<PAGE>

                                                               EXHIBIT 10.15

            --------------------------------------------------------
                                   UNION TOWER
            ---------------------------------------------------------

                                  OFFICE LEASE

                                     BETWEEN

                        UNION TOWER INVESTORS II, L.L.C.,
                      A DELAWARE LIMITED LIABILITY COMPANY

                                    LANDLORD

                                       AND

                              PARTICIPATE.COM, INC.
                             A DELAWARE CORPORATION

                                     TENANT

                             DATED FEBRUARY 9, 2000


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                                TABLE OF CONTENTS
<TABLE>

<S>                                                                          <C>
ARTICLE 1

PREMISES AND TERM..............................................................1

ARTICLE 2

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

ARTICLE 3

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

ARTICLE 4

COMMENCEMENT OF TERM...........................................................5

ARTICLE 5

CONDITION OF PREMISES..........................................................5

ARTICLE 6

USE AND RULES .................................................................5

ARTICLE 7

SERVICES AND UTILITIES ........................................................6

ARTICLE 8

ALTERATIONS AND LIENS .........................................................9

ARTICLE 9

REPAIRS ......................................................................11

ARTICLE 10

CASUALTY DAMAGE ..............................................................11

ARTICLE 11

INSURANCE, SUBROGATION, AND WAIVER OF CLAIMS .................................13
<PAGE>

ARTICLE 12

CONDEMNATION .................................................................14

ARTICLE 13

RETURN OF POSSESSION .........................................................15

ARTICLE 14

HOLDING OVER .................................................................16

ARTICLE 15

NO WAIVER ....................................................................16

ARTICLE 16

ATTORNEYS' FEES AND JURY TRIAL ...............................................17

ARTICLE 17

PERSONAL PROPERTY TAXES, RENT TAXES AND OTHER TAXES ..........................17

ARTICLE 18

REASONABLE APPROVALS .........................................................17

ARTICLE 19

SUBORDINATION, ATTORNMENT AND MORTGAGEE PROTECTION............................17

ARTICLE 20

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

ARTICLE 21

ASSIGNMENT AND SUBLETTING ....................................................19

ARTICLE 22

RIGHTS RESERVED BY LANDLORD ..................................................22

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ARTICLE 23

LANDLORD'S REMEDIES ..........................................................23

ARTICLE 24

LANDLORD'S RIGHT TO CURE .....................................................27

ARTICLE 25

CAPTIONS, DEFINITIONS AND SEVERABILITY .......................................28

ARTICLE 26

CONVEYANCE BY LANDLORD AND LIABILITY .........................................33

ARTICLE 27

INDEMNIFICATION ..............................................................33

ARTICLE 28

SAFETY AND SECURITY DEVICES, SERVICES AND PROGRAMS............................34

ARTICLE 29

COMMUNICATIONS AND COMPUTER LINES ............................................34

ARTICLE 30

HAZARDOUS MATERIALS ..........................................................36

ARTICLE 31

MISCELLANEOUS ................................................................38

ARTICLE 32

OFFER ........................................................................39

ARTICLE 33

NOTICES ......................................................................39

<PAGE>

ARTICLE 34

REAL ESTATE BROKERS ..........................................................39

ARTICLE 35

SECURITY DEPOSIT .............................................................40

ARTICLE 36

AMERICANS WITH DISABILITIES ACT...............................................41

ARTICLE 37

OPTION TO EXTEND .............................................................42

ARTICLE 38

SIGNS ........................................................................44

ARTICLE 39

PARKING / GENERATOR ..........................................................46

ARTICLE 40

TERMINATION OPTION ...........................................................48

ARTICLE 41

EXPANSION OPTION .............................................................48

ARTICLE 42

ENTIRE AGREEMENT .............................................................50

</TABLE>

RIDER ONE

EXHIBIT A - BASE RENT
EXHIBIT B - EXCLUSIONS FROM OPERATING EXPENSES
EXHIBIT C - FORM OF LETTER OF CREDIT
EXHIBIT D - CLEANING AND JANITORIAL SPECIFICATIONS
EXHIBIT E - COMMENCEMENT DATE AND EXPIRATION DATE CONFIRMATION

WORK AGREEMENT

<PAGE>

                                  OFFICE LEASE

         THIS LEASE made as of the 9th day of February, 2000 (the "EFFECTIVE
DATE"), between UNION TOWER INVESTORS II, L.L.C., a Delaware limited
liability company ("Landlord"), and PARTICIPATE.COM, INC. a Delaware
corporation ("TENANT"), whose address is 945 West George Street, Chicago,
Illinois 60657.

                                   WITNESSETH:

                                    ARTICLE 1
                                PREMISES AND TERM


         Landlord hereby leases to Tenant and Tenant hereby leases from Landlord
that certain space (the "PREMISES") consisting of the entire rentable area on
the sixteenth (16th) floor (consisting of 20,667 rentable square feet) (the
"SIXTEENTH FLOOR PREMISES") and the entire rentable area on the seventeenth
(17th) floor (consisting of 20,667 rentable square feet) (the "SEVENTEENTH FLOOR
PREMISES"), in the building known as Union Tower (the "BUILDING"), located at
550 West Van Buren Street, Chicago, Illinois (the "PROPERTY," as further
described in Article 25), subject to the provisions herein contained. The term
of this Lease (the "TERM") shall commence on the Sixteenth Floor Commencement
Date (as hereafter defined) (the "COMMENCEMENT DATE"). If Tenant does not
exercise the Expansion Option (as defined in Article 41), the Term shall end on
the date that is the last day of the 120th full calendar month following the
Commencement Date, unless sooner terminated as provided herein. If Tenant
exercises the Expansion Option (as defined in Article 41), the Term shall end on
the date that is the last day of the 120th full calendar month following the
Expansion Space Commencement Date (as defined in Article 41), unless sooner
terminated as provided herein. The applicable date on which this Lease ends is
referred to herein as the "EXPIRATION DATE,"

         The term of this Lease with respect to the Sixteenth Floor Premises
shall commence on the date (the "SIXTEENTH FLOOR COMMENCEMENT DATE") which is
the earlier to occur of (i) the "sixteenth floor delivery date," or (ii)
"Substantial Completion" of the "Sixteenth Floor Work" (as such terms are
defined in the Work Agreement between Landlord and Tenant, entered into
contemporaneously herewith). The Term of this Lease with respect, to the
Seventeenth Floor Premises shall commence on the date (the Seventeenth Floor
Commencement Date") which is the earlier to occur of (i) the "SEVENTEENTH FLOOR
DELIVERY DATE," or (ii) "Substantial Completion" of the "Seventeenth Floor
Work" (as such terms are defined in the Work Agreement). Promptly after
Landlord Substantially Completes the Sixteenth Floor Work and the Seventeenth
Floor Work, Landlord and Tenant shall execute and deliver to each other a
supplement to this Lease in the form attached as EXHIBIT E confirming the
Commencement Date and Expiration Date. If Tenant exercises the Expansion Option,
then promptly after Landlord Substantially Completes the "Expansion Space Work"
(as defined in Article 41), Landlord and Tenant


                                       1
<PAGE>

shall execute and deliver to each other an additional supplement to this Lease
in the form attached as Exhibit E confirming the Commencement Date and revised
Expiration Date.

         Landlord and Tenant agree that for purposes of this Lease, the rentable
area of the Premises is 41,334 square feet and the rentable area of the Property
is 332,608 square feet. The rentable area of the Premises shall increase to
62,001 square feet in the event that Tenant exercises the Expansion Option (as
defined in Article 41).

                                    ARTICLE 2
                                    BASE RENT

         Tenant shall pay Landlord Base Rent as set forth in EXHIBIT A attached
hereto, in monthly installments, in advance on or before the first day of each
calendar month during the Term, except that Base Rent for the first full
calendar month for which Base Rent shall be due, shall be paid when Tenant
executes this Lease. If the Commencement Date is a day other than the first day
of a calendar month, or if the Term ends on a day other than the last day of a
calendar month, then the Base Rent for such month shall be prorated by
multiplying the then applicable monthly Base Rent by a fraction, the numerator
of which is the number of days in the partial month included in the Term and the
denominator of which is 30.

                                    ARTICLE 3
                                 Additional Rent

         (A) TAXES. Tenant shall pay Landlord an amount equal to Tenant's
Prorata Share of Taxes in excess of the amount of Taxes paid by Landlord during
the calendar year 2000 ("BASE TAX YEAR"). The terms "TAXES" and "TENANTS PRORATA
SHARE" shall have the meanings specified therefor in Article 25.

         (B) OPERATING EXPENSES. Tenant shall pay Landlord an amount equal to
Tenant's Prorata Share of Operating Expenses in excess of the amount of
Operating Expenses paid by Landlord during the calendar year 2000 ("BASE EXPENSE
YEAR"). The term "OPERATING EXPENSES" shall have the meaning specified therefor
in Article 25.

         (C) MANNER OF PAYMENT. Taxes and Operating Expenses shall be paid in
the following manner:

            (i)   Landlord may reasonably estimate in advance the amounts Tenant
                  shall owe for Taxas and Operating Expenses for any full or
                  partial calendar year of the Term; provided that no such
                  estimated payments shall be payable until the calendar year
                  2001. In such event, Tenant shall pay such estimated amounts,
                  on a monthly basis, on or before the first day of each
                  calendar month, together with Tenant's payment of Base Rent.
                  Such estimate may be reasonably adjusted from time


                                       2
<PAGE>


                  to time by Landlord, but not more than one (1) time in any
                  calendar year and only upon thirty (30) days prior written
                  notice to Tenant.

            (ii)  Within one hundred twenty (120) days after the end of each
                  calendar year, or as soon thereafter as practicable, Landlord
                  shall provide a statement (the "STATEMENT") to Tenant showing:
                  (a) the amount of actual Taxes and Operating Expenses for such
                  calendar year, with a listing of amounts for major categories
                  of Operating Expenses, and such amounts for the Base Year, (b)
                  any amount paid by Tenant towards Taxes and Operating Expenses
                  during such calendar year on an estimated basis, and (c) any
                  revised estimate of Tenant's obligations for Taxes and
                  Operating Expenses for the current calendar year as reasonably
                  determined by Landlord.

            (iii) If the Statement shows that Tenant's estimated payments were
                  less than Tenant's actual obligations for Taxes and Operating
                  Expenses for such year, Tenant shall pay the difference. If
                  the Statement shows an increase in Tenant's estimated payments
                  for the current calendar year, Tenant shall pay the difference
                  between the new and former estimates, for the period of
                  January 1 of the current calendar year through the month in
                  which the Statement is sent. Tenant shall make such payments
                  within thirty (30) days after Landlord sends the Statement.

            (iv)  If the Statement shows that Tenant's estimated payments
                  exceeded Tenant's actual obligations for Taxes and Operating
                  Expenses, Tenant shall receive a credit for the difference
                  against payments of Rent next due. If the Term shall have
                  expired and no further Rent shall be due, Tenant shall receive
                  a refund of such difference, within thirty (30) days after
                  Landlord sends the Statement.

            (v)   So long as Tenant's obligations hereunder are not adversely
                  affected thereby, Landlord reserves the right to reasonably
                  change, from time to time, the manner or timing of the
                  foregoing payments. In lieu of providing one Statement
                  covering Taxes and Operating Expenses, Landlord may provide
                  separate statements, at the same or different times. No delay
                  by Landlord in providing the Statement (or separate
                  statements) shall be deemed a default by Landlord or a waiver
                  of Landlord's right to require payment of Tenant's obligations
                  for actual or estimated Taxes or Operating Expenses. In no
                  event shall a decrease in Taxes or Operating Expenses below
                  the Base Year amounts ever decrease the monthly Base Rent, or
                  give rise to a credit in favor of Tenant. All Statement (or
                  separate statements) must be delivered to Tenant within three
                  (3) years from the end of the applicable calendar in which
                  such amounts are inccured.

                                       3

<PAGE>


         (D) PRORATION. If the Term commences other than on January 1, or ends
other than on December 31, Tenant's obligations to pay estimated and actual
amounts towards Taxes and Operating Expenses for such first or final calendar
years shall be prorated to reflect the portion of such years included in the
Term. Such proration shall be made by multiplying the total estimated or actual
(as the case may be) Taxes and Operating Expenses, for such calendar years by a
fraction, the numerator of which shall be the number of days of the Term during
such calendar year, and the denominator of which shall be 365.

         (E) LANDLORD'S RECORDS. Landlord shall maintain records respecting
Taxes and Operating Expenses and determine the same in accordance with generally
accepted accounting principles, consistently applied. Although this Lease
contemplates the computation of Taxes and Operating Expenses on a cash basis,
Landlord shall make reasonable and appropriate accrual adjustments to ensure
that each calendar year includes substantially the same recurring items.
Landlord reserves the right to change to a full accrual system of accounting so
long as the same is consistently applied and Tenant's obligations are not
adversely affected. Tenant or its representative shall have the right to examine
such records, including records for the Base Year, upon reasonable prior notice
specifying such records Tenant desires to examine, during normal business hours
at the place or places where such records are normally kept (provided that such
records shall be kept in, or made available for Tenant's review in, Chicago,
Illinois) by sending such notice no later than ninety (90) days following the
furnishing of the Statement. Tenant may take exception to matters included in
Taxes or Operating Expenses, or Landlord's computation of Tenant's Prorata Share
of either, by sending notice specifying such exception and the reasons therefor
to Landlord within thirty (30) days after Tenant completes its audit, but in no
event later than ninety (90) days after Landlord furnishes the Statement. Such
Statement shall be considered final, except as to matters to which exception is
taken after examination of Landlord's records in the foregoing manner and within
the foregoing times. Tenant acknowledges that Landlord's ability to budget and
incur expenses depends on the finality of such Statement, and accordingly agrees
that time is of the essence of this Paragraph. If Tenant takes exception to any
matter contained in the Statement as provided herein, Landlord shall refer the
matter to an independent certified public accounting firm designated by
Landlord, which firm shall not have prepared the Statement, whose certification
as to the proper amount shall be final and conclusive as between Landlord and
Tenant. Tenant shall promptly pay the cost of such certification unless such
certification determines that Tenant was overbilled by more than three percent
(3%), in which event Landlord shall pay the cost of such certification. If such
certification indicates that the amount actually paid by Tenant, in relation to
a matter for which Tenant has taken exception pursuant to this Paragraph,
exceeds the amount Tenant should have paid, then Landlord shall credit the
difference against the then next due payments to be made by Tenant under this
Article 3, or if the Lease has expired, such amount shall be refunded to Tenant
within thirty (30) days of such certification. Pending resolution of any such
exceptions in the foregoing manner, Tenant shall continue paying Tenant's
Prorata Share of Taxes and Operating Expenses in the amounts determined by
Landlord, subject to adjustment after any such exceptions are so resolved.

                                       4
<PAGE>

         In the event that a tenant of the Building other than Tenant performs
an audit of Landlord's books and records regarding such tenant's prorata share
of Taxes or Operating Expenses, and such audit reveals that Landlord made an
error in the computation of an item of Taxes or Operating Expenses, and
provided that (1) such error was not de minimis, and (2) tenants of the
Building, including Tenant, pay their Prorata Share of the item of Taxes or
Operating Expenses that is the subject of such error on the same basis as the
tenant that performed the audit, then Landlord shall adjust Tenant's Prorata
Share of such item in the same manner as adjusted for the tenant that performed
the audit, whether increased or decreased.

         (F) RENT AND OTHER CHARGES. Base Rent, Taxes, Operating Expenses and
any other amounts which Tenant is or becomes obligated to pay Landlord under
this Lease or other agreement entered into in connection herewith, are sometimes
herein referred to collectively as "Rent," and all remedies applicable to the
non-payment of Rent shall be applicable thereto. Rent shall be paid at any
office maintained by Landlord or its agent at the Property, or at such other
place as Landlord may designate in writing with reasonable notice to Tenant.

                                    ARTICLE 4
                              COMMENCEMENT OF TERM

         The Commencement Date is set forth in Article 1. During any period that
Tenant shall be permitted to enter the Premises prior to the Commencement Date,
other than to occupy the same (E.G., to perform alterations or improvements),
Tenant shall comply with all terms and provisions of this Lease, except those
provisions requiring the payment of Rent.


                                    ARTICLE 5
                              CONDITION OF PREMISES

         Tenant agrees to accept the Premises, Property, Systems and Equipment
(as defined in Article 25) "as is," except for latent defects, without any
agreements, representations, understandings or obligations on the part of
Landlord to perform any alterations, repairs or improvements except as expressly
set forth in this Lease or the Work Agreement.


                                    ARTICLE 6
                                  USE AND RULES

         Tenant shall use the Premises for general office purposes and no other
purpose whatsoever, in compliance with all applicable Laws, and without
disturbing or interfering with any other tenant or occupant of the Property.
Tenant will comply with all Laws

                                       5

<PAGE>

regulations and other requirements, including without limitation, environmental,
health, safety and police requirements and regulations respecting the Premises,
now or hereinafter in force, at its sole cost, and will not use the Premises for
any immoral purposes; provided, however, that Tenant shall not be obligated to
make any structural or capital improvements to the Premises in order to comply
with any particular Law unless such Law is applicable to the Premises due to
Tenant's specific use thereof. Tenant shall not use the Premises in any manner
so as to cause a cancellation of Landlord's insurance policies, or an increase
in the premiums thereunder. Tenant shall comply with all rules set forth in
Rider One attached hereto (the "RULES"). Landlord shall have the right to
reasonably amend such Rules and supplement the same with other reasonable Rules
(not expressly inconsistent with this Lease) relating to the Property, or the
promotion of safety, care, cleanliness or good order therein, and all such
amendments or new Rules shall be binding upon Tenant after five (5) days notice
thereof to Tenant, provided that any amendment or supplement to the Rules does
not materially and adversely affect any of Tenant's rights under this Lease. All
Rules shall be applied on a non-discriminatory basis, but nothing herein shall
be construed to give Tenant or any other Person (as defined in Article 25) any
claim, demand or cause of action against Landlord arising out of the violation
of such Rules by any other tenant, occupant, or visitor of the Property, or out
of the enforcement or waiver of the Rules by Landlord in any particular
instance. In the event of any conflict between the terms of this Lease and the
Rules, the terms of this Lease shall govern.

                                    ARTICLE 7
                             SERVICES AND UTILITIES

         Landlord shall provide the following services and utilities (the cost
of which shall be included in Operating Expenses unless otherwise stated herein
or in any separate rider hereto):

         (A) Heat and air-conditioning from 7:00 a.m. until 6:00 p.m. Monday
through Friday, except on Holidays (as defined in Article 25), and on Saturdays
from 8:00 a.m. until 1:00 p.m. The Building standard heating, ventilating and
air conditioning system is set forth in Exhibit C to the Work Agreement, and
Landlord shall maintain the system in accordance therewith, subject to
adjustments pursuant to mandatory and voluntary compliance by Landlord with Laws
relating to energy use. Landlord shall not be responsible for inadequate
air-conditioning or ventilation to the extent the same occurs because Tenant
uses any item of equipment consuming more than 500 watts at rated capacity
without providing adequate air-conditioning and ventilation therefor. Whenever
heat generating machines or equipment installed by Tenant affect the temperature
otherwise maintained by Landlord in the Premises, or whenever the occupancy or
electrical load exceeds the air conditioning standards set forth by Landlord,
Landlord shall be relieved of responsibility for maintaining such standards and
in such event Tenant shall, promptly, following delivery of written notice by
Landlord to Tenant, either (i) discontinue use of such heat generating machines
or equipment, or (ii) install supplementary air conditioning units in the
Premises, the cost, installation, operation and maintenance of

                                       6
<PAGE>

which shall be paid by Tenant to Landlord at such rates as Landlord generally
charges tenants in the Building from time to time, which rates shall be
available in the office of the Building. Tenant has requested, and Landlord has
consented to, the installation of a supplemental HVAC unit for the Sixteenth
Floor Premises, the size of which shall be subject to Landlord's reasonable
approval and the installation of which shall be performed in accordance with
plans approved in advance by Landlord. The maximum available amount of
supplemental air conditioning capacity that is connected to the Building's
condenser water riser and available to Tenant for such supplemental HVAC unit is
15 tons per full floor of the Premises. Tenant may re-allocate a portion of the
supplemental air conditioning capacity that is available to the Premises toward
a particular floor of the Premises, provided that in no event may Tenant's
allocation of supplemental air conditioning capacity to a single floor of the
Premises exceed thirty (30) tons. Tenant will cooperate with Landlord and abide
by all regulations and requirements which Landlord may prescribe for the proper
functioning of the ventilating and air conditioning systems.

         (B) Water for drinking, lavatory and toilet purposes at those points of
supply provided for nonexclusive general use of other tenants at the Property.

         (C) Customary office cleaning and trash removal service, Monday through
Friday evenings, in and about the Premises, in accordance with the Cleaning and
Janitorial Specifications attached hereto as Exhibit D.

         (D) Operatorless passenger elevator service and freight elevator
service (subject to scheduling by Landlord) in common with Landlord and other
tenants and their contractors, agents and visitors.

         (E) Tenant shall have access to the Building twenty-four (24) hours per
day, seven (7) days per week. After normal business hours, access to the
Building will be provided using a key card or other similar access and
monitoring system. A security representative of Landlord will be at the Property
twenty-four (24) hours per day, seven (7) days per week.

         (F) Landlord shall seek to provide such extra utilities or services
as Tenant may from time to time request, if the same are reasonable and
feasible for Landlord to provide and do not involve modifications or
additions to the Property or existing Systems and Equipment (as defined in
Article 25), and if Landlord shall receive Tenant's request within a
reasonable period prior to the time such extra utilities or services are
required. Landlord may comply with written or oral requests by any officer or
employee of Tenant, unless Tenant shall notify Landlord of, or Landlord shall
request, the names of authorized individuals (up to 3 for each floor on which
the Premises are located) and procedures for written requests. Tenant shall,
for such extra utilities or services, pay the rates that Landlord generally
charges tenants in the Building for such utilities or services, which rates
shall be available in the office of the Building and are subject to
adjustment from time to time. All charges for such extra utilities or
services shall be due at the same time as the installment of Base Rent with
which the same are billed, or if billed separately, shall be due within
thirty (30) days after such billing. In the event Tenant shall

                                       7
<PAGE>

fail to make payment for such additional services, Landlord may, in addition to
all other remedies which Landlord may have for the non-payment of Rent and
without notice to Tenant, discontinue any or all such additional services, and
such discontinuance shall not be held or pleaded as an eviction or as a
disturbance in any manner whatsoever of Tenant's possession, or relieve Tenant
from the payment of Rent when due, or vary or change any other provision of this
Lease, or render Landlord liable for damages of any kind whatsoever.

         At Tenant's sole cost and expense, the Premises shall be separately
metered and Tenant shall pay directly to the utility company all electricity
charges with respect to Tenant's electrical consumption within the Premises.
Tenant's use of electrical service shall not exceed the safe and lawful capacity
of the Building's existing electrical circuits, which are designed to and shall
provide a total of 7.5 watts per rentable square foot for all Tenant
requirements, including lighting, outlets and supplemental air conditioning. In
the event that Tenant requires HVAC service outside of the normal Building hours
set forth in Article 7(A) above, Landlord shall seek to provide same, provided
that Landlord shall receive Tenant's request within a reasonable period prior to
the time such extra HVAC service is needed. Landlord may comply with written or
oral requests by any officer or employee of Tenant. Tenant shall pay the rates
that Landlord generally charges tenants in the Building for such extra HVAC
service, which rates shall be available in the office of the Building and are
subject to adjustment from time to time. All charges for extra HVAC service
shall be due at the same time as the installment of Base Rent with which the
same are billed, or if billed separately, shall be due within thirty (30) days
after such billing. Landlord's current charges for extra HVAC service are $50 to
$60 per hour. Tenant shall pay for the cost of all supplemental air conditioning
capacity used by Tenant based on the rates that Landlord generally charges
tenants in the Building for such usage, which rates shall be available in the
office of the Building and are subject to adjustment from time to time.
Landlord's current charges for supplemental air conditioning capacity is $30 per
ton per month. Alternatively, Tenant may pay for supplemental air conditioning
capacity based upon Tenant's actual usage thereof as determined through Tenant's
installation of a meter off the riser that measures Tenant's use thereof.

         Landlord agrees to operate and maintain the Building in accordance with
the standard of other comparable first-class office buildings in the Chicago
loop area.

         Landlord does not warrant that any services or utilities will be free
from shortages, failures, variations, or interruptions caused by repairs,
maintenance, replacements, improvements, alterations, changes of service,
strikes, lockouts, labor controversies, accidents, inability to obtain services,
fuel, stream, water or supplies, governmental requirements or requests, or other
causes beyond Landlord's reasonable control. None of the same shall be deemed an
eviction or disturbance of Tenant's use and possession of the Premises or any
part thereof, or render Landlord liable to Tenant for abatement of Rent, or
relieve Tenant from performance of Tenant's obligations under this Lease.
Landlord in no event shall be liable for damages by reason of loss of profits,
business interruption or other consequential damages.

                                       8
<PAGE>

         Notwithstanding anything to the contrary in the Lease, in the event
that there shall be an interruption, curtailment or suspension of the Building's
elevator, electricity or HVAC service or water supply in the manner required to
be provided in this Article 7 (and no reasonably equivalent alternative service
or supply is provided by Landlord and Tenant is unable to and does not use the
Premises or more than 20,000 rentable square feet of the Premises as a result of
such interruption, curtailment or suspension (a "SERVICE INTERRUPTION"), and if
(i) such Service Interruption shall not have been caused, in whole or in part,
by an act or omission or negligence of Tenant, or of Tenant's agents, employees,
contractors or visitors, (ii) such Service Interruption does not arise as a
result of a matter, event or condition affecting the general area in which the
Property is located, such as a city-wide power outage, and (iii) Tenant shall
have given written notice respecting such Service Interruption to Landlord, such
Service Interruption continues for more than five (5) consecutive business days
after Landlord receives such notice, Rent hereunder shall thereafter be abated
in the same proportion as the portion of the Premises affected by the Service
Interruption bears to the entire Premises from the end of such five (5)
consecutive business day period until such time as such services or utilities
are restored or Tenant begins using the Premises (or affected portion thereof)
again for the conduct of Tenant's business, whichever shall first occur. If a
Service Interruption occurs and if (i) such Service Interruption shall not have
been caused, in whole or in part, by an act or omission or negligence of
Tenant, or of Tenant's agents, employees, contractors or visitors, and (ii) such
Service Interruption does not arise as a result of a matter, event or condition
affecting the general area in which the Property is located, such as a city-wide
power outage, Tenant may terminate this Lease if Landlord fails to
substantially complete the cure of such Service Interruption within one hundred
twenty (120) days after commencing the same, subject to extension due to force
majeure (as defined in Article 10), provided that such extension for force
majeure shall not exceed thirty (30) days. In order to exercise the foregoing
termination right, Tenant must send Landlord written notice of termination
specifying the basis for termination at any time after the expiration of the 120
day period (as the same may be extended by reason of force majeure) described in
the preceding sentence. Such termination right shall not be available to Tenant
if Landlord substantially completes the cure of such Service Interruption prior
to receiving Tenant's termination notice. Such abatement of Rent and termination
right shall be Tenant's sole recourse in the event of a Service Interruption.

                                    ARTICLE 8
                              ALTERATIONS AND LIENS

         Tenant shall make no additions, changes, alterations or improvements
(the "WORK") to the Premises or the Systems and Equipment (as defined in
Article 25) pertaining to the Premises without the prior written consent of
Landlord, which consent will not be unreasonably withheld, conditioned or
delayed, as long as any proposed additions, changes, alterations or
improvements do not affect the Systems and Equipment or the structure of the
Property and as long as Tenant complies with the other requirements of this
Article 8. Although Tenant must comply with the other provisions of this
Article 8,

                                       9
<PAGE>

Tenant must provide prior notice to Landlord, but need not obtain Landlord's
consent, as a condition of performing (a) cosmetic improvements such as
painting or re-carpeting, or (b) additions, changes, alterations or
improvements that do not affect the Systems and Equipment or the structure of
the Property and which cost less than $25,000 in the aggregate. Landlord may
impose reasonable requirements as a condition of such consent including
without limitation the submission of plans and specifications for Landlord's
prior written approval, obtaining necessary permits, posting bonds, obtaining
insurance, prior approval of contractors, subcontractors and suppliers, prior
receipt of copies of all contracts and subcontracts, contractor and
subcontractor lien waivers, affidavits listing all contractors,
subcontractors and suppliers, use of union labor (if Landlord uses union
labor), affidavits from engineers reasonably acceptable to Landlord stating
that the Work will not adversely affect the Systems and Equipment or the
structure of the Property, and reasonable requirements as to the manner and
times in which such Work shall be done. All Work shall be performed in a good
and workmanlike manner and all materials used shall be of a quality
comparable to or better than those in the Premises and Property and shall be
in accordance with plans and specifications approved by Landlord, and
Landlord may require that all such Work be performed under Landlord's
supervision. In all cases, Tenant shall pay Landlord's out-of-pocket expenses
incurred in connection with Landlord's review of Tenant's plans and
specifications and Landlord's supervision of the Work. If Landlord consents
or supervises, the same shall not be deemed a warranty as to the adequacy of
the design, workmanship or quality of materials, and Landlord hereby
expressly disclaims any responsibility or liability for the same. Landlord
shall under no circumstances have any obligation to repair, maintain or
replace any portion of the Work, unless the necessity for such repair,
maintenance or replacement is due to the negligence or willful misconduct of
Landlord or its agents or their respective employees or contractors.

         Tenant shall keep the Property and Premises free from any mechanic's,
materialman's or similar liens or other such encumbrances in connection with any
Work on or respecting the Premises not performed by or at the request of
Landlord, and shall indemnify and hold Landlord harmless from and against any
claims, liabilities, judgments, or costs (including attorneys' fees) arising out
of the same or in connection therewith.  Tenant shall give Landlord notice at
least ten (10) days prior to the commencement of any Work on the Premises (or,
if applicable, such additional time as may be necessary under applicable Laws to
afford Landlord the opportunity of posting and recording appropriate notices of
non-responsibility). Within thirty (30) days after written notice by Landlord of
the existence of a lien, Tenant shall either (i) cause the lien to be released
and removed of record, (ii) provide Landlord with endorsements (reasonably
acceptable to Landlord and any Holder) to Landlord's and Holder's title
insurance policies insuring against the enforcement of such lien, or (iii)
provide Landlord with a bond from a company reasonably satisfactory to Landlord
and in form, substance and amount reasonably satisfactory to Landlord, insuring
against loss arising from the enforcement of such lien. If Tenant shall fail to
take any of the foregoing actions, Landlord may pay the amount necessary to
remove such lien or encumbrance, without being responsible for investigating the
validity thereof. The amount so paid shall be deemed additional Rent under this
Lease payable upon demand, without limitation as to other remedies available to
Landlord under this Lease. Nothing contained in this Lease shall authorize
Tenant to do any act which shall

                                       10
<PAGE>

subject Landlord's title to the Property or Premises to any liens or
encumbrances whether claimed by operation of law or express or implied contract.
To the fullest extent permitted by applicable Law, any claim to a lien or
encumbrance upon the Property or Premises arising in connection with any Work on
or respecting the Premises not performed by or at the request of Landlord shall
be null and void, or at Landlord's option shall attach only against Tenant's
interest in the Premises and shall in all respects be subordinate to Landlord's
title to the Property and Premises.

                                    ARTICLE 9
                                     REPAIRS

         Except for customary cleaning and trash removal provided by Landlord
under Article 7, and damage covered under Article 10, Tenant shall keep the
Premises in good and sanitary condition, working order and repair (including
without limitation, carpet, wallcovering, doors, plumbing and other fixtures,
equipment, alterations and improvements whether installed by Landlord or
Tenant). In the event that any repairs, maintenance or replacements are
required, Tenant shall promptly arrange for the same either through Landlord for
such reasonable charges as Landlord may from time to time establish, or such
contractors as Landlord generally uses at the Property or such other contractors
as Landlord shall first reasonably approve in writing, and in a first class,
workmanlike manner. If Tenant does not with reasonable promptness make such
arrangements, Landlord may, after reasonable prior notice to Tenant, but need
not, make such repairs, maintenance and replacements, and the actual
out-of-pocket costs paid or incurred by Landlord therefor shall be reimbursed by
Tenant promptly after request by Landlord (such request to be accompanied by
supporting documentation in reasonable detail). Tenant shall indemnify Landlord
and pay for any repairs, maintenance and replacements to areas of the Property
outside the Premises, the Systems or Equipment, caused, in whole or in part, as
a result of moving any furniture, fixtures, or other property to or from the
Premises, or by Tenant or its employees, agents, contractors, or visitors.
Except as provided in the preceding sentence, or for damage covered under
Article 10, Landlord shall keep the common areas, the Systems and Equipment and
the structural portions of the Property in good and sanitary condition, working
order and repair, and in general compliance with all applicable laws, rules and
regulations and in accordance with the standard of other comparable first-class
office buildings in the Chicago loop area (the cost of which shall be included
in Operating Expenses, as described in Article 25, except as limited therein).

                                   ARTICLE 10
                                 CASUALTY DAMAGE

         If the Premises or any common areas of the Property providing access
thereto shall be damaged by fire or other casualty, and if such casualty does
not cause a termination of this Lease as hereinafter provided, Landlord shall
use available insurance proceeds to restore the same. Such restoration shall be
to substantially the condition prior to the casualty, except for modifications
required by zoning and building codes and other Laws,

                                       11
<PAGE>

any other modifications to the common areas deemed desirable by Landlord
(provided access to the Premises is not materially impaired) or required by any
Holder (as defined in Article 25), and except that Landlord shall not be
required to repair or replace any of Tenant's furniture, furnishings, fixtures
or equipment, or any alterations or improvements in excess of any work performed
or paid for by Landlord under any separate agreement signed by the parties in
connection herewith. Landlord shall not be liable for any inconvenience or
annoyance to Tenant or its visitors, or injury to Tenant's business resulting in
any way from such damage or the repair thereof. However, Landlord shall allow
Tenant a proportionate abatement of Rent during the time and to the extent the
Premises are unfit for occupancy for the conduct of Tenant's business and not
occupied by Tenant for the conduct of Tenant's business as a result thereof
(unless Tenant or its employees or agents caused the damage). Notwithstanding
the foregoing to the contrary, Landlord may elect to terminate this Lease by
notifying Tenant in writing of such termination within sixty (60) days after the
date of damage (such termination notice to include a termination date providing
at least ninety (90) days for Tenant to vacate the Premises), if the Property
shall be materially damaged by Tenant or its employees or agents, or if the
Property shall be damaged by fire or other casualty or cause such that: (a)
repairs to the Premises and access thereto cannot reasonably be completed within
one hundred fifty (150) days after the casualty without the payment of overtime
or other premiums, (b) more than forty percent (40%) of the Premises is affected
by the damage, and fewer than 18 months remain in the Term, or any material
damage occurs to the Premises during the last 12 months of the Term, (c) any
Holder (as defined in Article 25) shall require that the insurance proceeds or
any portion thereof be used to retire the Mortgage debt (or shall terminate the
ground lease, as the case may be), or the damage is not fully covered by
Landlord's insurance policies, or (d) the cost of the repairs, alterations,
restoration or improvement work would exceed forty percent (40%) of the
replacement value of the Building. Tenant agrees that Landlord's obligation to
restore, and the abatement of Rent provided herein, shall be Tenant's sole
recourse in the event of such damage, and, except as provided below in this
Article 10, Tenant waives any other rights Tenant may have under any applicable
law to terminate the Lease by reason of damage to the Premises or Property.
Tenant acknowledges that this Article represents the entire agreement between
the parties respecting damage to the Premises or Property.

         Notwithstanding anything to the contrary contained in this Article 10,
Tenant may terminate this Lease if Tenant is unable to use all or a substantial
portion of the Premises for the conduct of Tenant's business as a result of fire
or other casualty not caused by Tenant or its employees or agents, and (a)
Landlord fails to commence, restoration work to the Premises within sixty (60)
days after the damage occurs, or (b) Landlord fails to substaintially complete
such work within one hundred fifty (150) days after the date of such casualty,
or such additional time as may be necessary due to strikes, lock-outs or other
labor troubles, shortages of equipment or materials, governmental requirements,
power shortages or outages or other causes beyond Landlord's reasonable control
(collectively, "FORCE MAJEURE"), which time period for events of force majeure
shall in no event exceed, in the aggregate, more than one hundred and twenty
(120) days, or (c) such work is reasonably estimated (which estimate Landlord
shall provide to Tenant within sixty (60) days following the casualty), to take
more than one hundred fifty (150) days from the date

                                       12
<PAGE>

of casualty to substantially complete, or (d) more than forty percent (40%) of
the Premises is affected by the damage, and fewer than twelve (12) months remain
in the Term. In order to exercise any of the foregoing termination rights,
Tenant must send Landlord notice specifying the basis for termination, and such
notice must be given no later than thirty (30) days following the occurrence of
the condition serving as the basis for the termination right invoked by Tenant,
except in the case of Tenant's termination right in (c) above, in which case
such notice must be given by Tenant within ten (10) business days after Tenant's
receipt of Landlord's estimate.

                                   ARTICLE 11
                  INSURANCE, SUBROGATION, AND WAIVER OF CLAIMS

         Tenant shall maintain during the Term Commercial General Liability
insurance, with limits of not less than $2,000,000 per occurrence for
personal injury, bodily injury or death, or property damage or destruction
(including loss of use thereof). Such insurance shall be primary and any
insurance carried by Landlord or any other insured shall be excess and
noncontributory. Tenant shall also maintain during the Term workers'
compensation insurance as required by statute, employer's liability insurance
in an amount of not less than $500,000 per occurrence, and primary,
noncontributory, "all-risk" property damage insurance covering Tenant's
personal property, business records, fixtures and equipment, for damage or
other loss caused by fire or other casualty or cause including, but not
limited to, vandalism and malicious mischief, theft, water damage of any
type, including sprinkler leakage, bursting or stoppage of pipes, explosion,
business interruption, and other insurable risks in amounts not less than the
full insurable replacement value of such property and full insurable value of
such other interests of Tenant (subject to reasonable deductible amounts).
Landlord shall, as part of Operating Expenses, maintain during the Term
Commercial General Liability insurance, with limits of not less than
$2,000,000 per occurrence for personal injury, bodily injury or death, or
property damage or destruction (including loss of use thereof). Landlord
shall also, as part of Operating Expenses, maintain during the Term workers'
compensation insurance as required by statute, and primary, non-contributory,
extended coverage or "all-risk" property damage insurance, in an amount equal
to one hundred percent (100%) of the full insurable replacement value of the
Property (exclusive of the costs of excavation, foundations and footings, and
such risks required to be covered by Tenant's insurance, and subject to
reasonable deductible amounts), or such other amount necessary to prevent
Landlord from being a co-insured, and such other coverage as Landlord shall
deem appropriate or that may be required by any Holder (as defined in
Article 25).

         Tenant shall provide Landlord with certificates evidencing such
coverage (and, with respect to liability coverage, showing Landlord and such
other parties that Landlord shall reasonably designate in a written notice to
Tenant from time to time as named insureds) prior to the Commencement Date,
which shall state that such insurance coverage may not be changed in any
material manner (provided that a change shall be deemed material if it
adversely affects Landlord or causes Tenant's insurance to fail to comply
with the terms of this Article 11) or canceled without at least thirty (30)
days prior written notice to Landlord,

                                       13
<PAGE>

and shall provide renewal certificates to Landlord at least thirty (30) days
prior to expiration of such policies. Except as provided to the contrary herein,
any insurance carried by Landlord or Tenant shall be for the sole benefit of the
party carrying such insurance. Any insurance policies hereunder may be "blanket
policies," provided that payments made in connection with other properties
covered by such blanket policies shall not diminish the insurance amounts
required hereunder. All insurance required hereunder shall be provided by
responsible insurers and Tenant's insurer shall have a rating of at least A-X in
the then current edition of Best's Key Rating Insurance guide and shall
otherwise be reasonably acceptable to Landlord. By this Article, Landlord and
Tenant intend that their respective property loss risks shall be borne by
responsible insurance carriers to the extent above provided, and Landlord and
Tenant hereby agree to look solely to, and seek recovery only from, their
respective insurance carriers in the event of a property loss to the extent that
such coverage is agreed to be provided hereunder. The parties each hereby waive
all rights and claims against such other for such losses, and waive all rights
of subrogation of their respective insurers, provided such waiver of subrogation
shall not affect the right of the insured to recover thereunder. The parties
agree that their respective insurance policies are now, or shall be, endorsed
such that said waiver of subrogation shall not affect the right of the insured
to recover thereunder, so long as no material additional premium is charged
therefor.

         Tenant shall carry and maintain during the entire Term, at Tenant's
sole cost and expense, increased amounts of the insurance required to be carried
by Tenant pursuant to this Article 11, and such other reasonable types of
insurance coverage and in such reasonable amounts covering the Premises and
Tenant's operations therein as may be reasonably requested by Landlord.

                                   ARTICLE 12
                                  CONDEMNATION

         If the whole or any material part of the Premises or Property shall be
taken by power of eminent domain or condemned by any competent authority for any
public or quasi-public use or purpose, or if any adjacent property or street
shall be so taken or condemned, or reconfigured or vacated by such authority in
such manner as to require the use, reconstruction or remodeling of any part of
the Premises or Property, or if Landlord shall grant a deed or other instrument
in lieu of such taking by eminent domain or condemnation, Landlord shall have
the option to terminate this Lease upon one hundred twenty (120) days notice,
provided such notice is given no later than one hundred eighty (180) days after
the date of such taking, condemnation, reconfiguration, vacation, deed or other
instrument. Tenant shall have reciprocal termination rights if the whole or any
material part of the Premises is permanently taken, or if access to the Premises
is permanently materially impaired. Landlord shall be entitled to receive the
entire award or payment in connection therewith, except that Tenant shall have
the right to file any separate claim available to Tenant for any taking of
Tenant's personal property and fixtures belonging to Tenant and removable by
Tenant upon expiration of the Term, and for moving expenses (so long as such
claim does not diminish the award available to

                                       14
<PAGE>

Landlord or any Holder, and such claim is payable separately to Tenant). All
Rent shall be apportioned as of the date of such termination, or the date of
such taking, whichever shall first occur. If any part of the Premises shall be
taken, and this Lease shall not be so terminated, the Rent shall be
proportionately abated.

                                   ARTICLE 13
                              RETURN OF POSSESSION

         At the expiration or earlier termination of this Lease or Tenant's
right of possession, Tenant shall surrender possession of the Premises in the
condition required under Article 9, ordinary wear and tear, loss or damage by
fire or other insured casualty, damage resulting from the wanton or negligent
acts of Landlord or its agents excepted, and shall surrender all keys, any key
cards, and any parking stickers or cards, to Landlord, and advise Landlord as to
the combination of any locks or vaults then remaining in the Premises, and shall
remove all trade fixtures and personal property. All improvements, fixtures and
other items in or upon the Premises (except trade fixtures and personal property
belonging to Tenant), whether installed by Tenant or Landlord, shall be
Landlord's property and shall remain upon the Premises, all without
compensation, allowance or credit to Tenant. However, if prior to such
termination or within ten (10) days thereafter Landlord so directs by notice,
Tenant shall promptly remove such of the foregoing items as are designated in
such notice and restore the Premises to the condition prior to the installation
of such items; provided, Landlord shall not require removal of customary office
improvements installed in compliance with the express provisions of this Lease,
the improvements installed pursuant to the Work Agreement or improvements
installed during the Term that are consistent with the improvements installed
pursuant to the Work Agreement, or improvements installed by Tenant with
Landlord's written approval (except as expressly required by Landlord in
connection with granting such approval). If Tenant shall fail to perform any
repairs or restoration, or fail to remove any items from the Premises required
hereunder, Landlord may do so, and Tenant shall pay Landlord the cost thereof
upon demand. All property removed from the Premises by Landlord pursuant to any
provisions of this Lease or any Law may be handled or stored by Landlord at
Tenant's expense, and Landlord shall in no event be responsible for the value,
preservation or safekeeping thereof. All property not removed from the Premises
or retaken from storage by Tenant within thirty (30) days after expiration or
earlier termination of this Lease or Tenant's right to possession, shall at
Landlord's option be conclusively deemed to have been conveyed by Tenant to
Landlord as if by bill of sale without payment by Landlord. Unless prohibited by
applicable Law, following the expiration or earlier termination of this Lease,
Landlord shall have a lien against such property for the costs incurred in
removing and storing the same.

                                       15

<PAGE>

                                   ARTICLE 14
                                  HOLDING OVER

         Unless Landlord expressly agrees otherwise in writing, Tenant shall pay
Landlord one hundred fifty percent (150%) of the amount of Rent then applicable
(or the highest amount permitted by Law, whichever shall be less) prorated on
per diem basis for each day Tenant shall retain possession of the Premises or
any part thereof after expiration or earlier termination of this Lease, together
with all actual damages sustained by Landlord on account thereof, including,
without limitation, any claims by any succeeding tenant founded on such delay.
The foregoing provisions shall not serve as permission for Tenant to hold-over,
nor serve to extend the Term (although Tenant shall remain bound to comply with
all provisions of this Lease until Tenant vacates the Premises, and shall be
subject to the provisions of Article 13). Notwithstanding the foregoing to the
contrary, at any time before or after expiration or earlier termination of the
Lease, Landlord may serve notice advising Tenant of the amount of Rent and other
terms required, should Tenant desire to enter a month-to-month tenancy (and if
Tenant shall hold over beyond the expiration or earlier termination of the Lease
more than one full calendar month after such notice, Tenant shall thereafter be
deemed a month-to-month tenant, on the terms and provisions of this Lease then
in effect, as modified by Landlord's notice, and except that Tenant shall not be
entitled to any renewal or expansion rights contained in this Lease or any
amendments hereto).

                                   ARTICLE 15
                                   NO WAIVER

         No provision of this Lease will be deemed waived by either party unless
expressly waived in writing signed by the waiving party. No waiver shall be
implied by delay or any other act or omission of either party. No waiver by
either party of any provision of this Lease shall be deemed a waiver of such
provision with respect to any subsequent matter relating to such provision, and
Landlord's consent or approval respecting any action by Tenant shall not
constitute a waiver of the requirement for obtaining Landlord's consent or
approval respecting any subsequent action. Acceptance of Rent by Landlord shall
not constitute a waiver of any breach by Tenant of any term or provision of this
Lease. No acceptance of a lesser amount than the Rent herein stipulated shall be
deemed a waiver of Landlord's right to receive the full amount due, nor shall
any endorsement or statement on any check or payment or any letter accompanying
such check or payment be deemed an accord and satisfaction, and Landlord may
accept such check or payment without prejudice to Landlord's right to recover
the full amount due. The acceptance of Rent or of the performance of any other
term or provision from any Person other than Tenant, including any Transferee,
shall not constitute a waiver of Landlord's right to approve any Transfer.


                                       16
<PAGE>

                                   ARTICLE 16
                         ATTORNEYS' FEES AND JURY TRIAL

         In the event of any litigation between the parties, the prevailing
party shall be entitled to obtain, as part of the judgment, all reasonable
attorneys' fees, costs and expenses incurred in connection with such litigation,
except as may be limited by applicable Law. In the interest of obtaining a
speedier and less costly hearing of any dispute, the parties hereby each
irrevocably waive the right to trial by jury.

                                   ARTICLE 17
              PERSONAL PROPERTY TAXES, RENT TAXES AND OTHER TAXES

         Tenant shall pay prior to delinquency all taxes, charges or other
governmental impositions assessed against or levied upon Tenant's fixtures,
furnishings, equipment and personal property located in the Premises, and any
Work to the Premises under Article 8. Whenever possible, Tenant shall cause all
such items to be assessed and billed separately from the property of Landlord.
In the event any such items shall be assessed and billed with the property of
Landlord, Tenant shall pay Landlord its share of such taxes (allocated on an
equitable basis), charges or other governmental impositions within thirty (30)
days after Landlord delivers a statement and a copy of the assessment or other
documentation, showing the amount of such impositions applicable to Tenant's
property. Tenant shall pay any separate rent tax or sales tax, service tax,
transfer tax or value added tax, or any other applicable tax on the Rent or
services herein or otherwise respecting this Lease.

                                   ARTICLE 18
                              REASONABLE APPROVALS

         Whenever Landlord's approval or consent is expressly required under
this Lease (including Article 21) or any other agreement between the parties,
Landlord shall not unreasonably withhold, condition or delay such approval or
consent, except as expressly provided herein to the contrary and except for
matters affecting the structure, safety or security of the Property, or the
appearance of the Property from any common or public areas.

                                   ARTICLE 19
               SUBORDINATION, ATTORNMENT AND MORTGAGEE PROTECTION

         This Lease is subject and subordinate to all Mortgages (as defined in
Article 25) now or hereafter placed upon the Property, and all other
encumbrances and matters of public record applicable to the Property. This
clause shall be self-operative and no further instrument of subordination shall
be required by any ground or underlying lessor or by any Holder (as defined in
Article 25), provided, that such ground or underlying lessor or Holder


                                       17
<PAGE>

shall accept this Lease and not disturb Tenant's occupancy, so long as Tenant
does not Default and fail to cure within the time permitted hereunder, and
provided further, that as a condition precedent to the effectiveness of this
Lease, Landlord shall obtain a subordination, non-disturbance and attornment
agreement from LaSalle Bank, N.A., in form and substance reasonably acceptable
to Tenant and LaSalle Bank, N.A. In connection with any Mortgage or ground lease
entered into after the Effective Date, Landlord shall endeavor to deliver, or
cause to be delivered to Tenant, and Tenant shall execute, a subordination,
non-disturbance and attornment agreement, which shall be on such mortgagee's or
ground lessor's form (and reasonably acceptable to Tenant). If any foreclosure
proceedings are initiated by any Holder or a deed in lieu is granted (or if any
ground lease is terminated), Tenant agrees, upon written request of any such
Holder or any purchaser at foreclosure sale, to attorn and pay Rent to such
party and to execute and deliver any instruments in commercially reasonable form
necessary or appropriate to evidence or effectuate such attornment (provided
such Holder or purchaser shall agree to accept this Lease and not disturb
Tenant's occupancy, so long as Tenant does not default and fail to cure within
the time permitted hereunder). However, in the event of attornment, no Holder
shall be: (i) liable for any act or omission of Landlord, or subject to any
offsets or defenses which Tenant might have against Landlord (prior to such
Holder becoming Landlord under such attornment), (ii) liable for any security
deposit or not actually received by such Holder or bound by any Rent prepaid
more than one (1) month in advance, or (iii) bound by any modification of this
Lease entered into after the date of such Holder's Mortgage that is not
consented to by such Holder (provided that Tenant has received notice from
Landlord of the name and address of such Holder). Any Holder (as defined in
Article 25) may elect to make this Lease prior to the lien of its Mortgage, by
written notice to Tenant, and if the Holder of any prior Mortgage shall require,
this Lease shall be prior to any subordinate Mortgage. Tenant agrees to give any
Holder by certified mail, return receipt requested, a copy of any notice of
default served by Tenant upon Landlord, provided that prior to such notice
Tenant has been notified in writing (by way of service on Tenant of a copy of an
assignment of leases, or otherwise) of the name and address of such Holder.
Tenant further agrees that if Landlord shall have failed to cure such default
within the times permitted Landlord for cure under this Lease, any such Holder
whose address has been provided to Tenant and who has received a notice of
default from Tenant shall have an additional period of thirty (30) days in which
to cure (or such additional time as may be required due to causes beyond such
Holder's control, including time to obtain possession of the Property by power
of sale or judicial action). Tenant shall execute such documentation as Landlord
may reasonably request from time to time, in order to confirm the matters set
forth in this Article in recordable form.

                                   ARTICLE 20
                              ESTOPPEL CERTIFICATE

         Tenant shall from time to time, within twenty (20) days after written
request from Landlord or any Holder, execute, acknowledge and deliver to
Landlord or any Holder a statement (i) certifying that this Lease is unmodified
and in full force and effect or, if modified, stating the nature of such
modification and certifying that this Lease as so


                                       18
<PAGE>

modified, is in full force and effect (or if this Lease is claimed not to be in
force and effect, specifying the ground therefor) and any dates to which the
Rent has been paid in advance, and the amount of any Security Deposit, (ii)
acknowledging that, to Tenant's knowledge, there are not any uncured defaults on
the part of Landlord or Tenant hereunder, or specifying such defaults if any are
claimed, (iii) stating whether Tenant has any rights to offsets or abatement of
Rent, and (iv) certifying such other matters pertaining to this Lease as
Landlord may reasonably request, or as may be requested by Landlord's current or
prospective Holders, insurance carriers, auditors, and prospective purchasers.
Any such statement may be relied upon by any such parties. If Tenant shall fail
to execute and return such statement with such modifications that Tenant deems
reasonably necessary to make the certificate accurate within the time required
herein, Tenant shall be deemed to have agreed with the matters set forth
therein.

                                   ARTICLE 21
                           ASSIGNMENT AND SUBLETTING

         (A) TRANSFERS. Tenant shall not, without the prior written consent
of Landlord, which consent shall not be unreasonably withheld, conditioned or
delayed, as further described below: (i) assign, mortgage, pledge,
hypothecate, encumber, or permit any lien to attach to, or otherwise
transfer, this Lease or any interest hereunder, by operation of law or
otherwise, (ii) sublet the Premises or any part thereof, or (iii) permit the
use of the Premises by any Persons (as defined in Article 25) other than
Tenant and its employees (all of the foregoing are hereinafter sometimes
referred to collectively as "TRANSFERS" and any Person to whom any Transfer
is made or sought to be made is hereinafter sometimes referred to as a
"TRANSFEREE"). If Tenant shall desire Landlord's consent to any Transfer,
Tenant shall notify Landlord in writing, which notice shall include: (a) the
proposed effective date (which shall not be less than thirty (30) nor more
than one hundred eighty (180) days after Tenant's notice), (b) the portion of
the Premises to be Transferred (herein called the "SUBJECT SPACE"), (c) the
terms of the proposed Transfer and the consideration therefor, the name and
address of the proposed Transferee, and a copy of all documentation
pertaining to the proposed Transfer, and (d) current financial statements of
the proposed Transferee certified by an officer, partner or owner thereof,
and any other information that Landlord may reasonably require to enable
Landlord to determine the financial responsibility, character, and reputation
of the proposed Transferee, nature of such Transferee's business and proposed
use of the Subject Space, and such other information as Landlord may
reasonably require. Any Transfer made without complying with this Article
shall, at Landlord's option, be null, void and of no effect, or shall
constitute a Default under this Lease. Whether or not Landlord shall grant
consent, Tenant shall pay the reasonable out-of-pocket costs and expenses
incurred by Landlord in reviewing and processing Tenant's request for
consent, within thirty (30) days after presentation by Landlord of its
statement setting forth such costs and expenses.

         (B) APPROVAL. Landlord will not unreasonably withhold, condition or
delay its consent (as provided in Article 18) to any proposed Transfer of the
Subject Space to the Transferee on the terms specified in Tenant's notice. The
parties hereby agree that it shall


                                       19
<PAGE>

be reasonable under this Lease and under any applicable Law for Landlord to
withhold consent to any proposed Transfer where one or more of the following
applies (without limitation as to other reasonable grounds for withholding
consent): (i) the Transferee is of a character or reputation or engaged in a
business which is not consistent with the quality of the Property, (ii) the
Transferee intends to use the Subject Space for purposes which are not permitted
under this Lease, (iii) the Subject Space is not regular in shape with
appropriate means of ingress and egress suitable for normal renting purposes,
(iv) the Transferee is either a government (or agency or instrumentality
thereof), foreign embassy or other foreign entity or person having diplomatic
immunity, or an occupant of the Property (provided, however, that if there is no
vacant space comparable in size to the Subject Space available for occupancy at
the Property, then a Transfer to an occupant of the Property may occur), (v) the
proposed Transferee does not have a reasonable financial condition in relation
to the obligations to be assumed in connection with the Transfer, or (vi) Tenant
has committed and failed to cure a Default at the time Tenant requests consent
to the proposed Transfer.

         (C) TRANSFER PREMIUM. If Landlord consents to a Transfer, and as a
condition thereto which the parties hereby agree is reasonable, Tenant shall pay
Landlord fifty percent (50%) of any Transfer Premium derived by Tenant from such
Transfer. "TRANSFER PREMIUM" shall mean all rent, additional Rent or other
consideration paid by such Transferee in excess of the Rent payable by Tenant
under this Lease (on a monthly basis during the Term, and on a per rentable
square foot basis, if less than all of the Premises is transferred), after
deducting the reasonable expenses incurred by Tenant for any changes,
alterations and improvements to the Premises, any other economic concessions or
services provided to the Transferee, and any customary brokerage commissions and
legal fees paid in connection with the Transfer. If part of the consideration
for such Transfer shall be payable other than in cash, Landlord's share of such
non-cash consideration shall be in such form as is reasonably satisfactory to
Landlord. The percentage of the Transfer Premium due Landlord hereunder shall be
paid by Tenant with each installment of Rent due immediately following Tenant's
receipt of any Transfer Premium from the Transferee.

         (D) RECAPTURE. Notwithstanding anything to the contrary contained in
this Article, Landlord shall have the option, by giving written notice to
Tenant within fifteen (15) days after receipt of Tenant's notice of any
proposed Transfer, to recapture the Subject Space, if (i) the proposed
Transfer if an assignment of the Lease or a sublease of the entire Premises
for the balance of the Term, (ii) the term of the proposed Transfer,
including all renewal terms, exceeds fifty percent (50%) of the balance of
the Term, or (iii) the Subject Space, either by itself or when added to any
other portion of the Premises at the time of Tenant's notice of Transfer than
subject to a sublease, exceeds fifty percent (50%) of the rentable square
feet of the Premises. Such recapture notice shall cancel and terminate this
Lease with respect to the Subject Space as of the date stated in Tenant's
notice as the effective date of the proposed Transfer (or at Landlord's
option, shall cause the Transfer to be made to Landlord or its agent, in
which case the parties shall execute the Transfer documentation promptly
thereafter), unless Tenant elects (and notifies Landlord in writing of such
election) (the "OPTION TO VOID A RECAPTURE"), within five (5) business days
after Landlord notifies Tenant that it intends to recapture the Subject Space,

                                       20
<PAGE>

to void the notice of the Proposed Transfer, whereupon (i) Landlord shall not
recapture the Subject Space, (ii) the proposed Transfer shall not occur, and
(iii) the Lease shall continue in full force with respect to the Subject Space,
with Tenant in occupancy thereof. If this Lease shall be cancelled with respect
to less than the entire Premises, the Rent reserved herein shall be prorated on
the basis of the number of rentable square feet retained by Tenant in proportion
to the number of rentable square feet contained in the Premises and Tenant's
Prorata Share of Taxes and Operating Expenses shall be equitably adjusted based
on the rentable square feet retained by Tenant, this Lease as so amended shall
continue thereafter in full force and effect, and upon request of either party,
the parties shall execute written confirmation of the same.

         (E) TERMS OF CONSENT. If Landlord consents to a Transfer: (a) the
terms and conditions of this Lease shall in no way be deemed to have been
waived or modified, (b) such consent shall not be deemed consent to any
further Transfer by either Tenant or a Transferee, (c) no Transferee, other
than a Related Entity, shall succeed to any rights provided in this Lease or
any amendment hereto to extend the Term of this Lease, expand the Premises,
or lease additional space, any such rights being deemed personal to Tenant,
(d) no Transfer relating to this Lease or agreement entered into with respect
thereto, whether with or without Landlord's consent, shall relieve Tenant or
any guarantor of this Lease from liability under this Lease, (e) Tenant shall
deliver to Landlord promptly after execution, an original executed copy of
all documentation pertaining to the Transfer in form reasonably acceptable to
Landlord, and (f) Tenant shall furnish upon Landlord's request a complete
statement, certified by an independent certified public accountant, or
Tenant's chief financial officer, setting forth in detail the computation of
any Transfer Premium Tenant has derived and shall derive from such Transfer.
Landlord or its authorized representatives shall have the right at all
reasonable times to audit the books, records and papers of Tenant relating to
any Transfer Premium, and shall have the right, at Landlord's expense, to
make copies thereof. If the Transfer Premium respecting any Transfer shall be
found understated, Tenant shall within thirty (30) days after demand pay the
deficiency, and if understated by more than three percent (3%), Tenant shall
pay Landlord's actual, out-of-pocket costs of such audit. Any sublease
hereunder shall be subordinate and subject to the provisions of this Lease,
and if this Lease shall be terminated during the term of any sublease,
Landlord shall have the right to: (i) treat such sublease as canceled and
repossess the Subject Space by any lawful means, or (ii) require that such
subtenant attorn to and recognize Landlord as its landlord under any such
sublease. If Tenant shall Default and fail to cure within the time permitted
for cure under Article 23(A), Landlord is hereby irrevocably authorized, as
Tenant's agent and attorney-in-fact, to direct any Transferee to make all
payments under or in connection with the Transfer directly to Landlord (which
Landlord shall apply towards Tenant's obligations under this Lease) until
such Default is cured.

         (F) CERTAIN TRANSFERS. For purposes of this Lease, the term "TRANSFER"
shall also include (a) if Tenant is a partnership, the withdrawal or change,
voluntary, involuntary or by operation of law, of a majority of the partners, or
a transfer of a majority of partnership interests, within a twelve (12) month
period, or the dissolution of the partnership, and (b) if Tenant is a
corporation, the dissolution, merger, consolidation or


                                       21
<PAGE>

other reorganization of Tenant, or within a twelve (12) month period: (i) the
sale or other transfer of more than an aggregate of fifty percent (50%) of the
voting shares of Tenant (other than to immediate family members by reason of
gift or death) or (ii) the sale, mortgage, hypothecation or pledge of more than
an aggregate of fifty percent (50%) of Tenant's net assets. For purposes of this
Lease, the term "TRANSFER" shall not include the transfer or sale of any of
Tenant's stock, or the stock of any affiliate of Tenant, on a nationally
recognized stock exchange.

         (G) RELATED ENTITIES. Notwithstanding anything to the contrary in this
Article 21, Tenant may, without Landlord's consent, permit any corporation or
other business entity which controls or is controlled by, or is under common
control with Tenant (a "RELATED ENTITY") to sublet all or part of the Premises
or receive an assignment of the Lease, provided that (i) Tenant shall not be in
Default under this Lease, (ii) prior to or promptly after (but in no event more
than thirty (30) days) such subletting or assignment, as the case may be, Tenant
gives Landlord written notice of such sublease or assignment and furnishes
Landlord with the name of any such Related Entity, together with a certification
of Tenant, and such other proof as Landlord may reasonably request, that such
subtenant or assignee, as the case may be, is a Related Entity of Tenant.
Landlord shall have the right, at any reasonable time, to examine such books and
records of Tenant as may be necessary to establish that such sublessee or
assignee, as the case may be, is a Related Entity of Tenant. Such subletting or
assignment shall not relieve Tenant of any of Tenant's liability or obligations
under this Lease. For the purposes hereof "CONTROL" shall mean the power to
directly or indirectly direct or cause the direction of the management or
policies of such corporation or entity.

                                   ARTICLE 22
                          RIGHTS RESERVED BY LANDLORD

         Except to the extent expressly limited herein, Landlord reserves full
rights to control the Property (which rights may be exercised without subjecting
Landlord to claims for constructive eviction, abatement of Rent, damages or
other claims of any kind), including more particularly, but without limitation,
the following rights:

         (A) To change the name or street address of the Property upon
reasonable prior notice to Tenant; install and maintain signs on the exterior
and interior of the Property; retain at all times, and use in appropriate
instances, keys to all doors within and into the Premises; grant to any person
the right to conduct any business or render any service at the Property, whether
or not it is the same or similar to the use permitted Tenant by this Lease; and
have access for Landlord and other tenants of the Property to any mail chutes
located on the Premises according to the rules of the United States Postal
Service.

         (B) To enter the Premises at reasonable hours for reasonable purposes
and upon reasonable prior notice (which may be verbal), including inspection and
supplying cleaning service or other services (for which no notice shall be
required) to be provided Tenant hereunder, to show the Premises to current and
prospective mortgage lenders,


                                       22
<PAGE>

ground lessors, insurers, and prospective purchasers, tenants and brokers, at
reasonable hours upon reasonable prior notice, and if Tenant shall abandon the
Premises for a period of one hundred eighty (180) days, at any time, or shall
vacate the same during the last three (3) months of the Term, to decorate,
remodel, repair, or alter the Premises.

         (C) To limit or prevent access to the Property, shut down elevator
service, activate elevator emergency controls, or otherwise take such action or
preventative measures reasonably deemed necessary by Landlord for the safety of
tenants or other occupants of the Property or the protection of the Property and
other property located thereon or therein, in case of fire, invasion,
insurrection, riot, civil disorder, public excitement or other dangerous
condition, or threat thereof.

         (D) To decorate and to make alterations, additions and improvements,
structural or otherwise, in or to the Property or any part thereof, and any
adjacent building, structure, parking facility, land, street or alley (including
without limitation changes and reductions in corridors, lobbies, parking
facilities and other public areas and the installation of kiosks, planters,
sculptures, displays, escalators, mezzanines, and other structures, facilities,
amenities and features therein, and changes for the purpose of connection with
or entrance into or use of the Property in conjunction with any adjoining or
adjacent building or buildings, now existing or hereafter constructed), so long
as Tenant maintains reasonable access to the Premises. In connection with such
matters, or with any other repairs, maintenance, improvements, or alterations,
in or about the Property, Landlord may erect scaffolding and other structures
reasonably required, and during such operations may enter upon the Premises and
take into and upon or through the Premises, all materials required to make such
repairs, maintenance, alterations or improvements, and may close public entry
ways, other public areas, restrooms, stairways or corridors.

         (E) Intentionally Deleted.

         In connection with entering the Premises to exercise any of the
foregoing rights, Landlord shall: (a) provide reasonable advance written or oral
notice to Tenant's on-site manager or other appropriate person (except in
emergencies, or for routine cleaning or other routine matters), (b) take
reasonable steps to minimize any interference with Tenant's business, (c)
Landlord shall diligently complete any work for which it is entering the
Premises, and (d) Landlord shall properly store all equipment and materials at
the end of each workday.

                                   ARTICLE 23
                              LANDLORD'S REMEDIES

         (A) DEFAULT. The occurrence of any one or more of the following events
shall constitute a "DEFAULT" by Tenant, which if not cured within any applicable
time permitted for cure below, shall give rise to Landlord's remedies set forth
in Paragraph (B), below: (i) failure by Tenant to make when due any payment of
Rent, unless such failure is cured within ten (10) days after written notice to
Tenant; (ii) failure by Tenant to observe or


                                       23
<PAGE>

perform any of the terms or conditions of this Lease to be observed or
performed by Tenant other than the payment of Rent, or as provided below,
unless such failure is cured within thirty (30) days after written notice to
Tenant setting forth in reasonable detail the nature and extent of the
failure, or such shorter period expressly provided elsewhere in this Lease
(provided, if the nature of Tenant's failure is such that more time is
reasonably required in order to cure, Tenant shall not be in Default if
Tenant commences to cure within such period and thereafter reasonably seeks
to cure such failure to completion); (iii) failure by Tenant to comply with
the Rules, unless such failure is cured within five (5) business days after
notice (provided, if the nature of Tenant's failure is such that more time is
reasonably required in order to cure, Tenant shall not be in Default if
Tenant commences to cure within such period and thereafter reasonably seeks
to cure such failure to completion); (iv) vacation of all of the Premises for
more than one hundred eighty (180) consecutive days, or, if the Premises
consist of three (3) full floors or more, vacation of at least two (2) full
floors of the Premises for more than one hundred eighty (180) days, but in
either case, only if Tenant has failed to pay Rent when due, or the failure
of Tenant to occupy the Premises within one hundred eighty (180) days after
the Commencement Date; (v) (a) making by Tenant or any guarantor of this
Lease ("GUARANTOR") of any general assignment for the benefit of creditors,
(b) filing by or against Tenant or any Guarantor of a petition to have Tenant
or such Guarantor adjudged a bankrupt or a petition for reorganization or
arrangement under any Law relating to bankruptcy (unless, in the case of a
petition filed against Tenant or such Guarantor, the same is dismissed within
sixty (60) days, (c) appointment of a trustee or receiver to take possession
of substantially all of Tenant's assets located on the Premises or of
Tenant's interest in this Lease, where possession is not restored to Tenant
within sixty (60) days, (d) attachment, execution or other judicial seizure
of substantially all of Tenant's assets located on the Premises or of
Tenant's interest in this Lease, (e) Tenant's or any Guarantor's convening of
a meeting of its creditors or any class thereof for the purpose of effecting
a moratorium upon or composition of its debts, or (f) Tenant's or any
Guarantor's insolvency or admission of an inability to pay its debts as they
mature; (vi) any material misrepresentation herein, or material
misrepresentation or omission in any financial statements or other materials
provided by Tenant or any Guarantor in connection with negotiating or
entering this Lease or any material misrepresentation or omission by Tenant
in connection with any Transfer under Article 21; and (vii) cancellation of
any guaranty of this Lease by any Guarantor. Failure by Tenant to comply with
the provisions of this Lease regarding payment of Rent or to comply with same
material, non-monetary term or condition of this Lease on three occasions
during any twelve (12) month period shall cause any failure to comply with
such term or condition during the succeeding twelve (12) month period, at
Landlord's option, to constitute an incurable Default, if Landlord has given
Tenant notice of each such failure within ten (10) days after each such
failure occurs. The notice and cure periods provided herein are in lieu of,
and not in addition to, any notice and cure periods provided by Law.

         (B) REMEDIES. If a Default occurs and is not cured within any
applicable time permitted under Paragraph (A), Landlord shall have the rights
and remedies hereinafter set forth, which shall be distinct, separate and
cumulative with and in addition to any other right or remedy allowed under any
Law or, other provisions of this Lease:


                                       24
<PAGE>

                  (i)      Landlord may terminate this Lease, repossess the
                           Premises by detainer suit, summary proceedings or
                           other lawful means, and recover as damages a sum of
                           money equal to: (a) any unpaid Rent as of the
                           termination date including interest at the Default
                           Rate (as defined in Article 25), (b) any unpaid Rent
                           which would have accrued after the termination date
                           through the time of award including interest at the
                           Default Rate, less such loss of Rent that Tenant
                           proves could have been reasonably avoided, (c) any
                           unpaid Rent which would have accrued after the time
                           of award during the balance of the Term, less such
                           loss of Rent that Tenant proves could be reasonably
                           avoided, discounted to present value at an interest
                           rate equal to the average yield on United States
                           Treasury securities having a maturity date closest to
                           the Expiration Date, and (d) any other amounts
                           necessary to compensate Landlord for all damages
                           proximately caused by Tenant's failure to perform its
                           obligations under this Lease, including without
                           limitation all Costs of Reletting (as defined in
                           Paragraph F). For purposes of computing the amount of
                           Rent herein that would have accrued after the time of
                           award, Tenant's Prorata Share of Taxes and Operating
                           Expenses shall be projected, based upon the average
                           rate of increase, if any, in such items from the
                           Commencement Date through the time of award.

                  (ii)     If applicable Law permits, Landlord may terminate
                           Tenant's right of possession and repossess the
                           Premises by detainer suit, summary proceedings or
                           other lawful means, without terminating this Lease
                           (and if such Law permits, and Landlord shall not have
                           expressly terminated the Lease in writing, any
                           termination shall be deemed a termination of Tenant's
                           right of possession only). In such event, Landlord
                           may recover: (a) any unpaid Rent as of the date
                           possession is terminated, including interest at the
                           Default Rate, (b) any unpaid Rent which accrues
                           during the Term from the date possession is
                           terminated through the time of award (or which may
                           have accrued from the time of any earlier award
                           obtained by Landlord through the time of award),
                           including interest at the Default Rate, less any Net
                           Re-Letting Proceeds (as defined in Paragraph F)
                           received by Landlord during such period, and less
                           such loss of Rent that Tenant proves could have been
                           reasonably avoided, and (c) any other amounts
                           necessary to compensate Landlord for all damages
                           proximately caused by Tenant's failure to perform
                           its obligations under this Lease, including without
                           limitation, all Costs of Reletting (as defined in
                           Paragraph F). Landlord may bring suits for such
                           amounts or portions thereof, at any time or times as
                           the same accrue or after the same have accrued, and
                           no suit or recovery of any portion due hereunder
                           shall be deemed a waiver of Landlord's right to
                           collect all amounts to which Landlord is entitled
                           hereunder, nor shall


                                       25
<PAGE>

                           the same serve as any defense to any subsequent suit
                           brought for any amount not theretofore reduced to
                           judgment.

         (C) MITIGATION OF DAMAGES. If Landlord terminates this Lease or
Tenant's right to possession, Landlord shall use reasonable efforts to mitigate
Landlord's damages, and Tenant shall be entitled to submit proof of such failure
to mitigate as a defense to Landlord's claims hereunder if mitigation of damages
by Landlord is required by applicable law. If Landlord has not terminated this
Lease or Tenant's right to possession, Landlord shall have no obligation to
mitigate and may permit the Premises to remain vacant or abandoned; in such
case, Tenant may seek to mitigate damages by attempting to sublease the
Premises or assign this Lease (subject to Article 21).

         (D) SPECIFIC PERFORMANCE, COLLECTION OF RENT AND ACCELERATION. Landlord
shall at all times have the rights and remedies (which shall be cumulative with
each other and cumulative and in addition to those rights and remedies available
under Paragraph (B), above or any Law or other provision of this Lease), without
prior demand or notice except as required by applicable Law: (i) to seek any
declaratory, injunctive or other equitable relief, and specifically enforce this
Lease, or restrain or enjoin a violation or breach of any provision hereof, and
(ii) to sue for and collect any unpaid Rent which has accrued. Notwithstanding
anything to the contrary contained in this Lease, to the extent not expressly
prohibited by applicable Law, in the event of any Default by Tenant not cured
within any applicable time for cure hereunder, Landlord may terminate this Lease
or Tenant's right to possession and accelerate and declare that all Rent
reserved for the remainder of the Term shall be immediately due and payable (in
which event, Tenant's Prorata Share of Taxes and Operating Expenses for the
remainder of the Term shall be projected based upon the average rate of
increase, if any, in such items from the Commencement Date through the date of
such declaration), and such amount shall be discounted to present value at an
interest rate equal to the average yield on United States Treasury securities
having a maturity date closest to the Expiration Date; provided, Landlord shall,
after receiving payment of the same from Tenant, be obligated to turn over to
Tenant any actual Net Re-Letting Proceeds thereafter received during the
remainder of the Term, up to the amount so received from Tenant pursuant to this
provision.

         (E) LATE CHARGES AND INTEREST. On the second occasion and each
subsequent occasion during a Lease Year that Tenant fails to pay any Rent within
five (5) business days of its due date, Tenant shall pay, as additional Rent, a
service charge of Two Hundred Dollars ($200.00) for bookkeeping and
administrative expenses, if Rent is not received within five (5) business days
after its due date. In addition, Rent paid more than five (5) business days
ater due shall accrue interest from the due date at the Default Rate (as
defined in Article 25), until payment is received by Landlord. Such service
charge and interest payments shall not be deemed consent by Landlord to late
payments, nor a waiver of Landlord's right to insist upon timely payments at
any time, nor a waiver of any remedies to which Landlord is entitled as a
result of the late payment of Rent.

         (F) CERTAIN DEFINITIONS. "NET RE-LETTING PROCEEDS" shall mean the total
amount of rent and other consideration paid by any Replacement Tenants, less all
Costs


                                       26
<PAGE>


of Re-Letting, during a given period of time. "COSTS OF RE-LETTING" shall
include without limitation, all reasonable costs and expenses incurred by
Landlord for any repairs, maintenance, changes, alterations and improvements to
the Premises, brokerage commissions, advertising costs, attorneys' fees, any
customary free rent periods or credits, tenant improvement allowances, take-over
lease obligations and other customary, necessary or appropriate economic
incentives required to enter leases with Replacement Tenants, and costs of
collecting rent from Replacement Tenants. "REPLACEMENT TENANTS" shall mean any
Persons (as defined in Article 25) to whom Landlord relets the Premises or any
portion thereof pursuant to this Article.

         (G) OTHER MATTERS. No re-entry or repossession, repairs, changes,
alterations and additions, reletting, acceptance of keys from Tenant, or any
other action or omission by Landlord shall be construed as an election by
Landlord to terminate this Lease or Tenant's right to possession, or accept a
surrender of the Premises, nor shall the same operate to release the Tenant in
whole or in part from any of Tenant's obligations hereunder, unless express
written notice of such intention is sent by Landlord or its agent to Tenant. To
the fullest extent permitted by Law, all rent and other consideration paid by
any Replacement Tenants shall be applied: first, to the Costs of Re-Letting,
second, to the payment of any Rent theretofore accrued, and the residue, if any,
shall be held by Landlord and applied to the payment of other obligations of
Tenant to Landlord as the same become due (with any remaining residue to be
retained by Landlord). Rent shall be paid without any prior demand or notice
therefor (except as expressly provided herein) and without any deduction,
set-off or counterclaim, or relief from any valuation or appraisement laws,
except as otherwise expressly provided for in this Lease. Landlord may apply
payments received from Tenant to any obligations of Tenant then accrued, without
regard to such obligations as may be designated by Tenant. Landlord shall be
under no obligation to observe or perform any provision of this Lease on its
part to be observed or performed which accrues after the date of any Default by
Tenant hereunder not cured within the times permitted hereunder. The times set
forth herein for the curing of Defaults by Tenant are of the essence of this
Lease. Tenant hereby irrevocably waives any right otherwise available under any
Law to redeem or reinstate this Lease.

                                   ARTICLE 24
                            LANDLORD'S RIGHT TO CURE

         Except as expressly provided to the contrary in any provision of this
Lease, if Landlord shall fail to perform any term or provision under this
Lease required to be performed by Landlord, Landlord shall not be deemed to be
in default hereunder nor subject to any claims for damages of any kind, unless
such failure shall have continued for a period of thirty (30) days after written
notice thereof by Tenant; provided, if the nature of Landlord's failure is such
that more than thirty (30) days are reasonably required in order to cure,
Landlord shall not be in default if Landlord commences to cure such failure
within such thirty (30) day period, and thereafter reasonably seeks to cure such
failure to completion. The aforementioned periods of time permitted for Landlord
to cure shall be extended for any period of time during which Landlord is
delayed in, or prevented from,


                                       27
<PAGE>

curing due to fire or other casualty, strikes, lock-outs or other labor
troubles, shortages of equipment or materials, governmental requirements, power
shortages or outages, acts or omissions by Tenant or other Persons, and other
causes beyond Landlord's reasonable control.

         If Landlord shall fail to cure within the times permitted for cure
herein, Landlord shall be subject to such remedies as may be available to
Tenant, including, without limitation, all of the rights and remedies Tenant may
have at law or in equity (subject to the other provisions of this Lease);
provided, however, in recognition that Landlord must receive timely payments of
Rent and operate the Property, Tenant shall have no right of self-help to
perform repairs or any other obligation of Landlord, and shall have no right to
withhold, set-off or abate Rent.

                                   ARTICLE 25
                     CAPTIONS, DEFINITIONS AND SEVERABILITY

         The captions of the Articles and Paragraphs of this Lease are for
convenience of reference only and shall not be considered or referred to in
resolving questions of interpretation. If any term or provision of this Lease
shall be found invalid, void, illegal, or unenforceable with respect to any
particular Person by a court of competent jurisdiction, it shall not affect,
impair or invalidate any other terms or provisions hereof, or its enforceability
with respect to any other Person, the parties hereto agreeing that they would
have entered into the remaining portion of this Lease notwithstanding the
omission of the portion or portions adjudged invalid, void, illegal, or
unenforceable with respect to such Person.

         (A) "BUILDING" shall mean the structure identified in Article 1 of this
Lease.

         (B) "DEFAULT RATE" shall mean the prime rate of interest, as announced
by THE WALL STREET JOURNAL from time to time, plus five percent (5%) per annum,
or the highest rate permitted by applicable Law, whichever shall be less.

         (C) "HOLDER" shall mean the holder of any Mortgage at the time in
question, and where such Mortgage is a ground lease, such term shall refer to
the ground lessor.

         (D) "HOLIDAYS" shall mean all federally observed holidays, including
New Year's Day, President's Day, Memorial Day, Independence Day, Labor Day,
Veterans' Day, Thanksgiving Day, Christmas Day.

         (E) "LANDLORD" and "TENANT" shall be applicable to one or more Persons
as the case may be, and the singular shall include the plural, and the neuter
shall include the masculine and feminine; and if there be more than one, the
obligations thereof shall be joint and several. For purposes any provisions
indemnifying or limiting the liability of Landlord, the term "Landlord" shall
include Landlord's present and future partners,


                                       28
<PAGE>

beneficiaries, trustees, officers, directors, employees, shareholders,
principals, agents, affiliates, successors and assigns.

         (F) "LAW" shall mean all federal, state, county and local governmental
and municipal laws, statutes, ordinances, rules, regulations, codes, decrees,
orders and other such requirements, applicable equitable remedies and decisions
by courts in cases where such decisions are considered binding precedents in the
state in which the Property is located, and decisions of federal courts applying
the Laws of such State.

         (G) "LEASE YEAR" shall mean each twelve (12) month period during the
Term, commencing on the Commencement Date, without regard to calendar years;
provided, however, if the Commencement Date occurs on a day other than the first
day of a calendar month, the first Lease Year shall also include the period from
the Commencement Date to the last day of the calendar month in which the
Commencement Date occurs.

         (H) "MORTGAGE" shall mean all mortgages, deeds of trust, ground leases
and other such encumbrances now or hereafter placed upon the Property or
Building, or any part thereof, and all renewals, modifications, consolidations,
replacements, increases, spreaders or extensions thereof, and all indebtedness
now or hereafter secured thereby and all interest thereon.

         (I) "OPERATING EXPENSES" shall mean all expenses, costs and amounts
(other than Taxes) of every kind and nature which Landlord shall pay during any
calendar year any portion of which occurs during the Term, because of or in
connection with the ownership, management, repair, maintenance, restoration and
operation of the Property, including without limitation, any amounts paid for:
(a) utilities for the Property, including but not limited to electricity, power,
gas, steam, oil or other fuel, water, sewer, lighting, heating, air conditioning
and ventilating, (b) permits, licenses and certificates necessary to operate,
manage and lease the Property, (c) insurance applicable to the Property, not
limited to the amount of coverage Landlord is required to provide under this
Lease, (d) supplies, tools, equipment and materials used in the operation,
repair and maintenance of the Property, (e) accounting, legal, inspection,
consulting, concierge and other services, (f) any equipment rental (or
installment equipment purchase or equipment financing agreements), or management
agreements (including the cost of any management fee actually paid thereunder
and the fair rental value of any office space provided thereunder, up to
customary and reasonable amounts), (g) wages, salaries and other compensation
and benefits (including the fair value of any parking privileges provided) for
all persons engaged in the operation, maintenance or security of the Property,
and employer's Social Security taxes, unemployment taxes or insurance, and any
other taxes which may be levied on such wages, salaries, compensation and
benefits, and (h) operation, repair, and maintenance of all Systems and
Equipment and components thereof (including replacement of components),
janitorial service, alarm and security service, window cleaning, trash removal,
elevator maintenance, cleaning of walks, parking facilities and building walls,
removal of ice and snow, replacement of wall and floor coverings, ceiling tiles
and fixtures in lobbies, corridors, restrooms and other common or public areas
or


                                       29
<PAGE>

facilities, maintenance and replacement of shrubs, trees, grass, sod and other
landscaped items, irrigation systems, drainage facilities, fences, curbs, and
walkways, re-paving and re-striping parking facilities, and roof repairs. If the
Property is not fully occupied during all or a portion of any calendar year,
Landlord may, in accordance with sound accounting and management practices,
determine the amount of variable Operating Expenses (i.e., those items which
vary according to occupancy levels) that would have been paid had the Property
been fully occupied, and the amount so determined shall be deemed to have been
the amount of variable Operating Expenses for such year (such determination is
referred to herein as "GROSSING UP" variable Operating Expenses. If Landlord
grosses up such variable Operating Expenses during a calendar year, Landlord
shall also gross up the amount of variable Operating Expenses for the Base
Expense Year for purposes of determining Tenant's Prorata Share of Operating
Expenses due and payable with respect to such calendar year.

         Notwithstanding the foregoing, Operating Expenses shall not, however,
include:

                  (i)      depreciation, interest and amortization on Mortgages,
                           and other debt costs or ground lease payments, if
                           any; legal fees in connection with leasing, tenant
                           disputes or enforcement of leases; real estate
                           brokers' leasing commissions; improvements or
                           alterations to tenant spaces; the cost of providing
                           any service directly to and paid directly by, any
                           tenant; any costs expressly excluded from Operating
                           Expenses elsewhere in this Lease; costs of any items
                           to the extent Landlord receives reimbursement from
                           insurance proceeds or from a third party (such
                           proceeds to be deducted from Operating Expenses in
                           the year in which received);

                  (ii)     capital expenditures, except those: (a) made
                           primarily to reduce Operating Expenses, or to comply
                           with any Laws or other governmental requirements, or
                           (b) for replacements (as opposed to additions or new
                           improvements) of non-structural items located in the
                           common areas of the Property required to keep such
                           areas in good condition; provided, all such permitted
                           capital expenditures (together with reasonable
                           financing charges) shall be amortized for purposes of
                           this Lease over the shorter of: (i) their useful
                           lives, or (ii) the period during which the reasonably
                           estimated savings in Operating Expenses equals the
                           expenditures; and

                  (iii)    The items listed on EXHIBIT B attached hereto.

         (J) "PERSON" shall mean an individual, trust, partnership, joint
venture, association, corporation, and any other entity.

         (K) "PROPERTY" shall mean the Building, and any common or public areas
or facilities, easements, corridors, lobbies, sidewalks, loading areas,
driveways, landscaped


                                       30
<PAGE>

areas, skywalks, parking garages and lots, and any and all other structures or
facilities operated or maintained in connection with or for the benefit of the
Building, and all parcels or tracts of land on which all or any portion of the
Building or any of the other foregoing items are located, and any fixtures,
machinery, equipment, apparatus, Systems and Equipment, furniture and other
personal property located thereon or therein and used in connection therewith,
whether title is held by Landlord or its affiliates. Possession of areas
necessary for utilities, services, safety and operation of the Property,
including the Systems and Equipment (as defined in Article 25), fire stairways,
perimeter walls, space between the finished ceiling of the Premises and the slab
of the floor or roof of the Property thereabove, and the use thereof together
with the right to install, maintain, operate, repair and replace the Systems and
Equipment, including any of the same in, through, under or above the Premises in
locations that will not materially interfere with Tenant's use of the Premises,
are hereby excepted and reserved by Landlord, and not demised to Tenant.

         (L) "RENT" shall have the meaning specified therefor in Article 3(F).

         (M) "SYSTEMS AND EQUIPMENT" shall mean any plant, machinery,
transformers, duct work, cable, wires, and other equipment, facilities, and
systems designed to supply heat, ventilation, air conditioning and humidity or
any other services or utilities, or comprising or serving as any component or
portion of the electrical, gas, steam, plumbing, sprinkler, communications,
alarm, security, or fire/life/safety systems or equipment, or any other
mechanical, electrical, electronic, computer or other systems or equipment for
the Property.

         (N) "TAXES" shall mean all federal, state, county, or local
governmental or municipal taxes, fees, charges or other impositions of every
kind and nature, whether general, special, ordinary or extraordinary (including
without limitation, real estate taxes, general and special assessments, transit
taxes, water and sewer rents, taxes based upon the receipt of rent including
gross receipts or sales taxes applicable to the receipt of rent or service or
value added taxes (unless required to be paid by Tenant under Article 17),
personal property taxes imposed upon the fixtures, machinery, equipment,
apparatus, Systems and Equipment, appurtenances, furniture and other personal
property used in connection with the Property which Landlord shall pay during
any calendar year, any portion of which occurs during the Term (without regard
to any different fiscal year used by such government or municipal authority)
because of or in connection with the ownership, leasing and operation of the
Property. Notwithstanding the foregoing, there shall be excluded from Taxes all
excess profits taxes, franchise taxes, gift taxes, capital stock taxes,
inheritance and succession taxes, estate taxes, federal and state income taxes,
and other taxes to the extent applicable to Landlord's general or net income (as
opposed to rents, receipts or income attributable to operations at the
Property). If the method of taxation of real estate prevailing at the time of
execution hereof shall be, or has been altered, so as to cause the whole or any
part of the taxes now, hereafter or heretofore levied, assessed or imposed on
real estate to be levied, assessed or imposed on Landlord, wholly or partially,
as a capital levy or otherwise, or on or measured by the rents received
therefrom, then such new or altered taxes attributable to the Property shall be


                                       31
<PAGE>

included within the term "Taxes," except that the same shall not include any
enhancement of said tax attributable to other income of Landlord. Any expenses
reasonably incurred by Landlord in attempting to protest, reduce or minimize
Taxes shall be included in Taxes in the calendar year such expenses are paid.
Tax refunds shall be deducted from Taxes in the year they are received by
Landlord, but if such refund shall relate to taxes paid in a prior year of the
Term, and the Lease shall have expired, Landlord shall mail Tenant's Prorata
Share of such net refund (after deducting expenses and attorneys' fees), up to
the amount Tenant paid towards Taxes during such year, to Tenant's last known
address. If Taxes for any period during the Term or any extension thereof, shall
be increased after payment thereof by Landlord, for any reason including without
limitation error or reassessment by applicable governmental or municipal
authorities, Tenant shall pay Landlord upon demand Tenant's Prorata Share of
such increased Taxes. Tenant shall pay increased Taxes whether Taxes are
increased as a result of increases in the assessment or valuation of the
Property (whether based on a sale, change in ownership or refinancing of the
Property or otherwise), increases in the tax rates, reduction or elimination of
any rollbacks or other deductions available under current law, scheduled
reductions of any tax abatement, as a result of the elimination, invalidity or
withdrawal of any tax abatement, or for any other cause whatsoever.
Notwithstanding the foregoing, if any Taxes shall be paid based on assessments
or bills by a governmental or municipal authority using a fiscal year other than
a calendar year, Landlord may elect to average the assessments or bills for the
subject calendar year, based on the number of months of such calendar year
included in each such assessment or bill.

         (0) "TENANT'S PRORATA SHARE" of Taxes and Operating Expenses shall
be the rentable area of the Premises divided by the rentable area of the
Property on the last day of the calendar year for which Taxes or Operating
Expenses are being determined, excluding any parking facilities. Tenant
acknowledges that the "RENTABLE AREA OF THE PREMISES" under this Lease
includes the usable area, without deduction for columns or projections,
multiplied by a load or conversion factor of eleven percent (11%) for a full
floor, to reflect a share of certain areas, which may include lobbies,
corridors, mechanical, utility, janitorial, boiler and service rooms and
closets, restrooms, and other public, common and service areas. Except as
provided expressly to the contrary herein, the "RENTABLE AREA OF THE
PROPERTY" shall include all rentable area of all space leased or available
for lease at the Property, which Landlord may reasonably redetermine from
time to time, to reflect reconfigurations, additions or modifications to the
Property, provided that Landlord does so on a uniform and consistent basis,
utilizing substantially the same measuring methodology as used to calculate
the area of the Premises as set forth herein. The useable area of the
Premises is 36,908 square feet (18,454 square feet per floor) and the useable
area of the Property is 297,164 square feet. The rentable area of the
Premises and the Property as set forth in this Lease have been determined in
accordance with the Standard Method for Measuring Floor Area in Office
Buildings approved by the American National Standards Institute and the
Building Owners and Managers Association International, adopted 1996. If the
Property or any development of which it is a part, shall contain non-office
uses, Landlord shall have the right to determine in accordance with sound
accounting and management principles, Tenant's Prorata Share of Taxes and
Operation Expenses for only the office portion of the Property or of such
development, in


                                       32
<PAGE>

which event, Tenant's Prorata Share shall be based on the ratio of the rentable
area of the Premises to the rentable area of such office portion. Similarly, if
the Property shall contain tenants who do not participate in all or certain
categories of Taxes or Operating Expenses on a prorata basis, Landlord may
exclude the amount of Taxes or Operating Expenses, or such categories of the
same, as the case may be, attributable to such tenants, and exclude the rentable
area of their premises, in computing Tenant's Prorata Share.

                                   ARTICLE 26
                      CONVEYANCE BY LANDLORD AND LIABILITY

         In case Landlord or any successor owner of the Property or the Building
shall convey or otherwise dispose of any portion thereof in which the Premises
are located, to another Person (and nothing herein shall be construed to
restrict or prevent such conveyance or disposition), such other Person shall
thereupon be and become landlord hereunder and shall be deemed to have fully
assumed and be liable for all obligations of this Lease to be performed by
Landlord which first arise after the date of conveyance, including the return of
any Security Deposit, and Tenant shall attorn to such other Person, and Landlord
or such successor owner shall, from and after the date of conveyance, be free of
all liabilities and obligations hereunder not then incurred. The liability of
Landlord to Tenant for any default by Landlord under this Lease or arising in
connection herewith or with Landlord's operation, management, leasing, repair,
renovation, alteration, or any other matter relating to the Property or the
Premises, shall be limited to the interest of Landlord in the Property. Tenant
agrees to look solely to Landlord's interest in the Property for the recovery of
any judgment against Landlord, and Landlord shall not be personally liable for
any such judgment or deficiency after execution thereon. The limitations of
liability contained in this Article shall apply equally and inure to the benefit
of Landlord's present and future members, partners, beneficiaries, officers,
directors, trustees, shareholders, agents and employees, and their respective
partners, heirs, successors and assigns. Under no circumstances shall any
present or future member of Landlord (if Landlord is a limited liability
company), general or limited partner of Landlord (if Landlord is a partnership),
or trustee or beneficiary (if Landlord or any partner of Landlord is a trust)
have any liability for the performance of Landlord's obligations under this
Lease.

                                   ARTICLE 27
                                 INDEMNIFICATION

         Except to the extent arising from the intentional misconduct or
grossly negligent acts of Landlord or Landlord's agents, contractors or
employees, Tenant shall defend, indemnify and hold harmless Landlord from and
against any and all claims, demands, liabilities, damages, judgments, orders,
decrees, actions, proceedings, fines, penalties, costs and expenses, including
without limitation, court costs and attorneys' fees arising from or relating to
any loss of life, damage or injury to person, property or business occurring in
or from the Premises, or caused by or in connection with any violation of this
Lease or use of the Premises or the Property by, or any other act or omission
of, Tenant,


                                       33
<PAGE>

any other occupant of the Premises, or any of their respective agents,
employees, contractors or guests, or any injury to person or property caused by
Tenant's and its agents, employees, contractors or guests use of the Parking
Spaces. Without limiting the generality of the foregoing, Tenant specifically
acknowledges that the indemnity undertaking herein shall apply to claims in
connection with or arising out of any "Work" as described in Article 8, the
installation, maintenance, use or removal of any "Lines" located in or serving
the Premises as described in Article 29, and the transportation, use, storage,
maintenance, generation, manufacturing, handling, disposal, release or discharge
of any "Hazardous Material" as described in Article 30 (whether or not any of
such matters shall have been theretofore approved by Landlord), except to the
extent that any of the same arises from the intentional misconduct or grossly
negligent acts of Landlord or Landlord's agents or employees.

         Except to the extent arising from the intentional misconduct or
negligent acts of Tenant or Tenant's agents or employees or prohibited by Law,
Landlord shall defend, indemnify and hold Tenant harmless from and against any
and all claims, demands, liabilities, damages, judgments, orders, decrees,
actions, proceedings, fines, penalties, costs and expenses, including without
limitation, court costs and attorneys' fees arising from or relating to any loss
of life, damage or injury to person, property or business occurring in or from
the common area of the Property (expressly excluding the Parking Space), or
caused by or in connection with any negligent act or omission or violation of
this Lease by Landlord, its agents, employees, contractors or guests.

                                   ARTICLE 28
               SAFETY AND SECURITY DEVICES, SERVICES AND PROGRAMS

         The parties acknowledge that safety and security devices, services
and programs provided by Landlord, if any, while intended to deter crime and
ensure safety, may not in given instances prevent theft or other criminal
acts, or ensure safety of persons or property. The risk that any safety or
security device, service or program may not be effective, or may malfunction,
or be circumvented by a criminal, is assumed by Tenant with respect to
Tenant's property and interests, and Tenant shall obtain insurance coverage
to the extent Tenant desires protection against such criminal acts and other
losses, as further described in Article 11. Tenant agrees to cooperate in any
reasonable safety or security program developed by Landlord or required by
Law.

                                   ARTICLE 29
                       COMMUNICATIONS AND COMPUTER LINES

         Tenant may install, maintain, replace, remove or use any communications
or computer wires, cables and related devices (collectively the "LINES") at the
Property in or serving the Premises, provided: (a) Tenant shall obtain
Landlord's prior written consent, use an experienced and qualified contractor
approved in writing by Landlord, and comply with all of the other provisions of
Article 8, (b) any such installation, maintenance,


                                       34
<PAGE>

replacement, removal or use shall comply with all Laws applicable thereto and
good work practices, and shall not interfere with the use of any then existing
Lines at the Property, (c) an acceptable number of spare Lines and space for
additional Lines shall be maintained for existing and future occupants of the
Property, as determined in Landlord's reasonable opinion, (d) if Tenant at any
time uses any equipment that may create an electromagnetic field exceeding the
normal insulation ratings of ordinary twisted pair riser cable or cause
radiation higher than normal background radiation, the Lines therefor (including
riser cables) shall be appropriately insulated to prevent such excessive
electromagnetic fields or radiation, (e) Tenant's rights shall be subject to the
rights of any regulated telephone company, and (f) Tenant shall pay all costs in
connection therewith. Landlord shall at all times maintain exclusive control
over all risers (including, without limitation, their use) located at the
Property. Landlord reserves the right to require that Tenant remove any Lines
located in or serving the Premises which are installed in violation of these
provisions, or which are at any time in violation of any Laws or represent a
dangerous or potentially dangerous condition (whether such Lines were installed
by Tenant or any other party), within ten (10) days after written notice.

         Landlord may (but shall not have the obligation to): (i) install new
Lines at the Property (ii) create additional space for Lines at the Property,
and (iii) reasonably direct, monitor and/or supervise the installation,
maintenance, replacement and removal of, the, allocation and periodic
re-allocation of available space (if any) for, and the allocation of excess
capacity (if any) on, any Lines now or hereafter installed at the Property by
Landlord, Tenant or any other party (but Landlord shall have no right to monitor
or control the information transmitted through such Lines). Such rights shall
not be in limitation of other rights that may be available to Landlord by Law or
otherwise. If Landlord exercises any such rights, Landlord may charge Tenant for
the costs attributable to Tenant, or may include those costs and all other costs
in Operating Expenses under Article 25 (including without limitation, costs for
acquiring and installing Lines and risers to accommodate new Lines and spare
Lines, any associated computerized system and software for maintaining records
of Line connections, and the fees of any consulting engineers and other
experts); provided, any capital expenditures included in Operating Expenses
hereunder shall be amortized (together with reasonable finance charges) over the
period of time prescribed by Article 25.

         Upon termination of this Lease, any Lines owned by Tenant and not
removed by Tenant shall, at Landlord's option, become the property of
Landlord (without payment by Landlord). If Tenant fails to remove such Lines
as required by Landlord, or violates any other provision of this Article,
Landlord may, after twenty (20) days written notice to Tenant, remove such
Lines or remedy such other violation, at Tenant's expense (without limiting
Landlord's other remedies available under this Lease or applicable Law).
Tenant shall not, without the prior written consent of Landlord in each
instance, grant to any third party a security interest or lien in or on the
Lines, and any such security interest or lien granted without Landlord's
written consent shall be null and void. Except to the extent arising from the
intentional or negligent acts of Landlord or Landlord's agents, contractors
or employees, Landlord shall have no liability for damages arising from, and
Landlord does not warrant that the Tenant's use of any Lines will be free
from the following (collectively

                                       35
<PAGE>

called "LINE PROBLEMS"): (x) any eavesdropping or wire-tapping by
unauthorized parties, (y) any failure of any Lines to satisfy Tenant's
requirements, or (z) any shortages, failures, variations, interruptions,
disconnections, loss or damage caused by the installation, maintenance,
replacement, use or removal of Lines by or for other tenants or occupants at
the Property, by any failure of the environmental conditions or the power
supply for the Property to conform to any requirements for the Lines or any
associated equipment, or any other problems associated with any Lines by any
other cause. Under no circumstances shall any Line Problems be deemed an
actual or constructive eviction of Tenant, render Landlord liable to Tenant
for abatement of Rent, or relieve Tenant from performance of Tenant's
obligations under this Lease. Landlord in no event shall be liable for
damages by reason of loss of profits, business interruption or other
consequential damage arising from any Line Problems.

                                   ARTICLE 30
                              HAZARDOUS MATERIALS

         Tenant shall not transport, use, store, maintain, generate,
manufacture, handle, dispose, release or discharge any Hazardous Material upon
or about the Property, nor permit Tenant's employees, agents, contractors, and
other occupants of the Premises to engage in such activities upon or about the
Property. However, the foregoing provisions shall not prohibit the
transportation to and from, and use, storage, maintenance and handling within,
the Premises of substances customarily used in offices (or such other business
or activity expressly permitted to be undertaken in the Premises under Article
6), provided: (a) such substances shall be used and maintained only in such
quantities as are reasonably necessary for such permitted use of the Premises,
strictly in accordance with applicable Law and the manufacturers' instructions
therefor, (b) such substances shall not be disposed of, released or discharged
on the Property, and shall be transported to and from the Premises, and the
Parking Space, in compliance with all applicable Laws, and as Landlord shall
reasonably require, (c) if any applicable Law or Landlord's trash removal
contractor requires that any such substances be disposed of separately from
ordinary trash, Tenant shall make arrangements at Tenant's expense for such
disposal directly with a qualified and licensed disposal company at a lawful
disposal site (subject to scheduling and approval by Landlord), and shall ensure
that disposal occurs frequently enough to prevent unnecessary storage of such
substances in the Premises, and the Parking Space, and (d) any remaining such
substances shall be completely, properly and lawfully removed from the Property
upon expiration or earlier termination of this Lease.

         Tenant shall promptly after becoming aware of same notify Landlord of:
(i) any enforcement, cleanup or other regulatory action taken or threatened by
any governmental or regulatory authority with respect to the presence of any
Hazardous Material on the Premises, or the Parking Space or the migration
thereof from or to other property, (ii) any demands or claims made or threatened
by any party against Tenant, the Premises or the Parking Space relating to any
loss or injury resulting from any Hazardous Material, (iii) any release,
discharge or nonroutine, improper or unlawful disposal or transportation of any
Hazardous Material on or from the Premises or the Parking Space, and (iv) any
matters


                                       36
<PAGE>

where Tenant is required by Law to give a notice to any governmental or
regulatory authority respecting any Hazardous Materials on the Premises or
the Parking Space. Landlord shall have the right (but not the obligation) to
join and participate, as a party, in any legal proceedings or actions
affecting the Premises, or the Parking Space, initiated in connection with
any environmental, health or safety Law. At such times as Landlord may
reasonably request, Tenant shall provide Landlord with a written list
identifying any Hazardous Material then used, stored, or maintained upon the
Premises and the Parking Space of the Building, the use and approximate
quantity of each such material, a copy of any material safety data sheet
("MSDS") issued by the manufacturer therefor, written information concerning
the removal, transportation and disposal of the same, and such other
information as Landlord may reasonably require or as may be required by Law.
The term "HAZARDOUS MATERIAL" for purposes hereof shall mean any chemical,
substance, material or waste or component thereof which is now or hereafter
listed, defined or regulated as a hazardous or toxic chemical, substance,
material or waste or component thereof by any federal, state or local
governing or regulatory body having jurisdiction, or which would trigger any
employee or community "right-to-know" requirements adopted by any such body,
or for which any such body has adopted any requirements for the preparation
or distribution of an MSDS.

         If any Hazardous Material is released, discharged or disposed of by
Tenant or any other occupant of the Premises, or their employees, agents or
contractors, on or about the Property in violation of the foregoing
provisions, Tenant shall immediately, properly and in compliance with
applicable Laws clean up and remove the Hazardous Material from the Property
and any other affected property and clean or replace any affected personal
property (whether or not owned by Landlord), at Tenant's expense. Such clean
up and removal work shall be subject to Landlord's prior written approval
(except in emergencies), and shall include, without limitation, any testing,
investigation, and the preparation and implementation of any remedial action
plan required by any governmental body having jurisdiction or reasonably
required by Landlord. If Tenant shall fail to comply with the provisions of
this Article within five (5) days after written notice by Landlord, or such
shorter time as may be required by Law or in order to minimize any hazard to
Persons or property, Landlord may (but shall not be obligated to) arrange for
such compliance directly or as Tenant's agent through contractors or other
parties selected by Landlord, at Tenant's expense (without limiting
Landlord's other remedies under this Lease or applicable Law). If any
Hazardous Material is released, discharged or disposed of on or about the
Property and such release, discharge or disposal is not caused by Tenant or
other occupants of the Premises, or their employees, agents or contractors,
such release, discharge or disposal shall be deemed casualty damage under
Article 10 to the extent that the Premises, the Parking Space, or common
areas serving the Premises are affected thereby; in such case, Landlord and
Tenant shall have the obligations and rights respecting such casualty damage
provided under Article 10.

         Landlord represents and warrants that, to the best of Landlord's
knowledge, the Property is free of Hazardous Material, provided, however,
this representation and warranty shall not be construed to mean that
Hazardous Materials which are commonly used in the operation and maintenance
of newly constructed office buildings (including,


                                       37
<PAGE>

without limitation, cleaning materials and lubricants) are not present at the
Property. Landlord shall promptly notify Tenant of the presence of Hazardous
Materials in or about the Property if the presence of such Hazardous Materials
presents a risk to the health or property of Tenant or Tenant's employees,
agents, contractors or invitees.

                                   ARTICLE 31
                                 MISCELLANEOUS

         (A) Each of the terms and provisions of this Lease shall be binding
upon and inure to the benefit of the parties hereto, their respective heirs,
executors, administrators, guardians, custodians, successors and assigns,
subject to the provisions of Article 21 respecting Transfers.

         (B) Neither this Lease nor any memorandum of lease or short form lease
shall be recorded by Tenant.

         (C) This Lease shall be construed in accordance with the Laws of the
state in which the Property is located.

         (D) All obligations or rights of either party arising during or
attributable to the period ending upon expiration or earlier termination of this
Lease shall survive such expiration or earlier termination.

         (E) Landlord agrees that, if Tenant timely pays the Rent and performs
the terms and provisions hereunder, and subject to all other terms and
provisions of this Lease, Tenant shall hold and enjoy the Premises during the
Term, free of lawful claims by any Person acting by or through Landlord.

         (F) This Lease does not grant any legal rights to "light and air"
outside the Premises nor any particular view or cityscape visible from the
Premises.

         (G) Tenant shall provide Landlord with a copy of Tenant's audited
financial statements within one hundred twenty (120) days after the end of
Tenant's fiscal year.

         (H) Tenant represents and warrants to Landlord that as of the
Effective Date, there has been no material adverse change in Tenant's financial
condition from the date of the most recent financial statements provided by
Tenant to Landlord.

         (I) Tenant shall have the right to use the fire stairwells between the
floors of the Premises, in accordance with any Rules of the Landlord promulgated
with respect thereto.


                                       38
<PAGE>

                                   ARTICLE 32
                                      OFFER

         The submission and negotiation of this Lease shall not be deemed an
offer to enter the same by Landlord, but the solicitation of such an offer by
Tenant. Tenant agrees that its execution of this Lease constitutes a firm offer
to enter into the same which may not be withdrawn for a period of five (5)
business days after delivery to Landlord (or such other period as may be
expressly provided in any other agreement signed by the parties). During such
period and in reliance on the foregoing Landlord may, at Landlord's option (and
shall, if required by applicable Law), deposit any security deposit and Rent,
and proceed with any plans, specifications, alterations or improvements, and
permit Tenant to enter the Premises, but such acts shall not be deemed an
acceptance of Tenant's offer to enter this Lease, and such acceptance shall be
evidenced only by Landlord signing and delivering this Lease to Tenant.

                                   ARTICLE 33
                                     NOTICES

         Except as expressly provided to the contrary in this Lease, every
notice or other communication to be given by either party to the other with
respect hereto or to the Premises or Property, shall be in writing and shall
not be effective for any purpose unless the same shall be served personally
or by national air courier service, or United States certified mail, return
receipt requested, postage prepaid, addressed, if to Tenant, at the address
first set forth in the Lease, until the Commencement Date, and thereafter to
the Tenant at the Premises, with a copy to McDermott, Will & Emery, 227 West
Monroe Street, Chicago, Illinois 60606, Attention: Gerald M. Offutt, P.C.,
and if to Landlord, at the address at which the last payment of Rent was
required to be made and to Union Tower Investors II, L.L.C., c/o Walton
Street Capital L.L.C., 900 North Michigan Avenue, Suite 1900, Chicago,
Illinois 60611, Attention: Luke G. Massar, or such other address or addresses
as Tenant or Landlord may from time to time designate by notice given as
above provided. Every notice or other communication hereunder shall be deemed
to have been given as of the third business day following the date of such
mailing (or as of any earlier date evidenced by a receipt from such national
air courier service or the United States Postal Service) or immediately if
personally delivered. Notices not sent in accordance with the foregoing shall
be of no force or effect until received by the foregoing parties at such
addresses required herein.

                                   ARTICLE 34
                              REAL ESTATE BROKERS

         Tenant represents that Tenant has dealt only with Development
Resources, Inc., CRES and Binswanger (whose commissions, if any, shall be paid
by Landlord pursuant to separate agreement) as broker, agent or finder in
connection with this Lease and agrees


                                       39
<PAGE>

to indemnify and hold Landlord harmless from all damages, judgments,
liabilities and expenses (including reasonable attorneys' fees) arising from
any claims or demands of any other broker, agent or finder with whom Tenant
has dealt for any commission or fee alleged to be due in connection with its
participation in the procurement of Tenant or the negotiation with Tenant of
this Lease. In addition, Tenant shall indemnify and hold Landlord harmless
from all damages, judgments, liabilities and expenses (including reasonable
attorneys' fees) arising from any claims or demands of CRES for any
commission or fee alleged to be due in connection with its participation in
the procurement of Tenant or the negotiation with Tenant of this Lease,
except for any claim that is based on Landlord's breach of that certain
letter agreement, dated February 8, 2000, from Landlord to Binswanger and
CRES.


                                 ARTICLE 35
                              SECURITY DEPOSIT


         Tenant shall deposit with Landlord a letter of credit (as described
below) in the initial amount of $2,122,242.00 as a security deposit
("SECURITY DEPOSIT"), upon Tenant's execution and submission of this Lease.
The letter of credit shall be a clean, unconditional, stand-by, irrevocable
letter of credit in the initial amount of $2,122,242.00 (which shall be
subject to periodic reductions described below) substantially in the form
attached hereto as EXHIBIT C, issued by a federally insured national banking
association located in Chicago with a net worth in excess of $100,000,000.00
and otherwise reasonably acceptable to Landlord. The letter of credit shall
have an expiration date no earlier than the Expiration Date or shall be
renewed or replaced annually through the Expiration Date, in which event
Tenant shall submit to Landlord original amendments extending the expiration
date of the letter of credit (or replacement letters of credit with extended
expiration dates), on an annual basis no later than the date that is 30 days
prior to the expiration date of the letter of credit then in effect. Failure
to so extend the expiration date of the letter of credit through the
Expiration Date in the foregoing manner shall entitle Landlord to draw down
the letter of credit without notice to Tenant and to hold or apply the
proceeds thereof as a Security Deposit. In the event that Tenant exercises
the Expansion Option (as defined in Article 41), then on the date that
Tenant delivers Landlord the Expansion Option Notice (as defined in Article
41), Tenant shall increase the amount of the letter of credit by an amount
equal to $1,083,519.00, or submit an additional letter of credit in an amount
equal to $1,083,519.00, and shall deliver a replacement letter of credit or
additional letter of credit reflecting such increased amount to Landlord
together with the Expansion Option Notice. Beginning on the anniversary date
of the Commencement Date and on each anniversary date thereafter, and
provided Tenant is not then in default of the Lease beyond any applicable
cure periods, the amount of the letter of credit may be reduced by Tenant as
follows:

                                     40

<PAGE>

<TABLE>
<CAPTION>
Period                          Required Amount                Increased Amount for
------                          (Excluding Expansion Space)    Expansion Space
                                ---------------------------    ---------------
<S>                             <C>                            <C>
Lease Year 1                          $2,122,242.00               $1,083,519.00
Lease Year 2                          $1,994,907.00               $1,018,508.00
Lease Year 3                          $1,846,351.00               $  942,662.00
Lease Year 4                          $1,697,794.00               $  866,815.00
Lease Year 5                          $1,506,792.00               $  769,299.00
Lease Year 6                          $1,315,790.00               $  671,782.00
Lease Year 7                          $1,103,566.00               $  563,430.00
Lease Year 8                          $  870,119.00               $  444,243.00
Lease Year 9                          $  615,450.00               $  314,221.00
Lease Year 10                         $  318,336.00               $  162,528.00
</TABLE>

         The Security Deposit shall serve as security for the prompt, full
and faithful performance by Tenant of the terms and provisions of this Lease.
In the event that Tenant is in Default hereunder and fails to cure within any
applicable time permitted under this Lease, or in the event that Tenant owes
any amounts to Landlord upon the expiration of this Lease which Tenant has
not promptly paid upon demand, Landlord may use or apply the whole or any
part of the Security Deposit for the payment of Tenant's obligations
hereunder. The use or application of the Security Deposit or any portion
thereof shall not prevent Landlord from exercising any other right or remedy
provided hereunder or under any Law and shall not be construed as liquidated
damages. In the event the Security Deposit is reduced by such use or
application, Tenant shall restore the letter of credit to the then required
amount of the Security Deposit, or provide Landlord with additional letters
of credit in the then required amount, within ten (10) days after written
notice.

                                 ARTICLE 36
                       AMERICANS WITH DISABILITIES ACT


        The parties acknowledge that Title III of the Americans With
Disabilities Act of 1990 (42 U.S.C. Section 12101 ET SEQ.) and regulations
and guidelines promulgated thereunder, as all of the same may be amended and
supplemented from time to time (collectively referred to here as the "ADA")
established requirements for accessibility and barrier removal, and that such
requirements may or may not apply to the Premises and Property depending on,
among other things: (1) whether Tenant's business is deemed a "public
accommodation" or "commercial facility", (2) whether such requirements are
"readily achievable", and (3) whether a given alteration affects a "primary
function area" or triggers "path of travel" requirements. The parties hereby
agree that: (a) Landlord shall be responsible for ADA Title III compliance on
the common areas of the Property and in the Building common areas and in the
common area lobby restrooms, (b) Tenant shall be responsible for ADA Title
III compliance in the Premises, and (c) Landlord may perform, or require that
Tenant perform, and Tenant shall be responsible for the cost of, ADA Title
III "path of travel"

                                      41

<PAGE>

requirements triggered by alterations in the Premises. Tenant shall be solely
responsible for requirements under Title I of the ADA relating to Tenant's
employees.

         Landlord represents and warrants that, to the best of Landlord's
knowledge, the common areas of the Property are in compliance with the ADA.

                                   ARTICLE 37
                                OPTION TO EXTEND

         Tenant is hereby granted one (1) option to extend the Term for an
additional period of five (5) consecutive years (the "EXTENSION PERIOD"), on the
same terms and conditions in effect under the Lease immediately prior to the
Extension Period, except that Tenant shall have no further right to extend after
the Extension Period, monthly Base Rent shall be the then Prevailing Rental
Rate, and the Sign Fee (as defined in Article 38) shall be increased as provided
in Article 38. If Tenant exercises an option to extend, such extension shall
apply to the entire Premises, including all Expansion Space that has been added
to the Premises pursuant to Article 37 hereof. The option to extend may be
exercised only by giving Landlord irrevocable and unconditional written notice
thereof (the "EXTENSION NOTICE") no earlier than twenty four (24) months and no
later than fifteen (15) months prior to the commencement of the Extension
Period. Such exercise shall, at Landlord's election, be null and void if Tenant
is in Default under the Lease beyond any applicable cure period at the date of
such notice or at any time thereafter and prior to commencement of the Extension
Period. Upon delivery of the Extension Notice, Tenant shall be irrevocably bound
to lease the Premises for the Extension Period (notwithstanding the absence of
an agreement over the Prevailing Rental Rent [as defined below]).

         For purposes of this Article 37, "PREVAILING RENTAL RATE" means the
average per square foot rental rate per year for all leases for periods
approximately as long as the Extension Period, executed by tenants for similar
uses and lengths of time for similar multistory buildings in the vicinity of the
Property during the six (6) months immediately prior to the date upon which such
Prevailing Rental Rate is determined, where such rates were not set by the terms
of any renewal leases. In all cases, such rates shall take into consideration
the location, quality and age of the building, floor level, extent of leasehold
improvements (existing or to be provided), rental abatements, lease
takeovers/assumptions, parking charges, moving expenses and other concessions
for the benefit of Tenant, term of lease, extent of services to be provided,
distinction between "gross" and "net" lease, base year or amount allowed by
Landlord for payment of building operating expenses (expense stop), and the time
the particular rental rate under consideration became or is to become effective,
or any other relevant term or condition.

         If the parties are unable to agree on the Prevailing Rental Rate within
one hundred eighty (180) days prior to the commencement of the Extension Period,
then the Prevailing Rental Rate shall be determined by appraisal as provided
below (the "APPRAISAL METHOD"). Landlord and Tenant shall attempt to agree on a
single appraiser (the "FIRST


                                       42

<PAGE>

APPRAISER") who shall be a member of the Appraisal Institute, hereinafter
referred to as the "INSTITUTE" (or any successor association or body of
comparable standing if the Institute is not then in existence). If Landlord and
Tenant shall fail to agree on the choice of the First Appraiser within ten (10)
business days after demand by either party, then each shall select an appraiser
within five (5) business days after the expiration of the prior ten (10)
business-day period. If either Landlord or Tenant shall fail to appoint an
appraiser, then the appraiser appointed by the non-appointing party shall select
the second appraiser within five (5) business days after the expiration of the
applicable five (5) business-day period referred to above. The two appraisers
thus selected shall select, within ten (10) business days after their
appointment, a third appraiser (the "THIRD APPRAISER"). If the two appraisers so
selected shall be unable to agree on the selection of the Third Appraiser, then
either appraiser, on behalf of both, shall request such appointment by the
Institute. Any appraiser appointed or selected hereunder shall be a member in
good standing of the Institute and hold the highest general designation of
membership therein. The determination of the Prevailing Rental Rate by the
First Appraiser or the Third Appraiser, if selected as provided herein, shall be
binding on Landlord and Tenant.

         If the parties elect to use the Appraisal Method, the Prevailing Rental
Rate for the Extension Period shall be determined by the First Appraiser or the
Third Appraiser, as applicable, based upon customary and usual appraisal
techniques of expert appraisers as of the scheduled commencement date of the
applicable Extension Period. As used herein, the term "FINAL ARBITER" means the
First Appraiser or, if selected, the Third Appraiser. Each of Landlord and
Tenant shall submit to the Final Arbiter its detailed analysis of its proposed
Prevailing Rental Rate. If either Landlord or Tenant fails to submit a proposed
Prevailing Rental Rate within ten (10) days of the selection or appointment of
the Final Arbiter, then the Prevailing Rental Rate proposed by the party that
has submitted a proposed Prevailing Rental Rate shall be binding on the parties.

         The Final Arbiter shall request in writing that Landlord and Tenant
provide any supplemental information that may be necessary for the Final Arbiter
to render a decision regarding the Prevailing Rental Rate. The Final Arbiter
shall hold a hearing, upon not less than ten (10) days written notice to
Landlord and Tenant, and not later than twenty (20) days following selection of
the Final Arbiter, at which Landlord and Tenant shall have the opportunity to
explain and justify the Prevailing Rental Rate proposed by each party. Any party
not attending such hearing shall have waived its right to defend its proposal at
a hearing. The Final Arbiter shall prepare a written report of his or her
determination of the Prevailing Rental Rate and deliver a copy to Landlord and a
copy to Tenant within thirty (30) days of the selection or appointment of the
Final Arbiter. The Final Arbiter shall select the Prevailing Rental Rate
proposed by either Landlord or Tenant and shall not be entitled to choose any
other Prevailing Rental Rate or to make a determination based upon the average
of the Prevailing Rental Rates proposed by Landlord and Tenant. The
determination of the Final Arbiter shall be final and binding upon the parties.
In no event shall the Prevailing Rental Rate determined by the Final Arbiter for
the Extension Period be less than the Rent payable by Tenant for the immediately
preceding term.


                                       43
<PAGE>

         If the Appraisal Method is used to determine the Prevailing Rental
Rate, then the reasonable fees and expenses of the appraisers involved in the
process, including the fees and expenses of the Final Arbiter, shall be shared
equally by Landlord and Tenant.

         If Tenant shall fail to exercise the option herein provided, such
option shall terminate, and shall be null and void and of no further force and
effect. Tenant's exercise of such option shall not operate to cure any default
by Tenant of any of the terms or provisions in the Lease, nor to extinguish or
impair any rights or remedies of Landlord arising by virtue of such default. If
the Lease or Tenant's right to possession of the Premises shall terminate in any
manner whatsoever before Tenant shall exercise the option herein provided, or if
Tenant shall have subleased or assigned all of the Premises, then immediately
upon such termination, sublease or assignment, the option herein granted to
extend the Term, shall simultaneously terminate and become null and void. Such
option is personal to Tenant and any Related Entity to which all of Tenant's
interest in this Lease has been assigned. Under no circumstances whatsoever
shall the assignee under a partial assignment of the Lease or an assignee, other
than a Related Entity, of an assignment of Tenant's entire interest in the
Lease, or a subtenant under a sublease of the Premises, have any right to
exercise the option to extend granted herein. Time is of the essence of this
provision.

                                   ARTICLE 38
                                     SIGNS

         Subject to the conditions of this Article, Tenant shall have the option
to have a sign bearing its name on the west side of the roof of the Building
(the "ROOF SIGN"). In order to exercise this option, Tenant must give Landlord
written notice thereof (the "SIGN RIGHT NOTICE") on or before March 1, 2000 and
shall pay Landlord the "Sign Fee" as hereafter defined. If Tenant shall fail to
send the Sign Right Notice on or before March 1, 2000, such option shall
terminate, and shall be null and void and of no further force and effect. If
Tenant exercises the option herein provided, Landlord shall install, at Tenant's
cost, the Roof Sign, and Tenant shall maintain same at Tenant's expense, which
maintenance obligation shall be subject to all the provisions of this Lease,
including, without limitation, Article 9. If Tenant fails to maintain same to
Landlord's reasonable satisfaction, Landlord may perform such maintenance and
charge Tenant, as additional Rent, for the costs and expenses incurred by
Landlord in maintaining same. In consideration for the Roof Sign, Tenant shall
pay Landlord either (i) a one-time payment of $750,000.00, which payment shall
be due on the Commencement Date, or (ii) annual payments, each in the amount of
$100,000, with the first such payment due on the Commencement Date and each
subsequent payment due on the first day of each subsequent Lease Year during the
Term. The foregoing payment or payments are referred to herein as the "SIGN
FEE." In the event that Tenant elects to pay the Sign Fee in annual payments and
Tenant exercises the Expansion Option (as defined in Article 41), then the
annual payment due on the first day of the Lease Year occurring after the end of
the tenth Lease Year shall be prorated by multiplying $100,000 by a fraction,
the numerator of which is the number of days from the first day of the Lease
Year occurring after the end of the tenth Lease Year to and including


                                       44
<PAGE>

the Expiration Date, and the denominator of which is 365. Tenant must notify
Landlord in the Sign Right Notice of the payment option for the Sign Fee that
Tenant desires. The following provisions shall apply to Tenant's sign rights:

         (A) All aspects of Tenant's sign, including, without limitation, the
location on the west side of the roof of the Building, size, design,
materials, construction, proposed means of installation, exact location,
illumination, content and color thereof, shall be subject to Landlord's
approval, which shall not be unreasonably withheld except as provided herein,
and all aspects of Tenant's signs shall comply with all applicable Laws,
codes and ordinances. In addition, Landlord shall be entitled to consider the
existence, size and location of other rooftop structures, other signs, and
the proximity of the Roof Sign to the perimeter of the roof in determining
whether to approve the proposed location of the Roof Sign. Tenant shall not
install any sign or make any alterations, additions or improvements to any
sign, until Landlord has approved in writing professionally prepared sign
plans submitted by Tenant showing the design, size, content, color and
quality of materials of the sign, and whether it will be illuminated, and
Tenant has obtained any permits or approvals required by applicable Law.
Landlord may withhold approval of any aspect of the sign plans affecting the
appearance of the Property in Landlord's sole and absolute discretion, but
shall not unreasonably withhold approval of other aspects of the sign plans.
Without limitation on the foregoing, in no event will the Roof Sign contain
flashing or blinking lights or bulbs. In the event that either Landlord or
the City of Chicago do not approve a Roof Sign that is reasonably acceptable
to Tenant, then, prior to installing the Roof Sign, Tenant may elect not to
install a Roof Sign by delivering written notice thereof to Landlord, in
which case Tenant shall have no further right to the Roof Sign, and Landlord
shall promptly return to Tenant the Sign Fee or any portion thereof
previously paid to Landlord. Following the installation of the Roof Sign, no
changes may be made to the Roof Sign without Landlord's prior written
approval.

         (B) The sign rights granted in this Article 38 are personal to Tenant.
Under no circumstances whatsoever shall the assignee under a partial assignment
of the Lease or an assignee of an assignment of Tenant's entire interest in the
Lease, or a subtenant under a sublease of the Premises, have or enjoy any, of
the sign rights granted in this Article 38. Tenant shall have the sign right
with respect to the Roof Sign provided that Tenant and, a Related Entity occupy
at least two (2) floors of the Building. In the event that Tenant assigns,
subleases or terminates such portion or portions of the Premises that Tenant and
a Related Entity no longer occupy at least two (2) floors of the Building, the
rights conferred upon Tenant herein with respect to the Roof Sign shall, at
Landlord's option, terminate and, if Landlord elects to terminate Tenant's right
to the Roof Sign, Tenant shall, at its sole cost, remove the Roof Sign and make
any necessary repairs to the Property caused by the installation or removal of
same. If the rights with respect to the Roof Sign are terminated in accordance
with the preceding sentence, all payments of the Sign Fee prior to such
termination shall be forfeited to Landlord, however, Tenant shall have no
obligation to make any additional payments of the Sign Fee after such
termination. Upon termination of this Lease or Tenant's earlier vacation of the
Premises, Tenant shall, at Tenant's sole cost, remove the Roof Sign and make any
necessary repairs to the Property caused by the installation or removal of same.


                                       45
<PAGE>

         (C) In the event that Tenant fails to pay the Sign Fee as and when due,
and such failure continues for ten (10) days after written notice to Tenant,
then, in addition to any other remedies available in this Lease to Landlord for
a Default by Tenant, Landlord may terminate Tenant's right to maintain the Roof
Sign, in which case Tenant shall remove the Roof Sign, at Tenant's expense,
promptly following receipt of written notice from Landlord to Tenant directing
Tenant to remove the Roof Sign.

         (D) In the event that Tenant exercises the option to extend the Term
pursuant to Article 37, Tenant shall be obligated to pay a Sign Fee during the
Extension Period, in annual installments on the first day of each Lease Year
during the Extension Period, each such payment in an amount equal to
$150,000.00. Notwithstanding the foregoing, Tenant may notify Landlord in the
Extension Notice (as defined in Article 37) that Tenant elects to waive its
right to the Roof Sign during the Extension Period, in which case Tenant shall,
at Tenant's expense, remove the Roof Sign promptly following the beginning of
the Extension Period, and Tenant shall have no further obligation to pay the
Sign Fee during the Extension Period.

         (E) Tenant shall have the right to have Tenant's name and the names of
Tenant's departments and company officers on the Building directory or
directories, at no cost to Tenant. Tenant shall have the right to have Tenant's
name in the lobby of each full floor of the Premises, subject to Landlord's
approval of the format thereof (i.e., the location, size, design, materials,
construction, proposed means of installation, exact location, illumination,
content and color thereof), which approval shall not be unreasonably withheld or
delayed.

         (F) The sign rights provided in this Article 38 are non-exclusive.
Landlord reserves the right to install, or permit other parties to install,
other signs on or about the Property, including the roof of the Building;
provided, however, that Landlord agrees that it will not grant any other party
the right to install a sign on the west side of the roof of the Building.

         (G) In the event that Tenant is required to remove the Roof Sign
pursuant to this Article 38, Tenant shall perform such removal in accordance
with the terms of Article 8 of this Lease, including, without limitation,
submission of plans for such removal for Landlord's approval, and Landlord's
approval of any proposed contractor therefor. In connection with such removal,
Tenant shall make any necessary repairs to the Property caused by the
installation or removal of the Roof Sign.

                                   ARTICLE 39
                              PARKING / GENERATOR

         Landlord hereby grants to Tenant and persons designated by Tenant a
license to use two (2) parking spaces, which shall be increased to three (3)
parking spaces if Tenant exercises the Expansion Option (as defined in Article
41) in the parking area of the Building (the "PARKING SPACES"). Tenant shall
initially pay $225 per month, per parking


                                       46
<PAGE>

space, for the Parking Spaces, which shall be due and payable at the same
time as Base Rent under this Lease. The monthly charge for the Parking Spaces
shall be modified on an annual basis to reflect the prevailing market rate
charged by Landlord for parking spaces in the parking area of the Building.
Tenant shall at all times comply with all Laws respecting Tenant's use of the
parking areas of the Building. Except for intentional acts or negligence,
Landlord shall have no liability whatsoever for any damage to property or any
other items located in the parking areas of the Building, nor for any
personal injuries or death arising out of any matter relating to the parking
areas of the Building and Tenant's use thereof, and in all events, Tenant
agrees to look first to its insurance carrier and to require that Tenant's
employees look first to their respective insurance carriers for payment of
any losses sustained in connection with any use of the parking areas of the
Building. Tenant hereby waives on behalf of its insurance carriers all rights
of subrogation against Landlord or Landlord's agents. Landlord reserves the
right, in accordance with Article 6, to adopt, modify and enforce reasonable
Rules governing the use of the parking areas of the Building, including any
key-card, sticker or other identification or entrance system, and hours of
operation. Landlord may refuse to permit any person who violates such Rules
to park at the Building, and violation of such Rules shall subject the car to
removal from the Property. Landlord reserves the right to assign specific
spaces and to reserve spaces for visitors, small cars, handicapped persons
and for other tenants, guests of tenants or other parties, and Tenant and
persons designated by Tenant hereunder shall not park in any such assigned or
reserved spaces. Landlord also reserves the right to temporarily close all or
any portion of the parking areas in order to make repairs or perform
maintenance services to the Building or the parking areas of the Building, or
to alter, modify, re-stripe or renovate the parking areas. Landlord reserves
the right to monitor Tenant's usage of the Parking Space and remove or refuse
entrance to any vehicles which exceed the number of spaces provided to Tenant
in this Article.

         Tenant may convert the use of the Parking Spaces for placement,
enclosure and connection to the Premises, at Tenant's expense, of Tenant's
back-up generator (the "GENERATOR"), subject to Landlord's reasonable prior
approval of plans and specifications for the Generator and enclosure and
connection to the Premises, and provided that the Generator and all
connections between the Generator, the Building and the Premises (the
"GENERATOR CONNECTIONS") comply at all times with all applicable Laws. Tenant
shall remove the Generator, the enclosure and the Generator Connections from
the Building and the parking area of the Building on the Expiration Date or
earlier termination of this Lease and restore the area to its original
condition, at Tenant's sole cost and expense. Tenant shall be responsible for
the maintenance of the Generator and shall comply with the manufacturer's
recommendations with respect to maintenance and operation thereof. Without
limitation on the foregoing, Tenant shall test the Generator at least once
per month, on weekends.

         The rights to the Parking Spaces provided herein are personal to Tenant
and any Related Entity. Under no circumstance whatsoever shall the assignee
under a complete or partial assignment of the Lease, or a subtenant under a
complete or partial sublease of the Premises, have any rights with respect to
the Parking Spaces.


                                       47
<PAGE>

                                   ARTICLE 40
                               TERMINATION OPTION

         Tenant shall have the option to terminate this Lease as of the date
(the "EARLY EXPIRATION DATE") which is the last day of the fifth (5th) Lease
Year, which option may be exercised only in strict compliance with the terms of
this Article 40. Such option shall be exercised, if at all, by delivery to
Landlord of a notice of termination (the "TERMINATION NOTICE") not less than
fifteen (15) months prior to the Early Expiration Date, and upon payment by
Tenant to Landlord of a fee (the "TERMINATION FEE"). If Tenant does not exercise
the Expansion Option (as defined in Article 41), the Termination Fee shall equal
the sum of (i) $1,319,976.13, plus (ii) three (3) months of "Gross Rent" (as
hereafter defined). If Tenant exercises the Expansion Option, the Termination
Fee shall equal the sum of (i) $1,938,728.90, plus (ii) three (3) months of
Gross Rent. The Termination Notice must be accompanied by a certified or
cashier's check in an amount equal to the Termination Fee. "GROSS RENT" shall
mean the sum of (x) the amount of Monthly Base Rent due and payable as of the
date of the Termination Notice, plus (y) the monthly payments of Tenant's
Prorata Share of Taxes and Operating Expenses due and payable as of the date of
the Termination Notice. If, and only if, Tenant timely and properly delivers the
Termination Notice accompanied by the payment of the Termination Fee, then the
term of this Lease shall end as of the Early Expiration Date, as though the
Early Expiration Date had been originally fixed as the termination date of this
Lease. All terms and conditions of this Lease and Tenant's obligations
hereunder, including, without limitation, Tenant's obligation to pay Rent, shall
continue up to and including the Early Expiration Date. All obligations of
Landlord and Tenant under this Lease not fully performed as of the Early
Expiration Date shall survive the Early Expiration Date. No Transferee, other
than a Related Entity, shall succeed to the rights provided in this Lease to
exercise the Termination Option, any such rights being deemed personal to Tenant
and such Related Entity. The termination option set forth in this Article 40 is
personal to Tenant and any Related Entity to which all of Tenant's interest in
this Lease has been assigned. Under no circumstances whatsoever shall the
assignee under a partial assignment of the Lease or an assignee, other than a
Related Entity, of an assignment of Tenant's entire interest in the Lease, or a
subtenant under a sublease of the Premises, have any right to exercise the
termination option granted herein.

                                   ARTICLE 41
                                EXPANSION OPTION

         Tenant shall have the expansion option set forth in this Article 41
with respect to the "Expansion Space." Landlord hereby grants Tenant the
option (the "EXPANSION OPTION") to lease the entire rentable area of the
fifteenth (15th) floor of the Building (the "EXPANSION SPACE"), consisting of
20,667 rentable square feet, on the same terms and conditions in effect under
the Lease. Tenant shall exercise the Expansion Option by delivering written
notice (the "EXPANSION OPTION NOTICE") of its exercise thereof to

                                       48
<PAGE>

Landlord on or before July 1, 2000, otherwise Tenant shall be deemed to have
waived its right to exercise the Expansion Option. Time shall be of the essence
with respect to Tenant's exercise of the Expansion Option. In the event that
Tenant timely exercises the Expansion Option, the Expansion Space shall be added
to and become a part of the Premises demised under this Lease on the Expansion
Space Commencement Date. The lease term of the Expansion Space shall commence on
the date (the "EXPANSION SPACE COMMENCEMENT DATE") that is the earlier date of
(i) the "Expansion Space Delivery Date," or (ii) Substantial Completion of the
"Expansion Space Work" (as such terms are hereafter defined).

         Tenant's right to exercise the Expansion Option is subject to the
following terms and conditions:

         (i) DELIVERY OF SPACE. Landlord shall perform certain improvements to
the Expansion Space (the "EXPANSION SPACE WORK"), and shall provide Tenant with
an improvement allowance with respect to the Expansion Space Work in an amount
up to $40 per rentable square foot of the Expansion Space. The Expansion Space
Work shall be performed in accordance with the terms of the Work Agreement,
except that Landlord and Tenant shall meet promptly following Landlord's receipt
of the Expansion Option Notice to develop a construction schedule comparable to
the schedule attached to the Work Agreement, which schedule shall provide for
Substantial Completion of the Expansion Space Work on or before November 1,
2000. Landlord and Tenant shall execute a Work Agreement with respect to the
Expansion Space Work that shall conform to the agreed-upon construction
schedule for the Expansion Space Work. The "EXPANSION SPACE DELIVERY DATE" shall
be November 1, 2000, which date shall be extended one day for each day that
Landlord fails to Substantially Complete the Expansion Space Work due to any
reason other than a "Tenant Delay" (as defined in the Work Agreement).

         (ii) MISCELLANEOUS. Tenant's exercise of the Expansion Option shall
not operate to cure any default by Tenant of any of the terms or provisions
in the Lease, nor to extinguish or impair any rights or remedies of Landlord
arising by virtue of such default. If the Lease or Tenant's right to
possession of the Premises shall terminate in any manner whatsoever before
Tenant shall exercise the Expansion Option, or if Tenant shall have subleased
or assigned all or any portion of the Premises other than to a Related
Entity, then immediately upon such termination, sublease or assignment, the
Expansion Option, as the case may be, shall simultaneously terminate and
become null and void. The options set forth in this Article 41 are personal
to Tenant. Under no circumstances whatsoever shall the assignee under a
partial assignment of the Lease or an assignee of Tenant's entire interest in
the Lease, or a subtenant under a sublease of the Premises, have any right to
exercise the option granted herein.

         (iii) TERMS. The Expansion Space shall be leased on the terms and
conditions of this Lease, except (1) the rentable area of the Premises shall
be increased as of the Expansion Space Commencement Date by the rentable area
of the Expansion Space, (2) Tenant's Prorata Share shall be increased as of
the Expansion Space

                                       49
<PAGE>

Commencement Date to reflect the addition of the Expansion Space to the
Premises, (3) the Annual Base Rent due under this Lease shall be increased as of
the Expansion Space Commencement Date by an amount equal to the product of (x)
the rentable square feet of the Expansion Space and (y) the Base Rent Rental
Rate then in effect, and (4) Tenant shall increase the amount of the Security
Deposit required pursuant to Article 35 and deliver Landlord a replacement
letter of credit or an additional letter of credit reflecting such increase
together with the Expansion Option Notice, as more particularly described in
Article 35 hereof. The Base Rent due under this Lease that will be due in the
event that Tenant exercises the Expansion Option is shown on Exhibit A-1. If
Tenant exercises the Expansion Option, the Term of this Lease shall end on the
date that is the last day of the 120th full calendar month following the
Expansion Space Commencement Date, unless sooner terminated in accordance with
the terms of this Lease.

         (iv) DEFAULT. Tenant's exercise of its option with respect to the
Expansion Space shall be null and void if, as of the date of the exercise of the
Expansion Option by Tenant, Tenant is in Default under this Lease.

                                   ARTICLE 42
                                ENTIRE AGREEMENT

         This Lease, together with Rider One, Exhibit A, Exhibit A-1, Exhibit B,
Exhibit C, Exhibit D, Exhibit E and the Work Agreement (WHICH ARE HEREBY
INCORPORATED WHERE REFERRED TO HEREIN AND MADE A PART HEREOF AS THOUGH FULLY SET
FORTH), contains all the terms and provisions between Landlord and Tenant
relating to the matters set forth herein and no prior or contemporaneous
agreement or understanding pertaining to the same shall be of any force or
effect, except any such contemporaneous agreement specifically referring to and
modifying this Lease, signed by both parties. Without limitation as to the
generality of the foregoing, Tenant hereby acknowledges and agrees that
Landlord's leasing agents and field personnel are only authorized to show the
Premises and negotiate terms and conditions for leases subject to Landlord's
final approval, and are not authorized to make any agreements, representations,
understandings or obligations, binding upon Landlord, respecting the condition
of the Premises or Property, suitability of the same for Tenant's business, or
any other matter, and no such agreements, representations., understandings or
obligations not expressly contained herein or in such contemporaneous agreement
shall be of any force or effect. Neither this Lease, nor any Riders or Exhibits
referred to above may be modified, except in writing signed by both parties.


                                       50
<PAGE>

         In witness whereof, Landlord and Tenant have executed this Lease as of
the date first above written.

LANDLORD:                     UNION TOWER INVESTORS II, L.L.C.,
                              a Delaware limited liability company

                              By: Walton Street Real Estate Fund II, L.P.
                                  a Delaware limited partnership, its
                                  managing member

                                  By: Walton Street Managers II, L.P.,
                                      a Delaware limited partnership,
                                      its general partner

                                      By: WSC Managers II, Inc.,
                                          a Delaware corporation,
                                          its general partner

                                          By: /s/ Howard J. Brody
                                              ------------------------
                                          Name: Howard J. Brody
                                               -----------------------
                                          Title:  V.P
                                                ----------------------


TENANT:                       PARTICIPATE.COM, INC.,
                              a Delaware corporation

                              By: /s/ Stephen J. Hawrysz
                                 -----------------------------
                              Name:   Stephen J. Hawrysz
                                   ---------------------------
                              Title: CFO
                                    --------------------------


                                       51
<PAGE>

                            CERTIFICATE OF AUTHORITY

         I, Alan K. Warms, Secretary of PARTICIPATE.COM hereby certify that
Stephen J Hawrysz the officer executing the foregoing Lease on behalf of
Tenant was duly authorized to act in his capacities as Chief Financial
Officer of Participate.com, and his action is the action of Tenant.

(Corporate Seal)                                  /s/ Alex K. Warms
                                        ----------------------------------
                                                     Secretary


                                       1
<PAGE>

                                   RIDER ONE

                                     RULES

         (1) On Saturdays, Sundays and Holidays, and on other days between the
hours of 6:00 P.M. and 8:00 A.M. the following day, or such other hours as
Landlord shall determine from time to time, access to the Property and/or to the
passageways, entrances, exits, shipping areas, halls, corridors, elevators or
stairways and other areas in the Property may be restricted and access gained by
use of a key to the outside doors of the Property, or pursuant to such security
procedures Landlord may from time to time reasonably impose. All such areas, and
all roofs, are not for use of the general public and Landlord shall in all cases
retain the right to control and prevent access thereto by all persons whose
presence in the reasonable judgment of Landlord shall be prejudicial to the
safety, character, reputation and interests of the Property and its tenants
provided, however, that nothing herein contained shall be construed to prevent
such access to persons with whom Tenant deals in the normal course of Tenant's
business unless such persons are engaged in activities which are illegal or
violate these Rules. No Tenant and no employee or invitee of Tenant shall enter
into areas reserved for the exclusive use of Landlord, its employees or
invitees. Tenant shall keep doors to corridors and lobbies closed except when
persons are entering or leaving.

         (2) Tenant shall not paint, display, inscribe, maintain or affix any
sign, placard, picture, advertisement, name, notice, lettering or direction on
any part of the outside or inside of the Property, or on any part of the inside
of the Premises which can be seen from the outside of the Premises, without the
prior consent of Landlord, and then only such name or names or matter and in
such color, size, style, character and material as may be first approved by
Landlord in writing. Landlord reserves the right, upon prior notice to Tenant,
to remove at Tenant's expense all matter not so installed or approved without
notice to Tenant.

         (3) Tenant shall not in any manner use the name of the Property for any
purpose other than that of the business address of the Tenant, or use any
picture or likeness of the Property, in any letterheads, envelopes, circulars,
notices, advertisements, containers or wrapping material without Landlord's
express consent in writing.

         (4) Tenant shall not place anything or allow anything to be placed in
the Premises near the glass of any door, partition, wall or window which may be
unsightly from outside the Premises, and Tenant shall not place or permit to be
placed any article of any kind on any window ledge or on the exterior walls.
Blinds, shades, awnings or other forms of inside or outside window ventilators
or similar devices, shall not be placed in or about the outside windows in the
Premises except to the extent, if any, that the character, shape, color,
material and make thereof is first approved by the Landlord.

         (5) Furniture, freight and other large or heavy articles, and all other
deliveries may be brought into the Property only at times and in the manner
reasonably designated by Landlord, in compliance with all Laws, and always at
the Tenant's sole responsibility


                                       1
<PAGE>

and risk. Landlord may impose reasonable charges for use of freight elevators
after or before normal business hours (which charges shall be generally imposed
on tenants of the Building and shall be available in the office of the Building,
and shall be subject to adjustment from time to time). All damage done to the
Property by moving or maintaining such furniture, freight or articles shall be
repaired by Landlord at Tenant's expense. Landlord may inspect items brought
into the Property or Premises with respect to weight or dangerous nature.
Landlord may require that all furniture, equipment, cartons and similar articles
removed from the Premises or the Property be listed and a removal permit
therefor first be obtained from Landlord. Tenant shall not take or permit to be
taken in or out of other entrances or elevators of the Property, any item
normally taken, or which Landlord otherwise reasonably requires to be taken, in
or out through service doors or on freight elevators. Tenant shall not allow
anything (including without limitation, portable carts, signs, placards, and
billboards) to remain in or obstruct in any way, any lobby, plaza, corridor,
sidewalk, passageway, entrance, exit, hall, elevator, escalator, stairway,
shipping area, or other area. Tenant shall move all supplies, furniture and
equipment as soon as received directly to the Premises, and shall move all such
items and waste that are at any time being taken from the Premises directly to
the areas designated for disposal. Tenant shall cause trash and rubbish to be
deposited only in receptacles approved or designated by Landlord. Any hand-carts
used at the Property shall have rubber wheels and side guards and no other
material handling equipment may be brought upon the Property, except as Landlord
shall approve in writing in advance.

         (6) Tenant shall not overload any floor or part thereof in the
Premises, or Property, including any public corridors or elevators therein
bringing in or removing any large or heavy articles, and Landlord may direct and
control the location of safes and all other heavy articles and require
supplementary supports at Tenant's expense of such material and dimensions as
Landlord may deem necessary to property distribute the weight.

         (7) Tenant shall not attach or permit to be attached additional locks
or similar devices to any door or window, change existing locks or the mechanism
thereof, or make or permit to be made any keys for any door other than those
provided by Landlord. If more than two keys for one lock are desired, Landlord
will provide them upon payment therefor by Tenant. Tenant, upon termination of
its tenancy, shall deliver to the Landlord all keys of offices, rooms and toilet
rooms which have been furnished Tenant or which the Tenant shall have had made,
and in the event of loss of any keys so furnished shall pay Landlord therefor
(at the rates that are generally imposed on tenants of the Building, which shall
be available in the office of the Building, and shall be subject to adjustment
from time to time).

         (8) If Tenant desires signal, communication, alarm or other utility or
similar service connections installed or changed, Tenant shall not install or
change the same without the prior approval of Landlord, and then only under
Landlord's direction at Tenant's expense. Tenant shall not install in the
Premises any equipment which requires more electric current than Landlord is
required to provide under this Lease, without Landlord's prior approval, and
Tenant shall ascertain from Landlord the maximum amount of load or


                                       2
<PAGE>

demand for or use of electrical current which can safely be permitted in the
Premises, taking into account the capacity of electric wiring in the Property
and the Premises and the needs of tenants of the Property, and shall not in any
event connect a greater load than such safe capacity.

         (9) Tenant shall not obtain for use upon the Premises ice, drinking
water, towel, janitor and other similar services, except from Persons approved
by the Landlord. Any Person engaged by Tenant to provide janitor or other
services shall be subject to direction by the manager or security personnel of
the Property.

         (10) The toilet rooms, urinals, wash bowls and other such apparatus
shall not be used for any purpose other than that for which they were
constructed and no foreign substance of any kind whatsoever shall be thrown
therein and the expense of any breakage, stoppage or damage resulting from the
violation of this Rule shall be borne by the Tenant who, or whose employees or
invitees shall have caused it.

         (11) The janitorial closets, utility closets, telephone closets, broom
closets, electrical closets, storage closets, and other such closets, rooms and
areas shall be used only for the purposes and in the manner designated by
Landlord, and may not be used by tenants, or their contractors, agents,
employees, or other parties without Landlord's prior written consent. With
respect to telephone risers, Landlord requires the Tenant to contract with the
approved Building telephone riser management company for all telephone cabling
extending from within the main telephone room (Netpop) up to a demarcation point
located in the Tenant's premises.

         (12) Landlord reserves the right to exclude or expel from the Property
any person who, in the reasonable judgment of Landlord, is intoxicated or under
the influence of liquor or drugs, or who shall in any manner do any act in
violation of any of these Rules. Tenant shall not at any time manufacture,
sell, use or give away, any spirituous, fermented, intoxicating or alcoholic
liquors on the Premises, nor permit any of the same to occur (except in
connection with occasional social or business events conducted in the Premises
which do not violate any Laws nor bother or annoy any other tenants). Tenant
shall not at any time sell, purchase or give away, food in any form by or to
any of Tenant's agents or employees or any other parties on the Premises, nor
permit any of the same to occur (other than in lunch rooms or kitchens for
employees as may be permitted or installed by Landlord, which does not violate
any Laws or bother or annoy any other tenant, and except in connection with
occasional social or business events conducted in the Premises which do not
violate any Laws nor bother or annoy any other tenants). Tenant shall not permit
any pinball or other similar video or electronic machines on the Premises
without Landlord's prior written consent, which consent shall not be
unreasonably withheld if such machine will not bother or annoy any other
tenants. Nothing contained in the preceding sentence shall prohibit Tenant from
permitting the use of video games on computer monitors or televisions (such as
Nintendo). If any food or beverages shall be permitted to be sold or consumed on
the Premises, and Landlord believes in good faith that the sale or consumption
of food or beverages has caused or will cause infestation of the Premises or the
Property with rodents or vermin, Landlord may require that Tenant engage a


                                       3
<PAGE>

responsible pest and rodent control service approved by Landlord on such regular
basis as Landlord reasonably requires.

         (13) Tenant shall not make any room-to-room canvass to solicit business
or information or to distribute any article or material to or from other tenants
or occupants of the Property and shall not exhibit, sell or offer to sell, use,
rent or exchange any products or services in or from the Premises unless
ordinarily embraced within the Tenant's use of the Premises specified in the
Lease. No leaflets or other materials may be distributed or placed on vehicles
in any parking area or facility.

         (14) Tenant shall not waste electricity, water, heat or air
conditioning or other utilities or services, and agrees to cooperate fully with
Landlord to assure the most effective and energy efficient operation of the
Property and shall not allow the adjustment (except by Landlord's authorized
Property personnel) of any controls. Tenant shall keep corridor doors closed and
shall not open any windows, except that if the air circulation shall not be in
operation, windows which are openable may be opened with Landlord's consent. As
a condition to claiming any deficiency in the air-conditioning or ventilation
services provided by Landlord, Tenant shall close any blinds or drapes in the
Premises to prevent or minimize direct sunlight.

         (15) Tenant shall conduct no auction, fire or "going out of business
sale" or bankruptcy sale in or from the Premises, and such prohibition shall
apply to Tenant's creditors.

         (16) Tenant shall cooperate and comply with any reasonable safety or
security programs, including fire drills and air raid drills, and the
appointment of "fire wardens" developed by Landlord for the Property, or
required by Law. Before leaving the Premises unattended, Tenant shall close
and securely lock all doors or other means of entry to the Premises and shut
off all water faucets in the Premises (except heat to the extent necessary to
prevent the freezing or bursting of pipes).

         (17) Intentionally Deleted.

         (18) Tenant shall not (i) carry on any business, activity or service
except those ordinarily embraced within the permitted use of the Premises
specified in the Lease and more particularly, but without limiting the
generality of the foregoing, shall not (ii) install or operate any internal
combustion engine, boiler, machinery, refrigerating, heating or air
conditioning equipment in or about the Premises, (iii) use the Premises for
housing, lodging or sleeping purposes or for the washing of clothes, (iv) place
any radio or television antennae other than inside of the Premises, (v) operate
or permit to be operated any musical or sound producing instrument or device
which may be heard outside the Premises, (vi) use any source of power other than
electricity, (vii) operate any electrical or other device from which may emanate
electrical or other waves which may interfere with or impair radio, television,
microwave, or other broadcasting or reception from or in the Property or
elsewhere, (viii) bring or permit any bicycle or other vehicle, or dog (except
in the company of a blind person or except where specifically permitted) or
other animal or


                                       4
<PAGE>

bird in the Property, (ix) make or permit objectionable noise or odor to
emanate from the Premises, (x) do anything in or about the Premises tending
to create or maintain a nuisance or do any act tending to injure the
reputation of the Property, (xi) throw or permit to be thrown or dropped any
article from any window or other opening in the Property, (xii) use or permit
upon the Premises anything that will invalidate or increase the rate of
insurance on any policies of insurance now or hereafter carried on the
Property or violate the certificates of occupancy issued for the premises or
the Property, (xiii) use the Premises for any purpose, or permit upon the
Premises anything, that may be dangerous to persons or property (including
but not limited to flammable oils, fluids, paints, chemicals, firearms or any
explosive articles or materials) nor (xiv) do or permit anything to be done
upon the Premises in any way tending to disturb any other tenant at the
Property or the occupants of neighboring property.

         (19) If the Property shall now or hereafter contain a building
garage, parking structure or other parking area or facility, the Rules set
forth below shall apply in such areas or facilities. In the event of any
conflict between the Rules set forth below and the terms of Article 41, the
provisions of Article 41 shall govern.

                  (i)      Parking shall be available in areas designated
                           generally for tenant parking, for such daily or
                           monthly charges as Landlord may establish from time
                           to time, or as may be provided in any Parking
                           Agreement attached hereto (which, when signed by both
                           parties as provided therein, shall thereupon become
                           effective). In all cases, parking for Tenant and its
                           employees and visitors shall be on a "first come,
                           first served," unassigned basis, with Landlord and
                           other tenants at the Property, and their employees
                           and visitors, and other Persons (as defined in
                           Article 25 of the Lease) to whom Landlord shall grant
                           the right or who shall otherwise have the right to
                           use the same, all subject to these Rules, as the same
                           may be amended or supplemented, and applied on a
                           non-discriminatory basis, all as further described in
                           Article 6 of the Lease. Notwithstanding the foregoing
                           to the contrary, Landlord reserves the right to
                           assign specific spaces, and to reserve spaces for
                           visitors, small cars, handicapped individuals, and
                           other tenants, visitors of tenants or other Persons,
                           and Tenant and its employees and visitors shall not
                           park in any such assigned or reserved spaces.
                           Landlord may restrict or prohibit full size vans
                           and other large vehicles.

                  (ii)     In case of any violation of these provisions,
                           Landlord may refuse to permit the violator to park,
                           and may remove the vehicle owned or driven by the
                           violator from the Property without liability
                           whatsoever, at such violator's risk and expense.
                           Landlord reserves the right to close all or a portion
                           of the parking areas or facilities in order to make
                           repairs or perform maintenance services, or to alter,
                           modify, re-stripe or renovate the same, or if
                           required by casualty, strike, condemnation, act of
                           God, Law or governmental requirement, or any


                                       5
<PAGE>

                           other reason beyond Landlord's reasonable control. In
                           the event access is denied for any reason, any
                           monthly parking charges shall be abated to the extent
                           access is denied, as Tenant's sole recourse, Tenant
                           acknowledges that such parking areas or facilities
                           may be operated by an independent contractor not
                           affiliated with Landlord, and Tenant acknowledges
                           that in such event, Landlord shall have no liability
                           for claims arising through acts or omissions of such
                           independent contractor, if such contractor is
                           reputable.

                  (iii)    Regular hours shall be 6 A.M. to 8 P.M., Monday
                           through Friday, and 10:00 A.M. to 1:00 P.M. on
                           Saturdays, or such other hours as may be reasonably
                           established by Landlord or its parking operator from
                           time to time, provided, however, Landlord shall make
                           arrangements for Tenant to have access to and use of
                           the parking garage twenty-four hours per day; cars
                           must be parked entirely within the stall lines, and
                           only small cars may be parked in areas reserved for
                           small cars; all directional signs and arrows must be
                           observed; the speed limit shall be 5 miles per hour;
                           spaces reserved for handicapped parking must be used
                           only by vehicles properly designated; every parker is
                           required to park and lock his own car; washing,
                           waxing, cleaning or servicing of any vehicle is
                           prohibited; Parking Space may be used only for
                           parking automobiles; parking is prohibited in areas:
                           (a) not striped or designated for parking,
                           (b) aisles, (c) where "no parking" signs are posted,
                           (d) on ramps, and (e) loading areas and other
                           specially designated areas. Delivery trucks and
                           vehicles shall use only those areas designated
                           therefor.


                                       6
<PAGE>

                                   EXHIBIT A

                                   BASE RENT

<TABLE>
<CAPTION>
                            BASE RENT               ANNUAL                       MONTHLY
LEASE YEAR                  RENTAL RATE             BASE RENT                    BASE RENT
----------                  -----------             ---------                    ---------

<S>                         <C>                     <C>                          <C>
-----------------------------------------------------------------------------------------------------------
           1                    $   28.00                 $   1,157,352.00                 $    96,446.00
-----------------------------------------------------------------------------------------------------------
           2                    $   28.50                 $   1,178,019.00                 $    98,168.25
-----------------------------------------------------------------------------------------------------------
           3                    $   29.00                 $   1,198,686.00                 $    99,890.50
-----------------------------------------------------------------------------------------------------------
           4                    $   29.50                 $   1,219,353.00                 $   101,612.75
-----------------------------------------------------------------------------------------------------------
           5                    $   30.00                 $   1,240,020.00                 $   103,335.00
-----------------------------------------------------------------------------------------------------------
           6                    $   30.50                 $   1,260,687.00                 $   105,057.25
-----------------------------------------------------------------------------------------------------------
           7                    $   31.00                 $   1,281,354.00                 $   106,779.50
-----------------------------------------------------------------------------------------------------------
           8                    $   31.50                 $   1,302,021.00                 $   108,501.75
-----------------------------------------------------------------------------------------------------------
           9                    $   32.00                 $   1,322,688.00                 $   110,224.00
-----------------------------------------------------------------------------------------------------------
          10                    $   32.50                 $   1,343,355.00                 $   111,946.25
-----------------------------------------------------------------------------------------------------------

-----------------------------------------------------------------------------------------------------------

-----------------------------------------------------------------------------------------------------------
</TABLE>


                                   Exhibit A
<PAGE>

                                  EXHIBIT A-1

                                  BASE RENT IF
                     TENANT EXERCISES THE EXPANSION OPTION

<TABLE>
<CAPTION>
                            BASE RENT               ANNUAL                       MONTHLY
LEASE YEAR                  RENTAL RATE             BASE RENT                    BASE RENT
----------                  -----------             ---------                    ---------

<S>                         <C>                     <C>                          <C>
-----------------------------------------------------------------------------------------------------------
           1                    $   28.00                 $   1,736,028.00                 $   144,669.00
-----------------------------------------------------------------------------------------------------------
           2                        28.50                 $   1,767,028.50                 $   147,252.38
-----------------------------------------------------------------------------------------------------------
           3                    $   29.00                 $   1,798,029.00                 $   149,835.75
-----------------------------------------------------------------------------------------------------------
           4                    $   29.50                 $   1,829,029.50                 $   152,419.13
-----------------------------------------------------------------------------------------------------------
           5                    $   30.00                 $   1,860,030.00                 $   155,002.50
-----------------------------------------------------------------------------------------------------------
           6                    $   30.50                 $   1,891,030.50                 $   157,585.88
-----------------------------------------------------------------------------------------------------------
           7                    $   31.00                 $   1,922,031.00                 $   160,169.25
-----------------------------------------------------------------------------------------------------------
           8                    $   31.50                 $   1,953,031.50                 $   162,752.63
-----------------------------------------------------------------------------------------------------------
           9                    $   32.00                 $   1,984,032.00                 $   165,336.00
-----------------------------------------------------------------------------------------------------------
          10                    $   32.50                 $   2,015,032.50                 $   167,919.38
-----------------------------------------------------------------------------------------------------------
From the end of the 10th
Lease Year to the               $   33.00                 $   2,046,033.00                 $   170,502.75
Expiration Date
-----------------------------------------------------------------------------------------------------------
</TABLE>


                                  Exhibit A-1
<PAGE>

                                   EXHIBIT B

                       EXCLUSIONS FROM OPERATING EXPENSES

The following expenses are excluded from Building Operating Expenses:

1.       all costs related to Year 2000 compliance;

2.       the cost of making an installation or alteration to the Building which
         under generally accepted accounting principles is properly classified
         as a capital expenditure, in which event such item shall be
         capitalized;

3.       advertising expenses;

4.       expenses incurred by Landlord to paint, decorate or redecorate any
         space leased to a tenant of the Building;

5.       costs of repairing latent defects in the original construction of the
         Building or in the construction of the Base Building Work;

6.       expenses for any item or service provided exclusively to other tenants
         at the Property and not provided to Tenant.

7.       expenses incurred by Landlord for repairs or other work occasioned by
         fire, windstorm, or other insurable casualty or condemnation;

8.       rental payments on any ground or underlying lease for the Property
         (except rental payments which constitute reimbursement for Taxes);

9.       any cost representing an amount paid for services or materials to a
         related person, firm or entity to the extent such amount exceeds the
         amount that would be paid for such services or materials at the then
         existing market rates to an unrelated person, firm or entity;

10.      expenses for the repair or maintenance of any item to the extent
         covered under warranty or service contract (excluding any mandatory
         deductible);

11.      legal fees incurred in connection with the construction of the
         Building;

12.      all expenses related to the remediation, clean-up or any other action
         taken with respect to any environmental contamination or other
         environmental problem at the Building; and


                                  Exhibit B-1
<PAGE>

13.      Costs to bring the Property into compliance with the ADA.

14.      Costs or expenses of utilities directly metered to tenants of the
         Building and payable separately by such tenants.

15.      Costs and expenses of any special events (e.g., receptions and
         concerts) for which Landlord charges a fee or receives compensation.

16.      Charitable or political contributions by Landlord.

I7.      Costs, other than those incurred in ordinary maintenance, for
         sculpture, paintings or other objects of art.

18.      Costs incurred in connection with the sale, financing, refinancing, or
         change in ownership of the Building.


                                   Exhibit B-2
<PAGE>

                                   EXHIBIT C

                            FORM OF LETTER OF CREDIT



                                  Exhibit C-1
<PAGE>

                                   EXHIBIT D

                     CLEANING AND JANITORIAL SPECIFICATIONS



                                    Exhibit D
<PAGE>


                                  UNION TOWER
                           550 WEST VAN BUREN STREET

                            CLEANING SPECIFICATIONS

I. MAIN ENTRANCES AND LOBBY AREAS

     A. NIGHTLY

          1.  Dust-sweep and wash hard surfaced flooring. Remove gum, tar, and
              other foreign matter from flooring.

          2.  Power scrub granite and similar flooring using materials
              recommended by granite installer.

          3.  If floor mats have been used during the day, they shall be
              thoroughly vacuumed, cleaned and scrubbed if necessary.

          4.  Clean cigarette urns and replace sand or water as needed.

          5.  Dust baseboards, trim, louvers, molding, pictures, planter
              furnishings, guard stations, ledges and all other fixtures.

          6.  Clean building directory and all other decorative metal; as
              needed using a cloth dampened with water only.

          7.  Completely clean all entrance and revolving door glass and entry
              way glass sidelights; clean all glass in building directory.

          8.  Empty and clean waste receptacles and remove waste material to
              designated areas in the building. Dispose of waste and replace
              plastic liners in accordance with building's recycling program.

          9.  Remove dirt, finger marks, smudges, etc. from doors, door
              frames, walls up to twelve feet, switch plates, glass, push
              plates, handles, railings, moldings, trim, etc. Damp wipe metal
              trim as necessary using water only.

          10. Clean public telephones with spray germicidal product and
              disposable paper wipes, which will be disposed of after use on
              each telephone. Dust the phone case and booth using a cloth
              dampened with water only.

          11. Clean lights, globes, fixtures and replace tubes and/or bulbs
              as necessary using tubes and/or bulbs supplied by Owner.

<PAGE>

     B. MONTHLY

          1.  Using materials recommend by granite installer, machine strip,
              refinish and buff granite and similar flooring using
              non-staining, non-slip, recommended floor finish as necessary
              but not less frequently than once per month.

          2.  Do high dusting (as specified under office areas).

     C. YEARLY

          1.  Completely clean floor mats as necessary, but not less than
              three times per year, using method(s) recommended by floor mat
              manufacturer(s).

          2.  Wash all wood, granite and other similar wall surfaces, using
              manufacturers recommendations twice per year.

          3.  Clean lights, globes, fixtures and replace tubes and/or bulbs
              as necessary using tubes and/or bulbs supplied by Owner twice
              per year.

II. ELEVATOR LOBBIES AND PUBLIC CORRIDORS

     A. NIGHTLY

          1.  Dust sweep hard surfaced flooring with specially treated cloths
              to insure dust free floors.

          2.  Wash and machine scrub granite, etc. flooring.

          3.  Thoroughly vacuum and remove spots and stains from carpeting,
              including edges and corners.

          4.  Empty and clean waste receptacles in accordance with building's
              recycling program (replace plastic liners), ash trays, etc.;
              empty and clean cigarette urns and replace sand or water as
              needed.

          5.  Dust baseboards, trim, louvers, moldings, pictures, doors,
              plants and all other fixtures, etc. within reach. Wipe clean
              all signage.

          6.  Remove dirt, finger marks, smudges, etc. from doors, door
              frames, walls, switch plates, glass, push plates, handles,
              railings, moldings, trim, etc. Wipe metal trim as necessary
              using water only.

          7.  Clean lights, globes, fixtures and replace tubes and/or bulbs
              as necessary using tubes and/or bulbs supplied by Owner.

          8.  Clean, polish and sanitize all drinking fountains and water
              coolers using approved germicidal detergent solution.

<PAGE>

     B. MONTHLY

          1.  Power pile lift carpeting twice per month.

          2.  Machine strip, refinish and buff resilient tile, terrazzo,
              granite, etc. flooring using approved non-slip, non-staining,
              recommended floor finish once every two months.

          3.  Do high dusting (as specified under office areas) once every
              two months.

          4.  Completely clean carpeting using method(s) recommended by
              carpet manufacturer(s) once every three months.

          5.  Wash wood, granite and other similar wall surfaces once every
              six months.

III. REST ROOMS

     A. NIGHTLY

          1.  Sweep and wash flooring with approved germicidal detergents at
              strengths.

          2.  Wash and polish mirrors, and all chrome and other bright work
              including shelves, flushometers, exposed piping, toilet
              partition hinges, dispensers, and all other washroom fixtures.

          3.  Wash all surfaces of toilets and urinals with approved
              germicidal detergent solution at disinfectant strength. Bowl
              cleaner to be used in the interior. Remove hard water stains
              from toilet fixtures by using one ounce of bowl cleaner after
              normal cleaning. Follow manufacturer's recommendations.

          4.  Wash clean all wash basins and counter tops, following
              manufacturer's recommendations.

          5.  Spot clean partitions, tile walls, and doors with special
              attention to areas behind sinks, around urinals and around
              entrance. Remove graffiti.

          6.  Empty and clean towel and sanitary disposal receptacles and
              waste material and refuse to designated area in the building
              using janitor carts/carriages. Replace liners in all
              receptacles with liners. Wash clean receptacles.

          7.  Clean and flush floor and other drains using germicidal
              solutions.

          8.  Clean lights, globes, fixtures and replace tubes and/or bulbs
              as necessary using tubes and/or bulbs supplied by Owner.

          9.  Refill all hand towel, toilet tissue and soap dispensers
              nightly, supplied by Owner.






<PAGE>

     B.   WEEKLY

          1.   Wash partitions, tile walls and enamel painted surfaces with
               approved germicidal detergent solution once per week.

     C.   MONTHLY

          1.   Machine scrub flooring with approved germicidal detergent
               solution. Floors shall be cleaned per manufacturer's
               recommendations.

          2.   Do high dusting and damp wipe ceiling vents.

IV.  STAIRWAYS

     A.   NIGHTLY

          1.   Police stairwells and remove trash and debris.

          2.   Spot clean doors and walls.

          3.   Clean lights, globes, fixtures and replace tubes and/or bulbs as
               necessary using tubes and/or bulbs supplied by Owner.

     B.   WEEKLY

          1.   Dust mop stairs and landings, dust handrails and other
               horizontal surfaces.

     C.   MONTHLY

          1.   Dust all vertical surfaces and light fixtures not dusted weekly.

          2.   Wash stairs and landings.

          3.   Do high dusting (as defined in office areas) in stairwells once
               every three months.

          4.   Seal stair treads and risers once every three months.

V.   ELEVATORS

     A.   NIGHTLY

          1.   Floors in elevator cabs will be properly maintained. Vacuum and
               remove spots from carpeted areas and sweep and wash hard
               surfaces.

          2.   Clean and polish doors, inside and outside using a cloth
               dampened with water only.

          3.   Clean elevator saddles, door tracks, etc. keeping them free
               from dirt and debris,

<PAGE>

               polish regularly as needed.

          4.   Hand clean trim, railings, etc. using a cloth dampened with
               water only on all bronze surfaces.

          5.   Keep walls, panels, etc. clean and free from finger marks and
               smudges by method recommended by the manufacturer.

     B.   WEEKLY

          1.   Clean carpeting by method recommended by manufacturer as
               necessary but not more frequently than.

VI. GARAGE, BUILDING SERVICE AREAS & BUILDING EXTERIOR

     A.   NIGHTLY

          1.   Keep locker rooms, rest rooms, engineer's offices, security,
               dock office, etc. (if applicable) in neat and clean condition
               at all times.

          2.   Keep janitor closets in neat and clean condition. Clean slop
               sinks. Mops, rags, and equipment to be cleaned and stored
               properly. Walls and floors to be kept clean.

          3.   Sweep dock, garage area, service corridor and receiving area
               and remove all trash and debris.

          4.   Compactor areas to be swept and hosed down nightly; pressure
               wash as necessary.

          5.   Remove trash and debris from plazas, sweep or hose down as
               necessary; remove gum, tar, etc. on sight.

          6.   Sweep and hose down sidewalks (weather permitting), remove gum,
               and clean out tree wells. Wipe down all granite and stone ledges
               within reach.

          7.   Telephone closets, hose rooms and storerooms are to be kept
               free from debris and rubbish. Report storage of extraneous
               material and equipment to Building Management.

          8.   Squeegee water pooling in plaza areas and walkways as needed.

          9.   Shovel snow during and immediately after snowfall and put down
               appropriate ice melting materials provided by Owner. Remove snow
               from sidewalks and curbs around entire property as needed.

          10.  Wash flooring in dock, service corridors and receiving area.

          11.  Machine scrub or pressure wash dock, service corridors and
               receiving area as needed.

<PAGE>


          12.  Police entire site in accordance with the City's "Adopt a
               Street Program" as needed.

          13.  Sweep garage area and remove all trash and debris.

     B.   WEEKLY

          1.   Machine scrub or pressure wash sidewalks and plaza area
               (weather permitting).

     C.   MONTHLY

          1.   Seal service corridors.

          2.   Clean and dust vertical surfaces, door and frames, partitions,
               etc. in loading dock areas.

          3.   Pressure wash exterior aggregate material walls using process
               and materials recommended by installer once every three months.
               Service Contractor shall wash walls to a height mutually agreed
               upon with Owner.

          4.   Pressure wash garage area flooring as needed, but not less than
               once every three months.

     D.   MISCELLANEOUS

          1.   Report to building management any observed building deficiencies,
               leaking or inoperable faucets, plugged sinks or toilets, broken
               fixtures, inoperable lights or switches, loose baseboards, torn
               carpeting in public areas, etc...

          2.   Keep cleaning equipment and supply storage area in neat and
               clean condition at all times. Keep equipment clean and cleaning
               materials properly stored.

          3.   At the conclusion of all work assignments, lights are to be
               turned off, doors locked and the premises left in a neat
               orderly condition.

          4.   Service Contractor will provide and complete a daily services
               journal outlining any issues which need to be brought to the
               attention of Building Management. Service Contractor shall also
               check the journal daily for Management notice of special duties,
               areas requiring attention and service deficiencies, if
               applicable.

VII. DAY PORTERS

     Contractors shall provide as many Day Porters and/or Matrons as required
     and approved by building management, their duties shall include, but not be
     limited to the following:

     A.   DAILY

     1.   Police elevator cabs at main level; vacuum and spot clean carpeting
          as needed or at least twice per day.

<PAGE>

          2.  Police lavatories keeping them in neat and clean condition.  Wipe
              clean sink, vanity tips and toilet seats.  Mop up water from
              floors as necessary.  Spot clean mirrors.  Check toilet tissue,
              hand towels, soap dispensers, and sanitary supplies and refill as
              necessary or at least twice per day.

          3.  Sweep sidewalks when necessary.  Shovel snow during and
              immediately after snow fall and put down appropriate ice melting
              materials provided by the building as needed.

          4.  Police stairways and keep free from trash and debris as needed.

          5.  Police and keep free from trash and debris areas in main lobby
              and building exterior including sidewalks, curbs and alley as
              needed.  Wet mop lobby flooring as necessary, particularly during
              inclement weather or when snow and ice is prevalent.

          6.  Police entire site in accordance with the City's "Adopt a Street
              Program" as needed.

          7.  Keep main entrance door and entryway glass free from finger
              marks and smudges; clean and polish door frames and other
              decorative metal. All metal is to be cleaned with a clean, soft
              cloth dampened with water only as necessary.

          8.  Keep service corridors, utility areas, dock/receiving and garage
              areas in a clean and neat condition as needed.

          9.  Set out walk-off mats, safety cones and appropriate signage on
              rainy or snow days and keep them in a clean condition as needed.

          10. As directed by building management, sweep and/or wet mop
              equipment rooms, fan rooms, utility rooms, elevator pits, etc. as
              needed.

          11. Render any other services as directed by building management
              daily or as necessary.

     B.   WEEKLY

          1.  Empty money from sanitary machines and deliver to Management
              Office.

     C.   MONTHLY

          1.  Vacant tenant areas shall be kept free from trash and debris
              and completely swept or vacuumed at least twice per month.

Note: The foregoing specifications are intended to be a guide to the duties
of the day personnel. It is understood and agreed by Service Contractor and
Building Management that the Day Porter's duties shall at times be directed
by Building Management's authorized representative.

Assignment of Day Personnel shall be directed by Building Management.


<PAGE>

VIII.     WINDOW WASHING

          A.  Contractor shall clean all first floor interior lobby windows
              twelve (12) times per year.

          B.  Contractor shall clean all first floor exterior lobby windows
              twelve (12) times per year.

          C.  Contractor shall clean all interior windows above the first
              floor two (2) times per year.

          D.  Contractor shall clean all exterior windows above the first
              floor three (3) times per year.

          E.  Contractor shall supply all labor, materials and equipment
              necessary to perform interior and exterior window cleaning.
              Owner shall maintain and provide to the Contractor window washing
              davits for use with the Contractor's window-washing rig.
              Contractor agrees to install and utilize window-washing davits in
              accordance with manufacturer's specifications.

          F.  Contractor agrees to comply with all requirements for any Owner
              equipment in order to ensure safe use and operation of such
              equipment.

          G.  Contractor shall provide all barriers and all other equipment
              and materials necessary to ensure safety during interior and
              exterior window cleaning.

          H.  Contractor agrees to comply with all requirements for any Owner
              equipment in order to ensure safe use and operation of such
              equipment.

          I.  Contractor shall notify Owner of any problems as it relates to
              equipment owned and maintained by Owner.

          J.  Contractor shall perform interior window cleaning above the
              first floor between 6:00 p.m. and 6:00 a.m., Monday through
              Friday.

          K.  Contractor shall perform exterior window cleaning above the
              first floor between  6:00 p.m. and 6:00 a.m., Monday through
              Friday.

          L.  Contractor shall perform first floor lobby window interior and
              exterior cleanings between 7:00 p.m. and 6:00 a.m., Monday
              through Friday or any time Saturday and Sunday.

          M.  All exterior and interior window cleaning scheduling shall be
              coordinated and approved by Owner prior to any window cleaning.

          N.  Contractor shall clean all metal mullions and frames during
              regular window cleaning at no additional cost.

          O.  Contractor shall remove from the property or store it's window
              rig in Owner designated area directly after each scheduled
              exterior window cleaning.  The


<PAGE>

              window-washing rig must be stored and shall not be visible from
              the exterior of the building after each day of service.

          P.  Contractor shall maintain and supply to Owner a daily service
              logbook recording all cleaning activity, related activity and
              equipment malfunctions.

          Q.  Contractor shall maintain minimum insurance coverage as
              required by Owner.


IX.       MISCELLANEOUS

          A.  Service Contractor shall pad vacuums, carts and other equipment
              to prevent scratches and other damage in furniture, door frames,
              etc.  Cleaning personnel shall be instructed not to pull cords
              around corners.

          B.  Report to Building Management any use of electrical/telephone
              closets for storage.

          C.  Report to Building Management any observed building
              deficiencies, e.g., leaking or inoperable faucets, plugged sinks
              or toilets, broken fixtures, inoperable lights or switches, loose
              baseboards, faulty locks, burnt out light bulbs, etc.

          D.  At the conclusion of all work assignments, lights are to be
              turned off, doors closed and locked, chairs centered and gently
              pushed under tables or desks so as not to scratch furniture, and
              premises left in neat and orderly condition.

          E.  Return all keys, cardkeys, radios and any other building
              equipment signed out that day.

          F.  Service Contractor's cleaning personnel will be required to
              pass out gifts and notices to buildings tenants from time to time;
              i.e., holiday gifts, window cleaning notices, tenant survey, etc.

          G.  All Service Contractor's equipment shall be clean and free of
              dirt, shall not have stickers or other idenification and shall be
              in good working order.

          H.  All Service Contractor's personnel are subject to nightly
              inspection; cannot remove items from the building without prior
              supervisory approval.

          I.  No personal articles in slop sinks or storage areas at any time.

          J.  Service Contractor will supply all cleaning supplies and
              equipment necessary at their solo cost.


<PAGE>

                                   EHXIBIT E

               COMMENCEMENT DATE AND EXPIRATION DATE CONFIRMATION


LANDLORD:          Union Tower Investors II, L.L.C.,
                   a Delaware limited partnership

TENANT:            Participate.com, Inc.,
                   a Delaware corporation

BUILDING:          Union Tower, Chicago, Illinois

LEASE DATE:        February 9, 1999

Landlord and Tenant acknowledge and agree that the Commencement Date of the
Lease is _________________, 2000 and the Expiration Date is ___________, 2010.
The parties acknowledge that the Expiration Date is subject to change in the
event that Tenant exercises the Expansion Option (as defined in Article 41 of
the Lease).

LANDLORD:               UNION TOWER INVESTORS II, L.L.C.,
                        a Delaware limited liability company

                        By:  Walton Street Real Estate Fund II, L.P.,
                             a Delaware limited partnership, its
                             managing member

                             By:  Walton Street Managers II, L.P.,
                                  a Delaware limited partnership,
                                  its general partner

                                  By:  WSC Managers II, Inc.,
                                       a Delaware corporation,
                                       its general partner

                                       By:
                                          --------------------------------
                                       Name:
                                            ------------------------------
                                       Title:
                                             -----------------------------

TENANT:                 PARTICIPATE.COM, INC.,
                        a Delaware corporation

                        By:
                           --------------------------------
                        Name:
                             ------------------------------
                        Title:
                              -----------------------------


                           Exhibit E