OFFICE LEASE AGREEMENT

Exhibit 10.16

OFFICE LEASE AGREEMENT

     THIS OFFICE LEASE AGREEMENT (this “ Lease ”) is dated as of the 15th day of December, 2006, by and between WASHINGTON TELEVISION CENTER LLC, a District of Columbia limited liability company (“ Landlord ”), and BLACKBOARD INC., a Delaware corporation (“ Tenant ”).

ARTICLE I
DEFINITIONS

     1.1 Building : The building located at 650 Massachusetts Avenue, NW, Washington, D.C. 20001 containing approximately Two Hundred Ninety-One Thousand Sixty-Three (291,063) square feet of rentable area.

     1.2 Leased Premises : One Hundred Eleven Thousand Eight Hundred Ninety-Five (111,895) square feet of rentable area consisting of approximately Thirty-Five Thousand Four Hundred Thirty-Two (35,432) rentable square feet on the entire eighth (8 ^th ) floor of the Building, approximately Thirty-Five Thousand Four Hundred Thirty-Two (35,432) rentable square feet on the entire seventh (7 ^th ) floor of the Building, approximately Thirty-Five Thousand Four Hundred Thirty-Two (35,432) rentable square feet on the sixth (6 ^th ) floor of the Building, and approximately Five Thousand Five Hundred Ninety-Nine (5,599) rentable square feet on the first (1 ^st ) floor of the Building (the “ First Floor Space ”), all as more particularly designated on Exhibit A (collectively, the “ Premises ”).

     1.3 Lease Term : Ten (10) years from the Lease Commencement Date unless such term shall be terminated earlier or extended in accordance with the provisions of this Lease.

     1.4 Anticipated Delivery Date : March 8, 2007.

     1.5 Base Rent :

     (a)  Premises Base Rent: An amount during each Lease Year equal to the product of (x) the Premises Base Rent Per Square Foot (as shown in the chart below) in effect during the applicable Lease Year, and (y) the number of square feet of rentable area in the Premises. If the number of rentable square feet of rentable area in the Premises is 111,895, the Premises Base Rent is as follows:

If the number of rentable square feet in the Premises changes in accordance with the terms of this Lease, e.g., pursuant to Article XXVIII , then the foregoing Premises Base Rent chart shall be updated by amendment to this Lease showing the revised number of rentable square feet in the

Premises and the revised Annual Base Rent (and revised Monthly Base Rent). Notwithstanding any update to the foregoing chart, the Premises Base Rent Per Square Foot will not change.

          (b)  Storage Space Base Rent : An amount during each Lease Year equal to the product of (x) the Storage Space Base Rent Per Square Foot (as shown on the chart below) in effect during the applicable Lease Year, and (y) the number of square feet of rentable area in the Storage Space (hereinafter defined). If the number of rentable square feet of rentable area in the Storage Space is 1,000, the Storage Space Rent is as follows:

     1.6 Renewal Rights : Tenant shall have the option to renew the Term of the Lease for two (2) additional five (5) year periods pursuant to the terms of Article XXVII of the Lease.

     1.7 Expansion Option : Tenant shall have the option to expand the Premises in accordance with the provisions of Article XXVIII of this Lease.

     1.8 Security Deposit : Tenant shall deliver to Landlord a security deposit pursuant to the terms of Article VI of this Lease as follows: (i) one-half of such security deposit within the later of (a) five (5) business days after the execution of this Lease, and (b) five (5) business days after the lender’s execution and delivery of the SNDA (hereinafter defined), and (ii) the remaining one-half within five (5) business days after Landlord delivers any portion of the Premises to Tenant, and as a condition to Landlord’s obligation to pay amounts to Tenant in accordance with Exhibit B attached hereto.

     1.9 Brokers : Transwestern Commercial Services (“ Landlord’s Broker ”) and Studley, Inc. (“ Tenant’s Broker ”).

     1.10 Tenant Notice Address : Blackboard Inc., 1899 L Street, NW, 5 ^th Floor, Washington D.C., 20036, Attention: General Counsel, until Tenant has commenced beneficial use of the Premises, and the Premises, after Tenant has commenced beneficial use of the Premises, Attention: General Counsel, with a copy to Venable LLP, 575 7 ^th Street, NW, Washington, D.C. 20004; Attention: Philip M. Horowitz, Esq. In addition to the foregoing notice parties, copies of notices will also be delivered to Blackboard Inc., 1899 L Street, NW, 5 ^th Floor, Washington D.C., 20036, Attention: (i) Deputy General Counsel, and (ii) Chief Financial Officer, until Tenant has commenced beneficial use of the Premises, and the Premises, after Tenant has commenced beneficial use of the Premises, Attention: (i) Deputy General Counsel, (ii) Chief Financial Officer; provided, however, that the notice parties pursuant to this sentence are courtesy copies and will not be required in order to constitute “notice” under the terms of this Lease.

     1.11 Landlord Notice Address : USP Management LLC, 7777 Leesburg Pike, Suite 401N, Falls Church, Virginia 22043, Attention: Bruce Mahen, Vice President Asset Management, with copies to: USP Development LLC, 7777 Leesburg Pike, Suite 402N, Falls Church, Virginia 22043, Attention: Richard Wojcik, President, and Pillsbury Winthrop Shaw Pittman LLP, 2300 N Street, NW, Washington, D.C. 20037, Attention: John Engel, Esq.

     1.12 Building Hours : 8:00 a.m. to 7:00 p.m. on Monday through Friday and 9:00 a.m. to 3:00 p.m. on Saturday, but specifically excluding (i) the dates on which the federal government observes New Year’s Day, Martin Luther King Day, Washington’s Birthday (President’s Day), Memorial Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day, and (ii) such other legal holidays observed by Landlord provided that any such legal holidays recognized by Landlord shall be a Federal holiday recognized by a majority of other landlords of first class office buildings in Washington D.C. Notwithstanding the terms of subpart (ii) of the preceding sentence, Columbus Day and Veteran’s Day will not be excluded from Building Hours.

     1.13 Guarantor(s) : N/A.

     1.14 Parking Permits : Not more than ninety (90) unreserved Parking Permits (based on a ratio of one (1) permit per one thousand two hundred fifty (1,250) rentable square feet in the Premises) to be leased by Tenant, at Tenant’s option and at Tenant’s cost, pursuant to the provisions of Article XXIV below. In the event Tenant leases additional space in the Building, Tenant’s allotment of Parking Permits shall be increased based upon one (1) additional permit for each additional one thousand two hundred fifty (1,250) square feet of rentable area leased by Tenant, and in the event Landlord recaptures any portion of the Premises pursuant to Section 8.4 below, Tenant’s allotment of Parking Permits shall decrease proportionately.

     1.15 Landlord Payment Account : Washington Television Center LLC; wiring instructions as follows: ABA number 054001220, Account number 2000013850122, Wachovia Bank, Washington, D.C.

ARTICLE II
PREMISES

     2.1 Tenant hereby leases from Landlord, and Landlord hereby leases to Tenant, the Premises for the Lease Term and upon the conditions and covenants set forth in this Lease. Tenant will have the non-exclusive right to use, at no additional charge to Tenant except as set forth in Article V of the Lease, the common and public areas of the Building for ingress and egress to the Premises and to use the roof terrace, which if constructed by Tenant at Tenant’s sole cost and expense pursuant the requirements set forth in Article IX hereof and in Exhibit B attached hereto, shall be made available to Tenant for its exclusive use after the Lease Commencement Date (as hereinafter defined), subject to Landlord’s access to such roof terrace at all times for inspection, maintenance, repair and the like, provided further that such exclusive use will be to the exclusion of other tenants in the Building (and Landlord except as otherwise provided herein) so long as Tenant or a Permitted Transferee (and expressly excluding all subtenants or assignees) is leasing at least seventy thousand (70,000) rentable square feet in the Building. With respect to Landlord’s entry on the roof terrace, except in the event of an emergency, Landlord shall endeavor to give Tenant advance notice of any such entry and use commercially reasonable efforts to minimize disruption to Tenant’s use of such roof terrace during such entry. Landlord shall maintain the roof terrace, and Tenant shall reimburse Landlord for the entire cost of such maintenance from time to time (and in no event later than thirty (30) days after written invoice) as additional rent hereunder; provided, however, if such use of the roof terrace by Tenant becomes non-exclusive due to Tenant’s failure to meet the foregoing square footage requirement, then the cost of such maintenance by Landlord will be an Operating Expense (hereinafter defined) and shall be subject to the terms of Article V of this Lease. In addition, the use of the roof terrace (if constructed in accordance with the terms of this Lease) will be subject to reasonable written rules and regulations promulgated by Landlord and delivered to Tenant from time to time, so long as such rules and regulations do not materially adversely affect Tenant’s right to use such roof terrace. If the roof terrace is constructed by Tenant in accordance with the terms of this Lease and such roof terrace is in substantially in the eastern portion of the Massachusetts Ave. wing of the Building, then from and after such construction by Tenant and thereafter so long as Tenant or a Permitted Transferee (and expressly excluding all subtenants or assignees) is leasing at least seventy thousand

(70,000) rentable square feet in the Building, Landlord shall use reasonable efforts to locate any additional signs or equipment on the roof in a manner that minimizes interference with the use of such roof terrace, provided that it in no event will Landlord be obligated to (i) expend any material additional amounts in connection with such efforts or (ii) relocate any signs or equipment on the roof of the Building as of the date Tenant commences construction of the rooftop terrace in accordance with the terms of this Lease. Except as may otherwise be expressly provided in this Lease, the lease of the Premises does not include the right to use the roof (except as otherwise expressly provided in this Section 2.1 and Article XXVI of this Lease), mechanical rooms, electrical closets, janitorial closets, telephone rooms, or other non-common or non-public areas of the Building which are not included within the Premises. Tenant accepts the Premises “as is”, except for any improvements to be performed by Landlord pursuant to the Work Agreement, attached as Exhibit B . Tenant acknowledges that neither Landlord nor Landlord’s agent(s) have made any representations, expressed or implied, about the suitability of the Premises for Tenant’s intended use, except for general office use. It shall be Tenant’s sole responsibility, at Tenant’s sole time and expense, to obtain the necessary business licenses and occupancy permit for its Premises. Landlord and Tenant agree that as of the date of this Lease, the number of rentable square feet (i) in the Premises are the amounts set forth in Section 1.2 above, and (ii) in the Storage Space is 1,000, and such amounts are not subject to remeasurement absent a change in the configuration of space in the Building impacting the Premises or Storage Space.

     2.2 Unless otherwise allowed for and addressed in this Lease, Tenant may not enter or occupy the Premises until the Premises are tendered by Landlord. Because Tenant is performing the tenant improvement work (including the demolition work), Landlord shall use commercially reasonable efforts to deliver the Premises, on a floor-by-floor basis as soon as reasonably possible after a floor (or part of floor to the extent that less than an entire floor is part of the Premises) is vacated by an existing tenant. Any entry upon the Premises by Tenant before the Premises are tendered by Landlord shall only be with Landlord’s written consent and/or when accompanied by a representative of Landlord or Landlord’s representative (unless otherwise allowed for and addressed in this Lease). Said entry shall be subject to all of the terms of this Lease, but no such permitted entry shall change the Lease Commencement Date or the expiration date of the Lease Term.

ARTICLE III
TERM

     3.1 All of the provisions of this Lease shall be in full force and effect from and after the date first above written. The Lease Term shall commence on the Lease Commencement Date specified in Section 3.2 . If the Lease Commencement Date is not the first day of a month, then the Lease Term shall be the period set forth in Section 1.3 plus the partial month in which the Lease Commencement Date occurs. The Lease Term shall also include any properly exercised renewal or extension of the term of this Lease. In addition, the initial Lease Term may automatically be extended in accordance with the terms of Section 3.2(h) below.

     3.2 (a) The “ Lease Commencement Date ” shall be the earlier to occur of: (a) the date Tenant commences beneficial occupancy of a material portion of the Premises; and (b) November 8, 2007, provided, however, if Landlord does not deliver substantially all of the Premises to Tenant in the condition required by the terms of this Lease on or before the Anticipated Delivery Date, then the foregoing date of November 8, 2007 will be extended on a day-for-day basis for each day after the Anticipated Delivery Date until Landlord delivers substantially all of the Premises to Tenant in the condition required by the terms of this Lease. As used herein, Landlord’s delivery of “substantially all of the Premises” shall mean that Landlord has delivered substantially all of the square footage of the Premises (other than de minimus portions of the Premises, the failure to deliver which does not interfere with Tenant’s access to or beneficial occupancy of the Premises, Tenant’s construction schedule, Tenant’s cost to initially fit-out the Premises or commencement of Tenant’s Work). It is presently anticipated that the Premises will be delivered to Tenant on or about the Anticipated Delivery Date; provided, however, that if Landlord does not deliver possession of the Premises or any portion thereof by such date, Landlord shall not, except as expressly set forth to the contrary in this Section 3.2 below, have any liability whatsoever and this Lease shall not be rendered void or voidable, as a result thereof. Tenant will be deemed to have commenced beneficial occupancy of

the Premises when Tenant conducts business in or occupies twenty-five percent (25%) or more the Premises. Promptly after the Lease Commencement Date is ascertained, Landlord and Tenant shall execute the certificate confirming the Lease Commencement Date attached to this Lease as Exhibit D .

          (b) If Landlord has not delivered the portion of the Premises consisting of floors 6, 7 & 8 (each a “ Floor ” and collectively, the “ Floors ”) to Tenant on or before May 1, 2007, vacant from any other tenancy and with all personal property removed on such date (the “ Ready Condition ”), Tenant shall become entitled to a monthly (based on calendar months) rent abatement equal to One Hundred Thousand Dollars ($100,000) for the calendar month of May 2007 (the “ Upper Floors Abatement Credit ”). If the Floors are not delivered to Tenant in the Ready Condition on or before June 1, 2007, then the Upper Floors Abatement Credit will be increased by the sum of One Hundred Fifty Thousand Dollars ($150,000) for the calendar month of June 2007 to an aggregate amount of Two Hundred Fifty Thousand Dollars ($250,000). If the Floors are not delivered to Tenant in the Ready Condition on or before the first calendar day of July 2007 or on or before the first day of any subsequent calendar month thereafter, the Upper Floors Abatement Credit will be increased by the sum of Two Hundred Thousand Dollars ($200,000) per calendar month for the calendar month of July and each subsequent calendar month thereafter.

               (1) By way of example only of the foregoing terms of Subsection (b) above, if Landlord delivers the Floors to Tenant in the Ready Condition on August 1, 2007, the Upper Floors Abatement Credit will be the sum of Four Hundred Fifty Thousand Dollars ($450,000).

               (2) Notwithstanding the foregoing terms of this Section 3.2 , (i) if Landlord delivers any Floor to Tenant (but less than all of the Floors) and if, and only if, all of the Floors are delivered within three (3) weeks of the first delivery of a Floor to Tenant, the Upper Floors Abatement Credit will be reduced on a pro rata basis (based on the rentable square footage of the Floors) for the applicable Floor(s) delivered from the date of delivery, and (ii) upon delivery of the Floors (or the last Floor, in the event delivery of the Floors is staggered on a floor by floor basis), the Upper Floors Abatement Credit will be prorated based on the number of days in the applicable calendar month of delivery. By way of example only of the foregoing terms of Subsection (b), if Landlord delivers the Floors to Tenant in the Ready Condition on June 10, 2007, the Upper Floors Abatement Credit will equal the sum of One Hundred Fifty Thousand Dollars ($150,000) (which sum is made up of $100,000 for the calendar month of May and $5,000 per day in the ten (10) days in the calendar month of June (i.e., for the calendar month of June the total scheduled abatement of $150,000 divided by 30 days is $5,000 per day).

               (3) Any such phased delivery of a Floor and resultant pro rata abatement reduction shall not modify the Lease Commencement Date. Landlord shall not deliver, and Tenant shall not be obligated to accept, any partial floors that comprise the Floors. Tenant shall, however, accept an entire floor so long as such floor is delivered in Ready Condition.

               (4) Within five (5) business days after the end of each calendar month in which a portion of the Upper Floors Abatement Credit may accrue, Landlord shall pay such accrued amount into escrow in accordance with the terms hereof. If Tenant properly and timely terminates this Lease in accordance with the terms of Subsection 3.2(i) below, then upon the effectiveness of Tenant’s termination, the Upper Floors Abatement Credit through the date of termination will be released from escrow and delivered to Tenant, and Landlord shall pay Tenant the portion of the balance of Upper Floors Abatement Credit which has accrued for the final (partial) month but which was not placed in escrow. However, if at any time Landlord delivers all Floors to Tenant, the Upper Floors Abatement Credit will be released from escrow and delivered to Landlord. All interest earned on the escrowed amounts will follow such amounts and be delivered to the applicable party. The Upper Floors Abatement Credit will be held by an escrow agent designated by Tenant and reasonably acceptable to Landlord; Landlord hereby approving Commonwealth Land Title Insurance Company (c/o LandAmerica Commercial Services) as the escrow agent. Any fees charged by the escrow agent will be paid by Landlord. All sums held in escrow pursuant to the terms hereof will be governed by the terms of the escrow agreement attached hereto as Exhibit M , which escrow agreement will be executed and delivered by Landlord, Tenant and the escrow agent concurrently with the execution and delivery of this Lease. Landlord’s lender may be an intended third party beneficiary of the escrow agreement

and have a security interest in the escrow, provided that, Landlord’s lender agrees to be bound by the obligations of Landlord pursuant to the terms of this Subsection if Landlord’s lender succeeds to Landlord’s interest in the Building. Tenant shall not grant a security interest in the escrow, and Tenant shall not assign or otherwise transfer any interest in the escrow (except to a Permitted Transferee that assumes all of Tenant’s obligations under this Lease in accordance with the terms of this Lease).

               (5) If Tenant properly and timely exercises its right of termination in accordance with the terms of Subsection 3.2(i) below, then (a) within thirty (30) days after receipt of reasonably detailed invoices, Landlord shall reimburse Tenant for Tenant’s out-of-pocket hard cost expenses (if any) incurred in the performance of any demolition work through the date of termination, and (b) within thirty (30) days after receipt of reasonably detailed invoices, Landlord shall reimburse Tenant for fifty percent (50% ) of Tenant’s third party out-of-pocket expenses ( e.g. , architectural and legal costs) incurred in preparing to occupy the Premises and negotiate the Lease; provided, however, that Landlord’s obligation to reimburse Tenant for such third party expenses pursuant to subpart (b) above shall not exceed $200,000 (i.e., for $400,000.00 or more of such expenses).

               (6) If Tenant properly and timely terminates this Lease in accordance with the terms of this Section 3.2(i) below, then other than (i) Landlord’s payment of the Upper Floors Abatement Credit to Tenant in accordance with the terms of Subsection (4) above, (ii) Landlord’s payment (or reimbursement, as applicable) of the amounts expressly set forth in Subsection (5) immediately above, and (iii) Landlord’s return of the Security Deposit to Tenant, Landlord shall not pay or be obligated to pay any additional amounts to Tenant.

          (c) If Landlord has not delivered the First Floor Space in Ready Condition by June 1, 2007, Tenant shall become entitled to a rent abatement (the “ First Floor Abatement ”) (in addition to any other rent abatements set forth in this Section 3.2 ) until the First Floor Space is delivered to Tenant in the Ready Condition. The First Floor Abatement is equal to the per day amount of Premises Base Rent applicable to the First Floor Premises during the first Lease Year ($701.79) for every two days after June 1, 2007, that Landlord delivers the First Floor Space in the Ready Condition.

               (1) By way of example only of the foregoing terms of Subparagraph (c), if Landlord delivers the First Floor Space in the Ready Condition on June 20, 2007, the First Floor Abatement will be $7,017.90, which is the product of $701.79 multiplied by 10 days (i.e., the period of June 1 to June 20 based on the one-for-two applicability).

          (d) Tenant represents and warrants that (i) the term of its lease for space at 1899 L Street (“ Tenant’s Existing Lease ”) will end on January 31, 2008 (subject to a right to extend the term thereof for up to an additional eleven (11) months, and that Tenant leases approximately 72,727 rentable square feet under Tenant’s Existing Lease and (ii) Tenant has not entered into any lease of space in the Washington, D.C. metropolitan area other than Tenant’s Existing Lease. If Tenant at any time prior to delivery of the Floors to Tenant in the Ready Condition either (x) exercises its right to extend the term of Tenant’s Existing Lease, or (y) enters into one (1) or more swing-space leases of space in the metropolitan area of Washington, D.C. (either (x) or (y), a “ Swing/Extension Lease ”), Tenant shall deliver written a notice to Landlord within five (5) business days of entering into such agreement or exercise of such right certifying that it has entered into a Swing/Extension Lease, along with a reasonable summary of the terms of the Swing/Extension. If Tenant timely enters into a Swing/Extension Lease in accordance with the foregoing terms of this Subsection (d) and sends such certification to Landlord as provided above, Tenant shall become entitled to a rent abatement (the “ Swing/Extension Abatement ”) (in addition to any other rent abatements set forth in this Section 3.2 ). The Swing/Extension Abatement is equal to one day of Premises Base Rent (expressly excluding Annual Storage Space Base Rent) during the first Lease Year (i.e., $45.75 per rentable square foot) applicable to Premises on the date of this Lease for every two (2) days that the Lease Commencement Date occurs before the expiration of the Swing/Extension Lease; provided, however, the Swing/Extension Abatement will not be applicable to more than eight (8) months of extended term or swing space (i.e., four (4) months of abatement by virtue of the one-for-two applicability of such abatement) regardless of the actual expiration of the Swing/Extension Lease, as the case may be. Notwithstanding the foregoing terms of this Subsection (d), to the extent that the rentable square footage of the Swing/Extension Lease (the “ Swing/Extension Square Footage ”) is for fewer rentable square feet than the rentable square

footage under Tenant’s Existing Lease (the “ Existing Square Footage ”), then the Swing/Extension Abatement shall be proportionately reduced based on the amount by which the Swing/Extension Square Footage is less than the Existing Square Footage (but in no event will the Swing/Extension Abatement be increased if the Swing/Extension Square Footage is greater than the rentable square footage under Tenant’s Existing Lease).

               (1) By way of example only of the foregoing terms of Subparagraph (d), if Tenant enters into the Swing/Extension Lease and the Swing/Extension Lease expires on February 28, 2008, the Lease Commencement Date occurs on November 1, 2007, and the actual number of rentable square feet in the Premises as of the date of the Lease is 93,300, then the Swing/Extension Abatement would equal the sum of Seven Hundred One Thousand Six Hundred Sixty-Seven and 00/100 Dollars ($701,667.00), which amount is equal to the daily Premises Base Rent of $11,694.45 multiplied by 60 days (which 60 days represents the one-for-two applicability of the 120 days between (and including) November 1 and February 28.

          (e) To the extent that Tenant becomes entitled under the terms of this Lease to any of the Upper Floors Abatement Credit, the First Floor Abatement and/or the Swing/Extension Abatement, then any such applicable abatements to which Tenant is entitled are together the “ Delay Abatement Credits ”. If Tenant is entitled to Delay Abatement Credits, then all such abatements will be applied to the first rents due Landlord under the Lease.

          (f) Except for the amounts expressly set forth in Subsection (d) immediately above, Landlord will have no responsibility whatsoever to share or pay ongoing holdover and related costs incurred by Tenant.

          (g) At any time in this Section 3.2 that a rent abatement is calculated based on one day for every two days, if (on a fractional basis) the number of days resulting from such calculation is not a whole number, such fraction of a number shall be rounded to the next lowest whole number. By way of example, if a rent abatement is based on a two-for-one applicability and the (aggregate) applicable number of days is sixty-one (61), then the rent abatement will be based on thirty (30) days. If any rent abatement in this Section 3.2 is based on base rent payable under the terms of this Lease, then unless expressly set forth to the contrary, such base rent will only apply to the Premises Base Rent (i.e., base rent payable for rentable square feet in the Premises) and specifically excludes base rent payable for the Storage Space.

          (h) If Tenant becomes entitled to a Delay Abatement Credit, then the initial term of the Lease will automatically be extended for a period of time (the “ Abatement Extension Period ”). The Abatement Extension Period is equal to the quotient (which quotient will be equal to a number of days) of (i) the Delay Abatement Credits multiplied by two (2), divided by (ii) the daily Premises Base Rent for the Premises during the tenth Lease Year . If such quotient is not a whole number, then such number (i.e., the number of days) will be increased to the next whole number. However, if Tenant timely and properly terminates this Lease in accordance with the terms of Article XXX , then the Abatement Extension Period will not be applicable, and instead, Tenant shall pay the Termination Payment in accordance with the terms of Article XXX .

               (1) By way of example only of the foregoing terms of Subsection (h) above, if the Delay Abatement Credits were $500,000 and the daily Premises Base Rent for the Premises during the tenth Lease year is $14,117.70, then the initial Lease Term will be extended by seventy-one (71) days, which is quotient of $1,000,000 (i.e., the Delay Abatement Credits multiplied by two (2)), divided by $14,117.70 (and rounded up to the next whole number).

               (2) If the initial Lease Term is extended in accordance with the terms of Subsection (h), then (i) the Base Rent payable by Tenant during the Abatement Extension Period will be the Base Rent payable in the tenth Lease Year, and (ii) Tenant’s payment of Operating Expenses and Real Estate Taxes (hereinafter defined) will be calculated as if the Abatement Extension Period were in the eleventh Lease Year (and the Lease Term was extended into the eleventh Lease Year).

          (i) If Landlord has not delivered the Floors in Ready Condition on or before July 15, 2007 (the “ Outside Delivery Date ”), then Tenant will have a one-time option, exercisable by delivery of written notice between the period of July 15, 2007 until 5:00 p.m.

(eastern time) on September 30, 2007, to terminate the Lease, provided that if at any time Landlord delivers the Floors prior to Tenant properly exercising such termination option or if at any time Tenant commences beneficial occupancy of the Floors, such termination option will automatically lapse, terminate and be of no further force and effect. Notwithstanding the foregoing termination right set forth in this Subsection (i), if Landlord within thirty (30) days (the “ Cure Period ”) of receipt of Tenant’s termination notice delivers the Floors in Ready Condition, Tenant shall accept the Floors and its termination will not be effective, provided that if at any time during the Cure Period Landlord delivers notice to Tenant that it is unable to deliver the Floors, Tenant’s termination will be effective as of the date of receipt of such notice from Landlord. If Landlord does not deliver the Floors in Ready Condition during the Cure Period and no such notice is delivered by Landlord during the Cure Period, such termination will be effective as of the date of expiration of the Cure Period. If Tenant fails to exercise its termination option on or before 5:00 (eastern time) on September 30, 2007, Tenant’s termination option set forth in this Subsection (i) will automatically lapse, terminate and be of no further force and effect. Provided Landlord has not delivered written notice of termination in accordance with the terms of this Subsection, at all times (including, but not limited to, during the period following the expiration of any termination right provided to Tenant pursuant to this proposal), Landlord shall use all commercially reasonable efforts to deliver the Premises, provided that in no event will Landlord be obligated to institute a suit or action to evict the government agency currently occupying any Floor. “ Lease Year ” shall mean a period of twelve (12) consecutive months commencing on the Lease Commencement Date, and each successive twelve (12) month period thereafter; provided, however, that if the Lease Commencement Date is not the first day of a month, then the second Lease Year shall commence on the first day of the month after the month in which the Lease Commencement Date occurs, and the Base Rent for any partial additional month during the first Lease Year will be the Monthly Base Rent for the first Lease Year prorated based on the actual number of days in such month. Notwithstanding the provisions of Article XXX of this Lease to the contrary, no termination fee shall be payable by Tenant in the event Tenant terminates the Lease pursuant to the provisions of this Section 3.3 .

ARTICLE IV
BASE RENT

     4.1 (a) From and after the Lease Commencement Date, Tenant shall pay the Base Rent for the entire Premises in equal monthly installments in advance on the first day of each month during a Lease Year. For the purpose of this Lease, the term “ Base Rent ” means the Premises Base Rent, which includes the Annual Base Rent specified in Article I and the Storage Space Base Rent specified in Article I , which includes the Annual Storage Space Base Rent, plus any additional amounts of annual base rent for which Tenant is obligated to pay under the terms of this Lease. For the purpose of this Lease, the term “ Monthly Base Rent ”, or “ monthly Base Rent ” or “ monthly installment of Base Rent ” means the amounts specified in Article I of this Lease, or one-twelfth (1/12) of the applicable Base Rent during the applicable Lease Year.

          (b) Notwithstanding anything to the contrary contained in this Article IV and provided no Event of Default (hereinafter defined) is continuing under this Lease, Landlord hereby agrees to grant Tenant an abatement of one hundred percent (100%) of the Monthly Base Rent payable under this Lease for (a) the first four (4) full calendar months of the first Lease Year, and (b) the first two (2) full calendar months of the second Lease Year. Other than as set forth in the preceding sentence and in Section 3.2 of this Lease, Tenant shall pay the full amount of Base Rent due in accordance with the provisions of this Article IV .

     4.2 If the Lease Commencement Date is not the first day of a month, then the Base Rent from the Lease Commencement Date until the first day of the following month shall be prorated on a per diem basis based on the actual number of days in such month, and Tenant shall pay such prorated installment of the Base Rent on the Lease Commencement Date.

     4.3 Tenant shall pay to Landlord, at the same time as each monthly installment of Base Rent, an amount equal to the monthly installment of Storage Space Rent as defined in Section 1.5(b) . For the purpose of confirming Landlord’s rights and remedies under the terms of this Lease and Tenant’s obligation to pay such amount, each monthly installment of Storage Space Rent will be deemed to be “ Base Rent ” (even though the Storage Space Rent will be in addition to Base Rent).

     4.4 All sums payable by Tenant under this Lease, whether or not stated to be Base Rent, additional rent or otherwise, shall be paid to Landlord by wire transfer, without setoff, deduction or demand, to the Landlord Payment Account, or to such other party, by check or such other account as Landlord may designate in writing. Landlord’s acceptance of rent after it shall have become due and payable shall not excuse a delay upon any subsequent occasion or constitute a waiver of any of Landlord’s rights under this Lease.

ARTICLE V
OPERATING EXPENSES AND REAL ESTATE TAXES

     5.1 (a) During the Lease Term, Tenant shall pay Landlord, as additional rent for the Premises, (i) Tenant’s proportionate share (which, as of the date of this Lease, is 38.44% based on Tenant’s lease of One Hundred Eleven Thousand Eight Hundred Ninety-Five (111,895) square feet of rentable area) of the amount by which Operating Expenses incurred by Landlord for each calendar year falling entirely or partly within the Lease Term exceed a base amount (the “ Base Year Operating Expenses ”) equal to the Operating Expenses incurred by Landlord during the twelve month period (the “ Base Year ”) commencing January 1, 2008, and ending December 31, 2008, and (ii) Tenant’s proportionate share (which, as of the date of this Lease, is 38.44% based on Tenant’s lease of One Hundred Eleven Thousand Eight Hundred Ninety-Five (111,895)) of the amount by which Real Estate Taxes (as defined in Section 5.1(c) ) for each calendar year falling entirely or partly within the Lease Term exceed a base amount (the “ Base Year Real Estate Taxes ”) equal to the Real Estate Taxes incurred by Landlord during the Base Year. To the extent that the aggregate of the Operating Expenses and Real Estate Taxes for any calendar year are less than the aggregate of the Base Year Operating Expenses and Base Year Real Estate Taxes, then Tenant shall only be responsible for the net increase over the aggregate of the Base Year Operating Expenses and the Base Year Real Estate Taxes after deducting the amount of such reduction from the Base Year Operating Expenses and/or Base Year Real Estate Taxes (as applicable); provided, however, in no event will the netting-out of increase in taxes and expenses pursuant to this sentence result in a credit or reimbursement to Tenant. By way of hypothetical example of the foregoing sentence only, if the Base Year Operating Expenses were $100 and the Base Year Real Estate Taxes were $100 and thereafter in a calendar year in which Real Estate Taxes are $110 and Operating Expenses are $90, Tenant’s responsibility for (its proportionate share) of such costs would be $0. For purposes of this Article V , Tenant’s proportionate share of such increases in Operating Expenses shall be that percentage which is equal to a fraction, the numerator of which is the number of square feet of rentable area in the Premises from time to time and the denominator of which is the total number of square feet of rentable area in the Building from time to time, excluding the number of square feet devoted to storage space located in the Building, the Storage Space and the Building’s parking garage (the “ Garage ”), and Tenant’s proportionate share of such increases in Real Estate Taxes shall be that percentage which is equal to a fraction, the numerator of which is the number of square feet of rentable area in the Premises from time to time and the denominator of which is the total number of square feet of rentable area in the Building from time to time, excluding the number of square feet devoted to storage space located in the Building, the Storage Space and the Garage. It is understood that (x) the number comprising such numerator is subject to change in the event Tenant exercises its right to expand the Premises under Article XXVIII hereof, or if Landlord exercises its right to recapture a portion of the Premises pursuant to Section 8.4 hereof, so that Tenant actually pays its fair share of Operating Expenses and Real Estate Taxes, and (y) the number comprising such denominator is subject to change because of changes in the use or configuration of space in the Building or the addition of space to the Building or the deletion of space from the Building or in the amount of space leased by tenants who pay by separate meter for their electrical and/or janitorial, cleaning, or other utilities or services so that Tenant actually pays its fair share of Operating Expenses and Real Estate Taxes; provided, however, that any such change in rentable area shall be determined in accordance with the standard set forth in Section 25.17 of this Lease, and, in any event, that the denominator with respect to Real Estate Taxes shall be calculated based on the total number of square feet of rentable area in the Building, exclusive of the Garage, any storage areas located in the Building and any Storage Space leased by Tenant. Notwithstanding the foregoing, in no event shall the aforementioned denominator be decreased by more than five thousand (5,000) square feet of rentable area in the aggregate during the Lease Term (as the same may be extended pursuant to the terms hereof). Tenant’s proportionate share shall be proportionately increased in the event Tenant expands the Premises in accordance with the terms of this Lease during the Lease Term (exclusive of any additional

Storage Space leased by Tenant). Tenant’s proportionate share shall be proportionately decreased in the event the size of the Premises is reduced in accordance with the terms of this Lease during the Lease Term.

          (b) Operating Expenses shall be defined as the following costs and expenses relating to the management and operation of the Building using generally accepted accounting principles consistently applied: (1) electricity, gas, water, HVAC (as defined below), sewer and other utility charges of every type and nature; (2) premiums and other charges for insurance and deductibles under such insurance policies; (3) personnel costs for employees of Landlord engaged full time in the operation, management, maintenance and repair of the Building and Landlord’s reasonable allocation of the wages, salary or other compensation or benefits paid to the individual employees of Landlord and Landlord’s Building manager, if offsite, who are assigned part-time to the operation, management, maintenance and repair of the Building, and the cost of Landlord’s property manager for the Building, provided that in no event shall the management fee for Landlord’s property manager for the Building exceed three percent (3%) per annum of the gross income of the Building (with Landlord hereby confirming that the management fee for the Base Year shall be three percent (3%) of the gross annual income of the Building for the Base Year (subject to the provisions of Section 5.1(d) below); (4) costs of service and maintenance contracts relating to the Building as a whole (excluding contracts for the operation of the Garage); (5) maintenance, repair and supplies, and to the extent permitted to be passed through as an Operating Expense hereunder, replacement expenses, which are deducted by Landlord in computing its federal income tax liability; (6) depreciation (on a straight-line basis) for capital expenditures made by Landlord to reduce Operating Expenses (provided such annual depreciation does not exceed the annual savings by Landlord) or to comply with legal or insurance requirements applicable to the Building after the date hereof, such capital costs to be amortized over Landlord’s reasonable estimated useful life of the improvement, together with interest at the rate paid by Landlord on any funds borrowed for such expenditures; (7) charges for the following services: lobby attendant(s), if any, concierge, if any, at least one (1) security guard on a 24-hour, seven-days-a-week basis and access control; and other services or amenities provided to the Building provided, however, if a service or amenity is not provided in the Base Year but is provided in a subsequent Lease Year, Landlord shall pass through only the cost of such service or amenity in excess of Landlord’s reasonable estimate of what the cost of such service or amenity would have been in the Base Year if such service or amenity had been provided in the Base Year; (8) charges for janitorial, trash removal and cleaning services and supplies furnished to the Building; (9) costs of snow removal; (10) costs associated with the operation, maintenance, equipping and repair of the Building’s fitness center (the “ Fitness Center ”) (but specifically excluding the costs of initially equipping of the Fitness Center in accordance with the terms of this Lease, which initial equipping costs will not be an Operating Expense); and (11) any other expense reasonably incurred by Landlord in maintaining, repairing, operating or cleaning the Building. Operating Expenses shall not include: (i) Real Estate Taxes; (ii) principal or interest payments on any Mortgages (as defined in Section 21.1 ); (ii) costs which are solely attributable to any retail portions of the Building; (iii) costs for which Landlord is actually reimbursed by Tenant, by insurance proceeds or by other tenants of the Building (other than such tenants’ regular contributions to Operating Expenses); (iv) legal fees incurred for negotiating leases or collecting rent; (v) costs directly and solely related to maintenance and operation of the entity that constitutes Landlord, such as accounting fees incurred solely for the purpose of reporting Landlord’s financial condition; (vi) costs of repairs, replacements or other work occasioned by fire, windstorm or other casualty, or the exercise by governmental authorities of the right of eminent domain (except the deductible), whether such taking be total or partial, to the extent of any condemnation awards received by Landlord; (vii) leasing commissions, attorneys’ fees, marketing costs, disbursements and other expenses incurred by Landlord or its agents in connection with negotiations for leases with tenants, other occupants or prospective tenants or other occupants of the Building; (viii) tenant allowances, tenant concessions and other costs and expenses (including permit, license and inspection fees) incurred in connection with completing, fixturing, furnishing, renovating or otherwise improving, decorating or decorated leased premises for tenants or other occupants of the Building, or vacant, leaseable space in the Building, including the cost of space planning/interior architecture fees and/or engineering costs for the same; (ix) fees, fines or penalties (including legal fees) incurred due to the violation (as compared to compliance costs, which are included in Operating Expenses as provided above) by Landlord, its agents, any tenant (other than Tenant) or other occupant of the Building, and/or of any valid applicable Laws that would not have been incurred but for such violation by Landlord, its agent, tenant or other occupant, it being intended

that each such party shall be responsible for the costs resulting from its violation of such leases and Laws; (x) penalties for any late payment by Landlord, including, without limitation, taxes; (xi) compensation paid to clerks, attendants or other persons in commercial concessions (such as a snack bar, restaurant or newsstand, but not including the Building amenities such as the Fitness Center or the parking facilities); (xii) costs of correcting defects in the construction of the Building; (xiii) costs of services (including electricity), items or other benefits of a material type which are not available to Tenant without specific charge therefor, but which are provided to another tenant or occupant of the Building, whether or not such other tenant or occupant is specifically charged therefor by Landlord; (xiv) depreciation/amortization for capital expenditures, except to the extent expressly permitted above; (xv) costs arising from the presence of Hazardous Materials (hereinafter defined) in, about or below the Land or the Building (including any Hazardous Materials brought to, deposited on or dispossessed of at the Building by Landlord or Landlord’s contractors, agents or employees, but specifically excluding any Hazardous Materials brought in, about or below the Land by Tenant or Tenant’s contractors, agents, employees or invitees); (xvi) the costs of special services and utilities separately paid by particular tenants of the Building; (xvii) advertising for vacant space in the Building; (xviii) compensation paid to officers or executives of Landlord above the level of property manager and costs and salaries associated with Landlord’s home office or off-site employees, except to the extent expressly permitted above; (xix) costs incurred as the result of Landlord’s tortious or grossly negligent conduct; (xxi) costs directly incurred in connection with the sale, financing or refinancing, mortgaging, selling or change of ownership of the Building, including attorneys’ fees and accountants’ fees attributable thereto, closing costs, title insurance premiums and transfer taxes; (xxiii) rentals and other related expenses incurred in leasing equipment ordinarily considered to be of a capital nature, except on a temporary basis and except to the extent such capital expenditures would otherwise be includable as an Operating Expense as provided above; (xxiv) amounts which would otherwise be included as Operating Expenses which are paid to any affiliate or subsidiaries of Landlord to the extent the costs of such services exceed the fair market value; (xxv) costs incurred (less costs of recovery) for any items to the extent reimbursed to Landlord under a manufacturer’s, materialman’s, vendor’s or contractor’s warranty; (xxvi) contributions to charitable organizations; (xxvii) costs of acquiring, installing, moving or restoring objects of art; (xxviii) costs incurred in removing the property of former tenants or other occupants in the Building; (xxix) expenses attributable to Landlord’s use of any public portions of the Building including, but not limited, to shows, promotions, kiosks and advertising; (xxx) costs of special services to the Building that are not used by Tenant.

          (c) “ Real Estate Taxes ” shall mean (i) all real estate taxes and other impositions, including general and special assessments, arena taxes, and other similar taxes and assessments if any, which are imposed upon Landlord or assessed against the Building or the Land upon which the Building is located (the “ Land ”); (ii) any other present or future taxes or governmental charges that are imposed upon Landlord or assessed against the Building or the Land, including, but not limited to, any tax levied on or measured by the rents payable by tenants of the Building, which are in the nature of, or in substitution for, real estate taxes; (iii) all taxes which are imposed upon Landlord, and which are assessed against the value of any improvements to the Premises made by Tenant or any machinery, equipment, fixtures or other personal property of Tenant used therein; (iv) any rental or other charges or fees imposed upon Landlord in connection with the lease or use of any vault space(s); (v) any taxes or other charges levied pursuant to the Business Improvement Districts Act of 1996 or any amendments thereto or any similar business improvement district taxes; (vi) reasonable expenses (including attorneys’ fees) incurred in appealing a reduction or abatement of Real Estate Taxes; (vii) any taxes, charges or fees imposed upon Landlord in connection with the development, financing, construction, operation, maintenance and/or use of any major league baseball stadium and/or other sports complex in the District of Columbia (“ Stadium Taxes ”), but only if and to the extent such Stadium Taxes, charges or fees are not includable as Operating Expenses pursuant to this Article V ; provided, however, if Tenant is individually and separately assessed Stadium Taxes by the applicable governmental authority and actually pays Stadium Taxes and provides reasonably prompt written evidence of such payment to Landlord from time to time, then Tenant shall only pay as a pass-through under the term of this Lease the amount of Stadium Taxes that are imposed on Landlord that exceed, on a pro-rata basis, the amount of Stadium Taxes actually paid by Tenant (therefore, by way of example only, if Stadium Taxes are imposed on Landlord in the amount of $1,000, Stadium Taxes are imposed on Tenant in the amount of $100 and Tenant’s proportionate share of Real Estate Taxes is hypothetically 30%, then Tenant would be responsible for $200 of such Stadium Tax imposed on Landlord); and (viii) any business,

professional and occupational license tax payable by Landlord with respect to the Building. Real Estate Taxes shall not include any income taxes, excess profits taxes, excise taxes, franchise taxes, estate taxes, succession taxes and transfer taxes, except to the extent any of such taxes are in substitution for or recharacterization or replacement of Real Estate Taxes. If Landlord contests the Real Estate Taxes for any calendar year, and such contest results in either an increase in Real Estate Taxes for such calendar year or a decrease in the Base Year Real Estate Taxes, as applicable, then Landlord shall have the right to bill Tenant for all periods applicable to the Lease Term (even if such determination is made after the Lease Term), within sixty (60) days of Landlord’s receiving notice of such increase, for prior underpayments of Real Estate Taxes thereby resulting. In the event such contest results in either an increase in the Base Year Real Estate Taxes or a decrease in the Real Estate Taxes for any subsequent calendar year during the Lease Term, then Tenant shall deduct the net overpayment from its next payment of Base Rent due, or, in the event such contest is finalized after the Lease Term has expired but relates to any calendar years during the Lease Term, Landlord shall pay Tenant the net overpayment (after deducting therefrom any amounts then due from Tenant to Landlord) within thirty (30) days following the determination of the amount of such increase or decrease in the Real Estate Taxes.

          (d) In the event the average occupancy rate for the entire Building shall be less than one hundred percent (100%) or if any tenant is paying separately for electricity or other utilities or services for any calendar year, including the Base Year, for purposes of calculating the additional rent payable by Tenant pursuant to this Article V for each calendar year, the Operating Expenses and Real Estate Taxes for the Base Year and such calendar year shall each be increased by the amount of additional costs and expenses and Real Estate Taxes that Landlord reasonably estimates would have been incurred if the average occupancy rate for the entire Building had been one hundred percent (100%) and as if no tenants had separately paid for electricity or other utilities and services for the Base Year and such calendar year. It is the intent of this provision to permit Landlord to recover from Tenant its proportionate share of increases in Operating Expenses and Real Estate Taxes attributable to occupied space in the Building even though the aggregate of such expenses shall have been reduced as a result of vacancies in the Building.

          (e) On or about the first day of the calendar year after the Base Year, and at the beginning of each calendar year thereafter during the Lease Term, Landlord shall submit to Tenant a statement setting forth Landlord’s reasonable estimate of (a) the amount by which the Operating Expenses that are expected to be incurred during such calendar year will exceed the Base Year Operating Expenses, and (b) the computation of Tenant’s proportionate share of such anticipated increase in Operating Expenses. Except as otherwise provided in this Lease, Tenant shall pay to Landlord on the first day of each month following receipt of such statement during such calendar year an amount equal to Tenant’s proportionate share of the anticipated increases in such Operating Expenses multiplied by a fraction, the numerator of which is 1, and the denominator of which is the number of months during such calendar year which fall entirely or partly within the Lease Term and follow the date of the foregoing statement. Within one hundred twenty (120) days after the expiration of each calendar year falling entirely or partly within the Lease Term, Landlord shall submit to Tenant a statement showing (i) the actual amount of Base Year Operating Expenses and Base Year Real Estate Taxes; (ii) the actual Operating Expenses paid or incurred by Landlord and the actual Base Year Real Estate Taxes assessed against Landlord or the Building during the immediately preceding calendar year, (iii) a computation of Tenant’s proportionate share of the amount by which the Operating Expenses actually incurred during the preceding calendar year exceeded the Base Year Operating Expenses and a computation of Tenant’s proportionate share of the amount by which the Real Estate Taxes assessed for the preceding calendar year exceed the Base Year Real Estate Taxes, respectively, and (iv) the aggregate amount of the estimated payments made by Tenant on account of such Operating Expenses and the aggregate amount of the estimated payments made by Tenant on account of such Real Estate Taxes. If the aggregate amount of such estimated payments for Operating Expenses exceeds Tenant’s actual liability for such increases in Operating Expenses, or if the aggregate amount of such estimated payments for Real Estate Taxes exceeds Tenant’s actual liability for such Real Estate Taxes then Tenant shall deduct the net overpayment from the next payment of Base Rent due and owing by Tenant, or, in the case of the reconciliation for the calendar year in which the Lease Term expires, Landlord shall pay Tenant the net overpayment (after deducting therefrom any amounts then due from Tenant to Landlord), within thirty (30) days following the determination of the amount of the excess. If Tenant’s actual liability for such increases exceeds the estimated payments made by Tenant on account thereof, then Tenant

shall promptly pay to Landlord the total amount of such deficiency as additional rent due under this Lease. The foregoing provisions of this Section 5.1(e) shall, in all events, be subject to the provisions of the second and third sentences of Section 5.1(a) above.

          (f) No more than two (2) times in any calendar year, if Tenant has questions regarding an expense statement provided by Landlord or reasonably believes that any expense statement includes charges that are not permitted pursuant to the provisions of this Lease or contains an error, then Tenant may provide Landlord with a written statement enumerating Tenant’s reasonable questions or Tenant’s reasonably detailed reasons for Tenant’s objections to such expense statement. In each such case, Landlord or Landlord’s property manager shall meet with Tenant to discuss such objections, and shall exercise commercially reasonable efforts to provide any reasonable back-up in Landlord or Landlord’s property manager’s possession in connection with such objection. For a period of one hundred eighty (180) days after Tenant’s receipt of such expense statement (other than the expense statement for the Base Year, in which case within the later to occur of (i) eighteen (18) months after Tenant’s receipt of such expense statement, or (ii) six (6) months after Tenant’s receipt of the expense statement for the year following the Base Year), Tenant, or an independent, certified public accountant who is hired by Tenant on a non-contingent fee basis, shall have the right, during normal business hours and after giving at least ten (10) days’ advance written notice to Landlord, to inspect and complete an audit of Landlord’s books and records relating to Operating Expenses for the calendar year being audited. Tenant shall (and shall cause its employees, agents and consultants to) keep the results of any such audit or audited statement strictly confidential; provided that Tenant shall have no liability to Landlord for the disclosure of such information by an employee, agent or consultant of Tenant provided that Tenant shall have adopted and implemented procedures to ensure the confidential nature of such information (e.g., notifying all employees, agents and consultants of the requirements to keep such information confidential pursuant to the terms of this Section 5.2(f) ). If it is ultimately determined that such audit shows that the amounts paid by Tenant to Landlord on account of increases in Operating Expenses or Real Estate Taxes exceed the amounts to which Landlord is entitled under this Lease, Landlord shall credit the amount of such excess toward the next monthly payments of Base Rent due under this Lease, or, in the event the Lease Term has already expired, then within sixty (60) days after the determination of such excess, Landlord shall pay to Tenant the net over payment (after deducting therefrom any amounts then due from Tenant to Landlord). If it is ultimately determined that such audit shows that the amounts paid by Tenant to Landlord on account of increases in Operating Expenses or Real Estate Taxes are less than the amounts to which Landlord is entitled under this Lease, Tenant shall pay the amount of any such deficiency to Landlord within thirty (30) days from the date of such determination. In addition, Landlord shall, if appropriate, make a corresponding adjustment to the Base Year Operating Expenses and Base Year Real Estate Taxes, and, if applicable readjust any one or more prior year’s reconciliations and payments by Tenant for any applicable line item for which Tenant was overcharged or undercharged. If it is ultimately determined from Tenant’s audit that the Tenant’s share of aggregate amount of Operating Expenses set forth in the applicable reconciliation statement or Tenant’s share of the aggregate amount of Real Estate Taxes, in either case, was overstated by more than five percent (5%) (each, a “ Qualifying Discrepancy ”), and Tenant has not previously audited the financial statement for either or both of (i) the calendar year immediately preceding the calendar year that was the subject of the audit showing the Qualifying Discrepancy (the “ Immediately Preceding Year ”), or (ii) the calendar year that immediately precedes the Immediately Preceding Year (the “ Second Preceding Year ”), then by written notice to Landlord within ten (10) days after the audit showing such Qualifying Discrepancy, Tenant shall have the right within ninety (90) days following the audit showing such Qualifying Discrepancy to audit of the applicable statement for either or both of the Immediately Preceding Year or the Second Preceding Year provided such years were not previously audited. All costs and expenses of any such audit or audited statement shall be paid by Tenant; provided, however, that if it is ultimately determined that the audit performed by Tenant shows a Qualifying Discrepancy, then Landlord shall reimburse Tenant for Tenant’s reasonable, out-of-pocket costs incurred in connection with such audit in an amount not to exceed fifteen thousand dollars ($15,000), which fifteen thousand dollar limitation will be increased by one and one-half percent (1.5%) each Lease Year during the Lease Term. If Tenant does not notify Landlord in writing of any objection to any statement within one hundred twenty (120) days after receipt thereof or it Tenant fails to complete any audit within ninety (90) days (or one hundred fifty (150) days solely with respect to an audit of the Base Year) after written notice of objection, then Tenant shall automatically and irrevocably be deemed to have waived such objection; provided, however, that such ninety (90) day period (or one hundred fifty (150)

day period with respect the Base Year), will automatically be extended on a day-for-day basis for delays caused by Landlord, provided further that before Landlord will be deemed to have delayed, Tenant shall have delivered a written notice to Landlord stating that Tenant is claiming a Landlord delay and the applicable extension to which it is entitled, and if at any time Tenant claims that Landlord has delayed more than five (5) business days (or an additional five (5) business day period), then before Landlord will be deemed to have further delayed, Tenant shall again deliver written notice of the applicable extension to which it is entitled. Landlord and Tenant acknowledge that the purpose of the immediately preceding notices is to ensure that Tenant does not claim it is entitled to extensions of more than five (5) business day increments without first providing notice to Landlord of each and every claim for an additional five (5) business day extension.

     5.2 In the event the Lease Term begins or expires on a day other than the first and last day of a calendar year, respectively, the increases in the Operating Expenses for such calendar year shall be apportioned by multiplying the amount of Tenant’s proportionate share thereof for the full calendar year by a fraction, the numerator of which is the number of days during such calendar year falling within the Lease Term, and the denominator of which is 365.

     5.3 Tenant’s liability for its proportionate share of the increases in Operating Expenses and Real Estate Taxes described in Article V of this Lease for the last calendar year falling entirely or partly within the Lease Term shall survive the expiration of the Lease Term. Similarly, Landlord’s obligation to refund to Tenant the excess, if any, of the amount of Tenant’s estimated payments on account of such Operating Expenses and Real Estate Tax increases for such last calendar year over Tenant’s actual liability therefor shall survive the expiration (or earlier termination) of the Lease Term.

     5.4 Notwithstanding anything to the contrary, in the event Landlord does not deliver the Premises to Tenant in the condition required under the terms of this Lease on or before December 31, 2007, then the Base Year shall be re-defined to be the twelve (12) month period commencing January 1, 2009, and ending December 31, 2009.

ARTICLE VI
SECURITY DEPOSIT

     6.1 On or before the dates set forth in Section 1.8 , Tenant shall either, at Tenant’s election, post a Letter of Credit (as defined below) or deliver cash to Landlord in an aggregate amount equal to Three Million Two Hundred Seventy-Six Thousand Three Hundred Seventy-Eight Dollars and Sixty-Three Cents ($3,276,378.63), as a security deposit (the “ Security Deposit ”), as such amount may be increased in accordance with the terms of this Lease. Solely for clarification, Landlord and Tenant acknowledge that the calculation of the foregoing Security Deposit is based on (i) eight (8) months of base rent on 94,004 rentable square feet (which is based on 35,432 rentable square feet on each of the 7 ^th and 8 ^th floors, 17,541 rentable square feet on the 6 ^th floor, and 5,599 rentable square feet on the first floor), and (ii) six months (6) of base rent on 17,891 rentable square feet on the 6 ^th floor, which latter subpart (ii) Landlord and Tenant further acknowledge is being treated (solely for the determination of the amount of the Security Deposit) as Tenant’s exercise of an expansion option because immediately prior to entering into the Lease, Tenant requested to expand the size of the Premises by such 17,891 rentable square feet. All cash which Tenant delivers to Landlord as a Security Deposit, will be deposited in an account maintained by Landlord (which account may also contain the security deposits of other tenants or other sums) and Landlord shall not pay Tenant any interest thereon, except as expressly required to the contrary by applicable law. If, pursuant to Tenant’s exercise of an expansion option or otherwise, the number of square feet of rentable area in the Premises should at any time increase above the amount of rentable square feet being leased by Tenant as of the date hereof, then the Security Deposit shall be increased by adding thereto an amount that is equal to six (6) months of the then current base rent for the additional rentable square footage leased by Tenant multiplied by a fraction, the numerator of which is the remaining Lease Years in the Lease Term (plus any fraction thereof) and the denominator of which is the total number of Lease Years in the Lease Term. If the Security Deposit is increased pursuant to any of the provisions of this Section 6.1 , then Tenant shall immediately deposit with Landlord an amount equal to the portion of the increased amount that would have been paid to Landlord as of such time if the increased amount had been part of the Security Deposit as of the date of this Lease, and any subsequent installments of the Security Deposit shall be adjusted accordingly. If, pursuant to Landlord’s exercise of its right to recapture space in accordance with the terms of

Article VIII , the number of square feet of rentable area in the Premises should decrease below the amount of rentable square feet being leased by Tenant as of the date immediately prior to such recapture, the Security Deposit shall be decreased pro rata based on the decrease in the rentable square footage leased by Tenant. If the Security Deposit is so decreased and the Security Deposit is the form of a letter of credit, such reduction shall occur by means of delivery by Tenant to Landlord of an amendment to the Letter of Credit reducing the amount thereof as directed by Landlord, or a substitute Letter of Credit in such amount and in strict conformity with the terms of this Article VI , in which latter event, the original Letter of Credit will be promptly returned to Tenant. The Security Deposit may be assigned by Landlord to the holder of any Mortgage, provided that the holder of such Mortgage has executed and delivered an SNDA (hereinafter defined) in accordance with the terms of Article XXI of this Lease.

          (a) The Security Deposit shall be security for the performance by Tenant of all of Tenant’s obligations, covenants, conditions and agreements under this Lease. Within sixty (60) days after the expiration of the Lease Term (or earlier termination by Tenant in accordance with the express terms of this Lease), and provided Tenant has vacated the Premises, Landlord shall return the Security Deposit to Tenant, less such portion thereof as Landlord shall have appropriated to satisfy any Event of Default by Tenant under this Lease; provided, however, if Tenant effectively terminates this Lease pursuant to the terms of Section 3.2(i) or Section 21.4 (and provided Tenant never occupied the Premises), Landlord shall return the Security Deposit to Tenant within five (5) business days after the effective date of such termination, less such portion thereof as Landlord shall have appropriated to satisfy any Event of Default by Tenant under this Lease, if any. In the event of an Event of Default by Tenant under this Lease, Landlord shall have the right, but shall not be obligated, to use, apply or retain all or any portion of the Security Deposit for (i) the payment of any Base Rent or additional rent or any other sum as to which Tenant is in default under this Lease beyond applicable notice and cure period, (ii) the payment of any amount which Landlord may spend or become obligated to spend to repair (after the expiration of any applicable notice and cure periods) physical damage to the Premises or the Building pursuant to Section 9.1 of this Lease, or (iii) other than the payment of Base Rent or additional rent or any other sum pursuant to clause (i) of this Section, the payment of any amount Landlord may spend or become obligated to spend, or for the compensation of Landlord for any out-of-pocket losses incurred, by reason of Tenant’s default under this Lease beyond applicable notice and cure periods set forth in this Lease. Notwithstanding anything in this Lease to the contrary, in the event Tenant does not timely pay (or obtain bonds reasonably acceptable to Landlord for) any amounts when due pursuant to Exhibit B attached hereto and a mechanic’s or materialmen’s lien is filed or threatened to be filed against the Premises, the Building or the Land, then Landlord shall have the right to immediately draw upon the Security Deposit after three (3) business days’ written notice to Tenant (it being understood that Landlord shall not be obligated to provide Tenant with any additional notice, and that no other notice nor cure or grace period shall be applicable with respect to Landlord’s right to immediately draw upon the Security Deposit as aforesaid) and, unless Tenant pays (or obtains bonds reasonably acceptable to Landlord for) such amounts, apply the proceeds to the payment of any amount Landlord may spend or become obligated to spend to timely discharge any mechanics’ or materialmen’s liens that might otherwise encumber the Building or the Land. If any portion of the Security Deposit is used or applied by Landlord in accordance with this Section, within four (4) business days after written notice to Tenant of such use or application, Tenant shall restore the Security Deposit by providing a replacement or additional Letter of Credit or additional cash such that Landlord is holding one or more Letters of Credit or cash in the aggregate amount of the Security Deposit required under this Lease. If Tenant shall fail to restore the Security Deposit as required herein within such four (4) business day period, and Landlord provides Tenant with a second written notice requesting such restoration of the Security Deposit, and thereafter Tenant fails restore the Security Deposit within three (3) business days after such second notice, such failure shall constitute an Event of Default (for which no additional notice and cure period shall apply). Tenant hereby authorizes Landlord to deposit the Security Deposit with the holder of any Mortgage if and to the extent required by said holder; provided, however, that such holder shall hold the Security Deposit subject to Tenant’s rights with respect to the Security Deposit set forth in this Lease and shall have executed and delivered an SNDA to Tenant, as required pursuant to Article XXI of this Lease.

          (b) If the Security Deposit shall be in the form of one or more letters of credit (each, a “ Letter of Credit ”), each Letter of Credit shall be an “evergreen” letter of credit and be unconditional and irrevocable, subject to the following terms and conditions. Such Letter

of Credit shall be (i) in form and substance satisfactory to Landlord in its sole discretion (with Landlord hereby approving the form Letter of Credit set forth on Exhibit H attached hereto), or in a form substantially similar to Exhibit H attached hereto; (ii) at all times in the amount of the Security Deposit, and shall permit multiple draws; (iii) issued by a commercial bank located in the Washington, D.C. metropolitan area or with a confirming bank reasonably acceptable to Landlord from which draws shall be permitted located in the Washington, D.C. metropolitan area pursuant to a written agreement attached to the Letter of Credit acceptable to Landlord (with Landlord hereby also accepting issuance of such Letter of Credit by the following banks (so long as such banks comply with the terms of this Article VI ): Silicon Valley Bank, UBS and Credit Suisse First Boston); (iv) made payable to, and expressly transferable and assignable at no charge by, the owner from time to time of the Building or, at Landlord’s option, the holder of any Mortgage (which transfer/assignment shall be conditioned only upon the execution of a written document in connection therewith; provided, however, that in the event the issuing bank of the Letter of Credit charges a fee for a transfer and/or assignment, any and all such fees shall be payable by Tenant); (v) payable at sight upon presentation of a simple sight draft at any Washington, D.C. metropolitan area branch office of the issuing bank of the Letter of Credit or a confirming bank from which draws shall be permitted acceptable to Landlord, and include the institution’s applicable form of presentation statement; (vi) of a term not less than one year; and (vii) at least thirty (30) days prior to the then-current expiration date of such Letter of Credit, renewed (or automatically and unconditionally extended) from time to time through the forty-fifth (45th) day after the expiration of the Lease Term. Notwithstanding anything in this Lease to the contrary, any cure or grace periods set forth in this Lease shall not apply if Tenant fails to timely comply with the requirements of subsection (vii) above, in which event Landlord shall have the right to immediately draw upon the Letter of Credit without notice to Tenant and hold the proceeds as the Security Deposit. Each Letter of Credit shall be issued by a commercial bank that has a credit rating with respect to certificates of deposit, short term deposits or commercial paper of at least P-2 (or equivalent) by Moody’s Investor Service, Inc., or at least A-2 (or equivalent) by Standard & Poor’s Corporation. If the issuer’s credit rating is reduced below P-2 (or equivalent) by Moody’s Investors Service, Inc. or below A-2 (or equivalent) by Standard & Poor’s Corporation, then Landlord shall have the right the require that Tenant obtain from a different issuer a substitute letter of credit that complies in all respects with the requirements of this Section, and Tenant’s failure to obtain such substitute letter of credit within fifteen (15) business days following Landlord’s written demand therefor (with no other notice or cure or grace period being applicable thereto, notwithstanding anything in this Lease to the contrary) shall entitle Landlord to immediately draw upon the then existing Letter of Credit in whole or in part, without notice to Tenant. In the event the issuer of any Letter of Credit held by Landlord is placed into receivership or conservatorship by the Federal Deposit Insurance Corporation or any successor or similar entity, then, effective as of the date such receivership or conservatorship occurs, said Letter of Credit shall be deemed to not meet the requirements of this Section, and, within fifteen (15) business days thereof, Tenant shall replace such Letter of Credit with other collateral acceptable to Landlord in its sole and absolute discretion, cash or a letter of credit that complies with the terms of this Article VI (and Tenant’s failure to do so within such fifteen (15) business days period shall, notwithstanding anything in this Lease to the contrary, constitute an Event of Default for which there shall be no notice or grace or cure periods being applicable thereto other than the aforesaid fifteen (15) business day period). Tenant shall be responsible for the payment of any and all third-party costs (not to exceed $2,500) incurred by Landlord or the holder of any Mortgage in connection with the review of any replacement Letter of Credit (including without limitation Landlord’s and such holder’s reasonable attorneys’ fees), which replacement is required pursuant to this Section or is otherwise requested by Tenant. Any failure or refusal of the issuer to honor the Letter of Credit shall be at Tenant’s sole risk and shall not relieve Tenant of its obligations hereunder with respect to the Security Deposit. Tenant shall have the right, at any time (except during the existence of an Event of Default or a monetary default that if not timely cured could result in an Event of Default), to replace a cash Security Deposit with a Letter of Credit meeting the requirements of this Lease, and to replace a Letter of Credit Security Deposit with cash. In the event a Letter of Credit is ever lost or destroyed while in Landlord’s possession, Tenant will cooperate, at no cost or charge to Landlord, with Landlord’s efforts to obtain a replacement Letter of Credit, and Landlord agrees to provide the issuer of such Letter of Credit with reasonable assurances and indemnities required by such issuer in order to cancel or replace such Letter of Credit.

          (c) Provided that on the first day of each Lease Year beginning on the first day of the second Lease Year no Event of Default (as defined in Section 19.1 ) or a monetary

default that if not cured within any applicable grace or notice and cure period could ripen to an Event of Default is then occurring, then Tenant shall have the right on each such date to reduce the Security Deposit by an amount equal to ten percent (10%) of the then total amount of the Security Deposit. If such Event of Default or monetary default is occurring, then upon the cure of such Event of Default or monetary default (Landlord being under no obligation to accept a cure of any such Event of Default), then Tenant will be deemed to have satisfied such condition for the applicable Lease Year. If all of the aforesaid conditions are met (or deemed to have been met after a cure of such an Event of Default or monetary default) and the Security Deposit is in the form of cash, upon Tenant’s request, Landlord shall within twenty (20) days of Tenant’s request of such amount release such portion of the Security Deposit to Tenant in the form of cash or other available funds. If all of the aforesaid conditions are met (or deemed to have been met after a cure of such an Event of Default or monetary default) and all or a portion of the Security Deposit is in the form of a Letter of Credit, upon Tenant’s request, Landlord shall within twenty (20) days notify the issuer of the Letter of Credit that the Letter of Credit may be reduced in the amount of the reduction so authorized, and the Security Deposit shall be so reduced in accordance with this Section 6.1(c) . Such reduction shall occur by means of delivery by Tenant to Landlord of an amendment to the Letter of Credit reducing the amount thereof as directed by Landlord, or a substitute Letter of Credit in such amount and in strict conformity with the terms of this Article VI , in which latter event, the original Letter of Credit will be promptly returned to Tenant. Notwithstanding anything contained in this Lease to the contrary, in no event shall the Letter of Credit be reduced unless the issuing bank receives prior written notice from Landlord, authorizing a reduction by a certain amount (it being understood that in no event shall the reduction exceed the amount so authorized by Landlord).

     6.2 In the event of the sale or transfer of Landlord’s interest in the Building, Landlord shall have the right to transfer the Security Deposit to the purchaser or assignee, and, in the event any portion of the Security Deposit is in the form of one or more Letters of Credit, Tenant shall, at Tenant’s sole expense, within ten (10) business days after Landlord’s request therefor, have such Letters of Credit amended or reissued by the issuing bank to indicate the new beneficiary. Tenant shall be responsible for paying and shall timely pay any fees charged by the issuing bank in such instance, but Tenant shall not be responsible for paying any fees charged by Landlord, its purchaser or assignee or their respective attorneys. If Landlord transfers the Security Deposit to a purchaser or assignee, Tenant shall look only to such purchaser or assignee for the return of the Security Deposit, and Landlord shall thereupon be released from all liability to Tenant for the return of the Security Deposit, provided such purchaser or assignee has expressly assumed the obligations of Landlord under this Lease and Tenant has received evidence of such assumption by such purchaser or assignee.

     6.3 Tenant hereby acknowledges that Tenant will not look to the holder of any Mortgage encumbering the Building for return of the Security Deposit if such holder, or its successors or assigns, shall succeed to the ownership of the Building, whether by foreclosure or deed in lieu thereof, except if and to the extent the Security Deposit is actually transferred to such holder.

ARTICLE VII
USE OF PREMISES

     7.1 Tenant shall use and occupy the Premises solely for general (non-medical) office purposes compatible with first-class office buildings in the jurisdiction in which the Building is located, and for no other use or purpose. Tenant shall not use or occupy the Premises for any unlawful purpose, or in any manner that will violate the certificate of occupancy for the Premises or the Building or that will constitute waste, nuisance or unreasonable annoyance to Landlord or any other tenant or user of the Building, or in any manner that will increase the number of parking spaces required for the Building or its full occupancy as required by law. Except to the extent of Landlord’s obligations to cause the base Building to comply with Laws, Tenant shall comply with all present and future laws (including, without limitation, the Americans with Disabilities Act (the “ ADA ”) and the regulations promulgated thereunder, as the same may be amended from time to time), ordinances (including without limitation, zoning ordinances and land use requirements), regulations, orders and recommendations (including, without limitation, those made by any public or private agency having authority over insurance rates) concerning the use, occupancy and condition of the Premises and all machinery, equipment, furnishings, fixtures and improvements therein (collectively, “ Laws ”), all of which shall be complied with in a timely manner at Tenant’s sole expense. If any such Law requires an occupancy or use permit or license for the Premises or the operation of the business

conducted therein, then Tenant shall obtain and keep current such permit or license at Tenant’s expense and shall promptly deliver a copy thereof to Landlord. Use of the Premises is subject to all easements, covenants, conditions and restrictions of record. Tenant shall not use any space in the Building for the sale of goods to the public at large or for the sale at auction of goods or property of any kind. Tenant shall not conduct any operations, sales, promotions, advertising or special events (but expressly excluding special events on the rooftop terrace (if constructed in accordance with the terms of this Lease)) in the Building outside of the Premises without Landlord’s prior written consent, not to be unreasonably withheld, conditioned, or delayed.

     7.2 Tenant shall pay before delinquency any business, rent or other taxes or fees that are now or hereafter levied, assessed or imposed upon Tenant’s use or occupancy of the Premises, the conduct of Tenant’s business at the Premises, or Tenant’s equipment, fixtures, furnishings, inventory or personal property. If any such tax or fee is enacted or altered so that such tax or fee is levied against Landlord or so that Landlord is responsible for collection or payment thereof, then Tenant shall pay as additional rent the amount of such tax or fee.

     7.3 (a) Tenant shall not cause or permit any Hazardous Materials (as defined below) to be generated, used, released, stored or disposed of in or about the Building (including the Premises), provided that Tenant may use and store reasonable quantities of standard cleaning materials as may be reasonably necessary for Tenant to conduct normal general office use operations in the Premises provided the same are handled, stored and disposed of in accordance with all Laws. At the expiration or earlier termination of this Lease, Tenant shall surrender the Premises to Landlord free of Hazardous Materials and in compliance with all Environmental Laws; provided that Tenant shall not be obligated to remove or remediate (i) any Hazardous Materials which have been generated, used, released, stored or disposed of in or about the Premises or the Building by any party other than Tenant or Tenant’s Invitees (hereinafter defined) prior to the Lease Commencement Date, or (ii) any Hazardous Materials which have been generated, used, released, stored or disposed of in or about the Building by any party other than Tenant or Tenant’s Invitees at any time during the Lease Term. For purposes of this Lease, “ Hazardous Materials ” means (a) asbestos and any asbestos containing material and any substance that is then defined or listed in, or otherwise classified pursuant to, any Environmental Law or any other applicable Law as a “hazardous substance,” “hazardous material,” “hazardous waste,” “infectious waste,” “toxic substance,” “toxic pollutant” or any other formulation intended to define, list, or classify substances by reason of deleterious properties such as ignitability, corrosivity, reactivity, carcinogenicity, toxicity, reproductive toxicity, or Toxicity Characteristic Leaching Procedure (TCLP) toxicity, (b) any petroleum and drilling fluids, produced waters, and other wastes associated with the exploration, development or production of crude oil, natural gas, or geothermal resources, and (c) any petroleum product, polychlorinated biphenyls, urea formaldehyde, radon gas, radioactive material (including any source, special nuclear, or by-product material), medical waste, chlorofluorocarbon, lead or lead-based product, and any other substance whose presence could be detrimental to the Building or hazardous to health or the environment. For purposes of this Lease, “ Environmental Law ” means any present and future Law and any amendments (whether common law, statute, rule, order, regulation or otherwise), permits and other requirements or guidelines of governmental authorities applicable to the Building and relating to the environment and environmental conditions or to any Hazardous Material (including, without limitation, CERCLA, 42 U.S.C. § 9601 et seq., the Resource Conservation and Recovery Act of 1976, 42 U.S.C. § 6901 et seq., the Hazardous Materials Transportation Act, 49 U.S.C. § 1801 et seq., the Federal Water Pollution Control Act, 33 U.S.C. § 1251 et seq., the Clean Air Act, 42 U.S.C. § 7401 et seq., the Toxic Substances Control Act, 15 U.S.C. § 2601 et seq., the Safe Drinking Water Act, 42 U.S.C. § 300f et seq., the Emergency Planning and Community Right-To-Know Act, 42 U.S.C. § 1101 et seq., the Occupational Safety and Health Act, 29 U.S.C. § 651 et seq., and any so-called “Super Fund” or “Super Lien” law, any Law requiring the filing of reports and notices relating to hazardous substances, environmental laws administered by the Environmental Protection Agency, and any similar state and local Laws, all amendments thereto and all regulations, orders, decisions, and decrees now or hereafter promulgated thereunder concerning the environment, industrial hygiene or public health or safety).

          (b) Notwithstanding any termination of this Lease, Tenant shall indemnify and hold Landlord, its employees and agents harmless from and against any damage, injury, loss, liability, charge, demand or claim based on or arising out of the presence or removal of, or failure to remove, Hazardous Materials generated, used, released, stored or disposed of by

Tenant or any Invitee (as defined in Article IX ) in or about the Building, whether before or after the Lease Commencement Date; provided, however, that Tenant’s obligation to indemnify Landlord pursuant to the terms of this Subsection shall be applicable and shall be enforceable only to the extent that Landlord has suffered an actual and demonstrable loss directly caused by the breach or default of Tenant, and provided further that in no event shall Tenant have any liability to Landlord for claims based on interruption of or loss to Landlord’s business or for claims for which Landlord is insured or required to be insured under the terms of this Lease. In addition, Tenant shall give Landlord immediate verbal and follow-up written notice of any actual or threatened Environmental Default (hereinafter defined), which Environmental Default Tenant shall cure in accordance with all Environmental Laws and to the satisfaction of Landlord and only after Tenant has obtained Landlord’s prior written consent, which shall not be unreasonably withheld. For purposes of this Lease, “ Environmental Default ” means any of the following by Tenant or any Invitee: a violation of an Environmental Law, subject to any right to contest the same available under applicable law provided there is no immediate threat of enforcement action by governmental authorities; a release, spill or discharge of a Hazardous Material on or from the Premises the Building which Tenant shall fail to commence remediation or removal within three (3) business days of such release and thereafter continuously and diligently pursue such remediation or removal to completion in accordance with all Laws and Environmental Laws; an environmental condition requiring responsive action for which Tenant shall fail to commence such action within three (3) business days of such condition and thereafter continuously and diligently pursue such action to completion in accordance with all Laws and Environmental Laws; or an emergency environmental condition for which Tenant shall fail to commence remediation within one (1) business day of the occurrence of such condition and thereafter continuously and diligently pursue such remediation to completion in accordance with all Laws and Environmental Laws. Upon any Environmental Default, in addition to all other rights available to Landlord under this Lease, at law or in equity, Landlord shall have the right but not the obligation to immediately enter the Premises, to supervise and approve any actions taken by Tenant to address the Environmental Default, and, if Tenant fails to immediately address same in accordance with the terms of this Lease, Landlord may perform, at Tenant’s sole cost and expense, any lawful action necessary to address same.

          (c) Landlord shall not cause or permit any Hazardous Materials to be generated, used, released, stored or disposed of in or about the Building, provided that Landlord may use and store reasonable quantities of construction materials and standard cleaning materials as may be reasonably necessary for Landlord or its property manager to conduct normal general office use operations in the Building, and to provide any cleaning services required under this Lease, provided the same are handled, stored and disposed of in accordance with all Laws.

          (d) Landlord represents that, except as identified in that certain Phase I Environmental Site Assessment prepared by EBI Consultants and dated July 3, 2003 (the “ Report ”), to Landlord’s actual knowledge as of the date of this Lease, based solely and exclusively on the Report and no further or additional inspection or inquiry made, the Building does not contain Hazardous Materials in violation of Environmental Laws. Landlord shall indemnify and hold Tenant harmless from and against any and all damages, claims, liabilities and expenses (including reasonable attorneys’ fees) suffered by or claimed against Tenant arising out of (i) Landlord’s failure to comply with the terms of Subsection 7.3(c) above, and (ii) Landlord’s breach of its representation set forth in the first sentence of this Section 7.3(d) ; except, to the extent such accident, injury, damage failure, breach or default is a result of or in any way caused by Tenant’s or any of its Invitees’ negligence, misconduct or wrongful act or omission and except, further, that Landlord’s obligation to indemnify Tenant pursuant to the terms of this Subsection shall be applicable and shall be enforceable only to the extent that Tenant has suffered an actual and demonstrable loss directly caused by the breach or default by Landlord; and provided, however, that in no event shall Landlord have any liability to Tenant for claims based on the interruption of or loss to Tenant’s business or for any indirect losses or consequential damages or for claims for which Tenant is insured or required to be insured under the terms of this Lease. Notwithstanding anything to the contrary in this Lease, (i) this Subsection 7.3(d) shall not apply to the holder of any Mortgage, and (ii) no holder of a Mortgage shall have any obligation under Subsection 7.3(c) above, but any person or entity claiming by, through or under any such Mortgage that obtains ownership of the Building shall be responsible to perform Landlord’s obligation under the terms of Subsection 7.3(c) during such period of time as it shall have ownership of the Building.

     7.4 Except as expressly set forth to the contrary in Exhibit B attached hereto with respect to improvements that Landlord expressly agrees to construct, Landlord at its sole expense and not subject to reimbursement pursuant to Article V shall take all steps necessary to cause the common areas of the Building as a whole including, but not limited to, all base Building restrooms, water fountains and elevator equipment located in the common areas of the Building and the Premises to comply with Title III of the ADA to the extent same does not comply with Title III of the ADA as of the date of this Lease. After Landlord complies with the preceding sentence of this Section, Landlord shall at its expense (subject to reimbursement pursuant to Article V to the extent permitted thereby) take all steps necessary to cause the common areas of the Building as a whole including, but not limited to, all base Building restrooms, water fountains and elevator equipment located in the common areas of the Building and the Premises to comply with Title III of the ADA. Notwithstanding the foregoing terms of this Section 7.4 , after Landlord initially delivers the Premises in the condition required by the terms of this Lease, to the extent any non-compliance is a result of the use or occupancy of the Premises, a change in Laws, or any action or inaction of Tenant or any Invitee, or if any improvements made by Landlord to comply with the ADA benefit solely the Premises, then such compliance shall be at Tenant’s cost. Except as expressly provided in the foregoing terms of this Section 7.4 , Tenant at its sole cost and expense shall be solely responsible for taking any and all measures which are required to cause the Premises to comply with the ADA. Any Alterations made or constructed by Tenant for the purpose of complying with the ADA or which otherwise require compliance with the ADA shall be done in accordance with this Lease; provided, that Landlord’s consent to such Alterations shall not constitute either Landlord’s assumption, in whole or in part, of Tenant’s responsibility for compliance with the ADA, or representation or confirmation by Landlord that such Alterations comply with the provisions of the ADA.

ARTICLE VIII
ASSIGNMENT AND SUBLETTING

     8.1 Except as provided in this Lease, Tenant shall not assign, transfer or otherwise encumber (collectively, “ assign ”) this Lease or all or any of Tenant’s rights under this Lease or interest in this Lease, or sublet or permit anyone to use or occupy (collectively, “ sublet ”) the Premises or any part of the Premises, without obtaining the prior written consent of Landlord, which consent may be withheld or granted in Landlord’s sole and absolute discretion. Notwithstanding the foregoing sentence, (a) provided that at the time request is made for approval of assignment or subletting pursuant to this Section no Event of Default shall exist, and subject to Landlord’s rights pursuant to Sections 8.3, 8.4 and 8.5 below, Landlord shall not unreasonably withhold, delay or condition its consent to any proposed assignment or subletting of the Premises, provided that (i) the use of the Premises pursuant to such assignment or sublease is in compliance with Article VII of this Lease; (ii) the proposed assignee or subtenant is of a type and quality consistent and compatible with a first-class office building and with the Building and its tenants, and is not an entity that enjoys sovereign immunity (other than an entity of the United States Federal government or the District of Columbia government) or an entity that intends to use the space as medical offices or as a drug clinic; (iii) Landlord is reasonably satisfied with the financial condition of the assignee under any such assignment or the sublessee under any such sublease to perform its general business obligations and its obligations under this Lease (taking into account that Tenant shall remain liable for the obligations of such assignee or sublessee under this Lease following any approved subletting or assignment); (iv) the initial Tenant remains fully liable as a primary obligor jointly and severally with any subtenant or assignee for the payment of all rent and other charges under this Lease and for the performance of all its other obligations under this Lease; and (v) any assignment is for all of Tenant’s rights and obligations under this Lease, and (b) so long as the proposed subtenant complies with the terms of subparts (i), (ii) and (iv) of subpart (a) of this sentence and Tenant has not subleased or assigned (including the proposed assignment of sublease) more than ten percent (10%) of the Premises, Landlord’s consent to a proposed sublease shall not be required. Except as otherwise expressly provided in Section 8.7 below, no assignment, sublet or right of occupancy under this Lease may be effectuated by operation of law or otherwise without the prior written consent of Landlord. Any attempted assignment, transfer or other encumbrance of this Lease or all or any of Tenant’s rights under this Lease or interest in this Lease, and any sublet or permission to use or occupy the Premises or any part of the Premises not in accordance with this Article VIII shall be void and of no force or effect. Any assignment or subletting, Landlord’s consent thereto, or Landlord’s collection or acceptance of rent from any assignee or subtenant shall not be construed either as waiving or

releasing Tenant from any of its liabilities or obligations under this Lease as a principal and not as a guarantor or surety, or as relieving Tenant or any assignee or subtenant from the obligation of obtaining Landlord’s prior written consent (if required) to any subsequent assignment or subletting. For any period during which an Event of Default exists under this Lease, Tenant hereby authorizes each such assignee or subtenant to pay said rent directly to Landlord upon receipt of notice from Landlord specifying same. Landlord’s collection of such rent shall not be construed as an acceptance of such assignee or subtenant as a tenant. Tenant shall not mortgage, pledge, hypothecate or encumber (collectively “ pledge ”) this Lease without Landlord’s prior written consent, which consent may be granted or withheld in Landlord’s sole and absolute discretion. Tenant shall pay to Landlord an administrative fee equal to one thousand five hundred dollars ($1,500) plus all third-party out-of-pocket expenses (including reasonable attorneys’ fees and accounting costs) incurred by Landlord in connection with Tenant’s request for Landlord to give its consent to any assignment, subletting, or pledge. The form of any sublease or assignment, which sublease or assignment is subject to Landlord’s approval hereunder, shall also be subject to Landlord’s approval, which will not be unreasonably withheld, conditioned or delayed. Tenant shall deliver to Landlord a fully-executed copy of each agreement evidencing a sublease, assignment or pledge within ten (10) days after Tenant’s execution thereof (regardless of whether Landlord’s consent was required or obtained).

     8.2 If Tenant is a partnership, then any event (whether voluntary, concurrent or related) resulting in a dissolution of Tenant, any withdrawal or change (whether voluntary, involuntary or by operation of law) of partners owning a controlling interest in Tenant (including each general partner), or any structural or other change having the effect of limiting the liability of the partners shall be deemed a voluntary assignment of this Lease subject to the provisions of this Article. If Tenant is a corporation (or a partnership with a corporate general partner), then any event (whether voluntary, concurrent or related) resulting in (i) a dissolution, merger, consolidation or other reorganization of Tenant (or such corporate general partner), or (ii) the sale or transfer or relinquishment of the interest of shareholders who, as of the date of this Lease, own a controlling interest of the capital stock of Tenant (or such corporate general partner), shall be deemed a voluntary assignment of this Lease subject to the provisions of this Article; provided, however, that the foregoing portion (ii) of this sentence shall not apply to corporations whose stock is traded through a national or regional exchange or over-the-counter market immediately prior to the transaction. If Tenant is a limited liability company, then any dissolution of Tenant or a withdrawal or change, whether voluntary, involuntary or by operation of law, of members owning a controlling interest in Tenant shall be deemed a voluntary assignment of this Lease. In addition, a transfer of all or substantially all of the assets of Tenant, either by merger, consolidation, or otherwise shall be deemed to be an assignment under this Article VIII .

     8.3 If at any time during the Lease Term Tenant desires to assign, sublet or pledge all or part of this Lease or the Premises, then in connection with Tenant’s request to Landlord for Landlord’s consent thereto, Tenant shall give notice to Landlord in writing (“ Tenant’s Request Notice ”) containing: the identity of the proposed assignee, subtenant or other party and a description of its business; the terms of the proposed assignment, subletting or other transaction; the commencement date of the proposed assignment, subletting or other transaction (the “ Proposed Sublease Commencement Date ”); the area proposed to be assigned, sublet or otherwise encumbered (the “ Proposed Sublet Space ”); the most recent financial statement or other evidence of financial responsibility of such proposed assignee, subtenant or other party; and a certification executed by Tenant and such party stating whether or not any premium or other consideration is being paid for the assignment, sublease or other transaction. Landlord shall, subject to the terms of Section 8.4 below, grant or withhold its consent to such proposed assignment, sublease or other transaction pursuant to the terms set forth in this Article VIII within fifteen (15) business days of its receipt of Tenant’s Request Notice provided such Tenant’s Request Notice contains all of the required information.

     8.4 If at any time during the Lease Term Tenant desires to assign or sublet twenty thousand (20,000) rentable square feet or more of the Premises or the term for the Proposed Sublet Space is for ninety-five percent (95%) or more of the remainder of the Lease Term then in effect (a “ Recapturable Sublease ”), when Tenant delivers Tenant’s Request Notice, such notice will specify that it is sent for the additional purpose of determining whether Landlord will exercise its recapture rights, and not have to contain the identity of the proposed assignee, subtenant or other party, the certification stating whether or not any premium or other

consideration is being paid, and a description of its business or the most recent financial statement or other evidence of financial responsibility of such proposed assignee, subtenant or other party notwithstanding the terms of Section 8.3 above. Landlord shall have the right in its sole and absolute discretion to terminate this Lease with respect to the Proposed Sublet Space that is a Recapturable Sublease by sending Tenant written notice of such termination within thirty (30) days after Landlord’s receipt of Tenant’s Request Notice. If Landlord does not terminate this Lease with respect to the Proposed Sublet Space that is a Recapturable Sublease (or if Landlord fails to send a notice to Tenant electing to terminate this Lease with respect to such space), then if at any time prior to the date that is one hundred eighty (180) days after the date Landlord receives Tenant’s Request Notice, Tenant identifies a specific subtenant or assignee or otherwise intends to enter into a sublease, assignment or similar transaction, Tenant shall (if not contained in the original notice) deliver a supplement to the Tenant’s Request Notice containing the identity of the proposed assignee, subtenant or other party and a description of its business and the most recent financial statement or other evidence of financial responsibility of such proposed assignee. Thereafter, Landlord shall approve or disapprove Tenant’s request in the specific Tenant’s Request Notice within fifteen (15) business days of its receipt of Tenant’s Request Notice provided such Tenant’s Request Notice contains all of the required information. If (i) Tenant fails to deliver the foregoing supplement to Tenant’s Request Notice specifying the applicable additional information prior to the expiration of the foregoing one hundred eighty (180) day period, or (ii) Landlord does not approve a Tenant’s Request Notice that is timely made prior to the expiration of the foregoing one hundred eighty (180) day period, then Tenant shall again, if Tenant at any time desires to enter into a Recapturable Sublease, provide another Tenant’s Request Notice and Landlord shall once again have the right to recapture such space in accordance with the terms of this Article VIII. If the Proposed Sublet Space does not constitute the entire Premises and Landlord exercises its option to terminate this Lease with respect to the Proposed Sublet Space, then (a) Tenant shall tender the Proposed Sublet Space to Landlord on the Proposed Sublease Commencement Date and such space shall thereafter be deleted from the Premises, and (b) as to that portion of the Premises which is not part of the Proposed Sublet Space, this Lease shall remain in full force and effect except that Base Rent and additional rent shall be reduced pro rata. The cost of any construction required to permit the operation of the Proposed Sublet Space separate from the balance of the Premises shall be paid by Tenant to Landlord as additional rent under this Lease. If the Proposed Sublet Space constitutes the entire Premises and Landlord elects to terminate this Lease, then Tenant shall tender the Proposed Sublet Space to Landlord, and this Lease shall terminate, on the Proposed Sublease Commencement Date.

     8.5 If any sublease or assignment (whether by operation of law or otherwise, including, without limitation, an assignment pursuant to the provisions of the Bankruptcy Code or any other Insolvency Law) provides that the subtenant or assignee thereunder is to pay any amount in excess of the rental and other charges due under this Lease, then whether such excess be in the form of an increased monthly or annual rental, a lump sum payment, payment for the sale, transfer or lease of Tenant’s fixtures, leasehold improvements, furniture and other personal property (not including bona fide sales on market terms of any movable furniture, furnishings, personal property and equipment), or any other form (and if the subleased or assigned space does not constitute the entire Premises, the existence of such excess shall be determined on a pro-rata basis), Tenant shall pay to Landlord fifty percent (50%) of any such excess or other premium applicable to the sublease or assignment (less Tenant’s reasonable out-of-pocket costs incurred in subleasing, for brokerage commissions, Tenant’s attorneys’ fees, marketing costs, rental abatements, improvement costs and improvement allowances, which cost shall be amortized over the term of the sublease for purposes of determining such excess amounts due to Landlord under this Lease on account of such sublease), which amount shall be paid by Tenant to Landlord (unless such payment is otherwise waived, in whole or in part, by Landlord in writing) as additional rent upon such terms as shall be specified by Landlord and in no event later than thirty (30) days after any receipt thereof by Tenant. Acceptance by Landlord of any payments due under this Section shall not be deemed to constitute approval by Landlord of any sublease or assignment, nor shall such acceptance waive any rights of Landlord under this Lease. Landlord shall have the right to inspect and audit Tenant’s books and records relating to any sublease or assignment.

     8.6 All restrictions and obligations imposed pursuant to this Lease on Tenant shall be deemed to extend to any subtenant, assignee, licensee, concessionaire or other occupant or transferee, and Tenant shall cause such person to comply with such restrictions and obligations.

Any assignee shall be deemed to have assumed obligations as if such assignee had originally executed this Lease and at Landlord’s request shall execute promptly a document confirming such assumption. Each sublease is subject to the condition that if the Lease Term is terminated or Landlord succeeds to Tenant’s interest in the Premises by voluntary surrender or otherwise, at Landlord’s option, the subtenant shall be bound to Landlord for the balance of the term of such sublease and shall attorn to and recognize Landlord as its landlord under the then executory terms of such sublease or, at Landlord’s sole option, the subtenant shall execute a direct lease with Landlord on Landlord’s then-current standard form.

     8.7 Notwithstanding anything contained in this Article VIII to the contrary, provided no Event of Default remains uncured under this Lease, Tenant may, without prior written notice to Landlord and without Landlord’s prior written consent and without being subject to Landlord’s rights and Tenant’s obligations set forth in Sections 8.4 and 8.5 , assign or transfer its entire interest in this Lease: (a) to a corporation or other business entity which is the successor corporation (herein sometimes referred to as a “ Successor Corporation ”) in a bona fide sale transaction of Tenant, whether by merger, consolidation or sale of all or substantially all of the assets or ownership interests of Tenant, provided that such successor corporation shall have a creditworthiness (e.g., assets and capitalization) and net worth (which shall be determined on a pro forma basis using generally accepted accounting principles consistently applied and using the most recent financial statements) immediately following such transaction at least equal to the creditworthiness and net worth of Tenant as of the date that is immediately prior to such merger, consolidation or sale, and provided that the Successor Corporation shall assume in writing to Landlord’s reasonable satisfaction all of the obligations and liabilities of Tenant under this Lease; or (b) to a corporation or other business entity (herein sometimes referred to as a “ Related Corporation ”) which shall control, be controlled by or be under common control with Tenant, provided that Tenant shall provide Landlord with written notice that such assignment or transfer has occurred within two (2) business days of such assignment or transfer. For the purpose of determining the creditworthiness and net worth of Tenant as set forth in the preceding sentence, the creditworthiness (e.g., assets and capitalization) and net worth (which shall be determined on a pro forma basis using generally acceptable accounting principles consistently applied and using the most recent financial statements) of a guarantor will be included in such determination provided that such guarantor has agreed in writing to guaranty the obligations of Tenant or Successor Corporation (as applicable) and the form of such guaranty is acceptable to Landlord in its reasonable discretion. In the event of any such assignment or subletting, Tenant shall remain fully liable as a primary obligor for the payment of all rent and other charges required under this Lease and for the performance of all obligations to be performed by Tenant under this Lease. For purposes of clause (b) above, “ control ” shall be deemed to be ownership of more than fifty percent (50%) of the stock or other voting interest of the controlled corporation or other business entity. Together with Tenant’s notice to Landlord pursuant to this Section, Tenant shall submit to Landlord sufficient information regarding the transaction as is reasonably necessary for Landlord to confirm that the transaction meets the qualifications set forth in this Section. Any Successor Corporation or Related Corporation as defined in this Section 8.7 above shall be referred to herein as “ Permitted Transferee ”. If the Security Deposit under the terms of this Lease is in the form of a Letter of Credit, then Tenant shall at Tenant’s sole cost, within five (5) business days (for which no notice and cure period will apply) of the date of such transfer, cause any such Letter of Credit to be amended or reissued to reflect a transaction contemplated by the terms of this Section 8.7 , and Tenant’s failure to promptly cause such amendment or reissuance will be an Event of Default hereunder.

ARTICLE IX
MAINTENANCE AND REPAIRS

     9.1 Tenant, at Tenant’s sole cost and expense, shall promptly make all repairs, perform all maintenance, and make all replacements in and to the Premises that are necessary to keep the Premises in first-class condition and repair, in a clean, safe and tenantable condition, and otherwise in accordance with all Laws and the requirements of this Lease, subject to Landlord’s obligations set forth in Section 9.2 below. Tenant shall maintain all fixtures, furnishings and equipment located in, or exclusively serving, the Premises in clean, safe and sanitary condition, shall take good care thereof and make all required repairs and replacements thereto. Tenant shall give Landlord prompt written notice of any defects or damage to the structure of, or equipment or fixtures in, the Building or any part of the Building. Tenant shall suffer no waste or injury to any part of the Premises, and shall, at the expiration or earlier termination of the

Lease Term, surrender the Premises in an order and condition comparable to their order and condition on the Lease Commencement Date, except for ordinary wear and tear and as otherwise provided in Article XVII . Except as otherwise provided in Article XVII , all injury, breakage and damage to the Premises and to any other part of the Building caused by any act or omission of any invitee, agent, employee, subtenant, assignee, contractor, client, family member, licensee, customer or guest of Tenant (collectively, “ Invitees ”) or Tenant, shall be repaired by and at Tenant’s expense, except that Landlord shall have the right at Landlord’s option, after twenty (20) days prior written notice to Tenant (except in the case of an emergency, in which event no prior notice shall be required) to make any such repair and to charge Tenant for all costs and expenses incurred in connection therewith if Tenant does not perform such required repairs within such twenty (20) day period, provided that if such required repairs cannot reasonably be effected within such twenty (20) day period and Tenant begins such required repairs promptly within such twenty (20) day period, then, except in the event of an emergency, Tenant shall have such additional time as is reasonably necessary to perform such repairs, provided that such additional period shall not exceed ninety (90) days from Landlord’s initial notice to Tenant. Landlord shall provide and install replacement tubes for building standard fluorescent light fixtures identified on Exhibit O (subject to reimbursement pursuant to Article V ); all other bulbs and tubes for the Premises shall be provided and installed by Tenant at Tenant’s expense.

     9.2 Except as otherwise provided in this Lease, Landlord shall (subject to reimbursement pursuant to Article V ) keep the exterior and demising walls, load bearing elements, foundations, roof and common areas that form a part of the Building, Garage, Fitness Center, exterior windows, base Building restrooms and the building standard mechanical, water, electrical, HVAC and plumbing systems, pipes and conduits, and life safety systems that are provided by Landlord in the operation of the Building (collectively, the “ Building Structure and Systems ”), clean and in good operating condition consistent with similar first-class buildings and, promptly after becoming aware of any item needing repair, will make repairs thereto. Notwithstanding any of the foregoing to the contrary, maintenance and repair of special tenant areas, facilities, finishes and equipment (including, but not limited to, any special fire protection equipment, telecommunications and computer equipment, kitchen/galley equipment, air-conditioning equipment serving the Premises only and all other furniture, furnishings and equipment of Tenant and all Alterations) shall be the sole responsibility of Tenant and shall be deemed not to be a part of the Building Structure and Systems.

     9.3 (a) In the event that Landlord fails to perform any maintenance or repair obligations of Landlord expressly set forth under this Lease with respect to the Premises (such failure, a “ Delayed Repair ”), and (a) such failure shall continue for a period of twenty (20) days after receipt of written notice from Tenant to Landlord and any lender of Landlord (the “ First Repair Self Help Notice ”) or, if such failure can not reasonably be cured within twenty (20) days, then such longer period as may be required for such cure provided that Landlord commences such cure within such twenty (20)-day period and diligently pursues such cure to completion (provided that such period shall not be extended beyond the date that is ninety (90) days after the First Repair Self Help Notice), and (b) such failure shall continue for ten (10) business days after receipt of an additional written notice from Tenant to Landlord and any lender of Landlord following the expiration of the period described in clause (a) above (the “ Second Repair Self Help Notice ”), then Landlord shall reimburse Tenant for either (x) a portion of the costs and expenses actually incurred by Tenant in curing such Delayed Repair, in an amount equal to the difference between such total costs and expenses actually incurred by Tenant less Tenant’s proportionate share of such costs and expenses, if and to the extent such expenses are includable as Operating Expenses pursuant to the terms of this Lease or (y) the costs and expenses actually incurred by Tenant in curing such Delayed Repair, if such expenses are not so includable as Operating Expenses (with Landlord hereby agreeing that such amounts shall not be included in the Operating Expenses for the Building) (as applicable, the “ Excess Repair Costs ”) within thirty (30) days after Landlord has received from Tenant an invoice therefor (and Tenant has provided a copy of same to any lender of Landlord). The First Repair Self Help Notice and the Second Repair Self Help Notice each shall include a statement in all capitals and bold face font that Tenant intends to exercise this right to self help, and shall identify in reasonable detail the basis for the self help and the actions Tenant intends to undertake to perform the Delayed Repair. Further notwithstanding anything to the contrary contained in this Lease, Tenant’s right to perform any such self help pursuant to this Section 9.3 is conditioned

upon strict compliance by Tenant with the following requirements: Tenant shall ensure that (i) all such work shall be performed solely by contractors, subcontractors and design consultants, as applicable, who are bonded (if bonds are reasonably available for the type and scope of work being performed), licensed in the District of Columbia, qualified and recognized as reputable within their field, (ii) each entity performing such work shall have obtained public liability and worker’s compensation insurance policies covering all persons who will perform such work in amounts customary for comparable work in buildings comparable to the Building, and (iii) all such work shall be performed in a good, workmanlike, first-class and prompt manner, and in accordance with all applicable laws and the requirements of any insurance company insuring the Building or any portion thereof. Further notwithstanding anything to the contrary contained in this Lease, the self help right provided to Tenant under this Section 9.3 shall not be applicable to any repair or maintenance obligations that affect the Building Structure and Systems or common areas. Further notwithstanding anything to the contrary contained in this Lease, Tenant shall not have the right to exercise any such self help rights against any landlord except for the landlord who failed to perform the Delayed Repair.

          (b) In the event that Landlord fails to perform any maintenance or repair obligations of Landlord expressly set forth under this Lease with respect to the Building Structure and Systems or common areas that renders any material portion of the Premises untenable or inaccessible (such failure, a “ Structural Delayed Repair ”), and (a) such failure shall continue for a period of ten (10) business days after receipt of written notice from Tenant to Landlord and any lender of Landlord (provided Tenant has been given the address to which such notices to Landlord&#821