.   Costs and expenses incurred to test, survey, clean up, remove or
     otherwise remedy Hazardous Materials (as defined in Section 4.D. hereof),
     or otherwise related to the testing, surveying, clean up or removal thereof
     or otherwise to comply with any environmental laws in effect as of the Area
     A Commencement Date with respect to the Building or the Land;

          u.   Payments of any other cost or expense to the extent to which
     Landlord is paid or reimbursed by any person (whether an insurer,
     condemnor, tenant, warrantor or otherwise) to the extent Landlord actually
     receives payment or reimbursement;

          v.   All salaries and expenses for any of Landlord's employees above
     the level of property manager;

                                       5
<PAGE>

          w.   The cost of any special service or benefit rendered to a tenant
     of the Building which is not rendered generally to tenants of the Building;

          x.   Depreciation or amortization of any improvements except as
     specifically set forth in this Lease; and

          y.   Costs (including, without limitation, attorneys' fees), fines or
     penalties incurred due to the violation by Landlord of applicable laws and
     regulations or due to the late payment of taxes, utility bills and other
     costs incurred as a result of Landlord's failure to make such payments when
     due, so long as Tenant has been timely in the payment of bills to Landlord.

          B.   Expense Adjustment. Tenant shall pay to Landlord or Landlord's
               ------------------
agent as Additional Rent, an amount ("Expense Adjustment Amount") equal to
Tenant's Proportionate Share of the amount of Operating Expenses incurred with
respect to each Calendar Year plus Tenant's pro rata share of the special
allocation of Operating Expenses to occupied premises if Section 3D is
applicable for such Calendar Year. The Expense Adjustment Amount with respect to
each Calendar Year shall be paid in monthly installments during such Calendar
Year in an amount estimated from time to time by Landlord and communicated by
written notice to Tenant. Landlord shall cause to be kept books and records
showing Operating Expenses in accordance with an appropriate system of accounts
and accounting practices consistently maintained. Within three (3) months after
the close of each Calendar Year or as soon thereafter as is reasonably
practicable, Landlord shall cause the amount of the Expense Adjustment Amount
for such Calendar Year to be computed based on Operating Expenses for such
Calendar Year and shall deliver to Tenant a statement of such amount plus a
statement of all estimated installments paid by Tenant with respect to such
Calendar Year. Tenant shall pay to Landlord any deficiency shown by such
statement within thirty (30) days after receipt of such statement. If the
installments paid exceed the amount due, and if Tenant is not then in default
hereunder, Landlord shall either credit the excess against payments next due to
Landlord from Tenant hereunder or, at Landlord's option, refund the excess to
Tenant within thirty (30) days following Landlord's determination. Delay in
computation of the Expense Adjustment Amount shall not be deemed a default
hereunder or a waiver of Landlord's right to collect the Expense Adjustment
Amount.  In no event shall Landlord recover the cost of any item of Operating
Expenses more than once.

          C.   Tax Adjustment. Tenant shall pay to Landlord or Landlord's agent
               --------------
as Additional Rent, an amount ("Tax Adjustment Amount") equal to Tenant's
Proportionate Share of the amount of Taxes incurred with respect to each
Calendar Year. The Tax Adjustment Amount with respect to each Calendar Year
shall be paid in monthly installments during such Calendar Year in an amount
estimated from time to time by Landlord and communicated by written notice to
Tenant. If any portion of Taxes for any Calendar Year is payable in whole or in
part before the end of such Calendar Year, Tenant shall, within thirty (30) days
after the written request of Landlord, promptly pay its Proportionate Share of
such payment as a special installment, after deducting installments previously
paid by Tenant under this Section 3C for such Calendar Year. Following the final
payment of Taxes for each Calendar Year, Landlord shall cause the amount of the
Tax Adjustment Amount for such Calendar Year to be computed

                                       6
<PAGE>

and deliver to Tenant a statement of such amount plus a statement of all
estimated installments paid by Tenant for such Calendar Year. Tenant shall pay
to Landlord any deficiency shown by such statement within thirty (30) days after
receipt of such statement. If the installments paid exceed the actual amount
due, and if Tenant is not then in default hereunder, Landlord shall either
credit the excess against payments next due to Landlord from Tenant hereunder
or, at Landlord's option, refund the excess to Tenant within thirty (30) days
following Landlord's determination. The amount of any refund of Taxes received
by Landlord shall be credited against Taxes for the year in which such refund is
received. In determining the amount of Taxes for any year, the amount of special
assessments to be included shall be limited to the amount of the installment
(plus any interest payable thereon) of such special assessment required to be
paid during such year as if the Landlord had elected to have such special
assessment paid over the maximum period of time permitted by law. All references
to Taxes "for" a particular year shall be deemed to refer to Taxes assessed for
such year, notwithstanding that such Taxes are billed and paid in a subsequent
Calendar Year. Delay in computation of the Tax Adjustment Amount shall not be
deemed a default hereunder or a waiver of Landlord's right to collect the Tax
Adjustment Amount.

          D.   Allocation of Operating Expenses. If at any time during the Term
               --------------------------------
less than ninety-five percent (95%) of the then current Rentable Area of the
Building is occupied by tenants, at Landlord's option those components of
Operating Expenses which vary with occupancy shall be adjusted to reflect the
Operating Expenses as though the Building had been 95% occupied during such
period. Such adjustment shall be made on a pro rata basis over the occupied
Rentable Area of the Building, based on both the comparative Rentable Areas of
the occupied premises and the portion of such Calendar Year during which such
premises were occupied. Operating Expenses which do not vary with occupancy,
such as public liability insurance, lobby maintenance and heating and air
conditioning costs, will continue to be allocated on a pro rata basis over the
Rentable Area of the Building whether or not occupied and Tenant shall only be
responsible for its Proportionate Share of such Operating Expenses.

          E.   Tenant's Right to Examine Landlord's Books and Records. If Tenant
               ------------------------------------------------------
does not agree with or otherwise wishes to confirm the correctness of Landlord's
determination of Operating Expenses and Taxes for any Calendar Year, then Tenant
shall have the right to inspect such of Landlord's books and records relative
thereto during normal business hours and in the Office of the Building if
written request ("Tenant's Inspection Request") is given by Tenant to Landlord
not later than sixty (60) days following receipt of the statements described in
Sections 3B and 3C, as the case may be. Any photocopies of Landlord's books and
records which Tenant desires shall be coordinated by Landlord and shall be made
at Tenant's sole cost and expense. If the parties are unable by negotiation to
reach agreement with respect to Operating Expenses or Taxes for the Calendar
Year in question within sixty (60) days following Tenant's Inspection Request,
Tenant may cause a qualified independent certified public accountant designated
by Tenant from a list of not less than five (5) such accountants selected by
Landlord (to be paid on an hourly and not a contingent fee basis) to audit
Landlord's records with respect to Operating Expenses or Taxes. Upon designation
by Tenant of the accountant, all activities of the accountant in connection with
such audit shall be undertaken upon the express direction and authorization of
Tenant. In the event such audit discloses (i) errors made during the prior

                                       7
<PAGE>

Calendar Year which, when totaled, establish that the sum overcharged to and
paid by Tenant exceeds five percent (5%) of the actual (as distinguished from
estimated) amount of Tenant's Proportionate Share of Operating Expenses or
Taxes, as the case may be, the audit shall be at the expense of Landlord, or
(ii) no errors or an error which equals or is less than five percent (5%), the
audit shall be at the expense of Tenant.

     The results of the audit (regardless of the degree of the error, if any)
shall be binding upon Landlord and Tenant and Landlord shall thereafter, if
appropriate, change its method of calculating Operating Expenses and Taxes
consistent with the results of the audit. If no Tenant's Inspection Request is
received by Landlord within sixty (60) days following receipt by Tenant of
Landlord's statement, or if Tenant shall not elect to cause an audit to be made
of Landlord's records by delivering written notice to Landlord of Tenant's
exercise of Tenant's audit right within sixty (60) days after delivery of
Tenant's Inspection Request, then Landlord's statement shall conclusively be
deemed to have been approved and accepted by Tenant. Any amount shown by
Landlord's statement to be due to Landlord, whether or not Tenant's Inspection
Request is delivered to Landlord, shall be paid by Tenant as provided in
Sections 3B and 3C above, without prejudice to any such inspection request. If
Tenant timely delivers Tenant's Inspection Request, any charges disclosed by
such statement which Landlord agrees are irregular or improper or which are
thereafter determined to be in error shall be promptly corrected by Landlord,
and Tenant shall receive a credit against the next amounts of Additional Rent
due from Tenant, or Landlord shall pay promptly such amounts due to Tenant, if
such determination is made after the end of the Term, so long as Tenant is not
then in monetary or other material non-monetary default hereunder (subject,
however, to Landlord's right to offset such amount by any amounts owing from
Tenant to Landlord under this Lease) for any overpayments made by Tenant as a
result of such irregularities or improper charges, or Tenant shall promptly pay
to Landlord any amounts determined to be due Landlord, as the case may be.

          Tenant acknowledges and agrees that it is a condition of Tenant's
right to conduct any inspection or audit pursuant to the foregoing, that Tenant
prior to commencement of such inspection or audit shall execute a
confidentiality agreement whereby Tenant agrees to keep confidential and not
disclose to any other party the results of any such inspection or audit or any
action taken by Landlord in response thereto.

     4.   USE OF THE PREMISES.
          -------------------

          A.   Reserved Areas. This Lease does not give Tenant any right to use,
               --------------
and Landlord hereby excludes and reserves for its sole and exclusive use, the
following areas in and about the Premises: janitor closets, stairways and
stairwells (except that Tenant shall be permitted to use the Building stairwells
between floors of the Premises if Tenant installs, at Tenant's expense and with
Landlord's prior approval, a security access system to the Premises), fan,
mechanical, electrical, telephone and similar rooms (other than those installed
for Tenant's exclusive use); elevator, pipe and other vertical shafts, flues and
ducts; all areas above the acoustical ceiling and below the finished floor
covering installed in the Premises; all other structural or mechanical elements
serving other areas of the Building; and all subterranean, mineral, air, light
and view rights.

                                       8
<PAGE>

          B.   Permitted Use. Tenant shall use and occupy the Premises for any
               -------------
general office purpose and incidental related purposes, which shall include
software development, software demonstration and training, consistent with the
operation of a first-class office building in Chicago, Illinois.

          C.   Compliance with Laws. Tenant shall not use or permit the use of
               --------------------
any part of the Premises for any purpose prohibited by law. Tenant shall, at its
sole expense, comply with and conform to all of the requirements of all
governmental authorities having jurisdiction over the Building which relate in
any way to the condition, use and occupancy of the Premises throughout the
entire Term of this Lease.  Landlord shall operate the Building in compliance
with all applicable laws and requirements of all governmental authorities having
jurisdiction over the Building.

          D.   Hazardous Materials. Tenant agrees that it will not use, handle,
               -------------------
generate, treat, store or dispose of, or permit the handling, generation,
treatment, storage or disposal of any Hazardous Materials in, on, under, around
or above the Premises now or at any future time and will indemnify, defend and
save Landlord harmless from any and all actions, proceedings, claims, costs,
expenses and losses of any kind, including, but not limited to, those arising
from injury to any person, including death, damage to or loss of use or value of
real or personal property, and costs of investigation and cleanup in connection
with the introduction of Hazardous Materials on the Premises by Tenant, its
agents, employees, contractors, servants and invitees during the Term hereof.
The term "Hazardous Materials", when used herein, shall include, but shall not
be limited to, any substances, materials or wastes to the extent quantities
thereof are regulated by the City of Chicago or any other local governmental
authority, the State of Illinois, or the United States of America because of
toxic, flammable, explosive, corrosive, reactive, radioactive or other
properties that may be hazardous to human health or the environment, including
asbestos and including any materials or substances that are listed in the United
States Department of Transportation Hazardous Materials Table, as amended, 49
C.F.R. 172.101, or in the Comprehensive Environmental Response, Compensation and
Liability Act, as amended, 42 U.S.C. subsections 9601 et seq., or the Resource
Conservation and Recovery Act, as amended, 42 U.S.C. subsections 6901 et seq.,
or any other applicable governmental regulation imposing liability or standards
of conduct concerning any hazardous, toxic or dangerous substances, waste or
material, now or hereafter in effect.  Tenant's obligations and liabilities
under this paragraph shall survive the expiration of the Term of this Lease.

     Landlord agrees that it will not knowingly cause the storage or disposal of
any Hazardous Materials in the Building (except insubstantial amounts of
Hazardous Materials customarily used in connection with general office building
uses, provided such use and storage is in compliance with applicable laws), and
Landlord will promptly after discovery thereof cause any such materials to be
removed from the Building or otherwise contained within applicable government
requirements, in a manner such that the Building shall at all times comply with
any and all environmental laws, rules and regulations of any applicable
governmental authority. Landlord represents that to the best of its knowledge,
without any independent investigation or inquiry, the

                                       9
<PAGE>

Building does not contain any materials classified as Hazardous Materials,
except insubstantial amounts customarily used in connection with general office
building uses.

     5.   POSSESSION.
          ----------

          A.   Possession of Area A and Area B shall be tendered to Tenant by
Landlord on, respectively, the Area A Commencement Date and the Area B
Commencement Date if Landlord has substantially completed its express
obligations set forth in the Work Letter attached hereto as Exhibit C and made a
part hereof (the "Work Letter").  If Landlord is unable to complete
substantially such obligations by the Area A Commencement Date or the Area B
Commencement Date, as the case may be, or if Landlord is unable to tender
possession on such date by reason of the holding over or retention of possession
by any tenant or occupant, this Lease shall nevertheless continue in force and
effect, the Area A Commencement Date or the Area B Commencement Date, as the
case may be, shall be deferred (and Rent, as hereinabove defined shall abate)
until such obligations of Landlord are substantially completed or until the
Landlord is able to tender possession, as the case may be, and Landlord shall
have no other liability whatsoever on account of such delay, except as
hereinafter provided. However, there shall be no deferral of the Area A
Commencement Date or the Area B Commencement Date or any abatement of Rent to
the extent that Landlord's obligations are not substantially completed because
of any delays caused by Tenant as described in the Work Letter, and in such
event, the Area A Commencement Date or the Area B Commencement Date, as the case
may be, shall be deemed to be the date Landlord's obligations would have been
completed but for any such delays.  In addition to the deferral of the Area A
Commencement Date and the abatement of Rent with respect to Area A, if Landlord
has been unable to substantially complete its Work Letter obligations with
respect to Area A by October 1, 2000, and such delay has not been caused by
Tenant as described in the Work Letter, Tenant shall be entitled to an
additional one (1) day of Rent abatement for each one (1) day of such delay, not
to exceed, however, fourteen (14) days of such additional Rent abatement.

     Notwithstanding the foregoing, in the event Landlord has failed to
substantially complete its obligations set forth in the Work Letter with respect
to Area A by April 1, 2001 for any reason other than due to a delay caused by
Tenant as described in the Work Letter, Tenant shall have the option to
terminate this Lease upon delivery of written notice thereof to Landlord on or
before May 1, 2001, unless prior to receipt of notice of such termination,
Landlord has caused such obligations to be substantially completed. In addition,
in the event Landlord has failed to substantially complete its obligations set
forth in the Work Letter with respect to Area B by April 1, 2002 for any reason
other than due to a delay caused by Tenant as described in the Work Letter,
Tenant shall have the option to terminate this Lease as to Area B only (with a
pro rata adjustment in Tenant's rental obligations hereunder) upon delivery of
written notice thereof to Landlord on or before May 1, 2002, unless prior to
receipt of notice of such termination, Landlord has caused such obligations to
be substantially completed.

          B.   If Landlord's obligations to improve either Area A or Area B are
substantially completed prior to the Area A Commencement Date or the Area B
Commencement Date, as the case may be, and Landlord and Tenant agree, without in
any way being bound to so

                                      10
<PAGE>

agree, Tenant may take possession of such portion the Premises or part thereof
prior to the applicable Commencement Date for the purpose of conducting therein
its normal business operations. In such event, all of the covenants and
conditions of this Lease shall be binding upon the parties hereto with respect
to such whole or part of the Premises as of the date when Tenant took possession
and Tenant shall pay Base Rent at the initial annual rate stated herein, without
abatement, prorated for the period of such occupancy prior to the applicable
Commencement Date. If less than the whole Premises are occupied, Rent shall also
be prorated based on the percentage the occupied portion comprises of the full
Premises.

          C.   Under no circumstances shall the occurrence of any of the events
described in this Section 5 be deemed to accelerate or defer the Termination
Date.

          D.   The Tenant's taking possession of any portion of the Premises
shall be conclusive evidence that such portion of the Premises was in good order
and satisfactory condition when the Tenant took possession, except as to latent
defects (which exception shall be effective for an eighteen (18) month period
following the date the Premises are ready for occupancy, excluding items of
damage caused by Tenant, its agents, contractors and suppliers) and defects
contained on a punch list to be prepared and signed by Landlord and Tenant based
on an inspection made prior to the date on which Tenant takes possession of such
portion of the Premises.  No promise of the Landlord to construct, alter,
remodel or improve the Premises or the Building and no representation by
Landlord or its agents respecting the condition of the Premises or the Building
have been made to Tenant or relied upon by Tenant other than as may be contained
in this Lease.

     E.   Notwithstanding anything in this Paragraph 5 to the contrary, Tenant
shall be permitted access to the Premises prior to each Commencement Date, in
accordance with and subject to, the provisions of Paragraph 5 of the Work Letter
attached hereto as Exhibit C.

     6.   SERVICES.
          --------

          A.   List of Services. Landlord shall provide the following services:
               ----------------

          (i)  Heating and air conditioning when necessary for normal comfort in
     the Premises, from Monday through Friday, during the period from 8 a.m. to
     6 p.m. and on Saturday during the period from 8 a.m. to 1 p.m., excluding
     holidays (as recognized by other similar class office buildings in the
     downtown Chicago area). Tenant will pay for all heating and air
     conditioning requested and furnished prior to or following such hours and
     on Sundays and holidays at rates to be established from time to time by
     Landlord.  (Landlord's current rate therefor being $80.00 per hour, which
     rate is subject to increase from time to time and is limited to increases
     in Landlord's actual costs in providing such additional service).
     Landlord's obligations with respect to heating and air conditioning are
     subject to all governmental rules, regulations and guidelines applicable
     thereto.  As of the date of this Lease, Landlord's heating and cooling
     standards for the Building comply (and during the Term will continue to
     comply) with ASHRAE Standard 62-1989 (and any changes thereto).

                                      11
<PAGE>

          (ii)  City water from the regular Building outlets for drinking,
     lavatory and toilet purposes at all times, twenty-four (24) hours per day,
     seven (7) days per week (so long as it is available to the Building).

          (iii) Janitorial services Monday through Friday in and about the
     Premises, in accordance with the cleaning specifications attached hereto as
     Exhibit D.

          (iv)  Window washing of the inside and outside of those windows in the
     Building's perimeter walls which are situated in the Premises at intervals
     to be determined by Landlord, but not less than three (3) times per annum.

          (v)   Adequate automatic passenger elevator service at all times,
     twenty-four (24) hours per day, seven (7) days per week.

          (vi)  Freight elevator services subject to scheduling by Landlord to
     be made available to Tenant free of charge during Tenant's initial move
     into each floor of the Premises and at Landlord's standard building charge
     thereafter.

          (vii) Operation of the condenser water loop, twenty-four (24) hours
     per day, seven (7) days per week, but in no event shall Landlord be
     required to provide more than thirty (30) tons of capacity for the entirety
     of the Premises, of which fifteen (15) tons shall be allocated to Area A
     and fifteen (15) tons allocated to Area B (provided, however, that if
     Landlord completes installation of a separate cooling tower system for
     tenant use, which will be made available to serve the Premises, in that
     instance Landlord shall have the right to charge Tenant a connection fee in
     order to reimburse Landlord for the actual costs of connecting the Premises
     to such system, plus the Tenant's Proportionate Share of the actual costs
     for the entire cooling tower, pumps and risers amortized over the useful
     life of such equipment).  Landlord shall provide Tenant with seven (7)
     days' advance notice (except in an emergency) of any intended or scheduled
     condenser water system shut-down.

          Landlord also shall provide adequate electrical service to the
electrical closet for standard building lighting fixtures and for Tenant's
incidental uses. Tenant shall bear the cost of replacement of all lamps, tubes,
ballasts and starters for lighting fixtures. With respect to such standard
building lighting fixtures and incidental uses, adequate electrical service will
be furnished in the Premises by Landlord, provided that (a) the connected
electrical load does not exceed an average of six (6) watts per square foot of
the Premises; (b) the electricity so furnished will be at a nominal 120 volts
and no electrical circuit for the supply of such lighting and incidental use
will have a current capacity exceeding 15 amperes; and (c) such electricity will
be used only for standard building lighting fixtures and equipment and
accessories normal to the permitted uses described in Section 4.B hereof. If
Tenant's requirements for electricity are in excess of those set forth in the
preceding sentence, the Landlord reserves the right to require Tenant to install
the conduit, wiring and other equipment necessary to supply electricity for such

                                      12
<PAGE>

excess lighting and incidental use requirements at the Tenant's expense by
arrangement with Commonwealth Edison Company or another approved local utility.

          B.   Billing for Electricity.  The Premises shall be separately
               -----------------------
metered, and Tenant shall pay for the use of all electrical service to the
Premises (other than the electrical service necessary for Landlord to fulfill
its obligation to provide heating and air conditioning as provided in
Subparagraph 6A(i) hereof) without mark-up by the Landlord.  Tenant shall be
billed directly by the utility company supplying electricity to the Premises,
and Tenant agrees to pay each bill promptly in accordance with its terms.

          C.   Interruption of Services. Except for the limited abatement of
               ------------------------
Rent upon a fire or casualty described in Section 11, Tenant agrees that
Landlord shall not be liable in damages, by abatement of Rent or otherwise, for
failure to furnish or delay in furnishing any service, or for any diminution in
the quality or quantity thereof, when such failure or delay or diminution is
occasioned, in whole or in part, by repairs, renewals, or improvements, by any
strike, lockout or other labor trouble, by inability to secure electricity, gas
or other fuel, or water, at the Building commercially after reasonable effort so
to do, by any accident or casualty whatsoever, by act or default of Tenant or
other parties, or by any cause beyond Landlord's reasonable control. Such
failures or delays or diminution shall never be deemed to constitute an eviction
or disturbance of Tenant's use or possession of the Premises or relieve Tenant
from paying Rent or performing any of its obligations under this Lease. Landlord
shall be diligent in its efforts to cure any such interruption of service.
Notwithstanding the foregoing, in the event that any such interruption in the
furnishing of any of the foregoing services in accordance with the standards and
otherwise pursuant to this Section 6.C which was within the reasonable control
of Landlord to prevent continues beyond five (5) consecutive business days and
materially and adversely affects Tenant's ability to conduct its business in the
Premises, or any portion thereof, and on account thereof Tenant ceases doing
business in the Premises, or such portion thereof, Base Rent and Additional Rent
pursuant to Sections 2 and 3 shall equitably abate from and after the date of
such interference for so long as and to the extent Tenant's ability to conduct
its business in the Premises or such portion thereof is so affected.  In the
event that any of the foregoing continues for more than one hundred twenty (120)
days due to causes within the reasonable control of Landlord to prevent, Tenant
may elect to terminate this Lease by giving thirty (30) days' written notice to
Landlord, which notice shall be given within the fifteen (15) day period
following expiration of such one hundred twenty (120) day period, unless within
such thirty (30) days, the services are restored or Tenant begins using the
Premises again for the conduct of business.

          D.   Charges for Services. Charges for any service for which Tenant
               --------------------
is required to pay, from time to time hereunder, including but not limited to
after hours hoisting services or after hours heating or air conditioning shall
be due and payable at the same time as the installment of Rent with which they
are billed, or if billed separately, shall be due and payable within thirty (30)
days after such billing. If Tenant shall fail to make payment for any such
services, Landlord may, with notice to Tenant, discontinue any or all of such
services and such discontinuance shall not be deemed to constitute an eviction
or disturbance of Tenant's use and possession of the Premises or relieve Tenant
from paying Rent or performing any of its other

                                      13
<PAGE>

obligations under this Lease. Tenant shall not be responsible for any charges
for services in connection with the initial improvement of the Premises pursuant
to the Work Letter attached hereto as Exhibit C or in connection with Tenant's
initial move into the Premises.

          E.   Energy Conservation. Notwithstanding anything to the contrary in
               -------------------
this Section 6 or elsewhere in this Lease, Landlord shall have the right to
institute such policies, programs and measures as may be necessary or desirable,
in Landlord's discretion, for the conservation and/or preservation of energy or
energy related services, or as may be required to comply with any applicable
codes, rules and regulations, whether mandatory or voluntary, so long as such
policies and programs do not materially and adversely impact  Tenant's normal
business operations and are enforced in the Building in a non-discriminatory
manner.



     7.   REPAIRS.
          -------

          Subject to the terms of Section 11 hereof, Tenant will, at Tenant's
own expense, keep the Premises in good order, repair and condition at all times
during the Term, and Tenant shall promptly and adequately repair all damage to
the Premises and replace or repair all damaged or broken fixtures and
appurtenances, under the supervision and subject to the approval of the
Landlord, and within any reasonable period of time specified by the Landlord. If
Tenant does not do so, Landlord may, upon prior reasonable notice (except no
notice shall be necessary in an emergency) but need not, make such repairs and
replacements, and Tenant shall pay Landlord the cost thereof, including a
percentage (not to exceed 10%) of the costs thereof sufficient to reimburse
Landlord for all overhead, general conditions, fees and other costs or expenses
arising from Landlord's involvement with such repairs and replacements,
forthwith upon being billed for same. Landlord may, but shall not be required
to, enter the Premises at all reasonable times to make such repairs,
alterations, improvements and additions to the Premises or to the Building or to
any equipment located in the Building as Landlord shall desire or deem necessary
or as Landlord may be required to do by governmental authority or court order or
decree.

     Tenant shall, at its own cost and expense, enter into a regularly scheduled
preventive maintenance/service contract with a maintenance contractor for
servicing Tenant's supplemental HVAC system within the Premises.  The
maintenance contractor and the contract shall be approved by Landlord, which
approval shall not unreasonably be withheld.  The service contract must include
services suggested by the equipment manufacturer within the
operation/maintenance manual and must become effective (and a copy thereof
delivered to Landlord) within thirty (30) days of the Area A Commencement Date.

     Landlord shall, at Landlord's expense (subject to inclusion of such
expenses in Operating Expenses to the extent permitted by Section 3 hereof),
keep in good order, repair and condition consistent with a Class "A" office
building in downtown Chicago and maintain in compliance with all applicable laws
at all times during the Term, all structural elements of the Building, including
floor and ceiling slabs, the exterior walls and windows, the roof, common
Building

                                      14
<PAGE>

mechanical, plumbing, electrical and HVAC systems, the elevators, the washrooms,
the lobby of the Building and all other common areas of the Building to the
extent such systems or common areas service or are of benefit to the Premises.

     8.   ADDITIONS AND ALTERATIONS.
          -------------------------

          A.   Tenant shall not, without the prior written consent of Landlord,
which consent shall not unreasonably be withheld or delayed (so long as the
structural parts of the Building or Building systems are not involved), make any
alterations, improvements or additions to the Premises. Landlord's refusal to
give said consent shall be conclusive. If Landlord consents to said alterations,
improvements or additions, it may impose such conditions with respect thereto as
Landlord deems appropriate, including, without limitation, requiring Tenant to
furnish Landlord with security for the payment of all costs to be incurred in
connection with such work, insurance against liabilities which may arise out of
such work, plans and specifications plus permits necessary for such work and
"as-built" drawings or an accurately marked record set of drawings showing the
actual location of said alterations, improvements and additions. The work
necessary to make any alterations, improvements or additions to the Premises
subsequent to the Commencement Date shall be done at Tenant's expense by
employees of, or contractors hired by, Landlord except to the extent Landlord
gives its prior written consent to Tenant's hiring its own contractors (which
consent shall not be unreasonably withheld, except that Landlord may withhold
consent in cases involving changes to, modifications of or impact upon Building
Systems such as plumbing, HVAC and electrical). Tenant shall promptly pay to
Landlord or the Tenant's contractors, as the case may be, when due, the cost of
all such work and of all decorating required by reason thereof. Tenant shall
also pay to Landlord a percentage (not to exceed 10%) of the cost of such work
(such percentage to be established on a uniform basis for the Building)
sufficient to reimburse Landlord for all overhead, general conditions, fees and
other costs and expenses arising from Landlord's involvement with such work
forthwith upon being billed for the same. Upon completion of such work Tenant
shall deliver to Landlord, if payment is made directly to contractors, evidence
of payment, contractors' affidavits and full and final waivers of all liens for
labor, services or materials all in form satisfactory to Landlord. Tenant shall
defend and hold Landlord and the Land and Building harmless from all costs,
damages, liens and expenses related to such work. All work done by Tenant or its
contractors pursuant to Section 7 or 8 shall be done in a first-class
workmanlike manner using only good grades of materials and shall comply with all
insurance requirements and all applicable laws and ordinances and rules and
regulations of governmental departments or agencies.

     9.   COVENANT AGAINST LIENS.
          ----------------------

          Tenant has no authority or power to cause or permit any lien or
encumbrance of any kind whatsoever, whether created by act of Tenant, operation
of law or otherwise, to attach to or be placed upon Landlord's title or interest
in the Land, Building or Premises, and any and all liens and encumbrances
created by Tenant shall attach to Tenant's interest only. Tenant covenants and
agrees not to suffer or permit any lien of mechanics or materialmen or others to
be placed against the Land, Building or the Premises with respect to work or
services claimed to have been performed for or materials claimed to have been
furnished to Tenant or the Premises,

                                      15
<PAGE>

and, in case of any such lien attaching, or claim thereof being asserted, Tenant
covenants and agrees to cause it to be immediately released and removed of
record. In the event that such lien is not released and removed or bonded over
in a manner satisfactory to Landlord within ten (10) days following notice
thereof from Landlord, Landlord, at its sole option, may take all action
necessary to release and remove such lien (without any duty to investigate the
validity thereof) and Tenant shall promptly upon notice reimburse Landlord for
all sums, costs and expenses (including reasonable attorney's fees) incurred by
Landlord in connection with such lien.

     10.  INSURANCE.
          ---------

          A.   Waiver of Subrogation. Landlord and Tenant each hereby waive any
               ---------------------
and every claim for recovery from the other for any and all loss of or damage to
the Building or Premises or to the contents thereof, which loss or damage is
covered by valid and collectible physical damage insurance policies, or which
would be covered if insurance required hereunder were in effect. Inasmuch as
this mutual waiver will preclude the assignment of any such claim by subrogation
(or otherwise) to an insurance company (or any other person), Landlord and
Tenant each agree to give to each insurance company which has issued, or in the
future may issue, to it policies of physical damage insurance, written notice of
the terms of this mutual waiver, and to have said insurance policies properly
endorsed, if necessary, to prevent the invalidation of said insurance coverage
by reason of said waiver.

          B.   Coverage. Tenant shall purchase and maintain insurance during
               --------
the entire Term for the benefit of Tenant and Landlord (as their interest may
appear) with terms, coverages and in companies satisfactory to Landlord, and
with such increases in limits as Landlord may from time to time request, but
initially Tenant shall maintain the following coverages in the following
amounts:

          (i)  Comprehensive General Liability Insurance naming Tenant,
     Landlord, Landlord's mortgage lender, Landlord's beneficiary and Landlord's
     management agent covering any liability for bodily injury, personal injury
     and property damage arising out of Tenant's operations, assumed liabilities
     or use of the Premises, for limits of liability not less than:

               Bodily Injury Liability       $3,000,000 each occurrence
                                             $3,000,000 annual aggregate

               Personal Injury Liability     $3,000,000 annual aggregate

               Property Damage Liability     $1,000,000 each occurrence
                                             $1,000,000 annual aggregate

          (ii) Physical Damage Insurance covering all office furniture, trade
     fixtures, office equipment, merchandise and all other items of Tenant's
     property on the Premises. Such insurance shall be written on an "all risks"
     of physical loss or damage basis, for the

                                      16
<PAGE>

     full replacement cost value of the covered items and in amounts that meet
     any coinsurance clause of the policies of insurance.

Tenant shall, prior to the commencement of the Term, furnish to Landlord
certificates evidencing such coverage, which certificates shall state that such
insurance coverage may not be changed or canceled without at least ten days
prior written notice to Landlord and Tenant.

          C.   Avoid Action Increasing Rates. Tenant shall comply with all
               -----------------------------
applicable laws and ordinances, all orders and decrees of court and all
requirements of other governmental authorities, and shall not, directly or
indirectly, make any use of the Premises which may thereby be prohibited or be
dangerous to person or property or which may jeopardize any insurance coverage
or may increase the cost of insurance or require additional insurance coverage.
If by reason of the failure of Tenant to comply with the provisions of this
Section 10C, any insurance premium is increased, Tenant shall make immediate
payment of the increased insurance premium upon demand by Landlord or if
insurance coverage is jeopardized, Tenant shall be deemed to be in default under
this Lease.

          D.   Landlord's Insurance. Landlord shall insure the Building on an
               --------------------
"all risks" of physical loss or damage basis, in an amount equivalent to the
full replacement cost of the Building, and shall maintain comprehensive general
liability insurance as is customarily maintained by landlords of first class
office buildings in downtown Chicago, Illinois. These insurance provisions shall
in no way limit or modify Tenant's obligations under the provisions of this
Lease. All insurance premiums on such policies and the deductible portion of any
claims thereunder shall be included in Operating Expenses.

     11.  FIRE OR CASUALTY.
          ----------------

          A.   Section 7 hereof notwithstanding, if the Premises or the Building
(including machinery or equipment used in its operation) shall be damaged by
fire or other casualty and if such damage does not render all or a substantial
portion of the Premises or Building untenantable and if such damage is covered
by Landlord's insurance, then Landlord shall repair and restore the same with
reasonable promptness, subject to reasonable delays for insurance adjustments
and delays caused by matters beyond Landlord's reasonable control, but shall not
be obligated to expend therefor an amount in excess of the proceeds of insurance
recovered with respect thereto. If any such damage is uninsured and not covered
by customary fire and extended coverage insurance, Landlord shall have the right
to terminate this Lease as of the date of such damage (with appropriate
prorations of Rent being made for Tenant's possession subsequent to the date of
such damage of those tenantable portions of the Premises) upon giving written
notice to the Tenant at any time within one hundred twenty (120) days after the
date of such damage. If any such damage renders all or a substantial portion of
the Premises or the Building untenantable, Landlord shall, within forty-five
(45) days after the occurrence of such damage and in good faith, estimate the
length of time that will be required to substantially complete the repair and
restoration of such damage and shall by notice advise Tenant of such estimate.
If it is so estimated that the amount of time required to substantially complete
such repair and restoration will exceed one (1) year from the date such damage
occurred, then either

                                      17
<PAGE>

Landlord or Tenant shall have the right to terminate this Lease as of the date
of such damage upon giving notice to the other at any time within twenty (20)
days after Landlord gives Tenant the notice containing said estimate (it being
understood that Landlord may, if it elects to do so, also give such notice of
termination together with the notice containing said estimate). Landlord shall
have no liability to Tenant, and Tenant shall not be entitled to terminate this
Lease, by virtue of any delays in completion of such repairs and restoration.
Rent, however, shall abate on those portions of the Premises as are, from time
to time, untenantable as a result of such damage. Notwithstanding the foregoing,
if any damage by fire or other casualty occurs within one (1) year of the
Termination Date of this Lease and renders all or more than fifty percent (50%)
of the Premises untenantable, either Landlord or Tenant shall have the right to
terminate this Lease as of the date of such damage upon giving written notice to
the other party at any time within forty-five (45) days after the date of such
damage.

          B.   Landlord shall repair or restore any portion of the alterations,
additions or improvements in the Premises or the decorations thereto to the
extent that such alterations, additions, improvements and decorations were
provided by Landlord at the beginning of the Term or specifically approved of by
Landlord during the Term as provided in Section 8. Landlord shall have no
further obligation pursuant to this Lease to repair or restore any alterations,
additions or improvements in the Premises or the decorations thereto. If Tenant
desires any other or additional repairs or restoration and if Landlord consents
thereto, the same shall be done at Tenant's sole cost and expense subject to all
of the provisions of Sections 7 and 8 hereof. Tenant acknowledges that Landlord
shall be entitled to the full proceeds of any insurance coverage, whether
carried by Landlord or Tenant, for damage to alterations, additions,
improvements or decorations which would become Landlord's property upon the
termination of this Lease.

     12.  WAIVER OF CLAIMS - INDEMNIFICATION.
          ----------------------------------

          To the extent not prohibited by law, Landlord and Landlord's partners,
affiliates, officers, agents, servants and employees shall not be liable for any
damage either to person, property or business or resulting from the loss of use
thereof sustained by Tenant or by other persons due to the Building or any part
thereof or any appurtenances thereof becoming out of repair, or due to the
happening or any accident or event in or about the Building, including the
Premises, or due to any act or neglect of any tenant or occupant of the Building
or of any other person. This provision shall apply particularly, but not
exclusively, to damage caused by gas, electricity, snow, ice, frost, steam,
sewage, sewer gas or odors, fire, water or by the bursting or leaking of pipes,
faucets, sprinklers, plumbing fixtures and windows, and shall apply without
distinction as the person whose act or neglect was responsible for the damage
and whether the damage was due to any of the causes specifically enumerated
above or to some other cause of an entirely different kind. Tenant further
agrees that all personal property upon the Premises, or upon loading docks,
receiving and holding areas, or freight elevators of the Building, shall be at
the risk of Tenant only, and that Landlord shall not be liable for any loss or
damage thereto or theft thereof.  Without limitation of any other provisions
thereof and except to the extent caused by the negligence or willful act of the
Landlord, its officers, agents, servants or employees, Tenant agrees to defend,
protect, indemnify and save harmless Landlord and Landlord's

                                      18
<PAGE>

beneficiary and their respective partners, affiliates, officers, agents,
servants and employees from and against all liability to third parties arising
out of the use of the Premises or acts of Tenant or its servants, agents,
employees, contractors, suppliers, workers or invitee. Except to the extent
caused by the negligence or willful act of Tenant, its officers, agents,
servants and employees, Landlord agrees to defend, protect, indemnify and save
harmless Tenant and its partners, affiliates, officers, agents, servants and
employees from and against all liability to third parties arising out of or in
connection with Landlord's ownership and operation of the Building or Landlord's
activities in the Building or arising from any act of Landlord or its servants,
agents, employees, contractors, suppliers, workers or invitees, but only to the
extent that such liability is not covered by the proceeds of insurance required
to be maintained by Tenant pursuant to Section 10 hereof (whether or not such
insurance is in fact so maintained by Tenant).

     13.  NONWAIVER.
          ---------

          No waiver of any provision of this Lease shall be implied by any
failure of Landlord to enforce any remedy on account of the violation of such
provisions, even if such violation be continued or repeated subsequently, and no
express waiver shall affect any provision other than the one specified in such
waiver and that one only for the time and in the manner specifically stated. No
receipt of monies by Landlord from Tenant after the termination of this Lease
shall in any way alter the length of the Term or of Tenant's right of possession
hereunder or after the giving of any notice shall reinstate, continue or extend
the Term or affect any notice given Tenant prior to the receipt of such monies,
it being agreed that after the service of notice or the commencement of a suit
or after final judgment for possession of the Premises, Landlord may receive and
collect any Rent due, and the payment of said Rent shall not waive or affect
said notice, suit or judgment.

     14.  CONDEMNATION.
          ------------

          A.   In the event all or substantially all of the Building or the
Premises is taken or condemned by eminent domain or by any conveyance in lieu
thereof (such taking, condemnation or conveyance in lieu thereof being
hereinafter referred to as "condemnation"), the Term shall cease and this Lease
shall terminate on the earlier of the date the condemning authority takes
possession or the date title vests in the condemning authority. In the event any
portion of the Building shall be taken by condemnation (whether or not such
taking includes any portion of the Premises), which taking, in Landlord's
judgment, is such that the Building cannot be restored in an economically
feasible manner for use substantially as originally designed, then Landlord
shall have the right, at Landlord's option, to terminate this Lease, effective
as of the date specified by Landlord in a written notice of termination from
Landlord to Tenant. In the event that a portion, but less than substantially
all, of the Premises shall be taken by condemnation, then this Lease shall be
terminated as of the date of such condemnation as to the portion of the Premises
so taken, and, unless Landlord exercises its option to terminate this Lease set
forth in this Section 14, this Lease shall remain in full force and effect as to
the remainder of the Premises. In the event of termination of this Lease
pursuant to the provisions of this Section 14, the Rent shall be apportioned as
of such date of termination; provided, however, that those

                                      19
<PAGE>

provisions of this Lease which are designated to cover matters of termination
and the period thereafter shall survive the termination hereof.

          B.   All compensation awarded or paid upon a condemnation of any
portion of the Building shall belong to and be the property of Landlord without
participation by Tenant. Nothing herein shall be construed, however, to preclude
Tenant from prosecuting any claim directly against the condemning authority for
loss of business, loss of good will, moving expenses, damage to, and cost of
removal of, trade fixtures, furniture and other personal property belonging to
Tenant; provided, however, that Tenant shall make no claim which shall diminish
or adversely affect any award claimed or received by Landlord.

          C.   If any portion of the Land other than the Building is taken by
condemnation or if the temporary use or occupancy of all or any part of the
Premises shall be taken by condemnation during the Term, this Lease shall be and
remain unaffected by such condemnation, and Tenant shall continue to pay in full
the Rent payable hereunder. In the event of any such temporary taking for use or
occupancy of all or any part of the Premises, Tenant shall be entitled to
appear, claim, prove and receive the portion of the award for such taking that
represents compensation for use or occupancy of the Premises during the Term and
Landlord shall be entitled to appear, claim, prove and receive the portion of
the award that represents the cost of restoration of the Premises and the use or
occupancy of the Premises after the end of the Term hereof. In any event of any
such condemnation of any portion of the Land other than the Building, Landlord
shall be entitled to appear, claim, prove and receive all of that award.

     15.  ASSIGNMENT AND SUBLETTING.
          -------------------------

          A.   Subject to any provisions of this Section 15 to the contrary,
Tenant shall not, without the prior written consent of Landlord (which consent
shall not unreasonably be withheld as set forth in Section 15C below) (i)
assign, convey or mortgage this Lease or any interest hereunder; (ii) permit to
occur or permit to exist any assignment of this Lease, or any lien upon Tenant's
interest, voluntarily or by operation of law; (iii) sublet the Premises or any
part thereof; or (iv) permit the use of the Premises by any parties other than
Tenant and its employees. Any such action on the part of Tenant shall be void
and of no effect. There shall be no partial assignment of Tenant's interest in
this Lease. The term "sublease" and all words derived therefrom, as used in this
Section 15, shall include any subsequent sublease or assignment of such sublease
and any other interest arising under such sublease. Landlord's consent to any
assignment, subletting or transfer or Landlord's election to accept any
assignee, subtenant or transferee as the tenant hereunder and to collect rent
from such assignee, subtenant or transferee shall not release Tenant or any
subsequent tenant from any covenant or obligation under this Lease. Landlord's
consent to any assignment, subletting or transfer shall not constitute a waiver
of Landlord's right to withhold its consent to any future assignment,
subletting, or transfer. Landlord may condition its consent upon execution by
the subtenant or assignee of an instrument confirming such restrictions on
further subleasing or assignment and joining in the waivers and indemnities made
by Tenant hereunder.  In any event, Landlord shall respond to Tenant's request
to sublease or assign this Lease within twenty (20) business days of receipt of
Tenant's request.

                                      20
<PAGE>

          B.   If Tenant desires the consent of Landlord to an assignment or
subletting, Tenant shall submit to Landlord at least fifteen (15) business days
prior to the proposed effective date of the assignment or sublease a written
notice which includes:

          1.   all documentation then available related to the proposed sublease
     or assignment (copies of final executed documentation to be supplied on or
     before the effective date); and

          2.   sufficient information to permit Landlord to determine the
     identity and character of the proposed subtenant or assignee and the
     financial condition of the proposed assignee.

          C.   If Landlord does not terminate this Lease, in whole or in part,
pursuant to Section 15D it may, nevertheless, withhold its consent to such
assignment or subletting if:

          1.   in the reasonable judgment of Landlord the subtenant or assignee
     is of a character or engaged in a business or attracts a volume, frequency
     or type of employee or visitor which is not in keeping with the standards
     maintained by Landlord in the Building or that will impose an excessive
     demand on or use of the facilities or services of the Building;

          2.   in the reasonable judgment of Landlord the subtenant or assignee
     does not have the credit comparable to other tenants in the Building;

          3.   in the reasonable judgment of Landlord the purpose for which the
     subtenant or assignee intends to use the subleased space is in violation of
     the terms of this Lease or the lease of any other tenant in the Building
     which prohibits such use;

          4.   the subtenant or assignee is a governmental authority or agency
     or an organization or persons enjoying sovereign or diplomatic immunity; or

          5.   such assignment or subletting would cause a default under another
     lease in the Building or under any ground lease, deed of trust, mortgage,
     restrictive covenant, easement or other encumbrance affecting the Land.

          D.   In addition to withholding its consent, Landlord shall have the
right to terminate this Lease as to that portion of the Premises which Tenant
seeks to assign or sublet, whether by requesting Landlord's consent thereto or
otherwise. Landlord may exercise such right to terminate by giving written
notice to Tenant at any time prior to Landlord's written consent to such
assignment or sublease. In the event Landlord shall exercise its termination
right, Tenant shall have the right to withdraw its notice of intent to assign or
sublease, and thus nullify Landlord's termination exercise, by providing notice
to Landlord within two (2) business days of Landlord's exercise of its
termination right.  In the event that Landlord exercises such right to terminate
(which right is not nullified as set forth in the preceding sentence), Landlord
shall be entitled to recover possession of and Tenant shall surrender such
portion of the Premises on the

                                      21
<PAGE>

proposed date for possession by such assignee or subtenant. Notwithstanding
anything in this Section 15.D to the contrary, Landlord shall have no right to
terminate this Lease as to any area of the Premises which Tenant seeks to
sublease, so long as the aggregate area which Tenant will then have under
sublease to one or more parties shall not exceed one-half (1/2) of the then-
rentable area of the Premises and provided further that all other terms,
covenants and conditions of this Section 15 shall apply to any such sublease.

          E.   In the event that Landlord consents to any assignment or sublease
of any portion of the Premises, as a condition of Landlord's consent, if
Landlord so elects to consent, Tenant shall pay to Landlord any attorneys' fees
and other reasonable costs and expenses incurred by Landlord in connection with
such assignment or sublease plus fifty percent (50%) of all profit (after
deducting therefrom any broker commissions, legal fees, tenant improvement costs
and all other direct and reasonable costs incurred by Tenant in connection with
such assignment or subletting) derived by Tenant from such assignment or
sublease. Tenant shall furnish Landlord with a sworn statement, certified by an
officer of Tenant setting forth in detail the computation of profit (which
computation shall be based upon generally accepted accounting principles), and
Landlord, or its representatives, shall have access to the books, records and
papers of Tenant in relation thereto, and to make copies thereof. Any rent in
excess of that paid by Tenant hereunder for the Premises so assigned or sublet
realized by reason of such assignment or sublease shall be deemed an item of
such profit. If a part of the consideration for such assignment or sublease
shall be payable other than in cash, the payment to Landlord shall be payable in
accordance with the foregoing percentage of the cash and other non-cash
considerations in such form as is satisfactory to Landlord. Such percentage of
Tenant's profits shall be paid to Landlord promptly by Tenant upon Tenant's
receipt from time to time of periodic payments from such assignee or subtenant
or at such other time as Tenant shall realize its profits from such assignment
or sublease. If such sublease or assignment is part of a larger transaction in
which other assets of Tenant are being transferred, the consideration for the
assignment or sublease shall be the fair market value of such assignment or the
fair market rental for such sublease, as reasonably determined by a certified
public accountant agreed upon by Landlord and Tenant.

          F.   Tenant acknowledges that this Lease is a lease of nonresidential
real property and, therefore agrees that Tenant, as the debtor in possession, or
the trustee for Tenant (collectively "the Trustee") in any proceeding under
Title 11 of the United States Bankruptcy Code relating to bankruptcy, as
amended, or under any similar federal or state statute (collectively, the
"Bankruptcy Code"), shall not seek or request any extension of time to assume or
reject this Lease or to perform any obligations of this Lease which arise from
or after the order of relief.

          If the Trustee proposes to assume or to assign this Lease or sublet
the Premises (or any portion thereof) to any person who shall have made a bona
fide offer to accept an assignment of this Lease or a subletting on terms
acceptable to the Trustee, the Trustee shall give Landlord, and lessors and
mortgagees of Landlord of which Tenant has notice, written notice setting forth
the name and address of such person and the terms and conditions of such offer,
no later than twenty (20) days after receipt of such offer, but in any event no
later than ten (10) days prior to

                                      22
<PAGE>

the date on which the Trustee makes application to the bankruptcy court for
authority and approval to enter into such assumption and assignment or
subletting. Landlord shall have the prior right and option, to be exercised by
written notice to the Trustee given at any time prior to the effective date of
such proposed assignment or subletting, to accept an assignment of this Lease or
subletting of the Premises upon the same terms and conditions and for the same
consideration, if any, as the bona fide offer made by such person, less any
brokerage commissions which may be payable out of the consideration to be paid
by such person for the assignment or subletting of this Lease.

          The Trustee shall have the right to assume Tenant's rights and
obligations under this Lease only if the Trustee: (i) promptly cures, or
provides adequate assurance that the Trustee will promptly cure, any default
under this Lease; (ii) compensates, or provides adequate assurance that the
Trustee will promptly compensate, Landlord for any actual pecuniary loss
incurred by Landlord as a result of Tenant's default under this Lease; and (iii)
provides adequate assurance of future performance under this Lease. Adequate
assurance of future performance by the proposed assignee shall include, as a
minimum, that (a) the Trustee or any proposed assignee of this Lease shall
deliver to Landlord a security deposit in an amount equal to at lease three (3)
months' Rent accruing under this Lease and (b) any proposed assignee of this
Lease shall provide to Landlord an audited financial statement, dated no later
than six (6) months prior to the effective date of such proposed assignment or
sublease with no material change therein as to the effective date, which
financial statement shall show the proposed assignee to have a net worth equal
to at least twelve (12) months' Rent accruing under this Lease, or in the
alternative, the proposed assignee shall provide a guarantor of such proposed
assignee's obligations under this Lease, which guarantor shall provide an
audited financial statement meeting the above requirements of this clause (b)
and execute and deliver to Landlord a guaranty agreement in form and substance
acceptable to Landlord. All payments of Rent required of Tenant under this
Lease, whether or not expressly denominated as such in this Lease, shall
constitute rent for the purposes of Title 11 of the Bankruptcy Code.

          The parties agree that for the purposes of the Bankruptcy Code
relating to (i) the obligation of the Trustee to provide adequate assurance that
the Trustee will "promptly" cure defaults and compensate Landlord for actual
pecuniary loss, the word "promptly" shall mean that cure of defaults and
compensation will occur no later than sixty (60) days following the filing of
any motion or application to assume this Lease; and (ii) the obligation of the
Trustee to compensate or to provide adequate assurance that the Trustee will
promptly compensate Landlord for "actual pecuniary loss," the term "actual
pecuniary loss" means, in addition to any other provisions contained herein
relating to Landlord's damages upon default, payments of Rent, including
interest at the interest rate on all unpaid Rent, all attorneys' fees and
related costs of Landlord incurred in connection with any default of Tenant and
in connection with Tenant's bankruptcy proceedings.

          Any person or entity to which this Lease is assigned pursuant to the
provisions of the Bankruptcy Code shall be deemed, without further act or deed,
to have assumed all of the obligations arising under this Lease and each of the
conditions and provisions hereof on and after the date of such assignment. Any
such assignee shall, upon the request of Landlord, forthwith

                                      23
<PAGE>

execute and deliver to Landlord an instrument, in form and substance acceptable
to Landlord, confirming such assumption.

          G.   Tenant shall pay to Landlord all reasonable attorney's fees and
other reasonable costs and expenses incurred by Landlord in reviewing the
documentation and determining whether to consent to any proposed sublease or
assignment (not to exceed, however, $3,000.00), regardless of whether Landlord
consents or does not consent.

          H.   Notwithstanding anything in this Section 15 to the contrary,
Tenant shall have the right, upon ten (10) days' prior written notice to
Landlord, (a) to sublet all or part of the Premises to any related corporation
or other entity which controls Tenant, is controlled by Tenant or is under
common control with Tenant; or (b) to assign this Lease to a successor
corporation or other entity into which or with which Tenant is merged or
consolidated or which acquired substantially all of Tenant's assets and
property; provided that (i) such successor corporation or entity assumes all of
the obligations and liabilities of Tenant and shall have net worth at least
equal to the net worth of Tenant as of the date of this Lease, as determined by
generally accepted accounting principles, and (ii) Tenant provides in its notice
to Landlord the information required in this Section 15. For the purpose hereof
"control" shall mean ownership of not less than 50% of all the voting stock or
legal and equitable interest in such corporation or entity.

     16.  SURRENDER OF POSSESSION.
          -----------------------

          All alterations, improvements and additions to the Premises, whether
temporary or permanent in character, made or paid for by Landlord or Tenant,
shall without compensation to Tenant become Landlord's property at the
termination of this Lease by lapse of time or otherwise and shall, unless
Landlord requests their removal (subject, however, to Landlord's waiver of its
right to require removal as set forth in the next succeeding grammatical
paragraph), be relinquished to Landlord in good condition, ordinary wear and
tear excepted.

          Upon the expiration of the Term or upon the termination of Tenant's
right of possession, whether by lapse of time or at the option of Landlord as
herein provided, Tenant shall forthwith surrender the Premises to Landlord in
good order, repair and condition, ordinary wear and tear excepted, and shall, if
Landlord so requires, remove those alterations, improvements and additions to
the Premises including built-in furniture or shelves and all other attached
items which Landlord shall request Tenant remove and restore the Premises to the
condition existing at the beginning of the Term, ordinary wear and tear
excepted; provided, however, that Tenant shall not be obligated to remove
building standard items or items as to which Landlord has waived in writing, at
the time of approval of their installation pursuant to Section 8 hereof, its
right to require their removal, nor shall Tenant be required to remove any items
of Work installed pursuant to the Work Letter if Landlord has waived in writing
its right to require their removal at the time of Landlord's approval of the
Final Plans therefor.  Prior to the termination of the Term or of Tenant's right
of possession Tenant shall remove its office furniture, trade fixtures, office
equipment and all other items of Tenant's movable property on the Premises.
Tenant shall pay to Landlord upon demand the cost of repairing any damage to the
Premises and to the Building caused by any removal. If Tenant shall fail or
refuse to remove any property which it is required

                                      24
<PAGE>

to remove from the Premises, Tenant shall be conclusively presumed to have
abandoned the same, and title thereto shall thereupon pass to Landlord without
any cost either by set-off, credit, allowance or otherwise, and Landlord may at
its option accept the title to such property or at Tenant's expense may (i)
remove the same or any part in any manner that Landlord shall choose, repairing
any damage to the Premises caused by such removal, and (ii) store, destroy or
otherwise dispose of the same without incurring liability to Tenant or any other
person.

     17.  HOLDING OVER.
          ------------

          Tenant shall pay to Landlord an amount as Rent equal to 200% of one-
twelfth of the Base Rent and 200% of one-twelfth of the Additional Rent payable
by Tenant during the previous Calendar Year herein provided during each month or
portion thereof for which Tenant shall retain possession of the Premises or any
part thereof after the expiration or termination of the Term or of Tenant's
right of possession, whether by lapse of time or otherwise (except that the
first sixty (60) days of any such holding over shall be at 150% of the Base Rent
and 150% of the Additional Rent payable by Tenant during the previous Calendar
Year), and also shall pay all direct damages sustained by Landlord on account
thereof.  It is specifically agreed that Tenant shall have no liability for
consequential damages resulting from a retention of possession beyond the
expiration of the Term; provided, however, that if Landlord shall have given to
Tenant at least sixty (60) days advance notice that Landlord has relet the
Premises, or portions thereof, then if Tenant's holdover continues beyond such
60-day period Landlord's direct damages shall after expiration of such 60-day
period include, without limitation, compensation for the loss of income on
account of such reletting, together with any damages for which Landlord shall be
liable to third parties (including the party releasing the Premises, or portion
thereof), and reasonable legal fees and litigation costs paid by Landlord, as a
result of Tenant's failure to surrender possession of the Premises. The
provisions of this Section 17 shall not be deemed to limit or constitute a
waiver of any other rights or remedies of Landlord provided herein or at law or
in equity.

     18.  ESTOPPEL CERTIFICATE.
          --------------------

          Tenant agrees that, from time to time upon not less than ten business
days' prior request by Landlord, Tenant, or Tenant's duly authorized
representative having knowledge of the following facts, will deliver to Landlord
a statement in writing certifying (i) that this Lease is unmodified and in full
force and effect (or if there have been modifications, a description of such
modifications and that the Lease as modified is in full force and effect); (ii)
the dates to which Rent and other charges have been paid; (iii) that the
Landlord is not in default under any provision of this Lease, or, if in default,
the nature thereof in detail; and (iv) such further matters as are set forth on
the form of estoppel certificate attached hereto as Exhibit F and made a part
hereof, or as may be requested by Landlord, it being intended that any such
statement may be relied upon by any prospective assignee of any tenant of the
Building, any mortgagees or prospective mortgagees thereof, or any prospective
assignee of any mortgagee thereof, or any prospective and/or subsequent
purchaser or transferee of all or a part of Landlord's interest in the Land
and/or Building. Tenant shall execute and deliver whatever instruments may
reasonably be required for such purposes, and in the event Tenant fails so to do
within ten (10) business days after demand in writing, Tenant shall be
considered in default under this Lease.

                                      25
<PAGE>

     19.  OBLIGATIONS TO MORTGAGEES.
          -------------------------

          A.   Subordination.  This Lease is subject and subordinate to all
               -------------
present and future ground or underlying leases of the Land and to the lien of
any mortgages or trust deeds now and hereafter in force against the Land or
Building and to all renewals, extensions, modifications, consolidation and
replacements thereof, and to all advances made or hereafter to be made upon the
security thereof. Tenant shall at Landlord's request execute such further
instruments or assurances as Landlord may deem necessary to evidence, confirm or
effectuate such subordination of this Lease thereto or, if requested, to make
Tenant's interest in this Lease superior thereto. If any mortgage shall be
foreclosed or property encumbered thereby is transferred in lieu of foreclosure,
or if any ground or underlying lease be terminated, (i) the liability of the
mortgagee or trustee hereunder or purchaser at such foreclosure sale or the
liability of a subsequent owner designated as Landlord under this Lease shall
exist only so long as such trustee, mortgagee, purchaser or owner is the owner
of the Land or Building and such liability shall not continue or survive after
further transfer of ownership; and (ii) upon the request of the mortgagee,
trustee or ground lessor, Tenant will attorn, as Tenant under this Lease, to the
purchaser at any foreclosure sale under any mortgage or the ground lessor, by
executing such instruments as may be required by the mortgagee, trustee or
ground lessor.

          B.   Notice to Landlord and Mortgagee.  In the event of any act or
               --------------------------------
omission by Landlord which would give Tenant the right to damages from Landlord
or the right to terminate this Lease, Tenant will not sue for such damages or
exercise any such right to terminate until (i) it shall have given written
notice of the act or omission to Landlord and to the holder(s) of the
indebtedness or other obligations secured by an, mortgage or deed of trust
affecting the Premises or of any ground or underlying lease, if the name and
address of such holder(s) have been furnished to Tenant, and (ii) a reasonable
period of time, in light of the time required to effect a remedy and of the
impact of the act or omission on Tenant's business operations on the Premises,
for remedying the act or omission has elapsed following the giving of the
notice, during which time Landlord and such holder(s), or either of them, their
agents or employees, will be entitled to enter upon the Premises and do therein
whatever may be necessary to remedy the act or omission.

          C.   Non-Disturbance Agreement. Promptly upon execution of this by
               --------------------------
Landlord and Tenant, Landlord shall provide Tenant with a Non-Disturbance
Agreement from Landlord's current mortgage lender in the form attached hereto as
Exhibit G.

     20.  CERTAIN RIGHTS RESERVED BY LANDLORD.
          -----------------------------------

          Landlord shall have the following rights, each of which Landlord may
exercise without notice to Tenant and without liability to Tenant for damage or
injury to property, person or business on account of the exercise thereof, and
the exercise of any such rights shall not be deemed to constitute an eviction or
disturbance of Tenant's use or possession of the Premises and shall not give
rise to any claim for set-off or abatement of rent or any other claim:

                                      26
<PAGE>

          (i)    To change the name or street address of the Building.

          (ii)   To install, affix and maintain any and all signs on the
     exterior or interior of the Building; provided, however, that Landlord
     shall not permit any other tenant of the Building to display its company
     identity or logo at the ground floor lobby of the low-rise elevator bank,
     without granting to Tenant comparable display rights. Tenant shall be
     permitted to display its company identity or logo in the elevator lobbies
     of the fourteenth (14th), fifteenth (15th) and sixteenth (16th) floors of
     the Building, in addition to Building standard signage, at Tenant's sole
     cost and expense and subject to Landlord's prior approval, which approval
     shall not unreasonably be withheld.

          (iii)  To decorate or to make repairs, alterations, additions, or
     improvements, whether structural or otherwise, in and about the Building,
     or any part thereof, and for such purposes to enter upon the Premises, and
     during the continuance of any of said work, to temporarily close doors,
     entryways, public space and corridors in the Building and to interrupt or
     temporarily suspend services or use of facilities, all without affecting
     any of Tenant's obligations hereunder, so long as the Premises are
     reasonably accessible and usable. Except in case of emergency repairs,
     Landlord will give Tenant reasonable advance notice of any contemplated
     stoppage or entry upon the Premises and will use reasonable efforts to
     avoid unnecessary inconvenience to Tenant by reason thereof.

          (iv)   To furnish door keys or magnetic cards for the entry door(s) in
     the Premises at the commencement of the Lease and to retain at all times,
     and to use in appropriate instances, keys to all doors within and into the
     Premises. Tenant's initial supply of magnetic key cards shall be furnished
     by Landlord at no cost to Tenant.  Tenant agrees to purchase only from
     Landlord additional duplicate keys as required, to change no locks, and not
     to affix locks on doors without the prior written consent of the Landlord.
     Notwithstanding the provisions for Landlord's access to the Premises,
     Tenant relieves and releases the Landlord of all responsibility arising out
     of theft, robbery, pilferage and personal assault. Upon the expiration of
     the Term or Tenant's right to possession, Tenant shall return all keys to
     Landlord and shall disclose to Landlord the combination of any safes,
     cabinets or vaults left in the Premises.

          (v)    To designate and approve all window coverings used in the
     Building.

          (vi)   To approve the weight, size and location of safes, vaults,
     vertical files and other heavy equipment and articles in and about the
     Premises and the Building so as not to exceed the legal live load per
     square foot designated by the structural engineers for the Building, and to
     require all such items and furniture and similar items to be moved into or
     out of the Building and Premises only at such times and in such manner as
     Landlord shall direct in writing. Tenant shall not install or operate,
     machinery or any mechanical devices of a nature not directly related to
     Tenant's ordinary use of the Premises without the prior written consent of
     Landlord. Movements of Tenant's property into or out of the Building or
     Premises and within the Building are entirely at the risk and
     responsibility of Tenant

                                      27
<PAGE>

     and Landlord reserves the right to require permits before allowing any
     property to be moved into or out of the Building or Premises.

          (vii)   To establish controls for the purpose of regulating all
     property and packages, both personal and otherwise, to be moved into or out
     of the Building and Premises and all persons using the Building after
     normal office hours.

          (viii)  To regulate delivery and service of supplies and the usage of
     the loading docks, receiving areas and freight elevators.

          (ix)    To show the Premises to prospective tenants at reasonable
     times during the last nine (9) months of the Term and, if vacated or
     abandoned, to show the Premises at any time and to prepare the Premises for
     re-occupancy.

          (x)     Upon prior reasonable notice (which notice may be oral), to
     enter the Premises at any reasonable time to inspect the Premises and, if
     reasonably practicable under the circumstances, accompanied by a
     representative of Tenant.

          (xi)    To close the Building after regular working hours and on
     Saturdays, Sundays and legal holidays subject, however, to Tenant's right
     to admittance to the Premises under such regulations as Landlord may
     prescribe from time to time, which may include, but shall not be limited
     to, a requirement that persons entering or leaving the Building identify
     themselves to a watchman by registration or otherwise and establish their
     right to enter or leave the Building. Such regulations may include, but
     shall not be limited to, the requiring of identification from Tenant's
     employees, agents, clients, customers, invitees, visitors and guests.

     21.  RULES AND REGULATIONS.
          ---------------------

     Tenant agrees to observe the rules and regulations for the Building
attached hereto as Exhibit E and made a part hereof. Landlord shall have the
right from time to time to prescribe additional rules and regulations which, in
its reasonable judgment, may be desirable for the use, entry, operation and
management of the Premises and Building, each of which rules and regulations and
any amendments thereto shall become a part of this Lease. Tenant shall comply
with all such rules and regulations; provided, however, that such rules and
regulations shall not contradict or abrogate any right or privilege herein
expressly granted to Tenant. Landlord agrees not to selectively enforce in a
discriminatory manner against Tenant but not other tenants in the Building any
of the rules and regulations described in this Section 21.

     22.  LANDLORD'S REMEDIES.
          -------------------

          If default shall be made in the payment of the Rent or any installment
thereof or in the payment of any other sum required to be paid by Tenant under
this Lease or under the terms of any other agreement between Landlord and Tenant
and such default shall continue for ten (10) days after written notice to
Tenant, or if default shall be made in the observance or performance

                                      28
<PAGE>

of any of the other covenants or conditions in this Lease which Tenant is
required to observe and perform and such default shall continue for thirty (30)
days after written notice to Tenant, or if a default involves a hazardous
condition and is not cured by Tenant immediately upon written notice to Tenant,
or if the interest of Tenant in this Lease shall be levied on under execution or
other legal process, or if any voluntary petition in bankruptcy or for corporate
reorganization or any similar relief shall be filed by Tenant, or if any
involuntary petition in bankruptcy shall be filed against Tenant under any
federal or state bankruptcy or insolvency act and shall not have been dismissed
within sixty (60) days from the filing thereof, or if a receiver shall be
appointed for Tenant or any of the property of Tenant by any court and such
receiver shall not have been dismissed within sixty (60) days from the date of
its appointment, or if Tenant shall make an assignment for the benefit of
creditors, or if Tenant shall admit in writing Tenant's inability to meet
Tenant's debts as they mature, or if Tenant shall abandon or vacate the Premises
during the Term (accompanied by the failure to pay Rent when due), then Landlord
may treat the occurrence of any one or more of the foregoing events as a breach
of this Lease, and thereupon at its option may, with or without notice or demand
of any kind to Tenant or any other person, have any one or more of the following
described remedies in addition to all other rights and remedies provided at law
or in equity or elsewhere herein:

          (i)  Landlord may terminate this Lease and the Term created hereby, in
     which event Landlord may forthwith repossess the Premises and be entitled
     to recover forthwith, in addition to any other sums or damages, for which
     Tenant may be liable to Landlord, as damages a sum of money equal to the
     excess of the present value of the Rent provided to be paid by Tenant for
     the balance of the Term over the present value of the fair market rent for
     the Premises, after deduction of all anticipated expenses of reletting, for
     said period. For the purpose of determining present value, Landlord and
     Tenant agree that the interest rate shall be the rate applicable to the
     then-current yield on obligations of the U.S. Treasury having a maturity
     date on or about the Termination Date. Should the present value of the fair
     market rent for the Premises, after deduction of all anticipated expenses
     of reletting, for the balance of the Term exceed the present value of the
     Rent provided to be paid by Tenant for the balance of the Term, Landlord
     shall have no obligation to pay to Tenant the excess or any part thereof or
     to credit such excess or any part thereof against any other sums or damages
     for which Tenant may be liable to Landlord.

          (ii) Landlord may terminate Tenant's right of possession and may
     repossess the Premises by forcible entry and detainer suit, by taking
     peaceful possession or otherwise, without terminating this Lease, in which
     event Landlord may, but shall be under no obligation to, relet the same
     (except to the extent required by applicable law) for the account of
     Tenant, for such rent and upon such terms as shall be satisfactory to
     Landlord. For the purpose of such reletting, Landlord is authorized to
     decorate, repair, remodel or alter the Premises. If Landlord shall fail to
     relet the Premises, Tenant shall pay to Landlord as damages a sum equal to
     the amount of the Rent reserved in this Lease for the balance of the Term
     as such Rent shall become due and payable hereunder from time to time
     during the Term. If the Premises are relet and a sufficient sum shall not
     be realized from such reletting after paying all of the costs and expenses
     of all decoration, repairs, remodeling, alterations area additions and the
     expenses of such reletting and of

                                      29
<PAGE>

     the collection of the rent accruing therefrom to satisfy the Rent provided
     for in this Lease, Tenant shall satisfy and pay the same upon demand
     therefor from time to time. Tenant shall not be entitled to any rents
     received by Landlord in excess of the Rent provided for in this Lease.
     Tenant agrees that Landlord may file suit to recover any sums falling due
     under the terms of this Section 22 from time to time and that no suit or
     recovery of any portion due Landlord hereunder shall be any defense to any
     subsequent action brought for any amount not theretofore reduced to
     judgment in favor of Landlord.

          In addition to all other damages, in either case (i) or (ii) above,
Tenant hereby acknowledges that any abatement of Base Rent at the beginning of
the Term, the Allowance (as such term is defined in the Work Letter) and all
commissions paid by Landlord to the brokers named in Section 26 hereof in
connection with this Lease (collectively, "the Incentives"), have been provided
by Landlord upon the express condition that Tenant shall not default in the
payment of Rent during the Term. If Tenant does default in the payment of Rent
hereunder then Landlord shall be entitled to recover as damages, an amount equal
to the unamortized portion of the Incentives. The Incentives will be amortized
evenly over the seven (7) years of the Term, with interest at 12%, as if the sum
of the Incentives were the principal balance of a mortgage loan for such period
at such interest rate being repaid in equal monthly installments of principal
and interest.

     23.  EXPENSES OF ENFORCEMENT.
          -----------------------

          Either party hereto shall pay to the other (the "Prevailing Party"),
upon demand, all costs, charges and expenses, including the fees and out-of-
pocket expenses of counsel, agents and others retained by the Prevailing Party,
incurred in successfully enforcing the other party's obligations hereunder.
Tenant shall pay upon demand all Landlord's costs, charges and expenses,
including the fees and out-of-pocket expenses of counsel, agents and others
retained by Landlord, incurred by Landlord in any litigation, negotiation or
transaction in which Tenant causes Landlord without Landlord's fault to become
involved or concerned.

     24.  COVENANT OF QUIET ENJOYMENT.
          ---------------------------

          Landlord covenants that Tenant, on paying the Rent, charges for
services and other payments herein reserved and on keeping, observing and
performing all the other terms, covenants, conditions, provisions and agreements
herein contained on the part of Tenant to be kept, observed and performed,
shall, during the Term, peaceably and quietly have, hold and enjoy the Premises
subject to the terms, covenants, conditions, provisions and agreements hereof.


     25.  LETTER OF CREDIT.
          ----------------

          A.   As a security for the full and prompt performance by Tenant of
all Tenant's obligations hereunder, Tenant has upon execution of this Lease
provided to Landlord an unconditional irrevocable letter of credit in favor of
Landlord from a bank approved by Landlord, in the form attached hereto as
Exhibit H (the "Original Letter of Credit"), which shall provide for

                                      30
<PAGE>

security in the amount of $547,425.00. Tenant shall, no later than July 1, 2001,
provide to Landlord a second unconditional irrevocable letter of credit in favor
of Landlord from a bank approved by Landlord in the form attached hereto as
Exhibit H (the "Replacement Letter of Credit"), which shall provide for security
in the amount of $1,313,480.00. Upon receipt of the Replacement Letter of
Credit, Landlord shall promptly return to Tenant the Original Letter of Credit.
As used herein, the term "Letter of Credit" shall refer to either the Original
Letter of Credit, or the Replacement Letter of Credit, as the case may be.
Provided Landlord has not theretofore drawn on the Letter of Credit and provided
Tenant is not then in default (beyond any applicable cure period) in the payment
of Rent or other sums due and owing to Landlord under this Lease or in default
under any other material terms, covenant or condition of this Lease, the Letter
of Credit shall be reduced as follows: To the sum of $985,110.00 effective the
first (1st) anniversary of the Area B Commencement Date; to the sum of
$656,740.00 effective the second (2nd) anniversary of the Area B Commencement
Date; to the sum of $328,370.00 effective the third (3rd) anniversary of the
Area B Commencement Date; and to the sum of $66,000.00 effective on the fourth
(4th) anniversary of the Area B Commencement Date. Tenant agrees that, in the
event of any default by Tenant under this Lease (after expiration of all
applicable notice and cure periods), Landlord shall have the right to draw down
on the Letter of Credit in an amount necessary to cure such default ("the Cure
Amount") and Tenant agrees that within ten (10) business days after such initial
draw of the Cure Amount Tenant shall replenish the Cure Amount and shall cause
the Letter of Credit to be amended in a manner that it is restored to the full
amount available thereunder prior to such draw by Landlord. Tenant further
agrees that, in addition to all of the rights and remedies provided to Landlord
pursuant to Section 22 hereof, whether or not this Lease or Tenant's right to
possession hereunder has been terminated, (a) in the event Tenant is in default
under any of the terms, covenants and conditions of this Lease and Tenant has so
failed to replenish the Letter of Credit as aforesaid, or (b) in the event
Tenant has filed (or there has been filed against Tenant) a petition for
bankruptcy protection or other protection from its creditors under any
applicable and available law, then Landlord may at once and without notice to
Tenant to entitled to draw down on the entire amount of the Letter of Credit
then available to Landlord and apply such resulting sums toward (i)
reimbursement to Landlord for all Landlord's then unamortized costs incurred in
leasing to Tenant the Premises demised by this Lease, and (ii) reimbursement to
Landlord for any other damages suffered by Landlord as a result of such default.

          B.   Subject to the terms and conditions set forth above, the
foregoing Letter of Credit shall provide for an original expiration date of at
least twelve (12) months following the date of original issuance thereof, and
shall be automatically extended without amendment (subject to the reductions
described in Paragraph A. above) for an additional one-year period from the
original expiration date or any future expiration date thereof, unless sixty
days prior to any such expiration date the bank sends to Landlord by
certified/registered mail, return receipt requested or overnight courier written
advice that the bank has elected not to consider the Letter of Credit renewed
for any such additional one-year period. In the event such bank so advises
Landlord that such Letter of Credit will not be so renewed, Landlord shall
promptly thereafter notify Tenant thereof in writing, and Tenant shall have the
right to obtain a substitute Letter of Credit from a bank reasonably approved by
Landlord meeting all of the terms and conditions described in Paragraph A.
above, which substitute Letter of Credit ("Substitute Letter of Credit")

                                      31
<PAGE>

shall be reasonably satisfactory to Landlord and delivered to Landlord no later
than thirty (30) days prior to the Expiration Date of such Letter of Credit then
in effect. In the event Tenant fails to deliver such Substitute Letter of Credit
to Landlord at least thirty (30) days prior to the Expiration Date of such
instance have the right without further notice to Tenant to immediately draw
down on the entire amount of the Letter of Credit then available to Landlord; in
such instance Landlord shall retain such resulting sum as a Cash Security
Deposit, and Landlord shall have the right to use such Cash Security Deposit to
the same extent that Landlord would be entitled to draw down on the Letter of
Credit pursuant to the terms of Paragraph A. above. At no time shall Landlord
draw against the Letter of Credit (or Cash Security Deposit, as the case may be)
in an amount greater than the amount provided in Paragraph A. above.

          C.   As between Landlord and Tenant only, all draws under the Letter
of Credit and rights of Landlord to apply the proceeds of any such draw or draft
shall be subject to the provisions of this Lease, including all applicable
notice and cure periods provided Section 22 hereof, if any.

          D.   Tenant acknowledges that Landlord has the right to transfer or
mortgage its interest in the Land and the Building and in this Lease and Tenant
agrees that in the event of any such transfer or mortgage, Landlord shall have
the right to transfer or assign the Letter of Credit (or any resulting Cash
Security Deposit, as the case may be) to the transferee or mortgagee.  Upon such
transfer or assignment, Landlord shall thereby be released by Tenant from all
liability or obligation for the return of such Letter of Credit (or Cash
Security Deposit) and Tenant shall look solely to such transferee or mortgagee
for the return of the Letter of Credit (or Cash Security Deposit).

          E.   Provided Landlord has not theretofore drawn on the Letter of
Credit and provided Tenant is not then in default in the payment of Rent or
other sums due and owing to Landlord under this Lease or in default under any
other material term, covenant or condition of this Lease, Landlord shall return
to Tenant the Letter of Credit within thirty (30) days following the fourth
(4th) anniversary of the Area B Commencement Date.

     26.  REAL ESTATE BROKER.
          ------------------

          Landlord and Tenant each represents that it has dealt with (and only
with) The John Buck Company and Cushman & Wakefield of Illinois, Inc. as brokers
in connection with this Lease, and that insofar as each party knows, no other
broker negotiated this Lease or is entitled to any commission in connection
therewith. Landlord and Tenant each agrees to indemnify, defend and hold the
other, its beneficiaries or its partners, and any of its or their employees,
agents, legal representatives, officers, partners, successors or assigns
harmless from and against any claims made by any broker or finder other than the
brokers named above for a commission or fee in connection with this Lease.

     27.  MISCELLANEOUS.
          -------------

                                      32
<PAGE>

          A.   Rights Cumulative.  All rights and remedies of Landlord under
               -----------------
this Lease shall be cumulative and none shall exclude any other rights and
remedies allowed by law.

          B.   Interest.  All payments becoming due under this Lease and
               --------
remaining unpaid when due shall bear interest until paid at the greater of (i)
twelve percent (12%) per annum or (ii) two percent (2%) per annum above the
prime rate or base rate or other comparable reference rate of interest charged
from time to time by Bank One, N.A. (but in no event at a rate which is more
than the highest rate which is at the time lawful in the State of Illinois).

          C.   Terms.  The necessary grammatical changes required to make the
               -----
provisions hereof apply either to corporations or partnerships or individuals,
men or women, as the case may require, shall in all cases be assumed as though
in each case fully expressed.

          D.   Binding Effect.  Each of the provisions of this Lease shall
               --------------
extend to and shall, as the case may require, bind or inure to the benefit not
only of Landlord and of Tenant, but also of their respective successors or
assigns, provided this clause shall not permit any assignment by Tenant contrary
to the provisions of Section 15 hereof.

          E.   Lease Contains All Terms.  All of the representations and
               ------------------------
obligations of Landlord are contained herein and in the Work Letter and other
Exhibits attached hereto, and no modification, waiver or amendment of this Lease
or of any of its conditions or provisions shall be binding upon the Landlord
unless in writing signed by Landlord or by a duly authorized agent of Landlord
empowered by a written authority signed by Landlord.

          F.   Delivery for Examination.  Submission of the Lease for
               ------------------------
examination shall not bind Landlord in any manner, and no Lease or obligations
of the Landlord shall arise until this instrument is signed by both Landlord and
Tenant and delivery is made to each.

          G.   No Air Rights.  No rights to any view or to light or air over any
               -------------
property, whether belonging to Landlord or any other person, are granted to
Tenant by this Lease.

          H.   Modification of Lease.  If any lender requires, as a condition to
               ---------------------
its lending funds the repayment of which is to be secured by a mortgage or trust
deed on the Land and Building or either, that certain modifications be made to
this Lease, which modifications will not require Tenant to pay any additional
amounts or otherwise change materially the rights or obligations of Tenant
hereunder, Tenant shall, upon Landlord's request, execute appropriate
instruments effecting such modifications.

          I.   [Intentionally Omitted].

          J.   Transfer of Landlord's Interest. Tenant acknowledges that
               -------------------------------
Landlord has the right to transfer its interest in the Land and Building and in
this Lease, and Tenant agrees that in the event of any such transfer Landlord
shall automatically be released from all liability under this Lease arising
after the date of such

                                      33
<PAGE>

transfer and Tenant agrees to look solely to such transferee for the performance
of Landlord's obligations hereunder arising after the date of such transfer.
Tenant further acknowledges that Landlord may assign its interest in this Lease
to a mortgage lender as additional security and agrees that such an assignment
shall not release Landlord from its obligations hereunder and that Tenant shall
continue to look to Landlord for the performance of its obligations hereunder.

          K.   Landlord's Title.  Landlord's title is and always shall be
               ----------------
paramount to the title of Tenant. Nothing herein contained shall empower Tenant
to commit or engage in any act which can, shall or may encumber the title of
Landlord.

          L.   Prohibition Against Recording.  Neither this Lease, nor any
               -----------------------------
memorandum, affidavit or other writing with respect thereto, shall be recorded
by Tenant or by anyone acting through, under or on behalf of Tenant, and the
recording thereof in violation of this provision shall make this Lease null and
void at Landlord's election.

          M.   Captions.  The captions of Paragraphs and subparagraphs are for
               --------
convenience only and shall not be deemed to limit, construe, affect or alter the
meaning of such paragraphs or subparagraphs.

          N.   Covenants and Conditions.  All of the covenants of Tenant
               ------------------------
hereunder shall be deemed and construed to be "conditions," if Landlord so
elects, as well as "covenants" as though the words specifically expressing or
importing covenants and conditions were used in each separate instance.

          O.   Only Landlord/Tenant Relationship.  Nothing contained in this
               ---------------------------------
Lease shall be deemed or construed by the parties hereto or by any third party
to create the relationship of principal and agent partnership, joint venturer or
any association between Landlord and Tenant, it being expressly understood and
agreed that neither the method of computation of Rent nor any act of the parties
hereto shall be deemed to create any relationship between Landlord and Tenant
other than the relationship of landlord and tenant.

          P.   Application of Payments.  Landlord shall have the right to apply
               -----------------------
payments received from Tenant pursuant to this Lease (regardless of Tenant's
designation of such payments) to satisfy any obligations of Tenant hereunder, in
such order and amounts, as Landlord in its sole discretion, may elect.

          Q.   Definition of Landlord.  All indemnities, covenants and
               ----------------------
agreements of Tenant contained herein which inure to the benefit of Landlord
shall be construed to also inure to the benefit of Landlord's beneficiaries and
their partners, agents and employees.

          R.   Time of Essence.  Time is of the essence of this Lease and each
               ---------------
of its provisions.

          S.   Time for Performance.  Whenever under the terms of this Lease the
               --------------------
time for performance falls on a Saturday, Sunday or Legal Holiday as defined in
Ill. Rev. Stat. ch. 17,

                                      34
<PAGE>

para. 2201 (1989), as amended, such time for performance shall be on the next
day that is not a Saturday, Sunday or Legal Holiday.

          T.   Governing Law.  Interpretation of this Lease shall be governed by
               -------------
the laws of the State of Illinois.

          U.   Partial Invalidity.  If any term, provision or condition
               ------------------
contained in this Lease shall, to any extent, be invalid or unenforceable, the
remainder of this Lease (or the application of such term, provision or condition
to persons or circumstances other than those in respect to which it is invalid
or unenforceable) shall not be affected thereby, and each and every other term,
provision and condition of this Lease shall be valid and enforceable to the
fullest extent possible permitted by law.

          V.   Parking.  For so long as Landlord retains the right to license to
               -------
tenants of the Building the right to use parking spaces in the parking garage
located at 250 South Wacker Drive in Chicago, Illinois, Landlord shall make
available to Tenant, for the Term of this Lease plus any renewals, four (4)
reserved spaces in such garage at the standard rates then being charged from
time to time for such spaces.  Tenant shall enter into a parking license
agreement with Landlord or the operator of the garage, as the case may be, for
the use of such spaces.


     28.  NOTICES.
          -------

          All notices to be given under this Lease shall be in writing and (i)
delivered personally (effective the day delivered), (ii) deposited in the United
States mail, certified or registered mail with return receipt requested, postage
prepaid (effective upon the earlier of actual receipt or three (3) business days
after the date upon which such notice is deposited in the United States mail) or
(iii) sent by reputable overnight courier (effective the business day following
delivery to such courier), addressed as follows:

          A.   If to Landlord:

               Office of the Building
               200 South Wacker Drive
               Chicago, Illinois 60606
               Attention: Building Manager

or to such other person or such other address designated by notice sent by
Landlord to Tenant.

          B.   If to Tenant:

               TenFold Corporation
               180 West Election Road
               Suite 100
               Draper, Utah 84020

                                      35
<PAGE>

               Attention:  General Counsel

               with a copy to:

               TenFold Corporation
               100 Foster City Blvd.
               Suite 200
               Foster City, California 94404
               Attention:  Lease Administrator

or if no address is inserted above, addressed to Tenant at Tenant's present
address, and, after occupancy of the Premises by Tenant, to Tenant at 200 South
Wacker Drive, Chicago, Illinois 60606, or to such other address as is designated
by Tenant in a notice to Landlord.

     29.  LIMITATION ON LANDLORD'S LIABILITY.
          ----------------------------------

          It is expressly understood and agreed by Tenant that none of
Landlord's covenants, undertakings or agreements are made or intended as
personal covenants, undertakings or agreements by Landlord, its beneficiaries or
its partners, and any liability for damage or breach or nonperformance by
Landlord shall be collectible only out of Landlord's interest in the Building
and no personal liability is assumed by, nor at any time may be asserted
against, Landlord, its beneficiaries or its partners or any of its or their
officers, agents, employees, legal representatives, successors or assigns, all
such liability, if any, being expressly waived and released by Tenant.

     30.  TENANT ALLOWANCES.
          -----------------

          A.   Landlord agrees to pay to Tenant (or credit against invoices
therefor) an allowance in an amount not to exceed Two Million Four Hundred
Sixty-Two Thousand Seven Hundred Seventy-Five and No/100 Dollars ($2,462,775.00)
(the "Tenant Improvement Allowance") (calculated by multiplying $37.50 by
65,674, being the number of rentable square feet in the Premises) to be applied
toward payment or reimbursement of costs incurred by Tenant in connection with
alterations, additions and improvements made to the Premises pursuant to the
Work Letter attached hereto as Exhibit C, including costs incurred by Tenant in
connection with the preparation of architectural, mechanical, electrical and
plumbing drawings for such work (but excluding furnishings, equipment and
personal property purchased by Tenant), and such other costs incurred by Tenant
in connection with improvements for the Premises for initial occupancy as are
approved by and satisfactory to Landlord (Landlord hereby expressly approving
the application of up to $492,555.00 of the Tenant Improvement Allowance toward
the cost of telephone and computer cabling and consulting costs related
thereto). Landlord and Tenant agree that up to $821,137.50 of the Tenant
Improvement Allowance shall be made available in connection with the improvement
of Area A, and up to $1,641,637.50 shall be made available in connection with
the improvement of Area B.

                                      36
<PAGE>

     B.   The foregoing Tenant Improvement Allowance is for Tenant personally
and may not be applied or used for the benefit of any subtenant approved by
Landlord nor will such allowance inure to the benefit of any permitted assignee
of Tenant. It shall be a condition to the application of any such Tenant
Improvement Allowance that Tenant not be in default under any terms, covenants
and conditions of this Lease at any time such any of allowance is requested. The
Tenant Improvement Allowance is applicable only in connection with the initial
preparation of the Premises for occupancy. In the event that Tenant causes any
work to be performed by any contractor or furnished by a supplier other than
those engaged by Landlord, it shall be a condition of Landlord's obligation to
pay the Tenant Improvement Allowance to Tenant that Tenant shall provide to
Landlord contractor's affidavits and waivers of lien covering all labor and
materials expended and used, and invoices reasonably acceptable to Landlord
establishing the actual cost of and full payment for all items purchased with
such allowance.

     C.   So long as Tenant has expended at least Two Million One Hundred
Thirty-Four Thousand Four Hundred Five and No/100 Dollars ($2,134,405.00) of the
Tenant Improvement Allowance toward the work described in the Work Letter
(exclusive of design, architectural and engineering fees), Landlord agrees, upon
written request of Tenant, and provided Tenant is not in default under any of
the terms, covenants or conditions of this Lease, to credit up to $328,370.00 of
any unused portion of the Tenant Improvement Allowance to the Base Rent payable
hereunder by evenly amortizing such unused portion over the remainder of the
initial Term hereof and reducing the monthly installments of Base Rent set forth
in Exhibit B hereof by such amortized amount.

     D.   In the event the cost of the Work described in the Work Letter exceeds
the Tenant Improvement Allowance, Landlord hereby agrees to advance to Tenant,
at Tenant's request, an additional amount (the "Additional Allowance") not to
exceed Three Hundred Twenty-Eight Thousand Three Hundred Seventy and No/100
Dollars ($328,370.00) on the same terms as the Tenant Improvement Allowance;
provided, however, Tenant shall repay the Additional Allowance (or so much
thereof as has been drawn upon by Tenant) to Landlord, as additional monthly
Base Rent, amortizing with interest at the rate of ten percent (10%) per annum
compounded monthly, from the date or dates of disbursement by Landlord through
the Termination Date of the initial Term. Tenant shall promptly execute and
deliver such amendment to the Lease as Landlord shall prepare to confirm such
repayment in the form of a revision to the Base Rent schedule set forth in
Exhibit B attached hereto. In the event all or any portion of the Additional
Allowance has not been drawn by June 30, 2002, such unused portion shall no
longer be available for use by Tenant nor shall Tenant receive any credit
therefor.

     31.  RIGHT OF FIRST OFFER.
          ---------------------

          In the event any contiguous block of space comprising at least 11,000
rentable square feet on the eighteenth (18th) through twenty-second (22nd)
floors of the Building becomes available for leasing by third parties (but
subject only to the rights of any other parties with respect to such space which
may exist as the date hereof), and provided Landlord has a bona fide prospective
third party tenant (a "BFT") prepared to enter into a lease of said space (as
evidenced by a letter of intent signed by Landlord and said BFT), Tenant shall
have and is hereby

                                      37
<PAGE>

granted the right to add such space to the Premises demised hereunder. Landlord
shall notify Tenant in writing of the availability of such space and the
economic terms upon which Landlord and the BFT have agreed. Tenant shall have
(5) business days from receipt of such notice from Landlord within which to
notify Landlord in writing of Tenant's acceptance of such offer to add space to
the Premises on the terms and conditions set forth in Landlord's notice to
Tenant, except that any space so added to the Premises shall be coterminous with
the Term, with a pro rata adjustment of any concessions contained in such offer.
In the event Tenant does not promptly so notify Landlord of its acceptance of
such offer or thereafter promptly enter into a lease amendment which adds such
space to the Premises, Landlord may thereafter lease such space to the BFT and
Tenant shall have no further right or interest in such space during the term of
such lease with the BFT, as the term thereof may be extended, whether by option
to extend or otherwise.

          It shall be conditions of Tenant's right to exercise an option to add
space under this Section that (i) there remains as of the effective date of such
option at least four (4) years on the Term of this Lease, exclusive of any
renewal options (unless said renewal option or options have theretofore been
exercised) and (ii) Tenant is not in default (beyond any applicable cure period)
under any of the terms, covenants or conditions of this Lease at the time Tenant
notifies Landlord of the exercise of such option to add such space to the
Premises or upon the effective date of such option.

          Notwithstanding anything in Section 15 to the contrary, in the event
Tenant shall sublet any or all of the space added pursuant to this Section 31 or
in the event Tenant shall assign this Lease as to any or all of the space added
pursuant to this Section, Tenant shall pay to Landlord fifty percent (50%) of
any profit derived from such subletting or assignment, as such profit is
calculated in accordance with Section 15.

     32.  OPTION TO EXTEND.
          -----------------

          The Term of this Lease may be extended, at the option of Tenant, for
one (1) period of five (5) years, such period being herein sometimes referred to
as the "Extended Term", as follows:

          A.   Such option to extend shall be exercised by Tenant by giving
written notice to Landlord on or before but not later than the last day of the
sixtieth (60th) full calendar month following the Area B Commencement Date.

          B.   The Extended Term shall be on the same terms, convenants and
conditions of this Lease, excluding the provisions of Sections 30 and 32 hereof,
and except for the payment of rent during the Extended Term. Any termination of
this Lease during the original Term of this Lease or the Extended Term shall
terminate all rights hereunder. The option to extend the Term of this Lease is
personal to TenFold Corporation and may not be exercised by or for the benefit
of any other party, other than an assignee to whom this Lease is assigned
pursuant to Section 15.H(b).

                                      38
<PAGE>

          C.     The Base Rent during the Extended Term shall be the Market
Rental Rate as hereafter defined. For purposes of this Lease, "Market Rental
Rate" shall mean the net rental, as of the date for which such Market Rental
Rate is being calculated, per annum per rentable square foot for comparable
space of comparable size for a similar term for fully credit-worthy tenants by
reference to first-class space primarily in the Building, and secondarily in
other buildings comparable to the Building in age and quality in the downtown
Chicago area, but excluding those leases where the tenant has an equity interest
in the property. Upon written request of Tenant, Landlord shall advise Tenant
one (1) month prior to the date by which Tenant must exercise the option granted
hereby, of the Market Rental Rate at which it is prepared to offer the Premises
to Tenant for the Extended Term. In addition to the Base Rent above provided,
Tenant shall and hereby agrees to continue to pay to Landlord Additional Charges
in accordance with the provisions of Section 3 of this Lease.

          D.     It shall be a condition of Tenant's right to exercise Tenant's
option to extend the Term of this Lease that Tenant is not in default under any
of the terms, covenants or conditions of this Lease at the time that Tenant
notifies Landlord of the exercise of such option to extend the Term of this
Lease or upon the effective date of such option.

          E.     In the event Tenant exercises Tenant's option under this
Section 32, Tenant agrees to execute and deliver to Landlord a Lease amendment
setting forth the terms of such option within thirty (30) days of exercise of
such option by Tenant.

          F.     In the event that Tenant, in good faith, fails to agree to the
Market Rental Rate proposed by Landlord with respect to the Extended Term, such
rate shall be determined as follows:

          (i)    If Landlord and Tenant are unable to reach agreement on the
     Market Rental Rate within fifteen (15) days after Landlord notifies Tenant
     of Landlord's determination of the Market Rental Rate pursuant to Section
     32C hereof, then within five (5) business days, Landlord and Tenant shall
     each simultaneously submit to each other in a sealed envelope its good
     faith estimate of the Market Rental Rate. If the higher of such estimates
     is not more than one hundred five percent (105%) of the lower of such
     estimates, then the Market Rental Rate shall be the average of the two
     estimates.

          (ii)   If Landlord and Tenant are unable to agree upon the Market
     Rental Rate by exchange of estimates, then either may, by written notice to
     the other, request to resolve the dispute by arbitration. Within five (5)
     business days after the receipt of such request, each of the parties shall
     select, to act as an arbitrator, an independent MAI appraiser with
     experience in real estate activities, including at least ten (10) years
     experience in appraising office space in the downtown Chicago area. Within
     five (5) business days after the appointment of the last of the two
     appraisers to be appointed, the two appointed appraisers shall select a
     third appraiser meeting the aforementioned criteria. If one party shall
     fail to make an appointment of an appraiser within five (5) business days
     after receipt of a request to arbitrate as provided in this clause (ii),
     then the appraiser chosen by the other party shall choose the other two
     appraisers.

                                      39
<PAGE>

          (iii)  Once the arbitrators have been selected as provided in clause
     (ii) above, then, as soon thereafter as practicable but in any case within
     thirty (30) days, the arbitrators shall select one of the two estimates of
     Market Rental Rate submitted by Landlord and Tenant, and the estimate so
     selected by a majority of the arbitrators shall be the Market Rental Rate
     for the Extended Term.  The decision of the appraisers of the Market Rental
     Rate shall be submitted in writing to, and be final and binding on,
     Landlord and  Tenant.  The party's whose estimate is not selected by the
     arbitrators shall bear the cost of the foregoing arbitration.



     33.  ROOF RIGHTS.
          ------------

     Tenant shall have limited access to and use of the Building's roof as
Tenant may from time to time request for the erection and maintenance of a
satellite antenna dish (not to exceed two meters in diameter) or alternate
communication and data receiving/sending equipment, for its own use, serving
solely the business conducted by Tenant or any subtenants in the Premises, for
the transmission and receipt of radio, microwave and other communication
signals.  Such portion of the roof, when delivered to Tenant, shall be deemed
leased to Tenant for the Term (as it may be extended) subject to Landlord's
right to relocate.  Tenant shall pay the cost to install, maintain, insure and
remove equipment installed on the roof of the Building by Tenant and shall, at
its sole cost and expense, obtain any zoning or other governmental approvals
necessary for such equipment, and repair any and all damage caused to the
Building or any equipment or property as a result of Tenant's exercise of the
rights granted in this Section 33.  Installation of such equipment shall be
performed in accordance with the provisions of Section 8 of this Lease.
Landlord shall not unreasonably withhold any consent required under Section 8 to
installation of such equipment. Tenant agrees that access to the roof shall be
controlled by Landlord in accordance with Landlord's riser maintenance plan and
reasonable and equitable rooftop rules and regulations adopted for the Building
from time to time, and Tenant shall coordinate any activity on the roof of the
Building with prior written notice to and the involvement of Building


                     [THIS SPACE INTENTIONALLY LEFT BLANK]

                                      40
<PAGE>

personnel.  Tenant shall execute a separate license agreement reasonably
satisfactory to Landlord and Tenant governing use of such antenna.

                              LANDLORD:

                              200 SOUTH WACKER DRIVE, L.L.C.

                              By:   The Equitable Life Assurance Society
                                    of the United States, a New York
                                    corporation, solely on behalf and for the
                                    benefit of its Separate Account 8, known
                                    as the "Prime Property Fund"



                                    By:   /s/ John Schoser
                                       -------------------------------------
                                    Name: John Schoser
                                    Its:  Investment Officer




                              TENANT:

ATTEST:                       TENFOLD CORPORATION,
                              a Delaware corporation

By:  /s/ Jason Chu
   ------------------------
   Its: Systems Manager       By:  /s/ Gina Katigbak
       --------------------      -----------------------------
                                 Its: Facilities Director               .
                                     -------------------------

                                       2
<PAGE>

                                   EXHIBIT A
                                   ---------

                            FLOOR PLAN OF PREMISES
                            ----------------------

                                      A-1
<PAGE>

                                   EXHIBIT B
                                   ---------

                                   BASE RENT
                                   ---------



     Rentable Area                             21,897 square feet
     (Lease Year 1 only)

     Rentable Area
     (Lease Year 2 through balance of Term)    65,674 square feet

     Initial Annual Base Rent
     per square foot                           $18.50

     Annual Increase                           $.50 per rentable square foot
                                               beginning in the 2/nd/ Lease Year


<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------
      Lease Year          Rate Per Square Foot        Annual Rate             Monthly Rate
      ----------          --------------------        -----------             ------------
---------------------------------------------------------------------------------------------
<S>                       <C>                        <C>                      <C>
           1                    $18.50               $  405,094.50             $ 33,757.88
---------------------------------------------------------------------------------------------
           2                    $19.00               $1,247,806.00             $103,983.33
---------------------------------------------------------------------------------------------
           3                    $19.50               $1,280,643.00             $106,720.25
---------------------------------------------------------------------------------------------
           4                    $20.00               $1,313,480.00             $109,456.67
---------------------------------------------------------------------------------------------
           5                    $20.50               $1,346,317.00             $112,193.08
---------------------------------------------------------------------------------------------
           6                    $21.00               $1,379,154.00             $114,929.50
---------------------------------------------------------------------------------------------
           7                    $21.50               $1,411,991.00             $117,665.92
---------------------------------------------------------------------------------------------
</TABLE>

                                      B-1
<PAGE>

                                   EXHIBIT C
                                   ---------

                                  WORK LETTER
                                  -----------

                            200 South Wacker Drive
                               Chicago, Illinois


     This Work Letter is attached to and made part of that certain Lease
(referred to herein for convenience as the "Lease"), dated as of the date hereof
between 200 South Wacker Drive, L.L.C. ("Landlord"), and TenFold Corporation
("Tenant"), wherein the Tenant is leasing certain office space comprised of the
entirety of the fourteenth (14/th/), fifteenth (15/th/) and sixteenth (16/th/)
floors and more particularly described in the Lease (the "Premises") in the
building located at 200 South Wacker Drive, in Chicago, Illinois (the
"Building"), as more particularly described in the Lease. In consideration of
the parties entering into the Lease and of the mutual promises and covenants
hereinafter contained, Landlord and Tenant hereby agree as follows:

     1.    Proposed and Final Plans.
           ------------------------

     (a)   Tenant shall cause to be prepared and delivered to Landlord, for
Landlord's approval, the following proposed drawings ("Proposed Plans") for all
improvements Tenant desires to have completed in the Premises (the "Work"):

     (i)   Architectural drawings (consisting of floor construction plan,
           ceiling lighting and layout, power, and telephone plan and, if
           desired by Tenant, any plans for ambient lighting within the occupied
           portions of the Premises).

     (ii)  Mechanical drawings (consisting of HVAC, electrical, telephone, and
           plumbing).

     (iii) Finish schedule (consisting of wall finishes and floor finishes
           and miscellaneous details).

     (iv)  Tenant's HVAC specifications to enable Landlord to install, as part
           of the Work, a connection to the cooling tower for the Building and a
           condenser water loop.

     (b)   All architectural drawings shall be prepared at Tenant's sole cost
and expense (but subject to application of the Tenant Improvement Allowance
provided in Section 30 of the Lease) by a licensed architect designated by
Tenant and approved by Landlord, whom Tenant shall employ. Tenant shall deliver
one set of reproducible architectural drawings to Landlord's engineer at the
same time one set is delivered to Landlord. All mechanical drawings shall be
prepared at Tenant's sole cost and expense (but subject to application of the
Tenant Improvement Allowance provided in Section 30 of the Lease) by a licensed
engineer designated by Landlord, whom Tenant shall employ. Tenant shall
reimburse Landlord for all reasonable out-of-pocket costs incurred by Landlord
in reviewing the Proposed Plans.

                                      C-1
<PAGE>

     (c)  Within five (5) business days after Landlord's receipt of the
architectural drawings, Landlord shall advise Tenant of any changes required to
obtain Landlord's approval, which approval shall not be unreasonably withheld or
conditioned.

     (d)  Within ten (10) business days after receipt of mechanical drawings,
Landlord shall advise Tenant of any changes required to obtain Landlord's
approval, which approval shall not be unreasonably withheld or conditioned.

     (e)  Any changes which Landlord shall require to the architectural drawings
or mechanical drawings shall be limited to matters which have a material or
adverse impact on the structure or systems of the Building or which are visible
from the exterior or common areas of the Building. If Landlord disapproves of
the Proposed Plans, Tenant shall revise the Proposed Plans disapproved by
Landlord and resubmit such plans to Landlord. Landlord shall, within ten (10)
days after receipt of Tenant's revised plans, advise Tenant of any additional
changes which may be required to obtain Landlord's approval. If Landlord
disapproves the revised plans, Tenant shall revise such plans and resubmit them
to Landlord. Landlord shall, again within five (5) business days after receipt
of the revised plans, advise Tenant of further changes, if any, required for
Landlord's approval. This process shall continue until Landlord has approved
Tenant's revised Proposed Plans; Tenant shall at all times use all diligence
that may be required so that Landlord has in all events approved Tenant's
Proposed Plans or revised Proposed Plans (as the case may be) on or before, and
no later than, July 15, 2000. "Final Plans" shall mean the Proposed Plans, as
revised, which have been approved by Landlord and Tenant in writing.

     (f)  All Proposed Plans and Final Plans shall comply with all applicable
statutes, ordinances, regulations, laws, and codes and with the requirements of
Landlord's fire insurance underwriters. Neither review nor approval by Landlord
of the Proposed Plans and resulting Final Plans shall constitute a
representation or warranty by Landlord that such plans either (i) are complete
or suitable for their intended purpose, or (ii) comply with applicable laws,
ordinances, codes and regulations, it being expressly agreed by Tenant that
Landlord assumes no responsibility or liability whatsoever to Tenant or to any
other person or entity for such completeness, suitability or compliance. Tenant
shall not make any changes in the Final Plans without Landlord's prior written
approval.

     2.   Performance of the Work by Landlord.
          -----------------------------------

     Upon approval of the Final Plans by Landlord and filing thereof with the
appropriate governmental agencies, Landlord shall cause the Work to be bid to
Clune Construction.  Landlord and Tenant shall mutually negotiate the contract
for the general contractor to perform the Work, and Landlord shall thereupon
execute the contract with the general contractor.  Upon execution of the general
contractor contract, Landlord, at Tenant's sole cost and expense (but subject to
application of the Tenant Improvement Allowance provided in Section 30 of the
Lease) shall cause such contractor to promptly commence to construct and install
and pursue to completion in the Premises the Work. To the extent the costs of
the Work exceed the Tenant

                                      C-2
<PAGE>

Improvement Allowance, Tenant shall pay to Landlord the costs of the Work
pursuant to the provisions of Paragraph 3 hereof.

     3.   Payment of Costs of the Work.
          ----------------------------

     Subject to the application of the Tenant Improvement Allowance described in
Section 30 of the Lease, the Work shall be installed at Tenant's sole cost and
expense. The cost of the Work shall include, and Tenant agrees to pay Landlord
for, the following costs ("Landlord's Costs"): (i) the cost of all work
performed by Landlord on behalf of Tenant and for all materials and labor
furnished on Tenant's behalf, (ii) the cost of any services provided to Tenant
or its contractors including but not limited to the cost for rubbish removal
(except that there shall be no charge during the construction period for
utilities or freight elevator usage), and (iii) a supervision fee equal to $0.50
per rentable square foot of the Premises. Tenant shall pay to Landlord all of
Landlord's Costs in excess of the Tenant Improvement Allowance. Within ten (10)
business days following selection of the general contractor, Landlord shall
prepare an estimate of Landlord's Costs. To the extent such estimate of
Landlord's Costs exceeds the Tenant Improvement Allowance, Landlord shall
invoice Tenant for such excess upon commencement of the Work, and Tenant shall
pay the same to Landlord within thirty (30) days of Landlord's invoice (and
Landlord shall have no obligation to proceed with the Work until Tenant has paid
such excess to Landlord). Any balance of the excess of the actual amount of
Landlord's Costs over the estimate previously paid and after application of the
Tenant Improvement Allowance, shall be paid by Tenant to Landlord upon
Substantial Completion of the Work. Notwithstanding the foregoing or anything
herein or in the Lease to the contrary, Landlord shall be responsible for
demolition of the kitchen area and the ceramic tile located on the sixteenth
floor of the Building, and Tenant shall have no liability in connection
therewith.

     4.   Commencement of Rent.  Notwithstanding the date provided in the Lease
          --------------------
for the commencement of the Term thereof, the Area A Commencement Date or the
Area B Commencement Date shall be deferred and Tenant's obligation to pay rent
under the Lease with respect to either Area A or Area B, as the case may be,
shall not commence until Landlord shall have substantially completed the Work
therein; provided however, that if Landlord shall be delayed in substantially
completing the Work as a result of any of the following (hereinafter "Tenant
Delays"):

     (a)  Tenant's failure to obtain Landlord's approval of the Final Plans in
accordance with and on or before the deadlines set forth in Paragraph 1 hereof;
or

     (b)  Tenant's changes in the Work (notwithstanding Landlord's approval of
          such changes); or

     (c)  Tenant's failure to negotiate in good faith the contract with Clune
          Construction; or

                                      C-3
<PAGE>

     (d)  The performance or failure thereof by Tenant or any person, firm or
entity employed by Tenant, or the completion or failure to complete any work of
Tenant by said person, firm or entity; or

     (e)  The failure of Tenant to pay the estimate of Landlord's Costs as
provided in Paragraph 3 hereof; or

     (f)  Any fault of Tenant or its agents or representative;

the applicable Commencement Date and the payment of rent under the Lease shall
not be affected or deferred on account of any such Tenant Delays.

     Substantial Completion of the Work in the Premises shall mean completion of
the Work with the exception of minor or insubstantial details of construction,
mechanical adjustment or decoration, the incompletion of which will not
unreasonably interfere with use and occupancy of the Premises by Tenant for
normal business purposes. Such minor or insubstantial details are hereinafter
referred to as the "Punch List Items"; Landlord and Tenant will within two (2)
business days prior to Tenant's delivery and installation of its furniture
systems as set forth in Paragraph 5 below, complete a written punchlist
identifying such items, and within five (5) days after Substantial Completion of
the Work confirm such date in writing and complete preparation of a second
written punchlist. Landlord shall thereafter cause the Punch List Items to be
completed as promptly as reasonably possible. Landlord shall give Tenant fifteen
(15) days prior written notice of the anticipated date of Substantial
Completion. Upon Substantial Completion of the Work, Tenant shall accept the
Premises (subject to the Punch List Items and latent defects as set forth in
Section 5.D of the Lease), provided, however, that such acceptance shall not
relieve Landlord of its obligation to promptly complete all Punch List Items.
The punchlist will be attached to the Term Commencement Memorandum described in
Section 1 of the Lease.

     In addition to Substantial Completion of the Work, the Area A Commencement
Date or the Area B Commencement Date, as the case may be, and Tenant's
obligation to pay rent under the Lease with respect to Area A or Area B, shall
be deferred until: (i) the Building's utility and life safety systems are fully
operable; (ii) the HVAC system serving the Premises (other than any supplemental
system installed by Tenant) are fully operational, tested and balanced; (iii)
Tenant shall have access to all of the parking spaces described in Section 27.V
of the Lease; and (iv) Landlord shall have tendered possession of the Premises
to Tenant.

     5.   Access by Tenant. Landlord, at Landlord's sole discretion, may permit
          ----------------
Tenant and Tenant's agents to enter the Premises as licensees prior to the date
specified as the commencement of the Term of said Lease in order that Tenant may
do such other work as may be required by Tenant to make the Premises ready for
Tenant's use and occupancy thereof including, but not limited to, data cabling,
installation of telephone switch and data equipment, installation of security
system and installation of furniture systems.  Subject to the provisions of
Paragraph 4 above and this Paragraph 5, Landlord shall provide Tenant with
access to the Premises at least fifteen (15) days prior to the date of
Substantial Completion to permit delivery and installation of furniture

                                      C-4
<PAGE>

systems. If Landlord permits such entry prior to the commencement of the Term,
such license is conditioned upon Tenant and Tenant's agents, contractors,
workmen, mechanics, suppliers and invitees working in harmony and not
interfering with Landlord or Landlord's agents in constructing and installing
the Work or doing any other work in or about the Premises or Building, or with
other tenants, invitees and occupants of the Building. If at any time such entry
shall cause or threaten to cause such disharmony or interference therewith,
Landlord shall have the right to withdraw such license upon twenty-four (24)
hours' written notice to Tenant. Tenant agrees that any such entry into and
occupation of the Premises shall be deemed to be under all of the terms,
covenants, conditions and provisions of the Lease except as to the covenant to
pay rent, and further agrees that Landlord shall not be liable in any way for
any injury, loss or damage which may occur to any of Tenant's work or
installations made in the Premises or to property placed therein, and Tenant
agrees to protect, defend, indemnify and save harmless Landlord and Landlord's
principals, agents, beneficiaries and employees from all liabilities, costs,
damages, fees and expenses arising out of or in any way connected with the
activities of Tenant or its agents, contractors, suppliers or workmen in or
about the Premises or Building.

     In the event Tenant employs contractors to do work in the Premises, Tenant
shall secure and pay for Worker's Compensation, Employers Liability Insurance,
and Comprehensive General Liability Insurance in forms and amounts acceptable to
Landlord. All policies shall be endorsed to include Landlord and its employees
and agents as additional insured parties. Certified copies of such policies or,
at Landlord's election, certificates of such insurance shall be delivered to
Landlord prior to Tenant commencing any work in the Premises.

     6.   Miscellaneous.
          -------------

     (a)  Except as expressly set forth herein, Landlord has no other agreement
with Tenant and Landlord has no other obligation to do any other work or pay any
amounts with respect to the Premises. Any other work in the Premises which may
be permitted by Landlord pursuant to the terms and conditions of the Lease shall
be done at Tenant's sole cost and expense and in accordance with the terms and
conditions of the Lease.

     (b)  This Work Letter shall not be deemed applicable to any additional
space added to the original Premises at any time or from time to time, whether
by any options under the Lease or otherwise, or to any portion of the original
Premises or any additions thereto in the event of a renewal or extension of the
initial term of the Lease, whether by any options under the Lease or otherwise,
unless expressly so provided in the Lease or any amendment or supplement
thereto.

     (c)  The failure by Tenant to pay any monies due Landlord pursuant to this
Work Letter within the time period herein stated shall be deemed a default under
the terms of the Lease for which Landlord shall be entitled to exercise all
remedies available to Landlord for nonpayment of Rent. All late payments shall
bear interest pursuant to Section 27.B of the Lease.

     (d)  Tenant shall be solely responsible to determine at the site all
dimensions of the Premises and the Building which affect any work to be
performed by Tenant hereunder.

                                      C-5
<PAGE>

     (e)  Landlord shall not require the general contractor to provide a payment
or performance bond in connection with the Work.

     (f)  Landlord shall provide to Tenant any warranties made available to
Landlord by any subcontractors in connection with the Work.

                                      C-6
<PAGE>

                                   EXHIBIT D
                                   ---------

                            CLEANING SPECIFICATIONS
                            -----------------------

A.   OFFICE AREAS
     ------------

     Daily: Monday through Friday inclusive; holidays excepted.

     1.   Empty all waste receptacles and ash trays; remove waste materials from
          the premises.

     2.   Dry-mop all uncarpeted areas.

     3.   Vacuum all rugs and carpeted areas in offices, lobbies and corridors.

     4.   Hand-dust all office furniture, fixtures and all other horizontal
          surfaces.

     5.   Damp-wipe all glass furniture tops.

     6.   Remove all fingers marks and smudges from doors, door frames, around
          light switches, private entrance glass partitions.

     7.   Wash and clean all water coolers and fountains.

     8.   Spot-clean spill marks on resilient floor tile.

     B.   LAVATORIES (WITHIN THE PREMISES)
          ----------

     Nightly:
     -------

     1.   Clean and damp-mop floors.

     2.   Wash and polish all mirrors, bright work and enameled surfaces.

     3.   Wash and sanitize all basins, bowls and urinal.

     4.   Wash and sanitize toilet seats.

     5.   Dust and clean, wash where necessary, all partitions, tile walls and
          all dispensers and receptacles.

     6.   Empty all receptacles and sanitary disposals.

                                      D-1
<PAGE>

     7.   Fill toilet tissue holders (tissue to be furnished by Landlord). If
          directed by Tenant, fills soap dispensers an paper towel dispenser
          (soap and paper towels to be furnished by Tenant at Tenant's expense).

                                      D-2
<PAGE>

                                   EXHIBIT E
                                   ---------

                             RULES AND REGULATIONS
                             ---------------------


     RULES AND REGULATIONS.  Tenant agrees to observe the rights reserved to
Landlord in the Lease and agrees, for itself, its employees, agents, clients,
customers, invitees and guests, to comply with the following rules and
regulations with such reasonable modifications thereof and additions thereto as
Landlord may make, from time to time, for the Building.

          (a)  Any sign, lettering, picture, notice or advertisement installed
within Tenant's Premises which is visible to the public from within the Building
shall be installed at Tenant's cost and in such manner, character and style as
Landlord may approve in writing such approval not to be unreasonably withheld.
No sign, lettering, picture, notice or advertisement shall be placed on any
outside window or in any position so as to be visible from outside the Building
or from any atrium or lobbies of the Building.

          (b)  Tenant may use the name of the Building or use pictures or
illustrations of the Building in advertising or other publicity, but only with
prior written consent of Landlord. Landlord's consent may be arbitrarily
withheld. Tenant may use the address of the Building as its business address for
any reasonable business purpose.

          (c)  Tenant, its customers, invitees, licensees, and guests shall not
obstruct sidewalks, entrances, passages, courts, corridors, vestibules, halls,
elevators and stairways in and about the Building. Tenant shall not place
objects against glass partitions or doors or windows or adjacent to any open
common space which would be unsightly from the Building corridors or from the
exterior of the Building, and will promptly remove the same upon notice from
Landlord.

          (d)  Tenant shall not make, or cause to be made, any noises,
disturbances, vibrations, odors or noxious fumes which interfere with the use or
enjoyment of the Building or any space located therein by any other tenant or
occupant of the Building. Tenant shall not use or operate any electrical or
electronic devices or other devices that emit excessive sound waves or are
dangerous to other tenants and occupants of the Building or that would interfere
with the operation of any device or equipment or radio or television
broadcasting or reception from or within the Building or elsewhere, and shall
not, except as otherwise expressly provided in Section 33 of the Lease, place or
install any projections, antennae, aerials or similar devices outside of the
Premises.

          (e)  Tenant shall not make any room-to-room canvas to solicit business
from other tenants in the Building, and shall not exhibit, sell or offer to
sell, use, rent or exchange any

                                      E-1
<PAGE>

item or services in or from the Premises unless ordinarily embraced within the
Tenant's use of the Premises as specified in its lease.

          (f)  Tenant shall not waste electricity or water and agrees to
cooperate fully with Landlord to assure the most effective operation of the
Building's heating and air conditioning and shall refrain from attempting to
adjust any controls except for the thermostats within the Premises. Tenant shall
keep public corridor doors closed.

          (g)  Door keys for doors in the Premises will be furnished at the
commencement of the Lease by Landlord. Tenant shall not affix additional locks
on doors and shall purchase duplicate keys only from Landlord. When the Lease is
terminated, Tenant shall return all keys to Landlord and will provide to
Landlord the means of opening any safes, cabinets or vaults left in the
Premises.

          (h)  Tenant assumes full responsibility for protecting its space from
theft, robbery and pilferage. Tenant's responsibility includes keeping doors
locked and other means of entry to the Premises closed and secured.

          (i)  Peddlers, solicitors and beggars shall be reported to the office
of the Building or as Landlord otherwise requests.

          (j)  Tenant shall neither install nor operate machinery or any
mechanical devices of a nature not directly related to Tenant's ordinary use of
the Premises without the written permission of the Landlord.

          (k)  Tenant shall not, and Tenant shall not permit or suffer anyone
to:

               (1)  Use the Premises for lodging or for any immoral or illegal
                    purposes;

               (2)  Use the Premises to engage in the manufacture, sale or use
                    of any spirituous, fermented, intoxicating or alcoholic
                    beverages;

               (3)  Use the Premises to engage in the manufacture or sale of, or
                    permit the use of, any illegal drugs on the Premises.

          (l)  In no event shall any person bring into the Building inflammables
such as gasoline, kerosene, naphtha and benzene, or explosives or firearms or
any other articles of intrinsically dangerous nature. If by reason of the
failure of Tenant to comply with the provisions of this paragraph, any insurance
premium payable by Landlord for all or any part of the Building shall at any
time be increased above normal insurance premiums for insurance not covering the
items aforesaid, Landlord shall have the option to require Tenant to make
immediate payment for the whole of the increased insurance premium.

                                      E-2
<PAGE>

          (m)  Tenant shall comply with all applicable federal, state and
municipal laws, ordinances and regulations and building rules, and shall not
directly or indirectly make any use of the Premises which may be prohibited
thereby or which shall be dangerous to person or property or shall increase the
cost of insurance or require additional insurance coverage.

          (n)  If Tenant desires signal, communication, alarm or other utility
or service connection installed or changed, the same shall be made at the
expense of Tenant, with approval and under direction of Landlord.

          (o)  Bicycles shall not be permitted in the Building in other than
Landlord designated locations.

          (p)  Tenant shall cooperate and participate in all reasonable security
programs affecting the Building.

          (q)  Tenant, its customers, invitees, licensees, and guests shall not
loiter, eat, drink, sit or lie in the lobby, plaza or other spaces in the
Building or the adjacent property owned by the Landlord which are open to the
public.

          (r)  Tenant shall not, and Tenant shall not permit or suffer anyone
to, allow any pets in the Premises.

          (s)  Tenants shall not use any draperies or other window coverings
instead of or in addition to the building standard window coverings designated
and approved by Landlord for exclusive use throughout the Building.

          (t)  Tenant, its customers, invitees, licensees, and guests shall not
use the freight or passenger elevators of the Building except in accord with the
reasonable regulations for their use established by Landlord.

          (u)  In the event Landlord allows one or more tenants in the Building
to do any act prohibited herein, Landlord shall not be precluded from denying
any other tenant the right to do any such act.

          (v)  In the event of a conflict between the terms of these rules and
regulations and the terms of the Lease, the terms of the Lease shall control.

          (w)  No person or contractor not employed by Landlord shall be used to
perform window washing, cleaning, decorating, repair or other work in the
Premises.

          (x)  Tenant shall not, and Tenant shall not permit or suffer anyone
to:

               (1)  Cook in the Premises;

                                      E-3
<PAGE>

               (2)  Place vending or dispensing machines of any kind in or about
                    the premises;

               (3)  At any time sell, purchase or give away, or permit the sale,
                    purchase or gift of, food in any form.

However, with prior written consent of Landlord, such activities may be
permitted in lounges or other facilities designated for this purpose.

                                      E-4
<PAGE>

                                   EXHIBIT F
                                   ---------

                      FORM OF TENANT ESTOPPEL CERTIFICATE
                      -----------------------------------



                         DATED:______________________


Re: Lease Dated:

     Landlord:   200 South Wacker Drive, L.L.C.

     Tenant:

          Premises:   ________________________________________________
                      at 200 Wacker Drive, Chicago, Illinois

     The undersigned as Tenant under the Lease aforesaid, hereby acknowledges
for the benefit of _______________, which has or is about to make a loan to the
Landlord aforesaid, part of the security for which will be a mortgage covering
the Premises aforesaid and an assignment of Landlord's interest in said Lease,
the truth and accuracy of the following statements pertaining to said Lease.

     1.   Tenant has accepted and is in full possession of the Premises.

     2.   The term of the Lease commenced on ___________________ and the Lease
is in full force and effect.

     3.   Landlord has satisfactorily complied with all of the requirements and
conditions precedent to the commencement of the term of the Lease as specified
in the Lease.

     4.   All improvements, additions and alterations required to be made by
Landlord with respect to the Premises have been fully completed by Landlord and
are acceptable to Tenant except for ___________________________________________.

     5.   Tenant is paying the full rent stipulated in the Lease and there are
no offsets, defenses or claims on the part of Tenant with respect thereto.

     6.   The fixed annual rent under the Lease is $_________________ and no
moneys have been paid to Landlord in advance of the due date set forth in the
Lease, except __________ __________________________________.

                                      F-1
<PAGE>

     7.   Landlord has not been and is not presently in default under any of the
terms, covenants or provisions of the Lease.

     8.   There have been no modifications or amendments to the Lease except as
follows: ______________________________________________________________________.

A true and complete copy of the Lease (together with all amendments if any
aforementioned) is attached hereto and hereby made a part hereof.

     9.   Tenant acknowledges that __________ assumes no liability for its
security deposits, if any, or for sums escrowed with the Landlord for taxes in
the event that __________ acquires the building in which the Premises are
located by foreclosure or by transfer of title in lieu of foreclosure.

     10.  Tenant has no notice of any prior assignment, hypothecation or pledge
of the Lease or of the rents payable by Tenant thereunder.

Dated:                                  TENANT:_________________________________

                                        By:_____________________________________

                                      F-2
<PAGE>

Address to which notices are to be
sent if other than the Premises:

                                      F-3
<PAGE>

                                   EXHIBIT G
                                   ---------

                       FORM OF NON-DISTURBANCE AGREEMENT
                       ---------------------------------

                        LEASE SUBORDINATION, ATTORNMENT
                                      AND
                           NON-DISTURBANCE AGREEMENT

     THIS AGREEMENT, made this day of  , 2000, by and between
__________________, a ________________ (herein "Lessee"), and MASSACHUSETTS
MUTUAL LIFE INSURANCE COMPANY, a Massachusetts corporation (herein "Lender").

                                   RECITALS

     A.   Lender is the holder of a certain promissory note (herein the "Note")
issued by 200 South Wacker Drive, L.L.C. ("Lessor"), dated October 23, 1998 in
the principal sum of Sixty-Six Million and No/100 DOLLARS ($66,000,000.00) and
of the Mortgage and Security Agreement of even date therewith (herein the
"Mortgage") securing the Note, recorded on October 26, 1998 as Document Number
98958719 with the Cook County Recorder, which Mortgage encumbers the real
property (herein called the "Subject Property") described on Exhibit A, attached
hereto and made a part hereof.

     B.   Lessee and 200 South Wacker Drive, L.L.C., as Lessor, entered into a
lease agreement (herein the "Lease") dated _________________________, 2000 by
which Lessee leased from Lessor certain premises commonly known as
_____________________ and comprising approximately _______ Square Feet (herein
the "Leased Premises"), and constituting a portion of the Subject Property.

     C.   Lessee desires to be able to obtain the advantages of the Lease and
occupancy thereunder in the event of foreclosure of the Mortgage and Lender
wishes to have Lessee confirm the priority of the Mortgage over the Lease.

     NOW, THEREFORE, in consideration of the mutual covenants and conditions set
forth hereinbelow, the parties hereto agree as follows:

     1.   Lessee hereby covenants and agrees that all its rights and interests
whatsoever under the Lease in the Leased Premises and the Subject Property are
and shall remain subject and subordinate to the lien of the Mortgage and to all
the terms, conditions and provisions thereof, to all advances made or to be made
thereunder or under the Note, and to any increases, renewals, extensions,
modifications, substitutions, consolidations or replacements thereof or of the
Note.

     2.   So long as Lessee is not in default (beyond any period given Lessee in
the Lease to cure such default) in the payment of rent or additional charges or
in the performance of any of the other terms, covenants or conditions of the
Lease on Lessee's part to be performed, Lessee

                                      G-1
<PAGE>

shall not be disturbed by Lender in its possession of the Leased Premises during
the term of the Lease, or any extension or renewal thereof, or in the enjoyment
of its rights under the Lease.

     3.   If the interest of the Lessor under the Lease shall be acquired by
Lender or any purchaser ("Purchaser") by reason of exercise of the power of sale
or the foreclosure of the Mortgage or other proceedings brought to enforce the
rights of the holder thereof, by deed in lieu of foreclosure or by any other
method, and Lender or Purchaser succeeds to the interest of Lessor under the
Lease, Lessee shall attorn to Lender or Purchaser as its lessor, said attornment
to be

effective and self-operative without the execution of any other instruments on
the part of either party hereto immediately upon Lender's or Purchaser's
succeeding to the interest of the Lessor under the Lease, and the Lease shall
continue in accordance with its terms between Lessee as lessee and Lender or
Purchaser as lessor; provided, however, that:

     (a)  Lender shall not be personally liable under the Lease and Lender's
     liability under the Lease shall be limited to the ownership interest of
     Lender in the Subject Property;

     (b)  Lender shall not be liable for any act or omission of any prior lessor
(including Lessor);

     (c)  Lender shall not be subject to any offsets or defenses which Lessee
might have against any prior lessor (including Lessor);

     (d)  Lender shall not be bound by any prepayment of rent or deposit, rental
security or any other sums deposited with any prior lessor (including Lessor)
under the Lease unless actually received by Lender;

     (e)  Lender shall not be bound by any agreement or modification of the
Lease made without Lender's consent;

     (f)  Lender shall not be bound to commence or complete any construction or
to make any contribution toward construction or installation of any improvements
upon the Leased Premises required under the Lease or any expansion or
rehabilitation of existing improvements thereon, or for restoration of
improvements following any casualty not required to be insured under the Lease
or for the costs of any restorations in excess of any proceeds recovered under
any insurance required to be carried under the Lease; and,

     (g)  Lender shall not be bound by any restriction on competition beyond
the Subject Property.

     4.   Lessee certifies to Lender that the Lease is presently in full force
and effect with no defaults thereunder by the Lessor or by Lessee and unmodified
except as indicated hereinabove; that the term thereof has commenced and the
full rental is now accruing thereunder; that Lessee has accepted possession of
the Leased Premises and that any improvements required by the terms of the Lease
to be made by the Lessor have been completed to the satisfaction of

                                      G-2
<PAGE>

Lessee; that no rent under the Lease has been paid more than thirty (30) days in
advance of its due date; that the address for notices to be sent to Lessee is as
set forth in the Lease, or at the Leased Premises; and that the Lessee, has no
charge, lien, claim or offset under the Lease or otherwise, against rents or
other charges due or to become due thereunder.

     5.   Lessee agrees with Lender that from and after the date hereof, Lessee
will not terminate or seek to terminate the Lease by reason of any act or
omission of the Lessor thereunder until Lessee shall have given written notice,
by registered or certified mail, return receipt requested, of said act or
omission to Lender, which notice shall be addressed to Massachusetts Mutual Life
Insurance Company, C/O David L. Babson and Company Incorporated, 1295 State
Street, Springfield, Massachusetts 01111, Attention: Senior Managing Director,
Real Estate Finance Group, and until a reasonable period of time shall have
elapsed following the giving of such notice, during which period Lender shall
have the right, but shall not be obligated, to remedy such act or omission.

     6.   This Agreement shall inure to the benefit of and shall be binding upon
Lessee and Lender, and their respective heirs, personal representatives,
successors and assigns.  This Agreement may not be altered, modified or amended
except in writing signed by all of the partied hereto.  In the event any one or
more of the provisions contained in this Agreement shall for any reason be held
to be invalid, illegal or unenforceable in any respect, such invalidity,
illegality or unenforceability shall not affect any other provisions of this
Agreement, but this Agreement shall be construed as if such invalid, illegal or
unenforceable provision had never been contained herein.  This Agreement shall
be governed by and construed according to the laws of the State of

                                      G-3
<PAGE>

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed as of the day and year first above written.


[ATTEST OR WITNESSES (2)]           LESSEE:


__________________________________  By _________________________________


__________________________________  Its_________________________________

[SEAL]


[ATTEST OR WITNESSES (2)]           MASSACHUSETTS MUTUAL LIFE
                                    INSURANCE COMPANY
                                    By David L. Babson and Company Incorporated
                                    Its Authorized Agent


__________________________________  By ________________________________

__________________________________  Its_________________________________

[SEAL]

                                      G-4
<PAGE>

                               ACKNOWLEDGEMENTS

STATE OF           )
                   ) ss.
COUNTY OF          )


     On this  , the day of  , 2000, before me, the undersigned party, personally
appeared who acknowledged himself to be the ______ of _________________, a
_________________________ and that he as such bring authorized to do so,
executed the foregoing Lease Subordination, Attornment and Non-Disturbance
Agreement for the purposes therein contained by signing the name of the by
himself as

          IN WITNESS WHEREOF, I hereunto set my hand and official seal.


                                    ____________________________________
                                               Notary Public

My Commissions Expires:



COMMONWEALTH OF MASSACHUSETTS  )
                               ) ss.
COUNTY OF                      )


     On this  , the day of  , 2000, before me, the undersigned party, personally
appeared who acknowledged himself to be the ____________ of David L. Babson and
Company Incorporated the Authorized Agent of MASSACHUSETTS MUTUAL LIFE INSURANCE
COMPANY, a Massachusetts corporation, and that he as such being authorized to do
so, executed the foregoing Lease Subordination, Attornment and Non-Disturbance
Agreement for the purposes therein contained by signing the name of the
corporation by himself as

     IN WITNESS WHEREOF, I hereunto set my hand and official seal.


                                    ___________________________________
                                               Notary Public

My Commission Expires:

                                      G-5
<PAGE>

                                   EXHIBIT H
                                   ---------

                             Letter of Credit Form
                             ---------------------


_________, 2000

200 South Wacker Drive,  L.L.C.
c/o Lend Lease Real Estate Investments, Inc.
455 N. Cityfront Plaza Drive, Suite 3200
Chicago, Illinois, 60611

Attn: ___________________

IRREVOCABLE LETTER OF CREDIT NO. __________

Original Expiration Date:  __________

Gentlemen:

We hereby establish our irrevocable Letter of Credit in your favor for the
account of TenFold Corporation for the sum not exceeding U.S.
__________________________________________ and 00/100 Dollars ($__________).

This Letter of Credit is available against your draft drawn on us bearing the
clause "Drawn Under _________________ Bank, Chicago, Illinois L/C No.
__________________".

We hereby agree with the drawers of the draft drawn and negotiated in compliance
with the terms of this credit, that said draft will be duly honored within
forty-eight (48) hours after it is presented at this office.

It is a condition of this Letter of Credit that it shall be deemed automatically
extended without amendment for a period of one year from the initial expiration
date stated above or any future expiration date hereof, unless at least sixty
(60) days prior to the expiration date we mail you our notice, by registered or
certified mail, informing you that the Letter of Credit will no longer be
automatically renewed beyond the then expiration date.  In the event that we
notify you that it is our intention not to renew this Letter of Credit for an
additional one year period we agree to also notify the following parties by
registered or certified mail:

Lend Lease Real Estate Investments, Inc.
455 North Cityfront Plaza Drive
Suite 3200
Chicago, Illinois 60611
Attn:  Regional Manager

                                      H-1
<PAGE>

and

Lend Lease Real Estate Investments, Inc.
3414 Peachtree Road, N.E.
Atlanta, Georgia 30326
Attention:  Law Department

and

Quarles & Brady LLC
500 West Madison Street
Suite 3700
Chicago, Illinois 60661
Attn:  Peter A. Sarasek, Esq. and Stephanie B. Shellenback, Esq.

This Letter of Credit is transferable and assignable from time to time; any
transfer request shall be effected by presentation to the issuer of the attached
transfer form accompanied by the original of this Letter of Credit, provided
that the holder hereof shall not incur any fees to the issuer as a condition to
any such transfer.

Partial Drawings and reductions are permitted.

Except so far as otherwise expressly stated this documentary credit is subject
to Uniform Customs and Practice for Documentary Credits, 1995 revision, ICC
Publication No. 500, excluding Article 17.

_____________________________________________
Name of Bank

By:__________________________________________

                                      H-2
<PAGE>

                                   EXHIBIT I
                                   ---------

                               Legal Description
                               -----------------

                               200 S. Wacker Dr.
                               Chicago, Illinois


THAT PART OF LOTS 13 AND 14 IN BLOCK 83 IN RESUBDIVISION OF BLOCKS 83, 92 AND
140 IN SCHOOL SECTION ADDITION TO CHICAGO, IN SECTION 16, TOWNSHIP 39 NORTH,
RANGE 14 EAST OF THE THIRD PRINCIPAL MERIDIAN, DESCRIBED AS FOLLOWS:

COMMENCING AT THE NORTH EAST CORNER OF SAID LOT 13; THENCE SOUTH 90 DEGREES WEST
ALONG THE NORTH LINE OF SAID LOT 13 (ALSO BEING THE SOUTH LINE OF WEST ADAMS
STREET), 54.00 FEET TO THE WEST LINE OF WACKER DRIVE, AS DEDICATED, AND THE
PLACE OF BEGINNING OF THE HEREIN DESCRIBED TRACT OF LAND; THENCE SOUTH 0 DEGREES
13 MINUTES 30 SECONDS EAST ALONG SAID WEST LINE OF SOUTH WACKER DRIVE, 166.04
FEET TO THE SOUTH LINE OF SAID LOT 14 (ALSO BEING THE NORTH LINE OF WEST QUINCY
STREET); THENCE NORTH 89 DEGREES 57 MINUTES 40 SECONDS WEST ALONG THE SOUTH LINE
OF SAID LOT 14, 148.00 FEET TO A POINT; THENCE NORTH 9 DEGREES 47 MINUTES 46
SECONDS WEST, 84.20 FEET TO A POINT ON THE NORTH LINE OF SAID LOT 14; THENCE
NORTH 10 DEGREES 27 MINUTES 59 SECONDS WEST, 84.36 FEET TO THE NORTH LINE OF
SAID LOT 13; THENCE NORTH 90 DEGREES EAST ALONG THE NORTH LINE OF SAID LOT 13,
177.00 FEET TO THE PLACE OF BEGINNING, IN COOK COUNTY, ILLINOIS.

                                      I-1
<PAGE>

                                   EXHIBIT J
                                   ---------

                         TERM COMMENCEMENT MEMORANDUM

     THIS TERM COMMENCEMENT MEMORANDUM ("Memorandum") is made as of the ________
day of __________________, 20____, by and between 200 SOUTH WACKER DRIVE,
L.L.C., an Illinois limited liability company ("Landlord") and ________________
______________________________________________________________________
("Tenant").

     1.   Landlord and Tenant are parties to that certain lease dated
________________, 20___ (herein referred to as the "Lease") for premises
described as _________________ ("Premises") located in the building ("Building")
located at 200 South Wacker Drive, Chicago, Illinois, and mutually desire to
enter this Memorandum confirming certain matters relating to the Lease.

     2.   The Term commenced on _______________________, 20___, and such date
shall be deemed the Commencement Date. The Term shall expire on
_______________________, ____, and such date shall be deemed the Termination
Date, unless sooner terminated or extended pursuant to the terms of the Lease.
Tenant's obligations for Base Rent and Additional Rent have commenced or will
commence on ________________, 20___.

     3.   Any work and improvements required to be performed by Landlord under
the Lease to prepare the Premises for initial occupancy have been completed
satisfactorily, the Premises are tenantable and suitable for the permitted use
under the Lease, the Premises and Building are satisfactory in all respects
except as noted in the punchlist attached hereto as Appendix I, Tenant is in
possession of the Premises, the Lease is in full force and effect and has not
been modified, altered or amended, Landlord has fulfilled all obligations and is
not in default under the Lease, and there are no offsets or credits against
Rent.

                                      J-1
<PAGE>

     4.   Capitalized terms not otherwise defined herein shall have the meanings
ascribed thereto in the Lease.



                                    LANDLORD:

                                    200 SOUTH WACKER DRIVE, L.L.C.

                                    By:  The Equitable Life Assurance Society of
                                         the United States, a New York
                                         corporation, solely on behalf and for
                                         the benefit of its Separate Account 8,
                                         known as the "Prime Property Fund"



                                         By: ____________________________
                                         Name:  John Schoser
                                         Its:  Investment Officer


ATTEST:                             TENANT:

                                    ____________________________________
                                    a _____________________ corporation

By:____________________________
   Its:________________________

                                    By:_______________________________
                                       Its: __________________________

                                      J-2