OFFICE LEASE

Exhibit 10.1

OFFICE LEASE

by and between

10 – 30 SOUTH WACKER, L.P.

(“ Landlord ”)

and

CHICAGO MERCANTILE EXCHANGE INC.

(“ Tenant ”)

Dated as of August 24, 2007

TABLE OF CONTENTS

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EXHIBITS

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INDEX OF DEFINED TERMS

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LEASE

Landlord and Tenant enter this Lease (“ Lease ”) as of the Execution Date on the following terms, covenants, conditions and provisions:

1.1. Basic Lease Definitions. In this Lease, the following defined terms have the meanings indicated.

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2.1. Project . “ Project ” means, collectively, the Land, the Building (including the parking garage in the Building (the “ Parking Facilities ”) and the Common Areas), and all plazas, sidewalks, and curbs adjacent thereto.

2.2. Land . “ Land ” means the real property (including air rights) more particularly described on Exhibits A-1 , A-2 , and A-3 , including easements and other rights that benefit or encumber such real property.

2.3. Base Building . “ Base Building ” means the Building Structure and the Mechanical Systems, collectively, defined as follows:

(a) Building Structure . “ Building Structure ” means the structural components in the Building, including foundations, floor and ceiling slabs, roofs, exterior walls, exterior glass and mullions, columns, beams, shafts, and emergency stairwells. The Building Structure excludes the Leasehold Improvements (and the leasehold improvements to other tenant premises in the Building, whether or not occupied or leased) and the Mechanical Systems.

(b) Mechanical Systems . “ Mechanical Systems ” means the base building systems generally serving the Building, including the sprinkler, plumbing, HVAC, electrical, metering, lighting, communications, security, drainage, sewage, waste disposal, vertical transportation (other than the Exclusive Freight Elevator), and fire/life safety systems, in each case up to the point of distribution of such system in the Premises and other leasable areas of the Building. “ Mechanical Systems ” shall also include (i) the black iron ductwork serving the kitchen spaces which exist on the Execution Date in the Premises, and (ii) the VAV boxes that are part of the HVAC system (including those VAV boxes located in the Premises).

2.4. Common Areas; Access . (a) Tenant and its employees and invitees shall have access to the Premises (including the Fixed Term Support Space) 24 hours per day, 7 days per week. Tenant and its employees and invitees shall have a non-exclusive right to use the Common Areas subject to the terms of this Lease. “ Common Areas ” means those interior and exterior common and public areas on the Land and in the Building designated by Landlord for the non-exclusive use by Tenant in common with Landlord, other tenants and occupants of the Building, and their employees, agents and invitees, but shall in any event include the emergency stairs and stairwells, the lobbies (excluding the Secured Access Space), all passenger and freight elevators (other than the Exclusive Freight Elevator) serving the Premises, and all washrooms, common hallways and elevator lobbies on multi-tenant floors.

(b) Landlord and Tenant acknowledge that, prior to the date that the entrance to Tenant’s visitors center (the “ Visitor’s Center ”) is to be relocated from the 30 South Wacker Building to the 20 South Wacker Building (which relocation date shall be mutually and reasonably agreed upon between Landlord and Tenant, but in no event shall such relocation occur later than June 30, 2008 (the “ Relocation Date ”)), the Secured Access Space is demised in

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such a manner that a freight elevator and a janitor closet on the lower lobby level can only be accessed through the Secured Access Space. Notwithstanding anything to the contrary in this Lease, Landlord and its employees, agents and contractors shall have the right to enter the Secured Access Space at all reasonable times for the purpose of using such freight elevator and janitor closet (excluding periods during which special events are occurring ( provided , that (i) Tenant shall deliver notice to Landlord at least 5 business days prior to such special event and (ii) such access to said freight elevator and janitor closet through the Secured Access space would unreasonably interfere with the special event in question), absent an emergency). However, Tenant may require an employee of Tenant or its security service to accompany Landlord’s personnel (or its agents or contractors) while in the Premises, provided , that Tenant has made such employee available to Landlord when Landlord’s personnel (or Landlord’s agents or contractors) desire to use such freight elevator or janitor closet. From and after the Relocation Date, such freight elevator and janitor closet shall be accessible through the Common Areas, and this Section 2.4(b ) shall be of no further force or effect.

(c) To the extent reasonably required by Tenant, Tenant shall have access to areas within the Building but outside of the Premises in which Landlord has permitted Tenant to install equipment, wiring, piping, conduit, cabling, or ductwork at reasonable times upon reasonable notice to Landlord, and Landlord shall have the right to require, as a condition to such access, that Tenant (or Tenant’s employee, contractor, or other representative) at all times be accompanied by a representative of Landlord (and/or, at Landlord’s discretion, a representative of a third party riser management company retained by Landlord) who Landlord shall make available upon reasonable notice. Notwithstanding the foregoing, but subject to Section 6.4(b) , Tenant shall have such access without accompaniment to the telecommunications closets (and the riser to which they provide access) in the 10 South Wacker Building which are, as of the Execution Date, exclusively for Tenant’s use for Tenant’s telecommunications cabling, conduit, and wiring, and related equipment (“ Tenant Exclusive Telecom Closets ”).

2.5. Premises . On or before January 31, 2008, time being of the essence, Tenant shall elect the Premises which shall be the subject of this Lease from and after December 1, 2008. Tenant shall make such election, electing only Scheme F-1 (as set forth on Exhibit B-1) or Scheme F-2 (as set forth on Exhibit B-2) by giving to Landlord written notice. If Tenant does not timely make such election, then Tenant shall be deemed to have elected Scheme F-1.

(a) Leasehold Improvements . The Premises includes the Leasehold Improvements. “ Leasehold Improvements ” means all improvements in or serving the Premises that are not Building Structure or Mechanical Systems. The Leasehold Improvements may exist in the Premises as of the Execution Date, or be installed by Landlord or Tenant under this Lease at the cost of either party, including, but not limited to Landlord’s Work. The Leasehold Improvements include: (1) interior walls and partitions (including those surrounding structural columns entirely or partly within the Premises); (2) the interior one-half of demising walls; (3) the interior drywall on exterior structural walls; (4) stairways and stairwells, if any, installed by or on behalf of Tenant within the Premises; (5) the frames, casements, doors, windows and openings installed in or on the improvements described in clauses (1)  through (4) , or that provide entry/exit to/from the Premises; (6) all hardware, fixtures, cabinetry, railings, paneling, woodwork and finishes in the Premises or that are installed in or on the improvements described in clauses (1)  through (5) ; (7) the Exclusive Freight Elevator; (8) integrated ceiling systems

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(including grid, panels and lighting); (9) carpeting and other floor finishes; (10) kitchen, rest room, lavatory or other similar facilities that are within and exclusively serve the Premises (including plumbing fixtures, toilets, sinks and built-in appliances); and (11) the distribution of the Mechanical Systems from the common point of distribution for each system to and throughout the Premises. Notwithstanding the foregoing, the Leasehold Improvements shall in no event include any portion of the Building Structure or the Mechanical Systems, whether or not located in the Premises.

(b) Exclusions from the Premises . The Premises shall not include: (1) any areas above the finished ceiling or integrated ceiling systems, or below the finished floor coverings that are not part of the Leasehold Improvements; (2) janitor’s closets (which serve a multi-tenant floor); (3) stairways and stairwells to be used for emergency exiting or as Common Areas; (4) rooms for connection of electrical and/or telecommunication equipment on multi-tenant floors; (5) vertical transportation shafts (or anything therein); (6) vertical shafts, risers, chases, flues or ducts; and (7) any easements or rights to natural light, air or view. Without limiting the foregoing, neither the RSF of the Premises nor the USF of the Secured Access Space shall include (for purposes of calculating Base Rent or Additional Rent) the low-rise elevator lobby of the adjacent corridor space in the 30 South Wacker Building, even though such space may be accessible from the Premises only.

(c) Tenant Access to Certain Facilities . Notwithstanding what is set forth in this Lease, Tenant shall have non-exclusive access to the areas between the ceiling of the Premises and the slab of the next higher floor without Landlord’s prior consent to the extent that Leasehold Improvements, including without limitation telecommunications cabling, are located there. Landlord shall not make any installations in such areas that would materially interfere with any Leasehold Improvements located therein. In addition, Tenant acknowledges that its use of dedicated rooms for connection of electrical and/or telecommunications equipment on full floors of the Premises is non-exclusive (except for Tenant Exclusive Telecom Closets in the 10 South Wacker Building), that Tenant’s installations in such rooms shall not exceed a reasonable portion of the total space available in each such room (provided such reasonable portion shall not be less than the current space allotted Tenant as of the Execution Date), and that Landlord shall have the right to install equipment or permit third-party providers to install equipment, including, without limitation, telecommunications cabling, in the remaining portion of such rooms. Landlord and Tenant shall cooperate to ensure that none of the installations made by (or at the direction of) either of Landlord or Tenant in such rooms shall prevent the use of, or reasonable access to, the installations made in such rooms by (or at the direction of) the other party.

(d) Keys . Tenant shall have the right to make (or have made for it) all locks and keys, key or proximity cards or other access devices for any or all points of entry into the Premises or within the Premises. Tenant shall provide Landlord with a complete set of such keys, key or proximity cards, or other access devices. On or prior to June 1, 2008, Landlord shall cause the Building access and security systems to be made compatible with Tenant’s keycard system so Tenant’s employees may use their Tenant-issued key cards for access to both of the Building and the Premises. Tenant shall reasonably cooperate with Landlord to enable Landlord to comply with the obligation set forth in the foregoing sentence.

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(e) Exclusive Freight Elevator . During the Term, Tenant shall have the exclusive right to use the freight elevator located in the 30 South Wacker Building and identified on Exhibit H (the “ Exclusive Freight Elevator ”), provided that Landlord shall have the right to use the Exclusive Freight Elevator (in cooperation with Tenant’s exclusive use of same), upon notice (which notice may be oral to Tenant’s facility personnel) to Tenant and subject to Tenant’s reasonable approval. Pursuant to the terms and limitations of Sections 9.1(d) , 11.3(b)(1) and 11.3(b)(2) , Landlord shall indemnify and defend and hold Tenant harmless from and against Claims arising from Landlord’s use of the Exclusive Freight Elevator under this Section 2.5(e) . Tenant, at Tenant’s expense, shall operate, maintain, repair, and replace the Exclusive Freight Elevator, which obligation shall include, without limitation, (1) providing any necessary personnel to operate the Exclusive Freight Elevator, (2) entering into a service contract in form and with a vendor reasonably acceptable to Landlord that provides for the regular maintenance the Exclusive Freight Elevator, (3) paying the cost of all of the electric current consumed by the operation of the Exclusive Freight Elevator, and (4) performing any repair, restoration, or replacement required as a result of a casualty affecting the Exclusive Freight Elevator.

2.6. Building Standard . “ Building Standard ” means the general type or quality of materials Landlord reasonably designates for use in the Building from time to time, which shall be of no lesser quality than those materials used in similar first class office buildings in downtown Chicago.

2.7. Tenant’s Personal Property . “ Tenant’s Personal Property ” means Tenant’s trade fixtures, furnishings, equipment, work product, inventory, stock-in-trade and other personal property of Tenant that are not permanently affixed to the Premises.

3.1. Delivery of Premises . The parties acknowledge that as of the Execution Date, Tenant occupies all of the Premises (excluding the area currently used for escalators and other purposes that is part of Landlord’s Work to convert to space which Tenant may occupy for the conduct of Tenant’s business as contemplated herein) pursuant to the Current Leases (as defined in Article 31 ). Therefore, Tenant shall accept possession of the Premises on the Scheduled Commencement Date in its then “as is” condition, subject to the completion of Landlord’s Work in accordance with the provisions of this Lease. Except for Landlord’s Work, Landlord has no obligation to perform any work, supply any materials, incur any expense, or make any alterations or improvements to prepare the Premises for Tenant’s occupancy; provided , that nothing in this sentence shall negate Landlord’s obligations expressly set forth elsewhere in this Lease.

3.2. Term . “ Term ” means the period that begins on the Scheduled Commencement Date and ends on the Expiration Date, subject to renewal or extension as provided in Article 17 or earlier termination as provided in this Lease (including Article 18) or at law. “ Month ” means a full calendar month of the Term.

3.3. Holdover . If Tenant keeps possession of any portion of the Premises after the Expiration Date (or earlier termination of this Lease), without Landlord’s prior written consent (a “ Holdover ”), which may be withheld in Landlord’s sole discretion, then in addition to the

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remedies available elsewhere under this Lease or at law, Tenant shall be a tenant-at-sufferance and must comply with all of Tenant’s obligations under this Lease, except that for each Month of any Holdover, Tenant shall pay 150% for the first 30 days and 200% thereafter of the Rent payable for the last Month of the Term with respect to the entire Premises (or that would have been payable but for abatement or excuse), without proration for any partial Month of Holdover. If Landlord signs a lease with another Tenant for any portion of the Premises subject to a Holdover and gives to Tenant notice of the execution of such lease and of the date Landlord requires the Premises in order to meet the obligations of such lease (“ New Lease Date ”), Tenant shall indemnify and defend and hold Landlord harmless from and against all Claims that Landlord suffers due to the Holdover of such portion of the Premises for more than 30 days after Landlord gives to Tenant such notice or 30 days after the Expiration Date or earlier termination of this Lease, whichever is later. Landlord’s deposit of any of Tenant’s Rent payments during any Holdover will not constitute Landlord’s consent to such Holdover, or create or renew any tenancy.

3.4. Condition on Expiration .

(a) Return of the Premises . At the end of the Term, Tenant will return possession of the Premises to Landlord vacant, free of Tenant’s Personal Property, in broom - clean condition, and with all Leasehold Improvements in good condition and repair, excepting ordinary wear and tear, damage by fire or other casualty or condemnation that is not Tenant’s obligation to restore under Articles 10 or 12 (and excepting normal, minimal damage from removal of trade fixtures). In addition, Tenant shall remove (and restore the Premises damaged by removal of) all of the Required Removal Items. Notwithstanding any provision hereof to the contrary, Tenant shall not be required to remove (1) any of the Leasehold Improvements existing prior to the Execution Date and (2) any other Alterations other than the Required Removal Items. “ Required Removal Items ” means Alterations made after the Execution Date (i) consisting of internal stairwells, floor cuts, floor coring, vaults (other than the electric utility vaults) or structural steel, (ii) that have altered the exterior curtain wall, facade or exterior windows of the Building, including without limitation by the installation of ventilation louvers (which must be removed and the curtain wall restored), (iii) that consist of (A) executive bathrooms, (B) bathrooms, shower rooms, and locker rooms installed to service any fitness center in the Premises, (C) kitchen improvements for commercial food preparation service or cafeteria operations (including commercial-style sinks, disposals, grease traps, built-in refrigeration, hoods and venting, but excluding pantries, lunch and breakout rooms with microwave cooking only or the use of caterers in same with warming facilities that do not require venting and excluding any Alterations within or serving the existing Club area on the upper lobby level space), and (D) UPS or battery back-up systems, or (iv) that Landlord required in writing to be removed (or reserved the right to so require (in which case Tenant shall request Landlord’s final determination with respect to such items by giving to Landlord notice at least 30 but not more than 60 days prior to the Expiration Date (or within 10 days of any earlier termination of this Lease)) at the time of approval of the installation of same or for which Tenant failed to obtain Landlord’s written consent, if required, under Section 8.1(a) . In no event shall the Required Removal Items include any wiring or cabling or any item of Landlord’s Work.

(b) Correction by Landlord . If Tenant fails to return possession of the Premises to Landlord in the condition required under Section 3.4(a) , then Tenant shall reimburse

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Landlord for 110% of the actual and reasonable out of pocket costs incurred by Landlord to restore the Premises to the condition required under Section 3.4(a) .

(c) Abandoned Property . Tenant’s Personal Property left behind in the Premises after the end of the Term (and any period of Holdover pursuant to Section 3.3 ) shall be considered abandoned. Landlord may move, store, retain or dispose of such Personal Property and Tenant shall reimburse Landlord for 110% of the reasonable cost incurred by Landlord in connection therewith.

4.1. Base Rent . (a) Tenant shall pay Base Rent in advance, in equal Monthly installments, commencing (subject to the provisions of Section 4.1(b)) on the Scheduled Commencement Date, and on the first day of each Month thereafter during the Term; provided , that if the first day of a Month is not a business day then Base Rent shall be due on the first business day of such Month. Base Rent for any partial Month shall be prorated.

(b) If Landlord’s Work with respect to any particular floor of the Premises in any of the 10 South Wacker Building, the 20 South Wacker Building, or the 30 South Wacker Building has not been Substantially Completed on or before the date (each, a “ Delivery Deadline ”) that is 75 days (as such 75-day period may be extended by reason of Tenant Delay and/or Force Majeure delay affecting Landlord’s Work on such floor) after the date set forth in Exhibit E for Substantial Completion of such floor, then, as Tenant’s sole and exclusive remedy therefor (except as set forth in Sections 15.9 , 15.10 , 15.11 , and 19 ), the Base Rent (and the Additional Rent under Section 4.2) attributable to such floor shall be abated by (i) one day for each day after the applicable Delivery Deadline that Landlord’s Work with respect to such floor has not been Substantially Completed, for up to 75 days, and (ii) two days for each day from and after the 76th day after the applicable Delivery Deadline that Landlord’s Work with respect to such floor has not been Substantially Completed. For purposes of this Section 4.1(b) , the portion of Landlord’s Work consisting of the replacement of the Building facade on the 20 South Wacker Building shall be deemed to be part of Landlord’s Work applicable to (and only to) the third floor in the 20 South Wacker Building (unless Tenant elects Scheme F-2 pursuant to Section 2.5 , or is otherwise leasing the seventh floor of the 20 South Wacker Building, in which case such work shall also be deemed to be part of Landlord’s Work applicable to the seventh floor in the 20 South Wacker Building). Notwithstanding anything to the contrary contained in this Section 4.1(b) , Tenant shall not be entitled to an abatement of the Base Rent or the Additional Rent under this Section 4.1(b) in respect of any particular floor of the Premises in any particular Building if Tenant has taken possession of such floor (whether for the performance of Tenant’s Work, for the conduct of business or otherwise). “ Tenant Delay ” means any delay that Landlord may encounter in the performance of Landlord’s obligations under this Lease by reason of any act or omission of any nature of Tenant, its agents or contractors, including, without limitation, delays due to changes in or additions to Landlord’s Work requested by Tenant, delays by Tenant in submission of information or giving authorizations or approvals, delays due to the postponement of any of Landlord’s Work at the request of Tenant, or delays due to Tenant’s failure to surrender any space to Landlord in a timely manner and in the Delivery Condition required for Landlord to commence Landlord’s Work in such space (whether such delays are within or outside of the space in question). Tenant shall pay to Landlord any actual incremental

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out-of-pocket costs or expenses incurred by Landlord by reason of any Tenant Delay. “ Substantial Completion ” (and with correlative meaning, “ Substantially Complete ” and “ Substantially Completed ”) of Landlord’s Work means that Landlord’s Work shall have been substantially completed other than minor construction and finishing details that would not materially interfere with the performance of Tenant’s Work or the conduct of Tenant’s business in the space in question. “ Delivery Condition ” means Tenant’s removal, at its sole cost and expense, of any and all furniture, moveable personal property, equipment (including, without limitation, computers) and other moveable items from all offices and other areas of the floor in question (other than such items located in or about the third floor (and if applicable, seventh floor) of the 20 South Wacker Building; it being understood that all such items left by Tenant in or about the Premises may be demolished and/or removed by Landlord as part of Landlord’s Work without any liability to Tenant therefor).

4.2. Additional Rent . Tenant’s obligation to pay Taxes and Expenses under this Section 4.2 is referred to in this Lease as “ Additional Rent ”.

(a) Taxes . For each full or partial calendar year during the Term, Tenant shall pay, in the manner described below, Tenant’s Share of Taxes attributable to each of the 10 South Wacker Building and the combined 20 South Wacker Building and the 30 South Wacker Building, each based upon Tenant’s Share thereof, without double counting. “ Taxes ” means the total costs incurred by Landlord for: (1) real property taxes and assessments (including ad valorem and special assessments) levied on the Project and Landlord’s personal property used in connection with the Project; (2) taxes, if any, on Landlord’s personal property used in the Project (but not the Illinois personal property replacement income tax); (3) taxes, assessments or fees in lieu of the taxes described in clauses (1)  and (2) of this sentence including, without limitation, (A) a tax, assessment, levy, imposition, or charge based on the income or rents received from the Project whether or not wholly or partially as a capital levy or otherwise, (B) a tax, assessment, levy, imposition, or charge measured by or based in whole or in part upon all or any portion of the Project and imposed upon Landlord, (C) a license fee measured by the rents due at the Project, or (D) any other tax, assessment, levy, imposition, charge, or license fee however described or imposed, including business improvement district impositions; and (4) the reasonable costs incurred to reduce the taxes described in clauses (1)  and (2)  of this sentence; less (5) Taxes billed to retail tenants of the Project. The amount of Taxes attributable to any calendar year of the Term shall be in the amount of Taxes accrued for such year (for example, real property taxes for tax year 2008 will be accrued in calendar year 2008 and will be paid in calendar year 2009). In the case of special Taxes or assessments which may be paid by Landlord in installments without incurring interest, only the amount of each required installment accrued for a calendar year shall be included in Taxes. Landlord shall use commercially reasonable efforts to maintain the real estate taxes applicable to the Project at a level consistent with the real estate taxes of other first class office buildings in the downtown Chicago area (including contesting any assessment of the Project for real estate tax purposes if Landlord determines, in Landlord’s sole discretion, that such contest is in the best interest of the Project). If Landlord contests any assessment of the Project for real estate tax purposes, then all costs of such contest shall be included in Taxes. Tenant shall receive a credit against Rent due for Tenant’s Share of any refund of Taxes, net of expenses incurred in connection with obtaining such credit that have not been previously included in Taxes, applicable to the Term. Taxes exclude federal, state and local income taxes and capital stock, franchise, inheritance, transfer, gift or estate taxes and taxes

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paid under Section 4.3 . Taxes shall not include tax penalties incurred as a result of Landlord’s failure to make payments and/or to file any tax or informational returns when due, except that Taxes shall include (i) interest that may accrue during the pendency of any good faith contest of Taxes and (ii) interest and penalties that arise in whole or in part from Tenant’s failure or unwillingness to timely comply with the terms of this Lease (which amounts described in this clause (ii)  shall be reimbursable 100% by Tenant). The benefit of any tax exemption or tax abatement relating to all or any portion of the Project that is attributable to a particular tenant (other than Tenant) shall accrue solely to the benefit of Landlord and Taxes shall be computed without taking into account any such exemption or abatement. If a tax exemption or tax abatement accrues to the benefit of Landlord relating to all or any portion of the Project and is attributable to Tenant, then Tenant shall receive a credit for the amount of such exemption or abatement, but Taxes shall be computed without taking into account such credit. Tenant shall be responsible for any applicable occupancy or rent tax now in effect or hereafter enacted and, if such tax is payable by Landlord, Tenant shall promptly pay such amounts to Landlord, upon Landlord’s demand. Tenant shall be obligated to pay Tenant’s Share of Taxes regardless of whether Tenant may be exempt from the payment of any Taxes as the result of any reduction, abatement, or exemption from Taxes granted or agreed to by any governmental or quasi-governmental entity, or by reason of Tenant’s diplomatic or other tax exempt status.

(b) Expenses . For each full or partial calendar year during the Term, Tenant shall pay, in the manner described below, Tenant’s Share of Expenses attributable to each of the 10 South Wacker Building and the combined 20 South Wacker Building and the 30 South Wacker Building, each based upon Tenant’s Share thereof, without double counting. “ Expenses ” means the total costs (except as set forth in Section 4.2(b)(2) ) incurred by Landlord (determined on an accrual basis) to operate, manage, administer, equip, secure, protect, repair, replace, refurbish, clean, maintain, decorate and inspect the Project, including a market fee to manage the Project of not more than 3% of the gross revenue of the Project, less all Expenses billed to retail tenants in the Project. If either of the 10 South Wacker Building or the combined 20 South Wacker Building and the 30 South Wacker Building is less than 95% occupied and operating, or if Landlord is not furnishing a particular service otherwise includable in Expenses to any tenant of the Building, Expenses attributable to such building(s) which vary with occupancy, or which are not being provided, will be calculated as if such building(s) is (are) 95% occupied and operating and, subject to Article 22 , all such services are provided to all tenants.

(1) Expenses include, without limitation:

(A) Subject to Article 22 and Section 6.3(a) , Standard Services provided under Section 6.1 ;

(B) Repairs and maintenance, including that performed under Section 7.2 ;

(C) Insurance maintained under Section 9.2 (including deductibles to the extent not in excess of those carried by prudent landlords of first class office buildings in downtown Chicago);

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(D) Wages, salaries and benefits of personnel, including an allocable portion thereof for any personnel rendering services to the Project and to other properties of Landlord or Landlord’s Affiliates;

(E) Costs of operating the Project management office (including reasonable rent);

(F) Amortization installments of the following Capital Items in the manner set forth in Section 4.2(c) ;

(i) To comply with insurance requirements or laws enacted, promulgated or amended (to the extent such amendment reasonably requires the Capital Item in question) or which first becomes effective (or the obligation to comply first arises) on or after the Execution Date (“ Mandated Expenses ”);

(ii) That are reasonably calculated, based on reasonable engineering or other applicable studies, to reduce other Expenses or the rate of increase in other Expenses (“ Cost-Saving Expenses ”);

(G) All costs and expenses of any nature incurred by Landlord with respect to the Refrigerated Waste Facility including, without limitation, all costs and expenses of operation, carting, repair, maintenance, betterment, and replacement thereof; and

(H) All costs and expenses of any nature incurred by Landlord with respect to the Parking Facilities (including driveways in and out of same), whether or not of a capital nature, and including all costs and expenses of operation, repair, maintenance, betterment, and replacement thereof; provided , that Landlord deducts from Expenses the revenues associated with the Parking Facilities.

(2) Notwithstanding the foregoing, Expenses exclude:

(A) Taxes;

(B) Interest, principal, points, and fees on debts or amortization on any mortgage or mortgages or any other debt instrument encumbering the Building or otherwise incurred by Landlord (except as expressly permitted in Sections 4.2(b)(1)(F) and 4.2(b)(2)(E) );

(C) Marketing costs including, without limitation, leasing commissions, attorneys’ fees in connection with the negotiation and preparation of letters, deal memos, letters of intent, leases, subleases and/or lease assignments, space planning costs, and other costs and expenses incurred in connection with leases, subleases and/or lease assignment negotiations, and similar transactions with Tenant or present or prospective tenants or other occupants of the Building; and the costs of constructing, operating, or maintaining any leasing office located at the Project (but the ancillary use of a Building management office for leasing purposes shall not disqualify the costs of such management office from inclusion in Expenses);

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(D) Costs billed to or reimbursed by insurance proceeds or tenants of the Building (other than as Additional Rent);

(E) Depreciation, amortization, and interest payments, except as specifically provided herein and except on materials, tools, supplies, and vendor-type equipment purchased by Landlord to enable Landlord to supply services Landlord is obligated to provide under this Lease and otherwise contract for with a third party, and when depreciation or amortization is permitted or required, the item shall be amortized over its reasonably anticipated useful life together with interest at the Amortization Rate; provided , that such depreciation, amortization and interest shall not exceed the amount Landlord would reasonably expect to pay if Landlord contracted on a market-rate basis with a third party for such services;

(F) Costs required to be capitalized (“ Capital Items ”) in accordance with generally accepted accounting principles, consistently applied (“ GAAP ”), except as permitted in Sections 4.2(b)(1)(F) and 4.2(b)(2)(E) ;

(G) Collection costs and legal fees paid in disputes with tenants;

(H) Intentionally Omitted;

(I) Any ground lease rental (other than amounts which constitute a reimbursement to the ground lessor for items which would have been included in Expenses under this Lease if the same were paid directly by Landlord, which amounts may be included by Landlord in Expenses so long as there is no duplication of other amounts included therein);

(J) Rentals for items (except when needed in connection with normal repairs and maintenance of Mechanical Systems or with keeping Mechanical Systems in operation while such repairs are being made) that if purchased, rather than rented, would constitute a Capital Item that is specifically excluded in Section 4.2(b)(2)(F) above (excluding, however, equipment not affixed to the Building which is used in providing janitorial or similar services);

(K) Costs incurred by Landlord for the repair of damage to the Building to the extent that Landlord is or would expect to, if Landlord carried valid and collectible insurance as required by Section 9.2(a) , be reimbursed by insurance proceeds that are in excess of the deductibles carried by prudent landlords of first class office buildings in downtown Chicago, and costs of all capital repairs, replacement or restorations (except those allowed under Section 4.2(b)(1)(F) above), resulting from a casualty regardless of whether covered by insurance;

(L) Costs, including permit, license and inspection costs, incurred with respect to the installation of Tenant or other occupants’ improvements in the Building or incurred in renovating or otherwise improving, decorating, painting, or redecorating vacant space for tenants or other occupants of the Building;

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(M) Expenses in connection with services or other benefits of a type which are not offered to Tenant or for which Tenant is charged directly;

(N) Salaries and benefits, including taxes and insurance, for all employees above the level of General Manager of the Building, and the portion of such salaries and benefits for any employees who render services to the Project and to other properties of Landlord or Landlord’s Affiliates which is allocable to such other properties;

(O) Costs that would not have been incurred by Landlord but for the violation by Landlord or any tenant of the terms and conditions of any lease of space in the Building, and penalties and interest for non-payment or late payment of items otherwise included in Expenses, and costs that would not have been incurred by Landlord but for the violation by Landlord (or its agents or contractors) of any contract, judgment or law;

(P) Overhead and profit increment paid to Landlord or to Affiliates of Landlord for goods and/or services in or to the Building to the extent the same exceed the costs of such goods and/or services rendered by unaffiliated third parties on a competitive basis;

(Q) Intentionally Omitted;

(R) Any compensation paid to clerks, attendants, or other persons in commercial concessions operated by Landlord;

(S) Intentionally Omitted;

(T) Advertising and promotional expenditures and costs of signs in or on the Building identifying tenants of the Building or Landlord but excepting (i) any Building newsletter or seasonal/holiday decorations and (ii) any exterior signs identifying the owner of the Building placed in or around the exterior of and the entrances to the Building (including, without limitation, the revolving door decals identifying the owner of the Building and any lettering or signs identifying the address of the Building);

(U) The cost of any electric power used by any tenant in the Building in excess of the Building standard amount, or electric power costs for which any tenant directly contracts with the local public service company or of which any tenant is separately metered or submetered and is billed by Landlord directly;

(V) Intentionally Omitted;

(W) Tax penalties incurred as a result of Landlord’s failure to make payments and/or to file any tax or informational returns when due;

(X) Costs arising from the gross negligence and/or willful misconduct of Landlord;

(Y) Landlord’s charitable or political contributions;

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(Z) Intentionally Omitted;

(AA) Costs of acquisition of sculpture, paintings or other objects of fine art;

(BB) Costs associated with the operation of the business of the entity which constitutes Landlord as distinguished from the costs of operation of the Building; for example, costs of entity accounting and legal matters, costs of prosecuting or defending any claims or lawsuits by or against any mortgagee or ground lessor, or costs of selling, syndicating, financing, mortgaging or hypothecating any of Landlord’s interest in the Building, costs of any disputes between Landlord and its employees, costs of any disputes between Landlord and Building management or any owner of Landlord, or outside fees paid in connection with disputes between Landlord and other tenants;

(CC) Costs of any “tap fees” or any sewer or water connection fees, in each case solely for the benefit of any particular tenant in the Building;

(DD) Costs incurred in connection with any environmental cleanup, response action, or remediation on, in, under, or about the Premises or the Building (i) to the extent resulting from the actions of Landlord or another tenant or (ii) that arise from the presence of Hazardous Materials in or about the Premises or the Building, (including, without limitation, Hazardous Materials in the ground water or soil) prior to the Execution Date, including, without limitation, costs and expenses associated with the defense, administration, settlement, monitoring, or management thereof; provided , that (1) there shall be included in Expenses any such costs with respect to Hazardous Materials which are cleaning supplies, maintenance supplies, or similar supplies used in compliance with all laws in the ordinary course of operating and maintaining the Building and customarily used at other first class downtown Chicago office buildings, and (2) Tenant shall reimburse Landlord for 100% of any such costs resulting from the acts or omissions of Tenant or anyone claiming under or through Tenant;

(EE) Any entertainment, dining, or travel expenses for any purpose including, but not limited to, tickets for sporting and theater events;

(FF) Any flowers (other than flowers to decorate the Building lobby), gifts, balloons, etc. provided to any entity whatsoever including, but not limited to, Tenant, other tenants, employees, vendors, contractors, prospective tenants and agents, and concierge services;

(GG) Any “validated” parking for any entity;

(HH) Any “finders fees” or brokerage commissions;

(II) Any “above-standard” cleaning or trash collection, removal, hauling, and dumping including, but not limited to, construction cleanup or special cleanings associated with parties/events and specific tenant requirements, in excess of services offered to Tenant;

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(JJ) The cost of any magazine, newspaper, trade periodical, or other similar subscriptions;

(KK) Intentionally Omitted;

(LL) The cost of any “tenant relations” parties, events, or promotions not consented to by an authorized representative of Tenant in writing;

(MM) Reserves for bad debts or other non-cash reserves or reserves deposited with any mortgage lender;

(NN) Costs of installing, operating, and maintaining any specialty improvement including, but not limited to, a cafeteria or dining facility, an athletic or recreational club, an observatory, or a broadcast facility;

(OO) Cleaning/janitorial expenses (other than to Common Areas) if Tenant exercises its rights under Article 22 ;

(PP) Insurance for leasehold improvements of any tenants or occupants of the Project (other than that portion of Landlord’s general insurance for the Project that incidentally covers the replacement of certain leasehold improvements of tenants or occupants of the Project); and

(QQ) If Landlord does not elect to include in Expenses the revenues associated with the Parking Facility, all costs and expenses of any nature incurred by Landlord principally in connection with the Parking Facilities (including driveways in and out of same), whether or not of a capital nature, and including all costs and expenses of operation, repair, maintenance, betterment, and replacement thereof.

(c) Amortization and Accounting Principles.

(1) Each item of Mandated Expenses will be fully amortized in equal annual installments, with interest on the principal balance at the Amortization Rate, over the number of years that Landlord reasonably projects the item of Mandated Expenses will be productive for its intended use, without replacement, but properly repaired and maintained.

(2) Each item of Cost-Saving Expenses will be charged to Expenses over the period Landlord reasonably estimates that it will take for the savings in Expenses achieved by such items to equal their cost together with interest on the unamortized cost thereof at the Amortization Rate. Each year, Landlord may charge to Expenses its reasonable estimate of the savings realized for such year, plus interest on the unamortized balance at the Amortization Rate, until such time as the unamortized balance equals zero. In no event shall the amount included in Expenses in any year for such Cost-Saving Expenses (excluding interest) exceed the reasonably estimated annual savings for such year from the installation of the related Capital Item.

(3) Any item of Expenses of significant cost that is not required to be capitalized but is unexpected or does not typically recur may, in Landlord’s discretion, be

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amortized in equal annual installments, with interest on the principal balance at the Amortization Rate, over a number of years determined by Landlord.

(4) “ Amortization Rate ” means the Prime Rate, or, if Landlord shall have actually obtained financing for such alterations, repairs, replacements, and/or improvements, the actual interest rate incurred by Landlord in connection with such financing. “ Prime Rate ” means the then current rate of interest as announced from time to time by Citibank N.A., or its successor (or a comparable financial institution selected by Landlord) as its prime rate.

(5) In determining Expenses, Landlord shall use accounting principles consistent with those customarily utilized to determine Expenses in other first class office buildings in downtown Chicago, which accounting principles shall be consistently applied from year to year.

(6) Intentionally Omitted.

(7) If, on or before the later of (A) the last day of the calendar year next succeeding the calendar year to which any statement of the actual Additional Rent pursuant to Section 4.2(e) applies and (B) the 270th day after the date Landlord shall have given to Tenant such statement, Landlord discovers an error in the calculation of Expenses for such calendar year that would result in a reduction of Tenant’s Share of Expenses for such calendar year, Landlord shall recalculate Tenant’s Share of Expenses for such calendar year and treat any overpayment by Tenant as an overpayment of Estimated Additional Rent as to which Tenant shall be entitled to a credit.

(d) Estimates . Landlord shall reasonably estimate Additional Rent each calendar year that Additional Rent may be payable. Such estimate may not exceed 105% of the actual Additional Rent for the previous year unless Landlord can reasonably demonstrate the necessity for such additional increase in such estimate. Notwithstanding the foregoing limit on the increase of such estimate, such limit is not a limit or a “cap” on the actual amount of Expenses that Tenant may owe under this Lease for any calendar year. Tenant shall pay the estimated Additional Rent in advance, in equal monthly installments together with Base Rent. Landlord may reasonably revise Landlord’s estimate of Additional Rent (based upon evidence of actual increases in Expenses beyond those originally estimated) not more than once during any calendar year, and Tenant shall pay the monthly installments of such revised estimated Additional Rent, commencing on the first day of the month that is at least 30 days after the date Landlord gives to Tenant notice of such revision. Such revised monthly installments of estimated Additional Rent shall include an adjustment factor to compensate for any underpayment of revised estimated Additional Rent for the calendar year prior to the revision. The aggregate estimates of Additional Rent payable by Tenant in a calendar year is the “ Estimated Additional Rent ”.

(e) Settlement . As soon as practicable after the end of each calendar year that Additional Rent is payable (or, in the case of Taxes, as soon as practicable after receipt of the bill therefor), Landlord shall deliver to Tenant a statement of the actual Additional Rent for such calendar year. The statement of actual Additional Rent shall be binding and conclusive upon

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Landlord and Tenant except for any corrections to the statement made by Landlord on or before the later of (1) the last day of the calendar year next succeeding the calendar year to which such statement relates and (2) the 270th day after the date Landlord shall have given to Tenant such statement, and except for items that are Objections or for which Tenant exercises its Audit Right; provided , that Tenant’s exercise of its Objections and/or Audit Right will not relieve Tenant from its obligation to pay all such actual Additional Rent pending resolution of any Objection or any Audit. If the actual Additional Rent exceeds the Estimated Additional Rent for such calendar year, Tenant shall pay the difference to Landlord in a lump sum as Rent within 30 days after receipt of Landlord’s statement of actual Additional Rent. If the Estimated Additional Rent paid by Tenant exceeds the actual Additional Rent for such calendar year, then Landlord shall credit the amount of the overpayment against Rent next due. Landlord’s and Tenant’s obligations under this Section 4.2(e) shall survive the expiration or earlier termination of this Lease.

(f) Objections . Tenant shall have the right, upon giving to Landlord written notice not later than 120 days after Tenant’s receipt of Landlord’s statement pursuant to Section 4.2(e) (or any correction to said statement pursuant to Section 4.2(e)) , to reasonably and in good faith object to or to question items of Additional Rent (“ Objection ”); provided , that such notice identifies the items objected to or questioned with reasonable specificity. Landlord shall use commercially reasonable efforts to provide a sufficiently detailed explanation to adequately address Tenant’s Objection, but Landlord shall not be required to allow Tenant to conduct an Audit or to provide such detailed information as is normally included in connection with an Audit unless Tenant has exercised its Audit Right.

(g) Secured Access, Support and Storage Space . In no event shall any Additional Rent under this Section 4.2 be due with respect to the Secured Access Space or the Fixed Term Support Space, whether during the initial Term or during any extension thereof pursuant to Article 17 .

(h) No Reduction of Base Rent . In no event shall any decrease in Expenses or Taxes result in a reduction in the Base Rent payable under this Lease; provided , that the foregoing shall not be construed to diminish any right expressly set forth in this Lease that Tenant may have to an offset or credit against Rent.

(i) Allocation of Expenses and Taxes among the Buildings . Landlord shall separately determine Expenses and Taxes for the 10 South Wacker Building and for the combined 20 South Wacker Building and the 30 South Wacker Building. If any Taxes or Expenses are imposed or incurred with respect to both the 10 South Wacker Building and the other Buildings (including the cost of a shared management office), Landlord shall allocate the same in accordance with sound accounting and management practices consistently applied.

4.3. Other Taxes . Upon demand, Tenant shall reimburse Landlord for taxes Landlord may be required to pay (a) on Tenant’s Personal Property (excluding the existing Illinois personal property replacement tax, which is in the nature of an income tax), or (b) which are enacted after the Execution Date in lieu of real estate taxes and payable with respect to (1) Rent, (2) Tenant’s occupancy of the Premises, or (3) this Lease. If Tenant cannot lawfully reimburse Landlord for these taxes, then the Base Rent will be increased to yield to Landlord the same amount after these taxes were imposed as Landlord would have received before these taxes were imposed.

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4.4. Terms of Payment . “ Rent ” means all amounts payable by Tenant under this Lease and the Exhibits attached hereto, including Base Rent and Additional Rent. If a time for payment of an item of Rent is not specified in this Lease, then Tenant shall pay such item of Rent within 45 days after receipt of Landlord’s statement or invoice therefor. Unless otherwise provided in this Lease, Tenant shall pay Rent without notice, demand, deduction, abatement or setoff, in lawful U.S. currency, by wire transfer of funds into any lockbox account or accounts as designated by Landlord. Landlord shall provide the information for such lockbox account(s) pursuant to instructions separate from this Lease. Landlord shall send invoices payable by Tenant to Tenant’s Billing Address; however, neither Landlord’s failure to send an invoice nor Tenant’s failure to receive an invoice for Base Rent (and installments of Estimated Additional Rent) will relieve Tenant of its obligation to timely pay Base Rent (and installments of Estimated Additional Rent). Each partial payment by Tenant shall be deemed a payment on account. No endorsement or statement on any check or any accompanying letter shall constitute an accord and satisfaction, affect Landlord’s right to collect the full amount due, or require Landlord to apply any payment in any particular manner other than to any item of outstanding Rent (or other obligation due from Tenant to Landlord pursuant to this Lease). No payment by Tenant to Landlord will be deemed to extend the Term or render any notice, pending suit or judgment ineffective. Upon 10 business days notice given to the other, each of Landlord and Tenant may change its Billing Address. Any payment made by Tenant to a lockbox maintained by Landlord for the collection of Rent payments shall not be deemed to have been accepted by Landlord if such payment is returned to Tenant within 10 days after Tenant gives to Landlord notice that such payment has been received into such lockbox.

4.5. Financial Statement . If at any time during the Term (as the same may be extended), Tenant’s financial statements are not publicly available to Landlord, then not more than once during each calendar year during the Term (as the same may be extended), Landlord may request from Tenant, and Tenant shall provide to Landlord within 10 business days of such request, Tenant’s financial statement covering the most recent calendar or fiscal year for which such statements are available, certified by a member of Tenant’s senior financial management team to have been prepared in accordance with GAAP (if a GAAP statement is available) except as noted in such certification and without footnotes.

4.6. Audit Right . Landlord shall maintain complete books and records of all Expenses and Taxes (including reasonable back-up documentation) sufficient for the conduct of an Audit. Each calendar year that Additional Rent is payable by Tenant, Tenant may audit Landlord’s calculation of Additional Rent for the previous calendar year only on the following terms and conditions (“ Audit Right ”):

(a) Procedure for Review .

(1) To exercise the Audit Right for any calendar year, Tenant must notify Landlord in writing of Tenant’s election to audit (“ Audit Notice ”) within the later of (A) 120 days after the date Tenant received the annual statement of actual Additional Rent

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relating to such calendar year pursuant to Section 4.2(e) and (B) 30 days after Tenant received Landlord’s explanation of all Objections pursuant to Section 4.2(f) .

(2) The audit shall be limited to those accounting records of Landlord that are directly relevant and reasonably required to determine the Expenses and Taxes for the calendar year that is the subject of the applicable annual statement of actual Additional Rent only.

(3) The audit shall be conducted at the Project or at Landlord’s corporate offices located in the Chicago or New York metropolitan area and shall commence at a time mutually convenient to Landlord and Tenant that is within 30 days after Tenant delivers the Audit Notice to Landlord. The Audit Right shall expire on the date which is 60 days after Tenant or Tenant’s Auditor is provided with all reasonably requested information necessary to complete the audit. Tenant or Tenant’s Auditor may copy any of Landlord’s books or records reasonably necessary for the efficient conduct of such audit or the preservation of records, or reasonably useful in the preparation of (and intended to be included with) the audit report.

(4) Tenant may perform the audit with Tenant’s own employees, or may engage (A) a national public accounting firm, (B) a regional public accounting firm that is reasonably acceptable to Landlord (with the understanding that, as of the Execution Date, BDO Seidman and Blackman Kallick are acceptable to Landlord), or (C) another lease auditor that is acceptable to Landlord in its sole discretion, to perform the audit (“ Tenant’s Auditor ”). In addition, Tenant may submit a list of prospective Tenant Auditors to Landlord for Landlord’s approval hereunder. If Tenant commences an audit with its own employees, Tenant shall have the right to thereafter engage an outside Tenant’s Auditor, and such Tenant’s Auditor shall have the right to commence and complete the audit within a reasonable time not to exceed 30 days after such Tenant’s Auditor commenced its work or the outside date set forth in Section 4.6(a)(3) , whichever is later. In no event shall Tenant engage Tenant’s Auditor on a contingency fee basis or any other fee basis by which the compensation of Tenant’s Auditor is based upon the amount credited by Landlord to Tenant as a result of such audit.

(5) Before commencing any review of Landlord’s books and records, Tenant and Tenant’s Auditor must each agree in writing to keep confidential and not to disclose to any other person or entity Landlord’s books and records that are the subject of review and any negotiation and settlement of any dispute that may arise from the audit; provided , that Tenant may disclose the information Tenant is required to keep confidential to the extent reasonably required (A) by law or governmental regulation, (B) in a court proceeding or arbitration to resolve any dispute arising out of the audit, or (C) to Tenant’s attorneys, accountants and other professionals related to the performance of the audit or resolution of any dispute arising out of the Audit who agree in writing to be bound by Tenant’s confidentiality agreement.

(6) To make a claim for refund of any overpayment of Additional Rent disclosed by the audit, Tenant must notify Landlord in writing of the claim ( “Audit Claim ”) within 30 days after completion of Tenant’s Auditor’s review under Section 4.6(a)(3) or (4) , as applicable. The Audit Claim shall state in reasonable detail the basis for, and calculation of the claim, and shall include a copy of any written audit or report furnished to Tenant.

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(7) Tenant’s failure to timely give Landlord the Audit Notice or Audit Claim, or to otherwise adhere to the procedures set forth above shall constitute:

(A) A waiver of Tenant’s right to audit or otherwise dispute Landlord’s calculation of Additional Rent for the applicable calendar year, including any action that Tenant may be entitled to pursue under law; and

(B) A full release of Landlord for any claim by Tenant of overpayment of Additional Rent for the applicable calendar year.

(8) No subtenant may conduct an Audit. No assignee of Tenant’s rights under this Lease (except a Permitted Transferee) may conduct an audit of Additional Rent for any portion of the Term occurring prior to the effective date of the applicable assignment.

(b) No Default . No Audit Notice or Audit Claim will be effective if, when given or made, a Material Non-monetary Default of this Lease (as defined in Section 16.18 ) has occurred and is then continuing or a monetary Default under Section 15.1 (a)  has occurred and is then continuing.

(c) Resolution of Claim . Landlord and Tenant shall, for a period consisting of not less than 90 days after Tenant delivers to Landlord an Audit Claim (or an Objection, which is not of the type which requires an audit to resolve), attempt in good faith to resolve such Audit Claim.

(d) Costs . Landlord shall reimburse Tenant for Tenant’s reasonable out-of- pocket third-party expenses incurred in connection with an audit if the total Expenses or Taxes used by Landlord to compute Additional Rent for the calendar year audited were overstated by more than 5%; provided , that such costs shall not include the cost of services performed by Tenant’s own employees; and provided further , that Landlord shall not be required to pay any fee that is calculated on a contingency basis, nor shall Landlord be obligated to pay any fee to an auditor to the extent said fee is based upon the amount credited by Landlord to Tenant as a result of such audit. If such total Expenses or Taxes were not overstated, then Tenant shall reimburse Landlord, as Rent, for Landlord’s reasonable out-of-pocket third-party expenses incurred in connection with such audit.

(e) Arbitration . If Landlord and Tenant are unable to resolve the Audit Claim (or the Objection described in Section 4.6(c)) (in whole or in part), then, not more than 30 days after expiration of the 90-day period set forth in Section 4.6(c) , either of Landlord or Tenant may give to the other notice of such party’s election to arbitrate those issues raised by the Audit Claim that remain in dispute, as follows:

(1) Landlord and Tenant shall attempt to agree upon a single arbitrator who shall be a certified public accountant in a national or regional public accounting firm who shall have been active over the 15-year period immediately prior to the date of such appointment in the accounting and/or auditing of first-class commercial high-rise office properties in the county in which the Building is located, and who does not then represent or act and has not represented or acted in the 3 years immediately prior to the date of such appointment on behalf of either of Landlord or Tenant and is not a tenant, subtenant or occupant of the Building or any

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other building in the metropolitan area where the Building is located that is owned or managed by Landlord (a “ Qualified Audit Arbitrator ”). If Landlord and Tenant cannot agree to a single Qualified Audit Arbitrator within 10 business days after either Landlord or Tenant (as applicable) gives to the other the notice to arbitrate pursuant to Section 4.6(e) , then Landlord and Tenant shall each appoint one Qualified Audit Arbitrator within 15 business days after either Landlord or Tenant (as applicable) gives to the other such notice to arbitrate. If either of Landlord or Tenant fails to timely appoint a Qualified Audit Arbitrator, then the Qualified Audit Arbitrator shall be the sole appointed Qualified Audit Arbitrator. If both Landlord and Tenant fail to timely appoint a Qualified Audit Arbitrator then the Audit Claim (or the Objection, as applicable) shall be void and of no further force or effect;

(2) If each of Landlord and Tenant appoints a Qualified Audit Arbitrator, then such two Qualified Audit Arbitrators shall, within 10 days after the later date of appointment of such two Qualified Audit Arbitrators, appoint a third Qualified Audit Arbitrator. If the two Qualified Audit Arbitrators fail to agree upon and appoint a third Qualified Audit Arbitrator, then the identity of the third Qualified Audit Arbitrator shall be submitted to arbitration under the provisions of the commercial rules of the American Arbitration Association, but subject to such arbitrator being a Qualified Audit Arbitrator;

(3) A majority of the three Qualified Audit Arbitrators (or the single Qualified Audit Arbitrator as set forth in Section 4.6(e)(1) above as the case may be) shall, within 30 days after the later of (A) the appointment of the third Qualified Audit Arbitrator and (B) the conclusion of a hearing, if requested by either Landlord or Tenant, giving each of Landlord and Tenant an opportunity to present its evidence and conclusions with respect to the Audit Claim (or the Objection, as applicable), reach a decision as to each item of the Audit Claim (or the Objection, as applicable) in dispute, and shall notify Landlord and Tenant of such decision, and such decision shall be final and binding upon both Landlord and Tenant;

(4) The losing party, if any, in the arbitration shall pay any fees and expenses of the arbitration and the Qualified Audit Arbitrators. If there is no losing party, then each of Landlord and Tenant shall pay any fees and expenses of its respective Qualified Audit Arbitrator, and 50% of the reasonable fees of the third Qualified Audit Arbitrator; and

(5) Any overpayment or underpayment of Expenses or Taxes determined by the Qualified Audit Arbitrators (or Arbitrator, as applicable) shall be paid as follows. If there was an underpayment then Tenant shall pay to Landlord the amount of such underpayment in a lump sum as Rent within 30 days after Landlord gives to Tenant notice of the decision pursuant to Section 4.6(e)(3) . If there was an overpayment then Landlord shall credit the amount of the overpayment against Rent next due. Landlord’s and Tenant’s obligations under this Section 4.6(e)(5) shall survive the expiration of this Lease.

4.7. Credits and Refunds . With respect to any credit against Rent provided under this Article 4 , if this Lease shall expire or terminate before any such credit shall have been fully applied, or if the amount of such credit shall exceed the aggregate amount of Rent next due and payable for the immediately following month, then Landlord shall, within 30 days after the calculation of such credit, refund to Tenant the unapplied balance of such credit, after deducting any monies then owed and payable by Tenant to Landlord.

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5.1. Use . (a) Subject to the provisions of Section 5.1(b) , Tenant shall use and occupy the Premises only for general administrative non-governmental office use consistent with that of comparable first class office buildings in the downtown Chicago area, and the operation of electronic trading, open outcry trading, clearing operations and operations ancillary thereto (the “ Primary Use ”); and, provided , that the same are ancillary to the use of the Premises for the Primary Use, for the following:

(1) the operation of information technology, data, and computer facilities;

(2) intentionally omitted;

(3) a fitness center for use only by Tenant’s employees and the employees of Tenant’s member firms; provided , that Tenant shall cause such exercise facility to be constructed so that no noise or vibration will emanate from the Premises to other portions of the Building which interferes with Landlord or other tenants of the Building;

(4) kitchens, cafeterias, dining facilities, pantries and vending machines ( provided , that each vending machine, where necessary, shall have a waterproof pan thereunder and be connected to a drain) for the preparation and sale of food and beverages (including a bar for the sale and/or serving of alcoholic beverages) (each, a “ Dining Facility ”) for the use of Tenant’s employees and business invitees; provided , that in the case of each such Dining Facility where cooking will be done (other than any Dining Facility where only microwave cooking will be done) (A) such Dining Facility shall have an exhaust system and all flues, vents, grease traps and ansul systems and other similar items that are reasonably necessary, consistent with the standards of a first-class office building in the downtown Chicago area, (B) all ducts and flues shall be installed within the Premises and shall exit the Building from a location reasonably acceptable to Landlord, (C) Tenant shall clean any grease traps, (D) Tenant shall bag all wet garbage, place such garbage in containers that prevent the escape of odors, and immediately dispose of such wet garbage in the Refrigerated Waste Facility to store pending disposal, and (E) Tenant shall contract with an exterminator (such exterminator to be subject to Landlord’s reasonable approval) to exterminate vermin and rodents on a regular basis as part of a program to keep the Premises free of vermin and rodents by reason of the operation of each such Dining Facility; and provided further , that in the case of each such Dining Facility (whether or not cooking will be done), (a) Tenant shall cause the Dining Facility to be properly ventilated so that no odor will emanate from the Premises to other portions of the Building, and (b) Tenant shall otherwise maintain and operate each Dining Facility consistent with the standards of a Dining Facility maintained by a tenant within its demised premises in a first-class office building in the downtown Chicago area;

(5) duplicating, photographic reproduction and/or offset printing facilities for use in Tenant’s business; provided , that Tenant shall cause all such printing facilities to be constructed so that no noise or vibration will emanate from the Premises to other portions of the Building which interferes with Landlord or any other tenants of the Building;

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(6) so long as Tenant is Chicago Mercantile Exchange Inc. or a Permitted Transferee, the Visitor’s Center; provided , that (A) as of the Relocation Date, the entrance to the Visitor’s Center shall be through the 20 South Wacker Building, and (B) the operation of the Visitor’s Center shall not result in persons unreasonably assembling, congregating, or forming a line outside of the Premises or any Building or otherwise impeding the flow of pedestrian traffic outside of the Premises or any Building; and

(7) other ancillary uses reasonably required by Tenant in connection with the conduct of the Primary Use in the Premises and customarily conducted by tenants (including tenants that conduct trading operations) of first class office buildings in the downtown Chicago area.

Landlord does not represent or warrant that the Project is suitable for the conduct of Tenant’s particular business.

(b) Notwithstanding the provisions of Section 5.1(a) , in no event shall Tenant use or occupy the Premises or any portion of the Project in a manner that: (A) adversely interferes with the operation of the Mechanical Systems or the Building Structure; (B) adversely affects the first class character of the Project; or (C) adversely interferes with or disturbs Landlord or any other tenant of the Building. The provisions of this Section 5.1(b) shall not apply to CME, as the provision of this Lease expressly sets forth the manner in which CME shall use or occupy the Premises or any portion of the Project.

5.2. Compliance with Laws and Directives .

(a) Tenant’s Compliance . Subject to the remaining terms of this Lease, Tenant shall comply at Tenant’s expense with all governing authorities, laws, and reasonable directives of Landlord’s insurers of which Tenant is given written notice from and after the Execution Date (to the extent required to preserve the insurability of the Building or, if non-compliance therewith is the cause based upon a reasonable determination, of an increase in the cost of insurance coverage or in the type of insurance coverage required, Tenant shall pay such increase in cost), concerning:

(1) The Leasehold Improvements and Alterations;

(2) Tenant’s use or occupancy of the Premises, including without limitation compliance with the Americans with Disabilities Act and Illinois laws relating to accessibility, and rules and regulations under the foregoing as in effect from time to time, and the actions of any of Tenant’s contractors working in or about the Premises, but excluding any work that is performed by Landlord;

(3) Any condition in the Building created by Tenant, Tenant’s Affiliates, or their respective employees, agents, contractors, or invitees;

(4) Any chemical wastes, contaminants, pollutants or substances that are hazardous, toxic, infectious, flammable or dangerous, or regulated by any local, state or federal statute, rule, regulation or ordinance for the protection of health or the environment (“ Hazardous Materials ”) that are introduced to the Project, handled or disposed of by Tenant,

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Tenant’s Affiliates, or their respective employees, agents, contractors, or (while in the Premises) invitees. In no event shall Tenant, Tenant’s Affiliates, or their respective employees, agents, contractors, or, while within the Premises, Tenant’s invitees, introduce Hazardous Materials into the Premises, except those which are handled and disposed of, as applicable, in accordance with applicable laws and Section 23.3 .

(b) Landlord’s Compliance . Landlord shall comply with all governing authorities and laws, and all reasonable directives of Landlord’s insurers, concerning the Project (including laws governing Hazardous Materials handled or disposed of by Landlord or its Affiliates or any of their contractors), other than those that are Tenant’s obligation under Section 5.2(a) or any other tenant’s obligation under its lease; provided , that if such failure to comply on the part of another tenant materially and adversely affects the Common Areas or the Premises, Landlord shall use commercially reasonable efforts to correct such failure. Landlord shall be responsible for removing any Hazardous Materials from the Project to the extent the presence thereof is a violation of law, except to the extent such were caused by or were the responsibility of Tenant, its Affiliates, or their agents or contractors. If Landlord permits or requires Tenant not to remove the Generator at the expiration or earlier termination of this Lease, then Landlord shall assume liability for any condition or Hazardous Materials relating to the Generator after the date of the expiration or earlier termination of this Lease, except to the extent caused by Tenant in violation of this Lease prior to the date of expiration or earlier termination of this Lease; provided , that the Generator is surrendered to Landlord upon the date of expiration or earlier termination of this Lease in good repair, normal wear and tear excepted, and in compliance with all laws. The cost of Landlord’s compliance under this Section 5.2(b) shall be included in Expenses, except to the extent provided in Section 4.2(b)(2)(DD) .

5.3. Occupancy . Tenant shall not interfere with Building services or other tenants’ rights to quietly enjoy their respective premises or the Common Areas. Tenant shall not make or continue a nuisance, including any objectionable odor, noise, fire hazard, vibration, or wireless or electromagnetic transmission.

6.1. Standard Services .

(a) Standard Services Defined . “ Standard Services ” means:

(1) Subject to Sections 6.3(a) , heating, ventilation and air-conditioning (“ HVAC ”) to the Premises (other than the third floor (and the seventh floor, if Tenant is leasing same) of the 20 South Wacker Building, and any Fixed Term Support Space to which HVAC is not provided as of the Execution Date) during Business Hours substantially in accordance with the design specifications set forth on Exhibit P ;

(2) Tempered water from the public utility for use in restrooms, showers, and kitchens within the Premises and restrooms in the Common Areas;

(3) Subject to Article 22 , cleaning/janitorial services in accordance with the specifications attached as Exhibit F ;

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(4) Access to the Premises (other than the Secured Access Space) during Business Hours via the passenger elevators and escalators (if applicable) described on Exhibit K ; and at all other times access to the Premises (other than the Secured Access Space) by at least one passenger elevator. Landlord shall furnish freight elevator service via the freight elevators described on Exhibit K on Monday through Friday, from 7:00 a.m. to 5:00 p.m., Saturdays, Sundays, and Holidays excepted, to be used on a first-come, first-served basis in common with Landlord and other tenants of the Building. Such normal freight elevator service, if furnished at other times shall be optional with Landlord and shall never be deemed a continuing obligation of Landlord. Tenant may have access to freight elevator service at such other times; provided , that (1) Tenant shall give to Landlord at least 24 hours advance notice of Tenant’s desire to use such freight elevator service (if, however, Tenant gives to Landlord less than 24 hours advance notice, Landlord shall use reasonable efforts to provide Tenant with freight elevator service as soon as practicable) and (2) Tenant shall pay to Landlord any actual incremental out-of-pocket costs or expenses incurred by Landlord in connection with such use;

(5) Security services in a manner consistent with standards maintained in first class office buildings in the downtown Chicago area, but subject to the following. Attached hereto as Exhibit L are the security measures that Landlord and Tenant shall implement at the Building reasonably promptly (except as otherwise provided to the contrary on Exhibit L ) after the Execution Date. Except as otherwise provided to the contrary on Exhibit L , Landlord may modify such security measures from time to time so long as the modified level of security is not materially less than the level that would be provided if the measures described in Exhibit L were in effect;

(6) Landlord shall provide and maintain a refrigerated waste facility (“ Refrigerated Waste Facility ”) for use by all tenants of the Building to store wet garbage pending disposal; and

(7) Window washing of the exterior windows on the standard Building schedule but not less than 3 times per year.

(b) Standard Services Provided . From and after the Execution Date (other than when Tenant is performing Tenant’s Work or when Tenant is not in occupancy of a floor(s) for the conduct of Tenant’s business, i.e., during Landlord’s Work), Landlord shall provide the Standard Services to Tenant, except as provided in this Article 6 . The cost of the Standard Services shall be included in Expenses (except as provided in Section 4.2(b)(2) . Landlord is not responsible for any inability to provide the Standard Services as a result of any of (1) a concentration of personnel or equipment in the Premises that is in excess of that customarily existing in first class office buildings in downtown Chicago, or (2) Tenant’s use of equipment in the Premises that is not customary office equipment, has special requirements, or generates heat in excess of customary office equipment.

(c) Impermissible REIT Income . For so long as Landlord or any entity directly or indirectly owning an interest in Landlord shall be a REIT, any services required to be provided to Tenant under this Lease that may result in the actual or constructive receipt by Landlord (or any member of Landlord) of impermissible tenant service income as described in Section 856(d)(7) of the Internal Revenue Code of 1986, as amended (the “ Code ”), may be

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performed by an Affiliate of Landlord; provided , that such services are at market rates and do not increase the cost of such services over the cost of such services if such services were provided by Landlord.

6.2. Electricity . Electricity for the Premises shall not be furnished by Landlord but shall be furnished by the electric utility company or other provider serving the Building as determined by Landlord; provided , that at any time during the Term, Tenant shall have the right to select the entity that will provide electric current to the Premises. Landlord shall permit Tenant and the electric utility company or other provider to make use of the Building shafts and risers to bring electric current to the Premises. Tenant shall make all necessary arrangements with the electric utility company or other provider for metering and paying for electric current furnished to Tenant, and Tenant shall pay such electric utility company or other provider for all charges for electric current consumed on the Premises during the Term of this Lease. There shall be no mark up by Landlord on said charges for electric current. Tenant’s electric current use in the Premises shall not exceed the capacity of the Mechanical Systems serving the Premises, as the capacity of such Mechanical Systems may be upgraded from time to time. Tenant acknowledges that, as of the Execution Date, the electric current capacity in the Premises for Building Standard light fixtures and convenience outlets for the operation of customary quantities and types of office equipment, is a connected load not to exceed 9 watts per USF of the Premises (“ Maximum Connected Load ”), and Tenant shall not use electric current in the Premises for such purposes at any time in an amount that exceeds the Maximum Connected Load. Notwithstanding the foregoing, Tenant shall not be required to reduce its use of electric current below the amount set forth above if other tenants in the Building require additional electric current. From and after the Trading Termination Date, Landlord shall be responsible for the cost of electric current measured by the electric meters described on Exhibit N .

6.3. Additional Services . Unless Tenant obtains Landlord’s prior written consent (which consent shall not be unreasonably withheld, but may be conditioned on payment to Landlord of any reasonable amounts deemed necessary by Landlord to reimburse Landlord for Landlord’s incremental costs to provide utilities or services to Tenant in excess of the Standard Services), and except as otherwise provided in this Lease, Tenant shall not use utilities or services in excess of the Standard Services; provided , that Landlord shall provide utilities and services in excess of the Standard Services subject to and in accordance with the following:

(a) HVAC .

(1) Subject to Sections 6.3(a)(2) and (b) , if Tenant requests HVAC service during non-Business Hours to the portions of the Premises served during Business Hours pursuant to Section 6.1(a)(1) , then, upon at least 2 hours prior notice to the Building engineer (which notice may be oral to Landlord’s Building management office), Landlord shall provide such HVAC service and Tenant shall pay, as Rent, Landlord’s scheduled rate per hour for such HVAC service with respect to each building elevator rise, which scheduled rates are set forth on Exhibit P and shall not exceed Landlord’s actual costs of providing such HVAC service (but are subject to change from time to time for necessary labor costs, including fully loaded wages and benefits and necessary overtime for Building engineer(s)), which cost shall be accounted for by Landlord to Tenant in reasonable detail.

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(2) From and after the Execution Date, Tenant shall, at its sole cost and expense, provide HVAC (including, without limitation, all its supplemental air conditioning requirements) to the portion of the Premises located on the third floor (and the seventh floor, if Tenant is leasing same) of the 20 South Wacker Building.

(3) From and after the date which Tenant ceases to conduct open outcry trading operations in the Premises (the “ Trading Termination Date ”), the following shall occur:

(A) The chiller plant located in the mechanical room in the 30 South Wacker Building (the “ 20 South Wacker HVAC System ”) shall have become the property of Landlord upon its acquisition of the Building. Tenant hereby represents and warrants to Landlord that Tenant has no right (except pursuant to this Lease), title, or interest in the 20 South Wacker HVAC System. Within 120 days after the Trading Termination Date, Landlord shall install all the necessary equipment to connect the refrigeration capacity of the 20 South Wacker HVAC System to the HVAC system located in the 30 South Wacker Building (such installation and connection work shall hereinafter be referred to as the “ HVAC Connection Work ”), such that the HVAC Connection Work shall cause the refrigeration capacity of each to cool the chilled water loop of both the 20 South Wacker Building and the 30 South Wacker Building. Tenant shall reimburse Landlord, within 45 days after Landlord delivers to Tenant an invoice therefor after such work is substantially completed, 50% of the capital costs of the HVAC Connection Work (which Tenant reimbursement shall not exceed $300,000, i.e., 50% of an aggregate capital costs of $600,000); and

(B) Landlord shall supply Tenant with chilled water for Tenant’s supplemental air conditioning equipment and systems in place as of the Execution Date (the “ Tenant’s Supplemental HVAC System ”). Prior to the Trading Termination Date, Tenant shall deliver a notice to Landlord specifying the number of tons of chilled water that Tenant will require for the Tenant’s Supplemental HVAC System (such amount not to exceed 1,000 tons of chilled water (if Tenant elects Scheme F-1 pursuant to Section 2.5 ) or 1,200 tons of chilled water (if Tenant elects Scheme F-2 pursuant to Section 2.5 )) (the “ Reserved Tonnage ”). Tenant shall pay, as Additional Rent, for Tenant’s usage of chilled water, an amount equal to $100.00 per ton per annum of connected load of the Reserved Tonnage (and, to the extent applicable, any Tenant’s use of chilled water in excess of the Reserved Tonnage); it being agreed that such amount shall be subject to 3.5% increases on January 1st of each year during the Term, which amount shall be payable within 45 days after Landlord delivers to Tenant a bill therefor; and

(C) Tenant shall relocate Tenant’s chilled water cross connect pipes currently located on the south wall of the 10th floor of the 10 South Wacker Building to the core of the 10th floor of the 10 South Wacker Building, as shown on Exhibit M .

(4) If Tenant desires to discontinue use of Landlord’s chilled water for Tenant’s Supplemental HVAC System or any of its supplemental HVAC requirements, Tenant may install and connect to a new cooling system utilizing an outside source of chilled water or river water (which cooling system may be used, in whole or in part, to cool Tenant’s Generator). Landlord shall reasonably cooperate with Tenant to locate and make available to Tenant at no additional charge riser and other mechanical space for Tenant’s use as reasonably necessary to

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install such new cooling system. Tenant shall pay directly to the applicable utility providers the costs of operating such cooling systems, including the cost of chilled water, electricity, and maintenance. Tenant shall install the heat exchangers and other equipment associated with such new cooling system in a portion of the Fixed Term Support Space located on level P-1 of the 10 South Wacker Building (P1-106) as shown on Exhibit M . Landlord shall provide Tenant with riser space for two pipes each up to 12” in diameter from P1-106 to above the finished ceiling of the 10th floor of 10 South Wacker Building. Tenant shall utilize such relocated chilled water cross connect pipes to connect such new cooling system to the portions of the Premises located in the 20 South Wacker Building and the 30 South Wacker Building. Tenant shall install a connection from such relocated chilled water cross connect pipe to the existing riser located behind Stairwell #2 in the 30 South Wacker Building to service the portion of the Premises located in the 30 South Wacker Building. Tenant shall utilize the four fans located on the sixth floor interstitial area to service the third floor of the 20 South Wacker Building, as well as the four fans located on the second floor interstitial area to service both the second floor interstitial area and the third floor of the 20 South Wacker Building. Landlord shall install variable fan drives to the existing four supply and return fans in the sixth floor interstitial area of the 20 South Wacker Building and rebalance the flows. If Tenant is leasing the seventh floor of the 20 South Wacker Building as contemplated under this Lease (under Scheme F-2), Tenant shall utilize the four fans located on the tenth floor interstitial area to service said seventh floor. Tenant, at Tenant’s expense, shall perform any necessary maintenance or other necessary upgrades to such fans. In addition, Tenant may install additional HVAC equipment and piping (and associated ductwork, conduits, and wiring), including connections through two 16” pipes to utilize river water, all as shown on (and in accordance with) Exhibit M . If Tenant is unable (or determines the same is not economically practical) to obtain chilled water from a purchased system (or river water, as applicable) for any reason, Tenant and Landlord shall review options to provide additional cooling required by Tenant, including the installation by Tenant of a new chiller plant in P1-106 with provisions to connect to river water or the existing base building condenser water system at the 10 South Wacker Building, the 20 South Wacker Building and the 30 South Wacker Building, as shown on Exhibit M .

(5) Landlord and Tenant shall reasonably cooperate with each other in connection with the work and systems described in this Section 6.3(a) . All of Tenant’s work described in this Section 6.3(a) shall be in accordance with this Lease including, without limitation, Article 8 .

(b) Lighting . Tenant, at Tenant’s expense, shall supply all lamps, bulbs, ballasts and starters for the Premises.

(c) Other Utilities and Services . Tenant shall pay, as Rent, the actual cost of utilities or services (other than HVAC and lighting addressed in Section 6.3(a) and (b)) either used by Tenant or provided at Tenant’s request in excess of that provided as part of the Standard Services. Tenant’s excess consumption of Standard Services (or services not included in Standard Services) shall be metered to measure Tenant’s consumption.

(d) Kitchen Exhaust Systems Cleaning . Landlord shall clean and maintain Tenant’s kitchen exhaust systems on a monthly basis, and Tenant shall reimburse Landlord for the actual cost of such cleaning and maintenance; provided , that, with respect to the kitchen

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exhaust system existing on the Execution Date which services both the kitchen in the Premises and certain retail tenants, Tenant shall reimburse Landlord for its proportionate share (such share to be based on the number of users at the time in question) of the cost of such cleaning and maintenance until (1) Tenant delivers to Landlord notice that Tenant is no longer utilizing such kitchen exhaust system and (2) Tenant actually ceases to utilize such kitchen exhaust system.

(e) Services Prior to Tenant’s Occupancy . With respect to each floor of the Premises in each of the 10 South Wacker Building, the 20 South Wacker Building and the 30 South Wacker Building, from and after the date that each such floor is Substantially Completed (but prior to the date that Tenant occupies each such floor for the conduct of Tenant’s business), Landlord shall provide normal freight elevator service ( provided , that Tenant shall pay for any incremental out-of-pocket expenses with respect to cab-roof hoisting and the provision of elevator mechanic operators, as well as loading dock and other security personnel). During such period of time, Landlord shall provide, at Tenant’s expense (payable by Tenant within 45 days after Landlord delivers to Tenant an invoice therefor), refuse removal (including dumpsters), and any other services requested by Tenant or Tenant’s contractor which Landlord agrees to provide.

6.4. Telecommunication Services . Tenant shall contract directly with third party providers of telecommunications services and shall be solely responsible for paying for all telephone, data transmission, video and other telecommunication services (“ Telecommunication Services ”) subject to the following:

(a) Providers . Each Telecommunication Services provider who does not already provide service to the Building shall be subject to Landlord’s approval in its reasonable discretion. Without liability to Tenant, the license of any Telecommunication Services provider servicing the Building may be terminated under the terms of such license, or not renewed upon the expiration of such license. Tenant may continue to use Tenant’s existing Telecommunications Services providers (or their respective successors) as of the Execution Date.

(b) Tenant’s Wiring . Other than that which is currently in place (and replacements thereof) and other than that which is run through the Tenant Exclusive Telecom Closets and the risers associated therewith (and replacements thereof), Landlord may designate reasonably convenient locations for all wires, cables, fibers, equipment, and connections (“ Tenant’s Wiring ”) for Tenant’s Telecommunication Services, and, subject to Section 2.4 , restrict and control access to telephone cabinets and rooms pursuant to the Building’s security procedures. Landlord’s access to such cabinets and rooms on full Tenant floors shall be governed by Section 16.17 . Except as otherwise expressly provided in this Lease, Tenant may not use or access the Base Building, Common Areas or roof for Tenant’s Wiring without Landlord’s prior written consent, which consent shall not be unreasonably withheld.

6.5. Special Circumstances .

(a) Except as expressly set forth herein, without breaching this Lease or creating any liability on the part of Landlord, Landlord may interrupt, limit or discontinue any utility or services Landlord provides under this Article 6 (“ Landlord Provided Services ”) or which are obtained by Tenant under this Article 6 (“ Tenant Provided Services ”) under any of the following circumstances: (1) in an emergency; (2) to comply with laws; (3) to repair and

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maintain the Project; or (4) to modify, renovate or improve the Project; provided , that in the case of interruptions pursuant to clauses (3)  and (4) , Landlord shall coordinate any such interruptions with Tenant so as not to unreasonably disrupt Tenant’s use or occupancy of the Premises.

(b) For purposes of this Lease “ Untenantable ” means that all or any portion of the Premises is not usable or available by reason of damage, Interruption of Landlord Provided Services, or lack of access by normal means (including escalators and elevators) for the normal conduct of business, which shall include the practical inability to use any portion of the Premises by reason of damage, Interruption of Landlord Provided Services, or inaccessibility to any other portion of the Premises, and Tenant does not actually use such portion of the Premises. “ Interruption of Landlord Provided Services ” means (1) any interruption, material limitation or discontinuance of any utility or services expressly provided by Landlord to Tenant under this Article 6 , provided that such interruption, material limitation or discontinuance is not caused by (A) a casualty or condemnation described under Articles 10 or 12 or (B) Tenant, Tenant’s contractors or any of their respective agents or employees; or (2) any interruption, material limitation, or discontinuance of any utility or services not expressly provided by Landlord to Tenant under this Article 6 without regard to the cause thereof (including Force Majeure), but caused by Landlord’s gross negligence or willful misconduct. If an Interruption of Landlord Provided Services occurs and continues for a period in excess of 72 hours after Tenant gives to Landlord notice of such Interruption of Landlord Provided Services from Tenant, and as a result of such Interruption of Landlord Provided Services all or any portion of the Premises is rendered Untenantable, then, commencing upon the expiration of such 72-hour period, (i) if such Interruption of Landlord Provided Services is caused by circumstances that are within Landlord’s reasonable control to remedy, Tenant’s Rent will abate in proportion to the portion of the Premises so rendered Untenantable for so long as such Interruption of Landlord Provided Services continues, or (ii) if such Interruption of Landlord Provided Services is caused by circumstances that are not within Landlord’s reasonable control, then 50% of Tenant’s Rent will abate in proportion to the portion of the Premises so rendered Untenantable for so long as such Interruption of Landlord Provided Services continues.

(c) If an Interruption of Landlord Provided Services occurs and continues for a period in excess of 270 consecutive days after Tenant gives to Landlord notice of such Interruption of Landlord Provided Services, and if such Interruption of Landlord Provided Services renders all or substantially all of the Premises Untenantable and Tenant does not actually use such portion of the Premises or conduct Tenant’s business at the Premises, then commencing upon the expiration of such 270-day period, Tenant shall have the right, upon giving to Landlord written notice within 30 days after the expiration of such 270-day period, to terminate this Lease as of the giving of such notice. Tenant hereby acknowledges that, except as expressly provided in Articles 10 and 12 , Tenant’s sole right to terminate this Lease by reason of an Interruption of Landlord Provided Services is as expressly set forth in this Section 6.5(c) , and Tenant hereby waives any right that Tenant may otherwise have at law or in equity (including, without limitation, any right to claim a constructive eviction) to terminate this Lease based on an Interruption of Landlord Provided Services.

(d) Without limiting Tenant’s rights under Section 6.5(b) and Section 6.5(c) , in no event shall Tenant be entitled to any abatement of Rent or right to terminate this Lease by reason of any failure, interruption, limit, or discontinuance of any Tenant Provided Services

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(unless constituting an Interruption of Landlord Provided Services with respect to utilities as described in Section 6.5(b )), and Tenant hereby waives any right at law or in equity to do so.

(e) Without limiting those reasons for an irregularity or stoppage of services that may be beyond Landlord’s control, any such irregularity or stoppage that is required in order to comply with any laws will be deemed caused by a reason beyond Landlord’s control.

6.6. Landlord shall not voluntarily reduce (a) the amount of electric current available to the Premises as of the Execution Date or (b) the number of physical sources from which electric current is supplied to the Building.

7.1. Tenant’s Repairs . Except as provided in Articles 10 and 12 , during the Term Tenant shall, at Tenant’s cost, repair, maintain and replace, if necessary, the Leasehold Improvements and keep the Premises in good order, condition and repair. Tenant’s work under this Section 7.1 must be performed in compliance with law and in a good and workmanlike manner with materials of at least Building Standard. If any repair that is the obligation of Tenant affects the Base Building, then such repair shall be performed by Landlord at Tenant’s reasonable expense; provided , that if such repair obligation affects a portion of the Base Building that exclusively serves Tenant, then Landlord and Tenant shall cooperate to reasonably determine which of Landlord or Tenant shall perform such repair obligation (but in either case such repair obligation shall be performed at Tenant’s reasonable expense). If Tenant fails to perform any of Tenant’s obligations under this Section 7.1 after Landlord gives to Tenant written notice and a reasonable opportunity to perform such obligations (but in any case Tenant shall commence performance of such obligations within 30 days after Landlord gives to Tenant such notice), then Landlord may perform such obligations and Tenant shall pay, as Rent, to Landlord 110% of the reasonable cost of such performance within 30 days after the date Landlord gives to Tenant an invoice therefor. For purpose of performing such obligations, or to inspect the Premises, Landlord may enter the Premises upon giving to Tenant reasonable prior notice (in cases of actual or suspected emergency, only such prior notice as is practicable, if any, shall be required) without liability to Tenant for any loss or damage incurred as a result of such entry (unless caused by Landlord’s or its agents’ negligence or willful misconduct); provided , that Landlord will take reasonable steps in connection with such entry to minimize any disruption to Tenant’s business or its use of the Premises and Tenant may require an employee of Tenant or its security service, if Tenant makes such employee available, to accompany Landlord’s personnel (or its agents or contractors) while in the Premises; and provided further , that absent an actual or suspected emergency, Tenant may reasonably restrict Landlord’s access to all Secured Areas of the Premises. “ Secured Areas ” shall consist of any areas of the Premises reasonably identified by Tenant as having extraordinary security or confidentiality requirements such that such areas are kept locked or inaccessible to persons unauthorized by Tenant (and trading areas shall not automatically be deemed Secured Areas). Tenant shall notify Landlord of (a) any fire or other casualty in the Premises, (b) any damage to or defect in the Premises, including the fixtures and equipment in the Premises, for the repair of which Tenant believes Landlord is responsible, and (c) any damage to or defect in any parts of or appurtenances to the Mechanical Systems located in or passing through the Premises promptly after Tenant learns of the same.

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7.2. Landlord’s Repairs . Except as provided in Articles 10 and 12 , during the Term Landlord shall repair, maintain and replace, if necessary, all portions of the Project that are not Tenant’s responsibility under Section 7.1 or another tenant’s leasehold improvements, and otherwise maintain the Project in good order and condition according to the standards prevailing for first class office buildings in the downtown Chicago area. Except in the case of an actual or perceived emergency, Landlord shall use commercially reasonable efforts to minimize disrupting the ordinary conduct of Tenant’s business in the Premises in performing Landlord’s duties under this Section 7.2 ; provided , that in no event shall Landlord be required to employ premium or overtime labor. Subject to Sections 15.9 , 15.10 , and 15.11 , Tenant may not repair or maintain the Project on Landlord’s behalf or offset any Rent for any repair or maintenance of the Project that is undertaken by Tenant.

8.1. Alterations by Tenant . “ Alterations ” means any modification, addition or improvement to the Premises or Leasehold Improvements made by Tenant during the Term, including any modification to the Base Building or Common Areas required by law or governing authority as a condition to performing an Alteration, and including any Leasehold Improvements made by Tenant to prepare the Premises for Tenant’s occupancy after Landlord’s performance of Landlord’s Work (the “ Tenant’s Work ”). Alterations shall be made at Tenant’s expense, and shall be subject to the following:

(a) Consent Required . All Alterations, except as specifically set forth below in Section 8.1(e) , require Landlord’s prior written consent. If a Design Problem exists, Landlord may withhold its consent in Landlord’s sole discretion; otherwise, Landlord will not unreasonably withhold its consent. Tenant, at Tenant’s expense, shall (1) submit to Landlord for Landlord’s approval detailed plans and specifications (the “ Plans ”) of each proposed Alteration (other than Decorative Alterations), and with respect to any Alteration affecting any Mechanical Systems, evidence that such Alteration has been designed by, or reviewed and approved by, Landlord’s designated engineer for the affected Mechanical System, (2) obtain all permits, approvals, and certificates required by any governmental or quasi-governmental entity, (3) furnish to Landlord duplicate original policies or certificates of workers’ compensation (covering all persons to be employed by Tenant and Tenant’s contractors and subcontractors in connection with such Alteration, commercial general liability (including property damage coverage), business auto insurance, and Builder’s Risk coverage (as described in Article 9 ) all in such form, with such companies, for such periods and in such amounts as Landlord may reasonably require, naming Landlord, landlord’s agents and contractors and any of their employees, any ground lessor and any mortgagee as additional insureds, and (4) except in connection with Tenant’s Work and, upon Landlord’s request, furnish to Landlord reasonably satisfactory evidence of Tenant’s ability to complete and to fully pay for any Alterations (other than Decorative Alterations) that exceed the cost of $5,000,000, in the aggregate. Unless Tenant obtains Landlord’s prior written consent to the Alterations which constitute Required Removal Items becoming part of the Premises to be tendered to Landlord upon the date of termination of this Lease, Landlord may require Tenant to remove such Required Removal Items and restore the Premises pursuant to Section 3.4 upon the date of termination of this Lease. If Landlord fails to reject or object to an Alteration within 10 days of Landlord’s receipt from Tenant of full and final Plans therefor (including, to the extent required, fully certified, stamped and sealed

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architectural and/or engineering plans), then Tenant may give to Landlord a reminder notice stating in all-capital bold-faced type, “IF LANDLORD FAILS TO OBJECT TO THIS REMINDER NOTICE OF REQUEST FOR CONSENT TO AN ALTERATION WITHIN 5 DAYS THEN LANDLORD SHALL BE DEEMED TO HAVE APPROVED SUCH REQUEST”, and if Landlord shall fail to reject or object to such Alteration within 5 days after Tenant gives such reminder notice to Landlord then Landlord shall be deemed to have approved such Alteration.

(b) Design Problem Defined . “ Design Problem ” means a proposed Alteration which:

(1) Does not comply with laws;

(2) Does not meet or exceed the Building Standard;

(3) Exceeds the capacity (unless part of the Alterations would increase capacity accordingly), adversely affects, is incompatible with, or impairs Landlord’s ability to maintain, operate, alter, modify or improve the Base Building;

(4) Affects the exterior appearance of the Building or Common Areas;

(5) Except for Tenant’s Work or work performed as contemplated in Article 6 , involves floor cuts, floor coring, adding new internal stairways, or the installation of vaults or structural steel;

(6) Violates any insurance regulations or standards for a fire-resistive office building;

(7) Causes a “work of visual art” to become “incorporated in or made part of a building” (as defined in the Visual Artists Rights Act of 1990); or

(8) Locates any Leasehold Improvements, equipment, Tenant’s Wiring or Tenant’s Personal Property outside the Premises, including on the roof of the Building, in Common Areas or in telecommunication or electrical closets, except as specifically permitted by this Lease.

(c) Performance of Alterations . Alterations shall be performed by Tenant in a good and workmanlike manner according to plans and specifications approved by Landlord in accordance with Section 8.1(a) . All Alterations shall comply with law and insurance requirements. All Alterations will be performed by qualified contractors that meet Landlord’s reasonable insurance requirements and are otherwise reasonably approved by Landlord. If Landlord does not respond to Tenant’s request for consent to any firm or contractor for Alterations work within 10 days after Landlord receives Tenant’s request then Tenant shall give to Landlord a reminder notice stating in all-capital bold-faced type, “IF LANDLORD FAILS TO RESPOND TO THIS REMINDER NOTICE OF REQUEST FOR CONSENT TO A FIRM OR CONTRACTOR WITHIN 5 DAYS THEN LANDLORD SHALL BE DEEMED TO HAVE APPROVED SUCH REQUEST”, and if Landlord fails to respond to such reminder notice within such 5 days then Landlord shall be deemed to have approved such request. Once

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Landlord approves a firm or contractor, Tenant need not resubmit such firm or contractor for approval for the same project unless Landlord withdraws such approval by giving to Tenant notice, which withdrawal shall state the reasons therefor. Promptly after completing any Alterations requiring Landlord’s consent hereunder, Tenant shall deliver to Landlord “as-built” Plans for such Alterations prepared on an AutoCAD Computer Assisted Drafting and Design System (or such other system or medium as Landlord may accept) (the “ CAD System ”), using naming conventions issued by the American Institute of Architects in June, 1990 (or such other naming conventions as Landlord may accept) and magnetic computer media of such record drawings and specifications translated into DFX format or another format acceptable to Landlord. Tenant, at Tenant’s expense, shall, as and when required, promptly obtain certificates of partial and final approval of such Alterations required by any governmental or quasi-governmental entity and shall furnish Landlord with copies thereof. Upon completion of such Alterations, Tenant shall provide to Landlord copies of all construction contracts, proof of payment for all labor and materials, a copy of the recorded notice of completion, and final unconditional waivers of lien from all contractors, subcontractors, materialmen, suppliers and others having lien rights with respect to such Alterations, in the form prescribed by Illinois law.

(d) Cost Reimbursement . As to Alterations (excluding Tenant’s Work) requiring Landlord’s consent hereunder, Tenant shall reimburse Landlord for the actual reasonable cost that Landlord incurs to review Tenant’s plans therefor; provided , such cost to Tenant shall in no event exceed $0.25 per USF of planned space (i.e., any portion of the Premises where the proposed Alterations are to be made); and provided further , that if Tenant utilizes Landlord’s engineers for the Building to prepare the Plans for the Alteration in question, Tenant shall not be charged for review of the work of such engineer.

(e) Alterations Without Landlord’s Consent . Notwithstanding anything in this Lease to the contrary, Tenant shall have the right, (1) upon giving written or oral notice to Landlord’s Building management office, but without obtaining Landlord’s consent, to make Decorative Alterations to the Premises or perform low voltage cabling installation or removal ( provided that such installation or removal does not involve a Design Problem, will be performed entirely within the Premises, and does not affect in any material respect the Building Structure or the Mechanical Systems), and (2) upon giving Landlord at least 5 business days prior notice of the proposed Alteration, together with the Plans required pursuant to Section 8.1(a) , and provided that such Alteration does not involve a Design Problem, will be performed entirely within the Premises, and does not affect in any material respect the Building Structure or the Mechanical Systems, then without obtaining Landlord’s consent, to make such Alteration to the Premises. “ Decorative Alterations ” are Alterations that (i) consist of cosmetic changes to the interior of the Premises (such as painting, wall coverings, or floor coverings) that do not affect or alter the Base Building, (ii) do not require a governmental permit of any kind, and (iii) are otherwise performed in accordance with the terms of this Lease.

8.2. Alterations by Landlord . Landlord may modify, renovate or improve the Project as Landlord deems appropriate; provided , that Landlord uses commercially reasonable efforts to minimize disrupting the ordinary conduct of Tenant’s business in the Premises; and provided further , that such modifications, renovations and improvements shall not unreasonably reduce Tenant’s access to the Premises or Tenant’s ability to use the Common Areas or reduce Landlord Provided Services below the levels required to be provided pursuant to Article 6 or reduce any Tenant Provided Service.

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8.3. Liens and Disputes . Tenant shall keep title to the Project free of any liens caused by Tenant, its Affiliates, and their agents and contractors, and shall promptly take whatever action is required to have any such lien either (a) released and removed of record or (b) contested, in either case within 30 days after Landlord gives to Tenant notice thereof. If Tenant elects to contest any such lien, Tenant shall conduct such contest diligently and in good faith and, at Tenant’s expense, obtain title insurance insuring over the notice of lien or the lien from Chicago Title Insurance Company, or another local, reputable title company acceptable to Landlord and Tenant, in favor of Landlord and any mortgagee or ground lessor with an interest in the Project, or, at Tenant’s election, provide Landlord with alternative security satisfactory to Landlord in its sole discretion insuring over any possible loss or expense which may arise from non-discharge of such lien. Tenant shall, promptly after the final determination of such contest, pay or discharge any decision or judgment rendered, together with all costs, charges, interest and penalties incurred or imposed or assessed in connection with such contest. Tenant shall indemnify Landlord from and against any and all Claims, costs, and expenses that Landlord reasonably incurs as a result of Tenant’s violation of this Section 8.3 .

8.4. Labor Relations . Tenant shall not employ, or permit the employment of, any contractor, mechanic, or laborer, or permit any materials to be delivered to or used in the Project, if, in Landlord’s sole judgment, such employment, delivery or use will interfere or cause any conflict with other contractors, mechanics or laborers engaged in the construction, maintenance or operation of the Project by Landlord, Tenant or others. If such interference or conflict occurs, upon Landlord’s request, Tenant shall cause all contractors, mechanics or laborers causing such interference or conflict to leave the Project immediately.

8.5. Heavy Equipment . Tenant shall give to Landlord notice prior to moving any heavy machinery, heavy equipment, freight, bulky matter, or fixtures (collectively, “ Equipment ”) into or out of the Project and shall pay to Landlord any costs actually incurred by Landlord in connection therewith. If such Equipment requires special handling, Tenant agrees (a) to employ only persons holding all necessary licenses to perform such work, (b) all work performed in connection therewith shall comply with all applicable laws, and (c) such work shall be done only during hours designated by Landlord.

8.6. No Representation of Compliance . The approval of Plans, or consent by Landlord to the making of any Alterations, does not constitute Landlord’s representation that such Plans or Alterations comply with any laws. Landlord shall not be liable to Tenant or any other party in connection with Landlord’s approval of any Plans, or Landlord’s consent to Tenant’s performing any Alterations. If any Alterations made by or on behalf of Tenant require Landlord to make any alterations or improvements to any portion of the Project to comply with any laws, Tenant shall pay all costs and expenses incurred by Landlord in connection with such alterations or improvements.

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9.1. Tenant’s Insurance .

(a) Tenant’s Coverage . From and after the Scheduled Commencement Date, Tenant shall obtain and keep in force the following insurance coverages:

(1) Commercial general liability insurance insuring Tenant’s use and occupancy of the Premises and use of the Common Areas, and covering personal and bodily injury, death, and damage to others’ property of not less than the Liability Limit. This policy shall include cross liability and severability of interests clauses, and be written on an occurrence, and not claims-made, basis. This policy shall name Landlord, the Building property manager, each secured lender, and any other party reasonably designated by Landlord as an additional insured (“ Additional Insured ”); provided , that the names and mailing addresses and interests of each of such parties are provided to Tenant.

(2) All risk insurance (including standard extended coverage endorsement perils, leakage from fire protective devices and other water damage) covering the full replacement cost of the Leasehold Improvements and Tenant’s Personal Property. This policy shall name Landlord and each Additional Insured as loss payee to the extent of their interest in the Leasehold Improvements provided the Landlord provides the name, address and interest of each party to be named loss payee. This policy shall include a provision or endorsement in which the insurer waives its right of subrogation against Landlord and each Additional Insured. Notwithstanding their interest as loss payee, if this Lease is not terminated pursuant to Article 10 and Tenant is not in monetary or Material Non-monetary Default, all insurance proceeds under the policies described in this Section 9.1(a)(2) and in Section 9.1(a)(8) shall be made available to Tenant for repair and restoration of the Leasehold Improvements. If this Lease is terminated pursuant to Article 10 and Tenant is not in monetary or Material Non-monetary Default, Tenant shall be entitled to those insurance proceeds under the policies described in this Section 9.1(a)(2) and in Section 9.1(a)(8) that are equal to the value of the Leasehold Improvements that were paid for by Tenant (not including the Construction Allowance or any other allowances for installation of improvements in the Premises, if any, paid by Landlord to Tenant (or paid to contractors or subcontractors at the direction of Tenant) hereunder) or pre-date the Execution Date (to the extent paid for by Tenant) and Landlord shall be entitled to those insurance proceeds under the policies described in this Section 9.1(a)(2) and in Section 9.1(a)(8) that are equal to the value of the Leasehold Improvements that were paid for by Landlord (specifically including the Construction Allowance and any other allowance for installation of improvements in the Premises, if any, paid to Tenant by Landlord (or paid to contractors or subcontractors at the direction of Tenant) hereunder).

(3) Business interruption insurance covering the perils described in Section 9.1(a)(2) with such limits as are reasonable and customary for businesses comparable to Tenant, to the extent that such insurance coverage is available at commercially reasonable rates.

(4) For any boiler or machinery owned by or installed by or on behalf of Tenant, boiler and machinery insurance, with a limit of at least the Liability Limit.

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(5) Insurance required by law, including workers’ compensation insurance.

(6) Employers liability insurance with limits not less than $1,000,000.00 for each accident, $1,000,000.00 for each disease for each employee, and $1,000,000.00 for disease in the aggregate.

(7) Commercial automobile liability insurance covering all owned, hired, and non-owned vehicles with a combined single limit of not less than $1,000,000.00 for each accident or person.

(8) Insurance covering the Leasehold Improvements and Tenant’s Personal Property against loss or damage due to earthquake or difference in conditions perils. Tenant may elect to self-insure this coverage. If Tenant does not elect to self-insure this coverage, then each of these policies shall name Landlord and each Additional Insured a loss payee to the extent of their interest in the Leasehold Improvements (which shall be as provided in Section 9.1(a)(2)) ; provided , that Landlord gives to Tenant the name, address, and interest of each party to be named loss payee.

(9) During the performance of any Alteration, until completion thereof, Builder’s Risk insurance on an “all risk” basis and on a completed value form including a Permission to Complete and Occupy endorsement, for full replacement value covering the interest of Landlord and Tenant (and their respective contractors and subcontractors) in all work incorporated in the Project and all materials and equipment in or about the Premises.

(10) Such other insurance in such amounts as Landlord may reasonably require from time to time; provided , that the same is then customarily being required from tenants by landlords of other first class office buildings in downtown Chicago.

(b) Insurers and Terms . Each policy required under Section 9.1(a) above shall be written with insurance companies licensed to do business in the state of Illinois having a rating of not less than A- and a Financial Size Class (“ FSC ”) of at least VII by A. M. Best Company, and be on terms that are reasonably acceptable to Landlord. Each policy of insurance required to be carried by Tenant shall, if then available from Tenant’s insurer on commercially reasonable terms, contain a provision that (1) no act or omission of Tenant shall affect or limit the obligation of the insurance company to pay the amount of any loss sustained by Landlord, and (2) shall be non-cancellable and/or no material change in coverage shall be made thereto unless the applicable insurance company shall have given to Landlord 30 days prior notice thereof.

(c) Proof of Insurance . Tenant shall provide Landlord with certificates of insurance or other reasonable proof that the coverage required under Section 9.1(a) above is in effect. Tenant shall provide reasonable proof of renewal or replacement at least 5 business days prior to any policy expiration date. Tenant’s failure to provide any insurance required by this Lease shall not be construed as a waiver of liability or any limit of damages, and Landlord and Tenant expressly agree that the requirement to carry insurance does not imply that such required insurance is adequate to fully compensate the insured parties for the damages so insured.

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(d) Waiver of Subrogation . Each policy of insurance required pursuant to Sections 9.1(a)(2) , (3) , (4) , and (8) shall include a provision or endorsement in which the insurer waives its right of subrogation against Landlord and each Additional Insured.

9.2. Landlord’s Insurance .

(a) Landlord’s Coverage . During the Term, Landlord shall obtain and keep in force the following insurance coverages:

(1) Commercial general liability insurance in an amount not less than $20,000,000.00 (including applicable umbrella coverage reserved, and specifically available, for the Building).

(2) All risk insurance (including standard extended coverage endorsement perils, leakage from fire protective devices and other water damage) covering the full replacement of the Base Building (other than footings and foundations), with a deductible not to exceed $100,000.00 (excluding any deductible for Named Windstorm, Flood, Earthquake, Turbines or Boiler and Machinery breakdowns, for which Landlord shall maintain market deductibles); provided , that Landlord may increase such deductible based on what is reasonably available in the market for such risks. Each of these policies shall include a provision or endorsement in which the insurer waives its right of subrogation against Tenant.

(3) Insurance covering the perils described in Section 9.2(a)(2) for Landlord’s loss of rental income or insurable gross profits. Each of these policies shall include a provision or endorsement in which the insurer waives its right of subrogation against Tenant.

(4) Boiler and machinery insurance. This policy shall include a provision or endorsement in which the insurer waives its right of subrogation against the Tenant.

(5) Other insurance that Landlord elects to maintain; provided , that such insurance is then reasonable and customary for comparable first class office buildings in the downtown Chicago market.

(b) Terms . Each of the policies required under Section 9.2(a) shall otherwise have those limits (except that the insurance described in Section 9.2(a)(2) shall always cover full replacement), deductibles, retentions and other terms that Landlord prudently determines and shall be written with insurance companies licensed to do business in the state of Illinois having a rating of not less than A- and a FSC of at least VII by A. M. Best Company.

10.1. Damage and Repair . If all or any portion of the Project is damaged by fire or other casualty, then the following provisions shall apply:

(a) Landlord’s Estimates . Landlord shall assess the damage to the Project (but not the Leasehold Improvements) and as soon as reasonably practicable notify Tenant of Landlord’s reasonable estimate of the time required to substantially complete repairs and restoration of the Project from the date of such estimate taking into account the time periods

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required to make insurance loss adjustments, obtain permits and engage contractors (“ Repair Estimate ”). The period of time set forth in the Repair Estimate is referred to as the “ Repair Estimate Period ”. In the Repair Estimate, Landlord shall also estimate the time period that the Premises will be Untenantable (the “ Interruption Period Estimate ”‘) taking into account any period of up to 120 days that will be required to restore or repair the Leasehold Improvements. Within thirty 30 days after the later of the casualty, issuance of the Repair Estimate, or, in the case of Landlord only, receipt of a denial of coverage from Landlord’s insurer, each of Landlord and Tenant may terminate the Lease by giving to the other written notice on the following conditions:

(1) Landlord may elect to terminate this Lease if the Premises or any material portion thereof is Untenantable and either:

(A) The Repair Estimate Period during which the Premises or any material portion thereof in any of the 10 South Wacker Building, the 20 South Wacker Building, or the 30 South Wacker Building will remain Untenantable exceeds 365 days, or

(B) The damage or destruction occurs in the last 12 Months of the Term and all options to extend the Term have expired; or

(C) The repair and restoration necessary so that no material portion of the Project will continue to be Untenantable is not substantially covered by insurance maintained or required to be maintained by Landlord (subject only to those deductibles or retentions Landlord elected to maintain) or Landlord’s insurer finally and unconditionally denies coverage.

(2) Tenant may elect to terminate this Lease if the Interruption Period Estimate exceeds 365 days.

(3) If Tenant so elects, Tenant may render void any election by Landlord to terminate this Lease pursuant to Section 10.1(a)(1)(A) by giving to Landlord written notice (a “ Voiding Notice ”) within 30 days after Landlord gives to Tenant such termination notice; provided , that (A) there are at least three years remaining in the Term, or, if there are fewer than three years remaining in the Term, that Tenant exercises, in accordance with this Lease, an available Extension Option at or prior to the time of the giving of such Voiding Notice, (B) the cost of the Base Building repairs will be covered by insurance in all material respects, excluding any deductibles or retentions Landlord elected to maintain, and no material amount of such cost is uninsured or subject to any final or unconditional denial of claim or coverage by any insurance provider, (C) Tenant covenants in writing to restore the Leasehold Improvements as required herein, and occupy that portion of the Premises occupied by Tenant prior to the Casualty, (D) less than 50% of the Building is damaged, and (E) Tenant shall not have the right to terminate this Lease pursuant to Section 10.1(a)(2) , and shall not terminate this Lease pursuant to Section 10.1(b)(1) so long as Landlord is diligently pursuing the repairs and restoration.

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(b) Repairs . If neither party terminates this Lease pursuant to Section 10.01(a) above or if Landlord terminates this Lease but Tenant timely gives to Landlord a Voiding Notice, then this Lease shall remain in full force and effect and the following provisions shall apply:

(1) Landlord shall repair and restore the Project (but not the Leasehold Improvements) to the condition existing prior to such damage, except for modifications required by law. Landlord shall perform such work diligently and continuously with the intent of completing such repair and restoration work on or before the expiration of the Repair Estimate Period. Notwithstanding anything contained in this Lease to the contrary, if Landlord fails to substantially complete the repair of any portion of the Project necessary for Tenant’s occupancy of the Premises for the purpose of repairing and restoring the Leasehold Improvements within 180 days after the last day of the Repair Estimate Period, subject to delays for insurance adjustments, delays caused by matters beyond Landlord’s reasonable control, and delays caused by Tenant (“ Final Repair Period ”), then Tenant may terminate this Lease by giving to Landlord written notice not later than 15 days after last day of the Final Repair Period. If Tenant gives to Landlord such notice then this Lease shall terminate effective as of the date such notice was given. If Tenant shall not timely give to Landlord such notice then Tenant’s right to terminate this Lease pursuant to this Section l0.1(b)(1) shall be void and of no further force or effect.

(2) Tenant shall repair and restore the Leasehold Improvements diligently and with reasonable promptness to the condition existing prior to such damage, but not less than then current Building Standards, except for modifications required by law.

10.2. Rent Abatement . If, as a result of the damage or destruction described in Section 10.1 , any portion of the Premises becomes Untenantable and Tenant does not actually use such Untenantable portion of the Premises for more than 3 consecutive business days, then Tenant’s Base Rent and, if applicable, Additional Rent for such Untenantable portion of the Premises not used by Tenant shall be abated from the date Tenant ceased such use until the earlier of the date (a) the damaged or destroyed portion of the Premises becomes tenantable for the operation of Tenant’s business, or (b) 120 days after Landlord completes Landlord’s repairs and restoration of the Base Building, including all Common Areas. Tenant’s sole remedy against Landlord for damage or destruction of any portion of the Premises is termination of this Lease pursuant to Section 10.1(b)(1) and abatement of Base Rent and Additional Rent under this Section 10.2 , and Landlord shall not be liable to Tenant for any other amount, including damages to Tenant’s Personal Property, consequential damages, actual or constructive eviction, or abatement of any other item of Rent.

11.1. Claims . “ Claims ” means any and all liabilities, losses, claims, demands, damages or expenses that are suffered or incurred by a party, including attorneys’ fees reasonably incurred by that party in the defense or enforcement of the rights of that party.

11.2. Landlord’s Waivers and Tenant’s Indemnity .

(a) Landlord’s Waivers . Landlord waives any Claims against Tenant and its Affiliates for perils insured or required to be insured by Landlord under Section 9.2(a)(2) and (3) , so long as such loss, injury or damage results from or in connection with this Lease or

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Tenant’s use and occupancy of the Premises and notwithstanding anything to the contrary in this Lease, in all events Landlord waives any Claims for any special or consequential damages (such as interruption of business, loss of income, or loss of opportunity) except to the extent that any such Claims are caused by the willful misconduct of Tenant or anyone for whom Tenant is legally responsible and except for any Claims resulting from Tenant’s Holdover in violation of Section 3.3 .

(b) Tenant’s Indemnity . Unless waived by Landlord under Section 11.2(a) , Tenant shall indemnify and defend Landlord and its Affiliates and hold each of them harmless from and against Claims arising from:

(1) Any accident or occurrence in, on, or about the Premises, except to the extent caused by the negligence or willful misconduct of Landlord or its Affiliates or of their agents or contractors, or;

(2) Any act or omission on the part of Tenant or any of Tenant’s Affiliates or their agents or contractors;

(3) Any claim for commission or other compensation by any person other than Broker for services rendered to Tenant in procuring this Lease; or

(4) Any breach, violation, or nonperformance of any covenant, condition, or agreement of this Lease on the part of Tenant to be fulfilled, kept, observed, or performed (it being acknowledged, however, that Tenant’s sole liability for a Holdover is as set forth in and limited by Section 3.3 ).

11.3. Tenant’s Waivers and Landlord’s Indemnity and Waiver .

(a) Tenant’s Waivers . Tenant waives any Claims against Landlord and Landlord’s Affiliates for:

(1) Perils insured or required to be insured by Tenant under Sections 9.1(a)(2) , (3) , (4) , and (8) ; or

(2) Loss or theft of property of Tenant or others;

(3) Except to the extent caused by the negligence or willful misconduct of Landlord or its Affiliates, damage caused by (A) damage to property of Tenant or others; (B) injury or damage to persons or property resulting from fire, explosion, falling plaster, escaping steam or gas, electricity, water, rain or snow, or leaks from any portion of the Project or from any pipes, appliances or plumbing, or from dampness; or (C) other tenants, occupants or persons in the Premises or other portions of the Project; or (D) the public or by construction of any private or public work; and

(4) Any breach, violation, or nonperformance of any covenant, condition, or agreement of this Lease on the part of Tenant to be fulfilled, kept, observed, or performed.

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Notwithstanding anything in this Lease to the contrary, in all events Tenant waives any Claims for any special or consequential damages (such as interruption of business, loss of income, or loss of opportunity), provided , that nothing herein shall limit Tenant’s rights under Section 4.1(b) .

(b) Landlord’s Indemnity and Waiver . Unless waived by Tenant under Section 11.3(a) , Landlord shall indemnify and defend Tenant and its Affiliates and hold each of them harmless from and against Claims arising from:

(1) Any accident or occurrence in, on, or about the Common Areas, except to the extent caused by the negligence or willful misconduct of Tenant, its Affiliates, their agents or their contractors;

(2) Any act or omission on the part of Landlord or any of Landlord’s Affiliates or their agents or contractors;

(3) Any claim for commission or other compensation by any person other than Broker for services rendered to Landlord in procuring this Lease; and

(4) Any breach, violation, or nonperformance of any covenant, condition, or agreement of this Lease on the part of Landlord to be fulfilled, kept, observed, or performed.

Notwithstanding anything in this Lease to the contrary, in all events Landlord waives any Claims for any special or consequential damages (such as interruption of business, loss of income, or loss of opportunity) except for any such claims arising from a Holdover pursuant to Section 3.3 , and then Tenant’s liability shall be as set forth in (and limited by) Section 3.3 .

11.4. Affiliates Defined . “ Affiliates ” means with respect to a party (a) each corporation or other entity that is a direct or indirect parent or subsidiary of that party, and (b) each corporation or other entity that is controlled by or under common control of a direct or indirect parent of such party. For purposes of the definition of “ Affiliates ”, “ control ” shall mean ownership of more than 50% of all of the voting stock or legal and equitable interest in the entity in question.

11.5. Defense of Claim . (a) If any claim that is within the scope of the indemnities set forth in this Article 11 is asserted against any indemnified party, then the indemnified party shall give prompt written notice (each, an “ Indemnified Party Notice ”) thereof to the indemnifying party (i.e., within a time period so as not to prejudice the indemnifying party’s or its insurer’s ability to defend effectively any action or proceeding brought on such claim) and the indemnifying party shall have the right to defend and control the defense of any action or proceeding brought on such claim with counsel chosen by the indemnifying party’s insurance company or by the indemnifying party subject to the approval of the indemnified party (such approval not to be unreasonably withheld). If the indemnified party fails promptly to give an Indemnified Party Notice or if the indemnified party shall not afford the indemnifying party the right to defend and control the defense of any such action or proceeding then, in either of such events, the indemnifying party shall have no obligation under the applicable indemnity set forth

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in this Lease with respect to such action or proceeding or other actions or proceedings involving the same or related facts. If the indemnifying party shall defend any such action or proceeding, then the following shall apply:

(1) the indemnified party shall cooperate with the indemnifying party (or its insurer) in the defense of any such action or proceeding in such manner as the indemnifying party (or its insurer) may from time to time reasonably request and the indemnifying party shall not be liable for the costs of any separate counsel employed by the indemnified party;

(2) the indemnifying party shall not be liable for any settlement made without the indemnifying party’s consent;

(3) if such action or proceeding can be settled by the payment of money and without the need to admit liability on the indemnified party’s part and without any civil or criminal penalties being imposed upon the indemnified party, then the indemnifying party shall have the right to settle such action or proceeding without the indemnified party’s consent and the indemnifying party shall have no obligation under the applicable indemnity set forth in this Lease with respect to such action or proceeding or other actions or proceedings involving the same or related facts if the indemnified party refuses to agree to such a settlement; and

(4) if such action or proceeding cannot be settled merely by the payment of money and without the need to admit liability on the indemnified party’s part and without any civil or criminal penalties being imposed upon the indemnified party, then the indemnifying party shall not settle such action or proceeding without the indemnified party’s consent (which consent shall not be unreasonably withheld, conditioned or delayed) and if the indemnified party unreasonably withholds, conditions or delays its consent to any such settlement, then the indemnifying party shall have no obligation to further defend (or pay for the defense of) such action or proceeding or other actions or proceedings involving the same or related facts, and shall not be liable for Claims arising therefrom in excess of the amount of Claims the indemnifying party would have paid pursuant to the proposed settlement offer.

(b) If an indemnifying party shall, in good faith, believe that a Claim set forth in an Indemnified Party Notice is or may not be within the scope of the indemnifying party’s indemnity set forth in this Lease then, pending determination of that question, the indemnifying party shall not be deemed to be in default under this Lease by reason of its failure or refusal to indemnify and hold harmless any indemnified party therefrom or to pay such costs, expenses and liabilities; provided , that if it shall be finally determined by a court of competent jurisdiction that such Claim was within the scope of such indemnifying party’s indemnity set forth in this Lease then such indemnifying party shall be liable for any judgment or reasonable settlement and any reasonable legal fees incurred by the party entitled to indemnity hereunder, together with interest at the Default Rate on the outstanding amount of all such costs and expenses from the date paid by the indemnified party (or, if later, the date the notice of such Claim was given to the indemnifying party) until the indemnifying party pays to the indemnified party all such amounts in full.

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11.6. Survival of Waivers and Indemnities . Landlord’s and Tenant’s waivers and indemnities under Sections 11.2 and 11.3 shall survive the expiration or early termination of this Lease.

12.1. Taking . “ Taking ” means all or a portion of the Project is acquired by or through a governmental or quasi-governmental entity by exercise of a right of eminent domain or other condemnation authority. If a Taking occurs then the following provisions shall apply:

(a) Total Taking . If, because of a Taking, substantially all of the Premises are Untenantable for substantially all of the remaining Term, then this Lease shall terminate on the date of the Taking.

(b) Partial Taking . If a Taking does not cause this Lease to be terminated pursuant to Section 12.1(a) , then Landlord shall restore to the extent practicable (and alter, as necessary) the Common Areas, the Premises (and those other portions of the Project that Tenant has rights to use under this Lease prior to the Taking) to be tenantable, unless the Lease is terminated by either Landlord or Tenant under the following circumstances:

(1) Landlord may terminate this Lease upon giving to Tenant 60 days prior written notice if Landlord reasonably determines that it is uneconomical to restore or alter the Project to be tenantable.

(2) Tenant may terminate this Lease upon giving to Landlord 60 days prior written notice if the Taking causes more than 33% of the Premises to be Untenantable for the remainder of the Term, and Tenant cannot economically conduct Tenant’s business in the remaining Premises.

(c) If this Lease is not terminated under Sections 12.1(a)  or (b) , the Rent (Base Rent and Additional Rent) shall be reduced for the term of the Taking based upon the RSF (of Office Space) or USF (of Fixed Term Support Space) of the Premises (as applicable) made Untenantable by the Taking.

12.2. Awards . Landlord shall be entitled, except as otherwise hereinafter provided, to receive the entire award in the Taking proceeding, including, without limitation, any award made for the value of the estate vested by this Lease in Tenant or any value attributable to the unexpired portion of the Term, and Tenant hereby assigns to Landlord any and all right, title and interest of Tenant now or hereafter arising in or to any such award or any part thereof, and Tenant shall be entitled to receive no part of such award; provided , that nothing shall preclude Tenant from participating in any such condemnation proceeding to claim or receive from the condemning authority any compensation to which Tenant may otherwise lawfully be entitled in such case in respect of Tenant’s Personal Property, the unamortized value of the Leasehold Improvements (but only to the extent such Leasehold Improvements were paid for by Tenant (and not reimbursed by Landlord)), or moving expenses; provided , that the same do not include any value of the estate vested by this Lease in Tenant or of the unexpired portion of the Term and do not reduce the amount available to Landlord or materially delay the payment thereof.

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12.3. Temporary Taking . If all or any portion of the Premises is Taken temporarily during the Term for any public or quasi-public use or purpose, Tenant shall give to Landlord prompt notice thereof and the Term shall not be reduced or affected in any way and Tenant shall continue to pay all Rent payable by Tenant without reduction or abatement and to perform all of Tenant’s other obligations under this Lease, except to the extent Tenant is prevented from doing so by the condemning authority, and Tenant shall be entitled to receive any award or payment from the condemning authority for such use, which shall be received, held and applied by Tenant as a trust fund for payment of the Rent falling due.

13.1. Transfer Defined . “ Transfer ” means any:

(a) Sublease of all or any portion of the Premises, or assignment, mortgage, hypothecation or other conveyance of an interest in this Lease either voluntarily or involuntarily or by operation of law. Any material modification, amendment, or extension of a sublease, and any agreement by which a landlord of a building other than the Project or its affiliate agrees to assume the obligations of Tenant under this Lease, shall be deemed a sublease for the purposes of this Article 13.1 ;

(b) Use of the Premises with Tenant’s consent by anyone other than Tenant and its employees in the ordinary course of Tenant’s business; provided , that “ Transfer ” shall not include the use of the Premises by a Desk Space User; provided , that (1) any such use or occupancy of desk or office space shall be without the installation of any separate entrance, (2) each Desk Space User shall use the Premises in accordance with all of the provisions of this Lease, and only for the use expressly permitted pursuant to this Lease, (3) in no event shall the use of any portion of the Premises by a Desk Space User create or be deemed to create any right, title or interest of such Desk Space User in any portion of the Premises or this Lease, (4) such “desk sharing” arrangement shall terminate automatically upon the termination of this Lease, (5) such Desk Space User shall not have any signage outside of the Premises, (6) each Desk Space User shall be engaged in a business or activity which is in keeping with standards of the Building and (7) such desk sharing arrangement is for a valid business purpose and not to circumvent the provisions of this Article 13 . “ Desk Space User ” means a bona fide member, client, service provider, regulatory authority or other person or entity with which Tenant has an active and meaningful business relationship and is using the relevant portion of the Premises for a purpose associated with the business of Tenant;

(c) Transfer of 51% or more of Tenant’s assets, shares (except shares transferred by public trading or as the result of an acquisition, merger or consolidation with the resulting entity having equity securities traded on a public exchange), membership interests, partnership interests or other ownership interests; or

(d) Transfer of effective control of Tenant (except shares transferred by public trading or as the result of an acquisition, merger or consolidation with the resulting entity having equity securities traded on a public exchange).

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13.2. Prohibited Transfers . Tenant may not enter into a Transfer or other agreement to use or occupy the Premises that provides for rent or other compensation based in whole or in part on the net income or profits from the business operated in the Premises. Tenant may not enter into a Transfer if the proposed transferee is directly or indirectly related to the Landlord under Section 856 of the Code; provided , that Landlord has given to Tenant notice and appropriate evidence thereof. Any such Transfers in violation of this Section 13.2 shall be considered null, void and of no force or effect.

13.3. Consent Not Required .

(a) Upon giving notice to Landlord, but without Landlord’s prior consent, Tenant may effect a Transfer to a Permitted Transferee; provided , that as to any permitted Transfer resulting from a transaction involving publicly traded equity securities, Tenant may give to Landlord notice thereof promptly after such Transfer occurs. A “ Permitted Transferee ” is any person or entity that meets the requirements of either Section 13.3(a)(1) or (2) :

(1) The transferee (who in the case of Section 13.1(c) or (d)  may be Tenant itself) is an Affiliate of Tenant; provided , that in the case of any such Transfer, the Transfer is for a valid business purpose and not to avoid any obligations under this Lease, and the transferee assumes by written instrument satisfactory to Landlord all of Tenant’s obligations under this Lease.

(2) The transferee (who in the case of Section 13.1(c) or (d) may be Tenant itself) is (A) an entity created by, or resulting from, merger, acquisition, consolidation, reorganization or recapitalization of, by, or with Tenant or (B) a purchaser of all or substantially all of Tenant’s assets; provided , that in the case of both clauses (A)  and (B) , that the transferee assumes by written instrument satisfactory to Landlord all of Tenant’s obligations under this Lease (unless Tenant is the surviving entity in a merger), such Transfer is for a valid business purpose and not to avoid any obligations under this Lease, and the transferee shall have, immediately after giving effect to such Transfer, a net worth (computed in accordance with GAAP) at least equal to $200,000,000.00.

(b) In addition to Tenant’s Transfer rights (including the rights to sublease) set forth in Section 13.3(a) , upon giving to Landlord notice, but without Landlord’s prior consent, Tenant may sublet to one or more subtenants up to 20% of the Premises in the aggregate at any date of determination (“ Permitted Sublease ”); provided , that:

(1) Any Permitted Sublease shall not permit the subtenant thereunder to use, or permit the use of, the Premises or any part thereof for:

(A) The offices or business of a governmental or quasi-governmental bureau, department or agency, foreign or domestic, including an autonomous governmental corporation or diplomatic or trade mission;

(B) Conduct or maintenance of any gambling or gaming facilities, facilities for any political organization (excluding Tenant’s PAC) or any social or other club, or a school or employment or placement agency; or

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(C) Any use not included as a Use, or which would violate any agreement which affects the Building or binds Landlord, including without limitation, any exclusive uses granted to then existing tenants of the Building;

(2) Such proposed subtenant is not named on the list of Specially Designated Nationals and Blocked Persons maintained by the Office of Foreign Assets Control of the United States Department of the Treasury or any such similar list maintained by the state or federal government; and

(3) Except if such proposed subtenant is a member firm of Tenant or Tenant’s customer or of an Affiliated Entity or its customer, such proposed subtenant is not (A) an existing tenant of the Building or an Affiliate of an existing tenant of the Building, or (B) a party with whom Landlord is actively negotiating to lease space in the Building (or has, in the 6 months prior thereto, been actively negotiating to lease space in the Building); and in each case space of a comparable size is then available (or is anticipated to be available no later than the date on which the proposed sublease is scheduled to commence) for lease in the Building.

13.4. Consent Required . Each proposed Transfer other than those prohibited under Section 13.2 or permitted under Section 13.3 shall be subject to Landlord’s prior written consent, in which case the parties will proceed as follows:

(a) Tenant’s Notice . Tenant shall give to Landlord notice at least 30 days prior to the proposed Transfer of the name and address of the proposed transferee and the proposed use of the Premises, and include in such notice the Transfer documents and copies of the proposed transferee’s balance sheets and income statements (both current and for the past 2 years to the extent available) and any other information Landlord may reasonably request.

(b) Landlord’s Rights . Within 30 days after Tenant gives to Landlord Tenant’s complete notice pursuant to Section 13.4(a) , Landlord may:

(1) If the proposed Transfer is either an assignment of this Lease or a sublease that in aggregate with the other subleases of the Premises in effect on the date of determination covers more than 20% of the Premises and is for all or substantially all of the then remaining Term, terminate this Lease in respect of the space that Tenant proposes to sublease (or entirely in the case of a proposed assignment) as of the proposed Transfer date. If Landlord exercises its option to terminate this Lease with respect to all or a portion of the Premises, (A) this Lease shall end and expire with respect to all or a portion of the Premises, as the case may be, on the date that such assignment or sublease was to commence, (B) Rent shall be apportioned, paid or refunded as of such date, (C) Tenant, upon Landlord’s request, shall enter into an amendment of this Lease ratifying and confirming such total or partial termination, and setting forth any appropriate modifications to the terms and provisions hereof, and (D) Landlord shall be free to lease the Premises (or any portion thereof) to Tenant’s prospective assignee or subtenant or to any other party. Landlord shall pay all costs to make each of the transferred space and the remainder of the Premises a self-contained rental unit and to install any required Building corridors; or

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(2) Consent or deny consent to the proposed Transfer; which consent shall not be unreasonably withheld if:

(A) The proposed use is consistent with the Use, and will not cause Landlord to be in breach of any lease, law or other agreement affecting the Project;

(B) The proposed transferee is typical of tenants that directly lease premises in comparable first class office buildings in downtown Chicago;

(C) The proposed transferee is not a governmental or diplomatic entity;

(D) The proposed transferee is not named on the list of Specially Designated Nationals and Blocked Persons maintained by the Office of Foreign Assets Control of the United States Department of the Treasury or any such similar list maintained by the state or federal government;

(E) If space of a comparable size is then available (or is anticipated to be available no later than the date on which the proposed sublease or assignment is scheduled to commence) in the Building for lease by such proposed transferee, such proposed transferee (except for a proposed transferee that is a member firm of Tenant or Tenant’s customer or of an Affiliated Entity of Tenant or such Affiliated Entity’s customer) is not an existing tenant or an Affiliate of an existing tenant, or a party with whom Landlord is actively negotiating to lease space in the Building (or has, in the last 6 months, been actively negotiating to lease space in the Building);

(F) Tenant is not in Default under this Lease;

(G) With respect to the third floor (and the seventh floor, if Tenant is leasing same as contemplated herein) of the 20 South Wacker Building, so long as any such space is not separately demised or physically subdivided in any manner which interferes with any Landlord services provided to such floor(s) under this Lease (including Standard Services); and

(H) Tenant shall have reimbursed Landlord for all reasonable expenses incurred by Landlord in consenting to such assignment or sublease, including any investigations as to the acceptability of the Transferee and all legal costs reasonably incurred in connection with the granting of any requested consent.

(c) Compelling Consent . If Landlord does not consent to a Transfer, Tenant’s sole remedy against Landlord for breach of its obligation to be reasonable shall be an action for specific performance or declaratory relief, and Tenant may not terminate this Lease or seek monetary damages, unless Tenant is able to demonstrate bad faith or willful misconduct.

(d) Assignment and Sublease Requirements . With respect to each and every subletting and/or assignment pursuant to the provisions of this Lease:

(1) the form of the proposed assignment or sublease shall be reasonably satisfactory to Landlord;

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(2) no sublease of the entire Premises shall be for a term ending later than one day prior to the Expiration Date;

(3) no Transferee shall take possession of any portion of the Premises until an executed counterpart of such sublease or assignment has been delivered to Landlord and approved by Landlord as provided in Section 13.4(a) , if this Lease requires approval of such sublease or assignment; and

(4) each sublease shall be subject and subordinate to this Lease and to the matters to which this Lease is or shall be subordinate, and Tenant and each Transferee shall be deemed to have agreed that upon any termination of this Lease, Tenant has hereby assigned to Landlord, and Landlord may, at its option, accept such assignment of, all right, title, and interest of Tenant as sublandlord under such sublease, together with all modifications, extensions, and renewals thereof then in effect and such Transferee shall, at Landlord’s option, attorn to Landlord pursuant to the then executory provisions of such sublease, except that Landlord shall not be (A) liable for any previous act or omission of Tenant under such sublease, (B) subject to any counterclaim, offset, or defense not expressly provided in such sublease or which theretofore accrued to such Transferee against Tenant, (C) bound by any previous modification of such sublease not consented to by Landlord or by any prepayment of more than one month’s rent, (D) bound to return such Transferee’s security deposit, if any, except to the extent Landlord shall receive actual possession of such deposit and such Transferee shall be entitled to the return of all or any portion of such deposit under the terms of such Transferee’s sublease, or (E) obligated to make any payment to or on behalf of such Transferee, or to perform any work in the sublet space or the Building, or in any way to prepare the subleased space for occupancy, beyond Landlord’s obligations under this Lease. The provisions of this Section 13.4(d)(5) shall be self-operative, and no further instrument shall be required to give effect to this provision; provided , that Transferee shall execute and deliver to Landlord any instruments Landlord may reasonably request to evidence and confirm such subordination and attornment.

13.5. Payments to Landlord . If Tenant enters into any assignment or sublease (other than an assignment or sublease pursuant to Section 13.3(a)) , Tenant shall, within 60 days after Landlord’s consent to such assignment or sublease (or, if such assignment or sublease is permitted hereunder without Landlord’s prior consent, within 60 days after the effective date of such assignment or sublease), deliver to Landlord a list of Tenant’s reasonable third-party brokerage fees, legal fees and architectural fees paid or to be paid in connection with such transaction, the cost of Alterations paid for by Tenant to effect such Transfer, and, in the case of any sublease, any actual costs incurred by Tenant in separately demising the sublet space (collectively, “ Transaction Costs ”), together with a list of all of Tenant’s Property to be transferred to such Transferee. In consideration of such assignment or subletting, Tenant shall pay to Landlord:

(a) In the case of an assignment, on the effective date of the assignment, 50% of all sums and other consideration paid to Tenant by the assignee for or by reason of such assignment (including key money, bonus money and any sums paid for services rendered by

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Tenant to the assignee in excess of fair market value for such services and sums paid for the sale or rental of Tenant’s Property, less the then fair market or rental value thereof) after first deducting the Transaction Costs; or

(b) In the case of a sublease, 50% of any consideration payable under the sublease to Tenant by the sublessee which exceeds on a per square foot basis the Base Rent, Tenant’s Share of Expenses and Tenant’s Share of Taxes accruing during the term of the sublease in respect of the sublet space (together with any sums paid for services rendered by Tenant to the sublessee in excess of fair market value for such services and sums paid for the sale or rental of Tenant’s Property, less the then fair market or rental value thereof) after first deducting the Transaction Costs. The sums payable under this clause shall be paid by Tenant to Landlord monthly as and when paid by the subtenant to Tenant.

Landlord and Landlord’s authorized representatives shall have the right at all reasonable times to audit the books, records and papers of Tenant relating to any Transfer (other than a Transfer pursuant to Section 13.3(a) ), and shall have the right to make copies thereof.

13.6. Effect of Transfers . No Transfer shall release Tenant from any obligation under this Lease. Landlord’s acceptance of a payment from any person or entity other than Tenant shall not constitute a waiver of Tenant’s obligations under this Article 13 . Any Transfer in violation of this Article 13 is void and of no force or effect. If Tenant is in Default of this Lease, Landlord may proceed against Tenant without exhausting any remedies against any transferee and may require (by giving to any transferee written notice) any transferee to pay rent owed Tenant directly to Landlord (which Landlord shall apply against Tenant’s Lease obligations). Termination of this Lease for any reason shall not result in a merger of estates. Each sublease shall be deemed terminated upon termination of this Lease unless Landlord notifies the subtenant in writing of Landlord’s election to assume any sublease, in which case the subtenant shall attorn to Landlord under the executory terms of the sublease. Landlord’s consent to any assignment or subletting shall not relieve Tenant from the obligation to obtain Landlord’s consent to any further assignment or subletting. In no event shall any subtenant assign or encumber its sublease or further sublet any portion of its sublet space, or otherwise suffer or permit any portion of the sublet space to be used or occupied by others.

13.7. Indemnity . Tenant shall indemnify, defend, protect and hold harmless Landlord from and against any and all Claims against Landlord by any Transferee or anyone claiming under or through any Transferee or by any brokers or other persons or entities claiming a commission or similar compensation in connection with the proposed assignment or sublease, irrespective of whether Landlord shall give or decline to give its consent to any proposed assignment or sublease, or if Landlord shall exercise any of its options under this Article 13 .

13.8. Limitation on Consent . If Landlord consents to a proposed assignment or sublease and Tenant fails to execute and deliver to Landlord such assignment or sublease within 180 days after the giving of such consent, or the amount of space subject to any such sublease varies by more than 10% from that specified in the notice given by Tenant to Landlord pursuant to Section 13.4(a) , or the net effective rent payable under such sublease is less than 90% of the net effective rent specified in such notice, or if there are any material changes in the terms and

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conditions of the proposed assignment or sublease such that Landlord would initially have been entitled to refuse its consent to such Transfer under this Article 13 , then Tenant shall again comply with all of the provisions and conditions of this Article 13 before assigning this Lease or subletting all or any portion of the Premises.

14.1. Landlord’s Transfer . Landlord’s right to transfer any interest in the Project or this Lease is not limited by this Lease, except as expressly provided in this Article 14 . Upon any such transfer, Tenant will attorn to Landlord’s transferee and Landlord will be released from liability under this Lease, except for any Lease obligations accruing before the transfer that are not assumed by the transferee.

14.2. Attornment . (a) Subject to the provisions of Section 14.2(d) below, this Lease is subject and subordinate to all Mortgages and Superior Leases. Tenant shall from time to time within 10 days after request from Landlord execute and deliver any documents or instruments that may be reasonably required by any Mortgagee or Lessor and are reasonably satisfactory to Tenant to confirm any subordination. “ Mortgage ” means any mortgage, trust indenture or other financing document which may now or hereafter affect all or any portion of the Premises, the Project, the Building or any Superior Lease and the leasehold interest created thereby, and all renewals, extensions, supplements, amendments, modifications, consolidations and replacements thereof or thereto, substitutions therefor, and advances made thereunder. “ Mortgagee ” means any mortgagee, trustee or other holder of a Mortgage. “ Superior Lease ” means any ground or underlying lease of the Project or any part thereof heretofore or hereafter made and all renewals, extensions, supplements, amendments, modifications, consolidations, and replacements thereof. “ Lessor ” means a lessor under a Superior Lease.

(b) Any Mortgagee may elect that this Lease shall have priority over the Mortgage and, upon notification to Tenant by such Mortgagee, this Lease shall be deemed to have priority over such Mortgage, regardless of the Execution Date. Tenant shall execute and deliver to Landlord, within 15 business days after request, any amendment of this Lease reasonably requested by a Mortgagee; provided that such amendment shall not (i) reduce or extend the Term, (ii) increase the Rent, (iii) reduce the area of the Premises, (iv) increase Tenant’s obligations or decrease Tenant’s rights under this Lease in any respect, or (v) decrease Landlord’s obligations or increase Landlord’s rights under this Lease in any respect. Landlord shall, within 45 days of Landlord’s receipt of Tenant’s invoice therefor, reimburse Tenant for its reasonable out-of-pocket legal fees in connection with the review and preparation of such amendment requested by a Mortgagee, whether or not Tenant agrees that the request meets the foregoing conditions.

(c) Subject to the following provisions of this Section 14.2(c) . Landlord may elect, at any time during the Term, to convert the Project (or any part thereof) to condominium ownership or may subject the Project (or any part thereof) to a condominium declaration, by laws and other instruments (collectively, the “ Declaration ”) which may be recorded regardless of the reason therefor, in order to subject the Project (or any part thereof) to a condominium form of ownership pursuant to the Illinois Condominium Property Act or any successor law; provided , that (i) there shall never be more than one Landlord under this Lease ( i.e. , all portions of the

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Premises must be owned by the same entity at any one time), (ii) the Declaration does not by its terms (A) reduce or extend the Term, (B) increase the Rent, (C) reduce the area of the Premises, (D) increase Tenant’s obligations or decrease Tenant’s rights under this Lease in any respect, (E) decrease Landlord’s obligations or increase Landlord’s rights under this Lease in any respect, or (F) increase any Expenses reimbursed by Tenant under this Lease and (iii) this Lease remains superior to the Declaration. Tenant, at no cost and expense to Tenant, shall cooperate with Landlord as reasonably requested by Landlord in connection with this Section 14.2(c) .

(d) As a condition to Tenant’s agreement hereunder to subordinate Tenant’s interest in this Lease to any existing or future Mortgage and/or any Superior Lease made between Landlord and such Mortgagee and/or Lessor, Landlord shall obtain from each Mortgagee or Lessor an agreement, substantially in the form of Exhibit I annexed hereto (with such changes thereto as are reasonably acceptable to Tenant and such Mortgagee and/or Lessor) or such other form reasonably acceptable to Tenant and such Mortgagee and/or Lessor (any such agreement, a “ Non-Disturbance Agreement ”). If any Lessor or Mortgagee executes and delivers to Landlord a Non-Disturbance Agreement and Landlord delivers the same to Tenant, and Tenant either fails or refuses to execute and deliver said Non-Disturbance Agreement within 20 days following Landlord’s delivery of such Non-Disturbance Agreement to Tenant, this Lease shall be subject and subordinate to such Superior Lease or Superior Mortgage and Tenant shall automatically be deemed to be subject to and subordinate to such Superior Lessor or Superior Mortgagee and Landlord shall have no further obligation to obtain a Non-Disturbance Agreement for Tenant from such Lessor or Mortgagee.

14.3. Estoppel Certificate . Within 10 days after receipt of a written request, Tenant or Landlord, as applicable, will execute, acknowledge and deliver to the requesting party a certificate upon which the requesting party and each existing or prospective Encumbrance holder or prospective purchaser of the Project or transferee of any Transfer may rely (for estoppel purposes only) confirming the following (or specifying any exceptions to the following) as of the date of such certificate:

(a) The Scheduled Commencement Date and Expiration Date;

(b) The documents that constitute the Lease, and that the Lease is unmodified and in full force and effect;

(c) The date through which Base Rent, Additional Rent and other Rent has been paid;

(d) To the knowledge of the certifying party, that neither Landlord nor Tenant is in default under this Lease;

(e) To the knowledge of the certifying party, that Landlord has satisfied all Lease obligations to improve the Premises (or provide Tenant an allowance therefor) and Tenant has accepted the Premises;

(f) To the knowledge of the certifying party, that Tenant (and other occupants permitted under Article 13 without a sublease or assignment) are the sole occupants of the Premises; and

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(g) Such other matters concerning this Lease or Tenant’s occupancy that the requesting party may