PURCHASE AGREEMENT

Affiliate :  When used with reference to any Person, any Person that, directly or indirectly through one or more intermediaries controls, is controlled by, or is under common control with, the specified Person (the term "control" for this purpose, shall mean the ability, whether by the ownership of shares or other equity interests, by contract or otherwise, to elect a majority of the directors of a corporation, independently to select the managing partner of a partnership or the Managing Member of a limited liability company, or otherwise to have the power independently to remove and then select a

majority of those Persons exercising governing authority over an entity, and control shall be conclusively presumed in the case of the direct or indirect ownership of 50% or more of the equity interests).  In the case of Purchaser, Affiliate shall also mean any member of Purchaser and any entity, the accounts of which will be or are consolidated with those of Purchaser in its consolidated financial statements.

Ancillary Parcel :  The area of the Land identified as such on Exhibit A (Sheet 2 of 3 and Sheet 3 of 3).

Anticipated Outside Closing Date :  The four hundred fiftieth (450 ^th ) calendar day after the Due Diligence Termination Date (or, if the 450 ^th calendar day is not a Business Day, on the first Business Day thereafter), subject to extension on a day by day basis for any failure by Seller to provide the approvals contemplated by Section 8 within the time periods in which Seller is required to provide such approvals.

Approved Concept Development Plans :  As defined in Section 3A(e) .

Approved Concept Plan and Proffers :  The Concept Plan and those certain Proffers associated with ZMAP 1990-0014 approved by the Loudoun County Board of Supervisors on December 17, 1991.  Copies of the approved Concept Plan and approved Proffers are attached as Exhibit E and Exhibit F , respectively, to this Agreement.

Business Day :  Any day other than a Saturday, a Sunday or a day on which banking institutions in New York, New York, or Washington, D.C., are not open for the normal conduct of banking business.

Century Boulevard CPAP :  The construction plans and profiles for the Century Boulevard Extension.

Century Boulevard Easement Agreement :  As defined in Section 7B(b) .

Century Boulevard Extension :  As defined in Section 3A(c) .

Closing :  As defined in Section 11(a) .

Closing Statement :  As defined in Section 11(d) .

COE :  The United States Army Corps of Engineers.

Deed :  The Special Warranty Deed substantially in the form attached as Exhibit B to this Agreement.

Deposit :  As defined in Section 2(b) .

Due Diligence Period :  The period of time beginning on the Effective Date and ending at midnight on the Due Diligence Termination Date.

Due Diligence Termination Date :  As defined in Section 2(b) .

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Escrow Agent :  Loudoun Commercial Title, LLC,  108 South Street SE, Suite G, Leesburg, VA 20175-3732.

Future Building :  The building on the Option 1 Parcel or the Option 2 Parcel that is identified as “Future Building” on Exhibit A to this Agreement and the Approved Concept Development Plans, including the Pre-Emptive Option Parcel.

Governmental Authority :  The United States of America, the Commonwealth of Virginia, Loudoun County, and any agency, department, commission, board, bureau, instrumentality or political subdivision of any of the foregoing, now existing or hereafter created, having jurisdiction over the use, development or improvement of the Land or any part thereof.

Headquarters Building Parcel :  The area of the Land identified as such on Exhibit A (Sheet 1 of 3).

Land :  The Option 1 Parcel or the Option 2 Parcel, as applicable, to be included as a part of the Property.

Legal Requirements :  All laws, statutes, ordinances, orders, rules, regulations, codes, executive orders and requirements, of all Governmental Authorities, whether now or hereafter in force, ordinary and extraordinary, foreseen as well as unforeseen, to the extent they are applicable to the Land, the use thereof or the improvements constructed, or to be constructed, thereon, [and all other covenants, conditions and restrictions of record affecting the use and occupancy of the Land or any improvements thereon.]

Non-Pond Concept Development Plans :  As defined in Section 3A(e) .

Option 1 Parcel :  The parcel of unimproved real property containing 41.97 acres, more or less, that is a part of the Overall Property and is described on Sheet 2 of 3 of Exhibit A to this Agreement.

Option 2 Parcel :  The parcel of unimproved real property containing 42.06 acres, more or less, which is a part of the Overall Property and is described on Sheet 3 of 3 of Exhibit A to this Agreement.

Pending Rezoning :  As defined in Section 3A(b) , including any Seller-initiated change that does not impose any additional proffer obligations or other conditions or development restrictions on the Land, other than those limiting the Land to development of PD-OP uses under the 1993 Zoning Ordinance of Loudoun County, Virginia, that include buildings and other improvements with a maximum gross floor area of 450,000 square feet.

Person :  An individual, corporation, trust, association, unincorporated association, estate, partnership, joint venture, limited liability company or other legal entity, including a governmental entity.

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Phase 1 Building :  The building identified as the "Phase 1 Building" on Sheet 1 of 3 of Exhibit A .

Pond Concept Development Plans :  As defined in Section 3A(e) .

Pond Easement Agreement :  As defined in Section 9(i) .

Pre-Emptive Option Agreement :  The Pre-Emptive Option Agreement substantially in the form attached as Exhibit H to this Agreement.

Pre-Emptive Option Parcel .  The area of the Land identified as such on Exhibit A (Sheet 2 of 3 as to the Option 1 Parcel and Sheet 3 of 3 as to the Option 2 Parcel).

Proffer Allocation and Infrastructure Agreement :  An agreement to be signed by Seller and Purchaser at the Closing, in recordable form, containing the provisions contemplated by Section 9(j) and any other provision of this Agreement that, by its terms, is to be included in the Proffer Allocation and Infrastructure Agreement.  The Proffer Allocation and Infrastructure Agreement shall be recorded among the applicable Land Records as a part of the Closing and shall be a covenant running with the Property and the Overall Property.

Property :  As defined in Recital B .

Property Owners Association Covenants :  The Property Owner Association Covenants in the form attached as Exhibit C to this Agreement, in their present form or as modified or amended by an agreement between Seller and Purchaser signed and delivered before the Due Diligence Termination Date.

Purchaser’s Intended Use :  The development and construction on the Land of office buildings and related improvements containing 450,000 square feet of gross floor area as generally set forth on the Approved Concept Development Plans.

Purchaser’s Surviving Obligations :  As defined in Section 3(c) .

Repurchase Option Agreement :  The Repurchase Option Agreement in the form attached as Exhibit D to this Agreement.

Seller’s Closing Certificate :  As defined in Section 11(b)(2) .

Seller’s Retained Property :  The Overall Property less and except the Property to be sold to Purchaser pursuant to this Agreement.

SWM/BMP Facility :  As defined in Section 3A(f) .

Wetlands Disturbance Request :  As defined in Section 8(a) .

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(a)            Payment of Purchase Price .  The purchase price of the Property (the “ Purchase Price ”) shall be (i) FOURTEEN MILLION FOUR HUNDRED THOUSAND AND NO/100 DOLLARS ($14,400,000.00), if the Closing occurs on or before the Anticipated Outside Closing Date, or (ii) FIFTEEN MILLION ONE HUNDRED TWENTY THOUSAND AND NO/100 DOLLARS ($15,120,000.00), if the Closing occurs after the Anticipated Outside Closing Date.  On the Closing Date, and subject to the terms and conditions of this Agreement, Purchaser shall pay the Purchase Price, less the Deposit and subject to the adjustments and prorations pursuant to Section 11(d) , in the manner provided in Section 11(a) .

(b)            Deposit .  Within two (2) Business Days (hereafter defined) after the Effective Date, Purchaser shall pay the sum of One Thousand Dollars ($1,000) (the “ Initial Deposit ” ) by wire transfer of immediately available funds to the Escrow Agent.  Unless this Agreement has previously been terminated pursuant to Section 3(d) , on or before the sixtieth (60 ^th ) day after the Effective Date (or, if the sixtieth (60 ^th ) day after the Effective Date is not a Business Day, on or before the first Business Day thereafter) (the “ Due Diligence Termination Date ”), the Purchaser shall pay to the Escrow Agent, by wire transfer of immediately available funds, an additional deposit in the amount of Nine Hundred Thousand Nine Hundred and Ninety-nine Dollars ($999,000) to be held by the Escrow Agent as an additional good faith deposit under this Agreement (the “ Additional Deposit ”).  If Purchaser does not pay the Additional Deposit to the Escrow Agent on or before the Due Diligence Termination Date, with time being of the essence, this Agreement shall automatically terminate on the Due Diligence Termination Date, the Escrow Agent shall promptly pay the Initial Deposit to Purchaser and neither party shall have any further liability or obligation to the other party under this Agreement, except for the Purchaser’s Surviving Obligations.  As used in this Agreement, the term “ Deposit ” means the Initial Deposit and the Additional Deposit.  The Escrow Agent shall invest the Deposit in one or more federally-insured interest-bearing accounts as Purchaser may direct and all interest earned thereon shall be deemed to be part of the Deposit, except as otherwise expressly provided in this Agreement.  The Escrow Agent shall pay the Deposit to Seller on the Closing Date in accordance with Section 11(a) or shall pay the Deposit to Seller or Purchaser in accordance with the other provisions of this Agreement.  After the Due Diligence Termination Date, the entire Deposit shall be non-refundable to Purchaser except as otherwise expressly provided in this Agreement.

(c)            Holding of Deposit .  The Escrow Agent shall hold the Deposit, in trust, and shall disburse the Deposit in accordance with the provisions of this Agreement and the following additional provisions:

(1)           If this Agreement is terminated pursuant to Section 2(b) because the Purchaser does not pay the Additional Deposit to the Escrow Agent on or before the Due Diligence Termination Date, or if this Agreement is terminated by the Seller or the Purchaser pursuant to Section 3(d) , Section 3(k) , Section 4(b) or Section 4(c) , the Escrow Agent shall return the Deposit to Purchaser promptly after receipt of a written demand from Purchaser.  For this purposes, the Escrow Agent shall be fully protected in relying on a written demand from Purchaser stating that it is entitled to the return of the Deposit pursuant to Section 2(b) ,

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Section 3(d) , Section 3(k) , Section 4(b) or   Section 4(c) , and the Escrow Agent shall disregard any contrary instructions or demands received by it from Seller.

(2)           Except as otherwise provided in Section 2(c)(1) , if this Agreement is terminated in accordance with its terms after the Due Diligence Termination Date and thereafter either Seller or Purchaser makes a written demand on the Escrow Agent for payment of the Deposit, the Escrow Agent shall give written notice of such demand to the other party.  If the Escrow Agent does not receive a written objection from the other party to the proposed payment of the Deposit within 10 days after the giving of such notice, the Escrow Agent shall pay the Deposit to the party making the demand.  If the Escrow Agent receives a written objection from the other party within the 10-day period, the Escrow Agent shall continue to hold the Deposit until otherwise directed by written instructions from Seller and Purchaser or until otherwise directed by a court of competent jurisdiction.

(3)           In the event of a dispute concerning the disposition of the Deposit, the Escrow Agent shall have the right at any time to deposit any cash funds held by it under this Agreement with the clerk of the court of general jurisdiction of the city or county in which the Property is located.  The Escrow Agent shall give written notice of such deposit to Seller and Purchaser.  Upon such deposit the Escrow Agent shall be relieved and discharged of all further obligations and responsibilities hereunder.

(4)           The duties of the Escrow Agent are only as herein specifically provided and are purely ministerial in nature.  The Escrow Agent shall incur no liability whatsoever except for willful misconduct or gross negligence, as long as the Escrow Agent has acted in good faith.  Seller and Purchaser each releases the Escrow Agent from any act done or omitted to be done by the Escrow Agent in good faith in the performance of its duties hereunder.

(5)           Seller and Purchaser shall jointly and severally indemnify and hold harmless the Escrow Agent from and against any loss, damage, liability or expense incurred by the Escrow Agent not caused by its willful misconduct or gross negligence, arising out of or in connection with its entering into this Agreement and the carrying out of its duties hereunder, including the reasonable costs and expenses of defending itself against any claim of liability or participating in any legal proceeding.  The Escrow Agent may consult with counsel of its choice, and shall have full and complete authorization and protection for any action taken or suffered by it hereunder in good faith and in accordance with the opinion of such counsel.

(6)           The Escrow Agent is acting as a stakeholder only with respect to the monies to be deposited in the escrow.  Upon making delivery of such monies in the manner herein provided, the Escrow Agent shall have no further liability hereunder.

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(7)           The Escrow Agent may resign at will and be discharged from its duties or obligations hereunder by giving notice in writing of such resignation specifying a date when such resignation shall take effect; provided , however , that (i) prior to such resignation a substitute escrow agent is approved in writing by Seller and Purchaser, which approval shall not be unreasonably withheld or delayed, or (ii) the Escrow Agent shall deposit the Deposit with a court of competent jurisdiction in the city or county in which the Property is located.  After such resignation, the Escrow Agent shall have no further duties or liability hereunder.

(8)           The Escrow Agent shall sign a counterpart of this Agreement solely for the purpose of confirming that the Escrow Agent is holding and will hold the Deposit in escrow and will disburse the Deposit pursuant to the provisions of this Agreement.

(d)            Failure to Pay Initial Deposit .  If Purchaser fails to pay the Initial Deposit to the Escrow Agent within the time required by Section 2(b) , this Agreement shall automatically terminate and neither party shall have any further liability or obligation to the other party under this Agreement.

(a)            Purchaser’s Right to Inspect .  Purchaser and its authorized agents shall have the right, at Purchaser’s risk, cost and expense, to enter the Land at any time or times before the Closing Date, during normal business hours and after reasonable advance notice, for purposes of making such investigations and studies, including appraisals, architectural and engineering studies, surveys, soil tests, environmental studies, financial, market analysis, development and economic feasibility studies, as Purchaser deems necessary or desirable to evaluate the Property.  Purchaser shall provide Seller at least one Business Day’s notice in writing or by telephone in advance of its entry upon the Property for purposes other than visual inspections.  No advance notice shall be required for visual inspections of the Property.  Purchaser shall not make or perform any borings or other physically invasive or destructive tests without Seller’s prior written consent, which shall not be unreasonably withheld, delayed or conditioned.  Telephone notices, when permitted, shall be given to Seller’s representative, Arthur N. Fuccillo, at (301) 692-2222.

(b)            Purchaser’s Insurance .  Purchaser shall not enter the Land for any purpose other than visual inspections until Purchaser has delivered to Seller a certificate of insurance evidencing that Purchaser has obtained a policy of Commercial General Liability Insurance protecting Purchaser, as named insured, and Seller, as an additional insured, against liability for bodily injury, death and property damage occurring in or about the Land, with such policy to afford protection to the limit of not less than $3,000,000 combined single limit annual aggregate for bodily injury, death and property damage.  Such certificate shall also provide that the policy will not be canceled or terminated, or the limits of liability thereunder reduced, unless Seller receives at least 20 days advance notice thereof.

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(c)            Purchaser’s Indemnity .  Purchaser shall not make any physical changes to the Property (other than soil borings and associated tree clearing as reasonably approved by Seller) and shall indemnify and hold harmless Seller from and against (i) all physical damage to the Property caused by Purchaser’s tests and investigations, (ii) all loss, liability or damage suffered or incurred by Seller arising out of or resulting from injury or death to individuals or damage to personal property caused by the tests and investigations conducted by, or at the direction of, Purchaser, and (iii) all reasonable costs and expenses (including reasonable attorneys’ fees and disbursements) incurred by Seller in connection with any action, suit, proceeding, demand, assessment or judgment incident to the foregoing, unless (in each case) such loss, liability or damage arises out of Seller’s negligence or willful misconduct.  Purchaser’s obligations to indemnify Seller pursuant to this Section 3(c) and Purchaser’s obligations to return the Information to Seller pursuant to Section 3(d) shall survive the termination of this Agreement and are referred to in this Agreement as “ Purchaser’s Surviving Obligations . ”

(d)            Termination by Purchaser .  Purchaser may terminate this Agreement at any time on or before the Due Diligence Termination Date by giving Seller and the Escrow Agent written notification (the “ Termination Notice ” ) that Purchaser elects not to consummate the purchase of the Property in accordance with the terms of this Agreement.  Purchaser shall have the absolute right, in its sole and absolute discretion, to determine whether to give the Termination Notice.  If the Termination Notice is timely given on or before the last day of the Due Diligence Period, the Escrow Agent shall promptly return the Initial Deposit to Purchaser pursuant to Section 2(c)(1) , and, except for Purchaser’s Surviving Obligations, no party shall have any further liability to any other party under this Agreement.  If this Agreement is terminated pursuant to Section 2(b) , this Section 3(d) , Section 3(k) , Section 4(b) or Section 4(c) , Purchaser agrees, within 15 days after the date of termination, to deliver to Seller copies of all title reports, title commitments, surveys, written engineering reports and written environmental reports prepared by third parties for Purchaser during the period of time in which this Agreement is in effect, and to return to the Seller all written Information (defined in Section 3(f) ) previously delivered by Seller to Purchaser pursuant to this Agreement.  All third party reports and studies shall be delivered to Seller for information only without any right to rely thereon.

(e)            Additional Information .  Within three (3) Business Days after the Effective Date, Purchaser shall deliver to Seller a written notice identifying all information Purchaser desires to receive with respect to the Property, including the physical, regulatory and title characteristics of the Property.  Within five (5) Business Days after receipt of Purchaser’s notice, Seller shall either deliver copies of the information requested by Purchaser, if such information is within Seller’s possession or control, without representation or warranty as to the accuracy or completeness of such information, or if Seller does not have possession or control of some or all of the information requested by Purchaser, Seller shall inform Purchaser in writing of that fact within the period of five (5) Business Days.

(f)            Confidentiality .  Prior to the Closing, Purchaser shall hold all information concerning the Property obtained by Purchaser from Seller (the “ Information ” ) in

confidence and shall not at any time disclose or permit the disclosure of the Information to any Person without Seller’s prior written consent.  Purchaser further agrees to use the Information only for purposes of evaluating the Property in connection with its purchase of the Property in accordance with the terms of this Agreement.  Notwithstanding the foregoing, (i) Purchaser may disclose the Information to its legal counsel, accountants, lenders, existing and prospective investors and other Persons who need to review the Information in connection with Purchaser’s purchase of the Property in accordance with the terms of this Agreement, (ii) the provisions of this Section 3(e)   shall not apply to any portions of the Information that are available from public sources other than through the actions of Purchaser or its agents, and (iii) Purchaser may disclose the Information to the extent that such disclosure is required by law, regulation or court order, but Purchaser first shall provide written notice thereof to Seller.  Before the Closing Date, neither Seller nor Purchaser shall make any public announcements concerning the sale of the Property pursuant to this Agreement without first obtaining the prior written consent of the other except Purchaser may make general announcements to its employees and Purchaser may make any disclosures required by applicable law, court order or Governmental Authority, including, but not limited to any disclosures required to be made by the Securities and Exchange Commission as part of any required periodic filing.

(g)            Purchaser’s Covenant Not to Sue .  Except for claims arising out of Seller’s actual fraud or a breach of any of the Seller’s covenants, representations or warranties expressly set forth in this Agreement or any document executed by or on behalf of Seller at the Closing,  Purchaser, for itself and its agents, affiliates, successors and assigns, hereby agrees not to assert against Seller, its agents, affiliates, successors and assigns, any rights, claims or demands at law or in equity, arising out of the physical, environmental, economic or legal condition of the Property, including any claim for indemnification or contribution arising under (i) any Environmental Law (defined in Section 5(f) ), (ii) any similar federal, state or local statute, rule or ordinance relating to the liability of property owners for environmental matters, or (iii) the common law.

(a)             Existing Zoning .  On the Effective Date, the Property is zoned PD-OP under the 1972 zoning ordinance Loudoun County, Virginia.  A copy of the approved Concept Plan and a copy of the approved Proffers are attached Exhibit E and Exhibit F , respectively, to this Agreement.  Pursuant to the approved Concept Plan the Property may be developed up to a FAR of 0.4.  Seller and Purchaser agree that the amount of gross floor area to be allocated to the Property shall consist of 450,000 square feet.

(b)            Purchaser acknowledges that, as of the Effective Date, Seller is pursuing a rezoning of the Overall Property, as well as other portions of the property owned by Seller which is known as “Dulles Town Center,” and that Seller’s pending rezoning application includes the Land (the " Pending Rezoning ").  Purchaser agrees to cooperate with Seller in obtaining the Board of Supervisor’s approval of the Pending Rezoning, provided the Pending Rezoning does not impose any additional proffer obligations or other conditions or development restrictions on the Land, other than those limiting the Land to development of PD-OP uses under the 1993 Zoning Ordinance of Loudoun

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County, Virginia, that include buildings and other improvements with a maximum gross floor area of 450,000 square feet.  Seller agrees that the Pending Rezoning shall not restrict the ability of Purchaser to develop the Property for Purchaser's Intended Use.   Subject to the restriction contained in Section 7A(c) , this Agreement shall not preclude Purchaser from pursuing a subsequent amendment to the rezoning applicable to the Property, including, but not limited to increasing the gross floor area or FAR applicable to such Property, provided such subsequent rezoning does not decrease the density of development otherwise permitted on the Overall Property (exclusive of the Property).

(c)             Century Boulevard .  Purchaser acknowledges that, as of the Effective Date, Seller has constructed a portion of a road known as Century Boulevard, as required by the Approved Concept Plan and Proffers, that terminates at the location shown on Exhibit A .   Exhibit A also shows the proposed extension of Century Boulevard across a portion of the Overall Property and the Land (the “ Century Boulevard Extension ”).  Purchaser agrees, after the Closing Date, to construct, at its expense, the Century Boulevard Extension as shown on Sheet 3 of 3 of Exhibit A as the "Century Boulevard Extension", as provided in Section 7A(b) .  Additionally, if, on the Closing Date, Purchaser purchases the Option 2 Parcel, Purchaser shall thereafter diligently and continuously pursue, at its sole cost and expense, the construction of that portion of the private access road within the area depicted as Private Road Joint Maintenance Area on Sheet 3 of 3 of Exhibit A   that is   necessary to permit the access to Seller’s Retained Property as shown on Sheet 3 of 3 of Exhibit A .  Furthermore, at any time after the Closing Date, Purchaser shall, upon receipt of a written request from Seller, without consideration, dedicate to public use the portion of the Option 2 Parcel that is necessary to construct Future Century Boulevard as shown on Sheet 3 of 3 of Exhibit A ,   provided Seller has bonded the construction of Future Century Boulevard with Loudoun County and has agreed to construct Future Century Boulevard within twelve (12) months after the land dedication is completed.  Seller agrees that, at all times during the construction of Future Century Boulevard, Purchaser shall have reasonable access to the Land and Seller shall use commercially reasonable efforts to minimize any disruption to Purchaser, and its operations on its property, during any such construction.  The provisions of this Section 3A(c) shall be set forth in the Proffer Allocation and Infrastructure Agreement.

(d)             Elimination of Part of Century Boulevard .  Purchaser also agrees that, as part of the Pending Rezoning, Seller shall have the right to seek and shall seek, to eliminate the requirement of the Approved Concept Plan and Proffers that Century Boulevard be extended by the construction of an additional road from the terminus of the Century Boulevard Extension across the Overall Property and Option 1 Parcel and extending to a bridge over Atlantic Boulevard.  The portion of the Century Boulevard Extension that Seller has the right to and shall seek to eliminate is described on Sheet 1 of 3 of Exhibit A as "Century Boulevard To Be Eliminated."

(e)            Concept Development Plan .  Before the Effective Date, Purchaser prepared and submitted to Seller, for its approval, two (2) concept development plans showing its general concept for the development of improvements on the Option 1 Parcel (if the Option 1 Parcel is purchased) and two (2) concept development plans showing its general concept for the development of improvements on the Option 2 Parcel (if the

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Option 2 Parcel is purchased), including, in each case, the approximate location and height of the buildings to be constructed on the Land, the general type of materials (including color) to be used for the exterior façade of the first building to be constructed and the approximate location of entrances to and exits from the Land in relation to the existing dedicated streets that abut or are adjacent to the Land (the “ Concept Development Plans ”).  Seller has approved such Concept Development Plans.  The Concept Development Plans prepared by Purchaser and approved by Seller are referred to in this Agreement as the “ Approved Concept Development Plans .”  The Approved Concept Development Plans are attached as Exhibit G   to this Agreement and consist of four (4) different site layouts, two (2) covering the Option 1 Parcel and two (2) covering the Option 2 Parcel.  Two (2) of the Approved Concept Development Plans, provide for a SWM/BMP Facility (the " Pond Concept Development Plans " ) and the other two (2) concept development plans do not provide for a SWM/BMP Facility (the " Non-Pond Concept Development Plans " ). [ Note:   The term SWM/BMP Facility is defined in Section 1A.]

(f)            SWM/BMP Facility .  Purchaser shall have the right, in its sole discretion, to elect to develop and construct improvements on the Land utilizing either the Pond Concept Development Plans or the Non-Pond Concept Development Plans.  Purchaser shall deliver notice of its election to Seller on or before the Due Diligence Termination Date.  If Purchaser fails to deliver notice of its election to Seller on or before the Due Diligence Termination Date, Purchaser shall be conclusively deemed to have elected to develop and construct improvements on the Land utilizing the Non-Pond Concept Development Plans as part of its initial construction of the Phase 1 Building.  If Purchaser elects (or is deemed to elect) to develop and construct improvements on the Land utilizing the Non-Pond Concept Development Plans, then Seller shall have the right, at Closing, to reserve, for a period of fifty (50) years from the Closing Date (the “ Pond Construction Option Period ”), an easement over and across the Land (either the Option 1 Parcel or the Option 2 Parcel, as the case may be), in the location generally as shown on Exhibit G for the purposes of Seller’s future construction of a storm water management/BMP facility (" SWM/BMP Facility ") within such easement area, together with the right to receive reimbursement of a part of its design and construction costs pursuant to Section 9(j) during the first fifteen (15) years of the Pond Construction Option Period (the “Pond Construction Reimbursement Period”).  Purchaser shall also have the right, within the Pond Construction Option Period, to construct the SWM/BMP Facility, together with the right to receive reimbursement for a part of its design and construction costs pursuant to Section 9(j) during the Pond Construction Reimbursement Period.  The party, i.e., Seller or Purchaser, who desires to construct the SWM/BMP Facility shall notify the other party of its intention to do so at least ninety (90) days before it commences such construction.  Seller’s right to reserve the easement referred to in this subsection and the parties reimbursement obligations shall be included in the Proffer Allocation and Infrastructure Agreement.

(g)            Option 1 Parcel Tree Preservation Area .  The Approved Concept Development Plans for the Option 1 Parcel depict a “Potential Tree Preservation Area” on the Option 1 Parcel and Seller’s Retained Property.  Seller agrees that, if Purchaser acquires the Option 1 Parcel, Seller will not remove the mature stand of trees within the

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“Potential Tree Preservation Area” shown on Sheet 1 of 3 of Exhibit A and such area shall be preserved to protect the view shed from the Property.  The terms of this agreement shall be included in the Proffer Allocation and Infrastructure Agreement.

(h)            Architectural Review Board Approvals .  Seller and Purchaser acknowledge that the Approved Concept Development Plans do not include any elevations or materials for the building designated on Exhibit A and on the Approved Concept Development Plans as "Future Buildings".

(a)            Title Commitment and Survey .  Promptly after the Effective Date, Purchaser, at its expense, shall cause to be prepared a current, effective commitment for an ALTA policy of owner’s title insurance (1992 form or equivalent) for the Property (the “ Title Commitment ”) to be issued by Commonwealth Land Title Insurance Company, Lawyers Title Insurance Company, First American Title Insurance Company Chicago Title Insurance Company or another nationally recognized title insurance company (the “ Title Company ” ), which names Purchaser as the proposed insured.  Purchaser shall have the option to cause to be prepared, at its expense, a current ALTA/ACSM

 survey of the Property (the “ Survey ”).  Not later than 10 days before the Due Diligence Termination Date (the “ Title Delivery Date ”), Purchaser shall deliver to Seller a copy of the Title Commitment, accompanied by true, complete, and legible copies of all documents referred to in Schedule B to the Title Commitment.  Not later than 10 days before the Due Diligence Termination Date (the “ Survey Delivery Date ”), Purchaser shall deliver to Seller a copy of the Survey, if obtained.

(b)            Purchaser’s Title Objections .  If Purchaser, for any reason whatsoever, objects to the condition of Seller’s title to the Property, it shall do so by notifying Seller in writing on or before the Title Delivery Date concurrently with its delivery to Seller of a copy of the Title Commitment.  If Purchaser does not object to the condition of Seller’s title to the Property on or before the Title Delivery Date, Purchaser shall be conclusively deemed to have accepted the condition of title as set forth in the Title Commitment and to have approved all exceptions to title described in Schedule B to the Title Commitment other than the exceptions for unfiled mechanics’ liens, mortgages and other liens which may be removed by the payment of money.  Within five Business Days after receipt of Purchaser’s notice of title objections and a copy of the Title Commitment, Seller shall either agree in writing to cure such objections or shall notify Purchaser in writing that Seller is unable or unwilling to do so.  In the event Seller fails to give either notice required by the preceding sentence, Seller shall be deemed to have agreed to cure such objections.  If Seller timely notifies Purchaser that it is unable or unwilling to cure the title objections, Purchaser may terminate this Agreement within five Business Days thereafter by giving notice of termination to Seller, in which case this Agreement shall terminate on the date of Purchaser’s notice, the Escrow Agent shall return the Deposit to Purchaser pursuant to Section 2(c)(1) and neither party shall have any further liability or obligation to the other party under this Agreement except for the Purchaser’s Surviving

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Obligations.  If Purchaser does not terminate this Agreement pursuant to the preceding sentence, Purchaser shall be conclusively deemed to have waived the title objections, the title objections shall be deemed to be Permitted Exceptions (defined in Section 4(e) ) and Purchaser shall be obligated to purchase the Property in accordance with the terms of this Agreement without a reduction in the Purchase Price.  If Seller timely notifies Purchaser that it will cure the title objections or Seller is deemed to have agreed to cure such title objections, such title objections shall not be Permitted Exceptions and Seller shall be obligated to cure such objections on or before the Closing Date.  Any new exceptions to title contained in any update of the Title Commitment shall not be Permitted Exceptions unless approved in writing by Purchaser.

(c)            Purchaser’s Survey Objections .  If Purchaser, for any reason whatsoever, objects to any matter disclosed by the Survey, it shall do so by notifying Seller in writing on or before the Survey Delivery Date concurrently with its delivery to Seller of a copy of the Survey.  If Purchaser does not object to a matter disclosed by the Survey on or before the Survey Delivery Date, Purchaser shall be conclusively deemed to have accepted the Survey and to have approved all matters disclosed by the Survey.  Within five Business Days after receipt of Purchaser’s notice of survey objections and a copy of the Survey, Seller shall either agree in writing to cure such objections or shall notify Purchaser in writing that Seller is unable or unwilling to do so.  In the event Seller fails to give either notice required by the preceding sentence, Seller shall be deemed to have agreed to cure such objections.  If Seller timely notifies Purchaser that it is unable or unwilling to cure the survey objections, Purchaser may terminate this Agreement within five Business Days thereafter by giving notice of termination to Seller, in which case this Agreement shall terminate on the date of Purchaser’s notice, the Escrow Agent shall return the Deposit to Purchaser pursuant to Section 2(c)(1) and neither party shall have any further liability or obligation to the other party under this Agreement except for the Purchaser’s Surviving Obligations.  If Purchaser does not terminate this Agreement pursuant to the preceding sentence, Purchaser shall be conclusively deemed to have waived the survey objections, such survey objections shall be deemed to be Permitted Exceptions and Purchaser shall be obligated to purchase the Property in accordance with the terms of this Agreement without a reduction in the Purchase Price.  If Seller timely notifies Purchaser that it will cure the survey objections or Seller is deemed to have agreed to cure such survey objections, such survey objections shall not be Permitted Exceptions and Seller shall be obligated to cure such survey objections on or before the Closing Date.

(d)            Purchaser’s Failure to Obtain Title Commitment or Survey .  If Purchaser fails to deliver a copy of the Title Commitment to Seller on or before the Title Delivery Date, Purchaser shall be conclusively deemed to have approved all exceptions to title to the Property (other than exceptions for mortgages, mechanics’ liens and other liens which may be removed by the payment of money) which would have been disclosed by a title examination of the Property.  If Purchaser elects not to prepare the Survey or  fails to deliver a copy of the Survey to Seller on or before the Survey Delivery Date, Purchaser shall be conclusively deemed to have approved all matters that would be disclosed by a survey of the Property prepared in accordance with the “Minimum Standard Detail Requirements for ALTA/ACSM Land Title Surveys,” jointly adopted by ALTA, ACSM

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  and the National Society of Professional Engineers in 2005 with the accuracy of an Urban Survey.

(e)            Permitted Exceptions .  For purposes of this Agreement, the term “ Permitted Exceptions ” shall mean (i) the lien of current real estate taxes not yet due and payable, (ii) all other exceptions to title that are approved, or deemed approved, by Purchaser pursuant to Section 4(b) , (iii) all matters disclosed by a survey of the Property which are approved, or deemed approved, by Purchaser pursuant to Section 4(c) , (iv) if Purchaser does not deliver the Title Commitment to Seller on or before the Title Delivery Date, all exceptions to title to the Property (other than exceptions for mortgages, mechanics’ liens and other liens which may be removed by the payment of money) that would have been disclosed by a title examination of the Property if the Title Commitment had been obtained, (v) if Purchaser elects not to prepare the Survey or does not deliver the Survey to Seller on or before the Survey Delivery Date, all matters that would have been disclosed by the Survey if it had been obtained, (vi) all matters, whether or not of record, that arise out of the actions of Purchaser or its agents, employees or contractors, and (vii) the Property Owners Association Covenants.

(f)            Release of Liens .  On the Closing Date, Seller shall release all mortgages, deeds of trust and other liens securing obligations for the payment of fixed and determinable amounts of money that encumber the Property (it being agreed that the Purchase Price shall be applied at settlement for such purpose).  Purchaser acknowledges that the Overall Property is subject to the lien of the assessment associated with the Dulles Town Center Community Development Authority (" CDA ").  Within thirty (30) days after the Effective Date, Seller shall deliver to Purchaser a written statement from the administrator for the CDA setting forth the portion of the lien applicable to the Overall Property that would be allocable to each of the Option 1 Parcel and the Option 2 Parcel, together with the annual installment payable with respect to such liens and the amount required to prepay and obtain a release of the assessment lien applicable to each of the Option 1 Parcel and the Option 2 Parcel.  Seller and Purchaser acknowledge that the assessment lien applicable to the Overall Property is based on the potential for the CDA to issue bonds up to the aggregate principal amount of FIFTY MILLION AND NO/100 DOLLARS ($50,000,000.00), while the annual installment is based on the aggregate principal amount of bonds issued and outstanding on the Effective Date, which is THIRTY-SIX MILLION FIVE HUNDRED SIXTY THOUSAND AND NO/100 DOLLARS ($36,560,000.00) (the “ Existing Bonds ”).  It is anticipated that during the Due Diligence Period, the Seller and Purchaser will agree on how the assessment lien will be applied to the Option 1 Parcel and the Option 2 Parcel.  However, to the extent the assessment lien is not prepaid by Purchaser at the Closing, Seller agrees that Purchaser's maximum liability for the assessment lien and/or annual installments shall always be based on aggregate principal amount of the Existing Bonds and the payment schedule associated with the Existing Bonds.  If there is an increase in the principal amount of or a refinancing or refunding of the Existing Bonds, Purchaser’s obligations shall be based on the aggregate principal amount of the Existing Bonds and Seller shall be responsible for any increase in either the assessment lien and/or the annual installment associated with any increase in the aggregate principal amount of, or any refunding or/refinancing of, the Existing Bonds.  If there is a refunding or refinance of the Existing Bonds (without any

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increase in the term of the Existing Bonds) that reduces the annual installment, Purchaser shall be entitled to the benefit of such lesser annual installment unless Purchaser has previously prepaid the assessment lien applicable to the Land included in the Property.  The foregoing provisions shall be included in the Proffer Allocation and Infrastructure Agreement.

(a)            Organization and Authorization .  Seller is a limited liability company duly formed and validly existing under the laws of the Commonwealth of Virginia.  Seller has the legal power and authority to own, sell, convey and transfer the Property.  The individual who signs this Agreement on behalf of Seller has been duly authorized to do so by Seller.

(b)            No Conflicting Agreements .  The execution and delivery by Seller of, and the performance of and compliance by Seller with, the terms and provisions of this Agreement, do not (i) conflict with, or result in a breach of, the terms, conditions or provisions of, or constitute a default under, Seller’s Organizational Documents (defined below), or any other agreement or instrument to which Seller is a party or by which all or any part of the Property is bound, (ii) violate any restriction, requirement, covenant or condition to which all or any part of the Property is bound, (iii) to the knowledge of Seller, constitute a violation of any applicable code, resolution, law, statute, regulation, ordinance or rule applicable to Seller or the Property, (iv) constitute a violation of any judgment, decree or order applicable to Seller or specifically applicable to the Property, or (v) require the consent, waiver or approval of any third party.  As used in this Agreement, the term “ Seller’s Organizational Documents ” means the Articles of Organization and Operating Agreement pursuant to which Seller is organized.

(c)            Litigation .  There are no investigations, proceedings, actions, suits or claims pending against or, to Seller’s actual knowledge, threatened, against Seller or the Property or any part thereof.  Seller is not operating under or subject to, and Seller is not in default with respect to, any order, writ, injunction or decree that relates to the Property or any part thereof.

(d)            Condemnation Proceedings .  No condemnation or eminent domain proceedings affecting the Property, or any part thereof, are pending or, to Seller’s actual knowledge, threatened.

(e)            Compliance with Laws .  Seller has not received any written notice of any violations of law, statutes, rules, governmental ordinances, orders or requirements noted or issued by any governmental authority having jurisdiction over or affecting the Property which have not been resolved to the satisfaction of the issuer of the notice, nor does Seller have actual knowledge of any such violations, other than an unresolved issue involving the location of a park and ride facility that has been appealed by Seller to the Loudoun County Board of Supervisors.

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(f)            Environmental Conditions .  To Seller’s actual knowledge the Property does not contain, and there is not located on, in or under any part of the Property, any of the following: “toxic substances,” “toxic materials,” “hazardous waste,” “hazardous substances,” “pollutants,” or “contaminants” (as those terms are defined in the Resource, Conservation and Recovery Act of 1976, as amended (42 U.S.C. §6901 et . seq .), the Comprehensive Environmental Response Compensation and Liability Act of 1980, as amended (42 U.S.C. §9601 et . seq .), the Hazardous Materials Transportation Act, as amended (49 U.S.C. §5101 et . seq .), the Toxic Substances Control Act of 1976, as amended (15 U.S.C. §2601 et . seq .), the Clean Air Act, as amended (42 U.S.C. §1251 et . seq .) and any other federal, state or local law, statute, ordinance, rule, regulation, code, order, approval, policy and authorization relating to health, safety or the environment (said laws being hereafter referred to collectively as “ Environmental Laws ” ); asbestos or asbestos-containing materials; lead or lead-containing materials; oils; petroleum-derived compounds; pesticides; or polychlorinated biphenyls (all of which are hereafter collectively referred to as “ Hazardous Materials ”).  No part of the Property has been previously used by Seller, or to Seller’s actual knowledge, by any other Person, for the storage, manufacture or disposal of Hazardous Materials.  Seller has not received from any governmental body having authority any written complaint, order, citation or notice with regard to air emissions, water discharges, noise emissions and Hazardous Materials, if any, or any other environmental, health or safety matters affecting the Property or any part thereof.  To Seller’s actual knowledge, there are no underground storage tanks of any nature located on any of the Property.

(g)            Bankruptcy .  There is no bankruptcy, insolvency, rearrangement or similar action or proceeding, whether voluntary or involuntary, pending or, to Seller’s actual knowledge, threatened against Seller.

(h)            FIRPTA .  Seller is a “United States person” within the meaning of Sections 1445(f)(3) and 7701(a)(30) of the Internal Revenue Code of 1986, as amended.

(i)            No Binding Agreements .  Except for the Permitted Exceptions, Seller is not a party to, and the Property is not subject to, any agreements that will be binding on the Property or Purchaser on or after the Closing Date.

(j)            Zoning .  The Property is zoned PD-OP under the 1972 Loudoun County Zoning Ordinance, subject to the Approved Concept Plan and Proffers (including the existing Special Exceptions (if any) approved concurrently with such Approved Concept Plan and Proffers).  To the best of Seller’s actual knowledge, the Property is not subject to any other development conditions, proffers or restrictions except for those contained in the Property Owners Association Covenants.

(k)            Limitations on Seller’s Liability for Representations and Warranties .  Seller’s liability for a misrepresentation or breach of warranty under this Agreement shall be subject to the following limitations:

(1)            Seller’s representations and warranties are for the personal benefit of the Purchaser and no such representation or warranty may be assigned to or

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enforced by any other Person, except any permitted assignee or any assignee consented to by Seller.

(2)            Whenever a representation or warranty is made in this Agreement on the basis of the best knowledge or the actual knowledge of Seller or words of similar import, or whether Seller has received written notice, such representation or warranty is made with the exclusion of any facts disclosed to or otherwise actually known by Purchaser before the Due Diligence Termination Date, and is made solely on the basis of the actual, as distinguished from implied, imputed or constructive, knowledge on the date that such representation or warranty is made of Arthur N. Fuccillo, whom Seller represents to be the representative of Seller having responsibility for the management and sale of the Property and accordingly the individual responsible for being informed of matters relevant to this Agreement, without independent investigation or inquiry, and without attribution to Arthur N. Fuccillo of facts and matters otherwise within the personal knowledge of any other agent or employees of Seller or any other Person, and excluding, whether or not actually known by Arthur N. Fuccillo, any matter actually known to Purchaser or its agents or employees on the Due Diligence Termination Date.  For purposes of this Section 5(k)(2 ) , “actually known by Purchaser” shall mean any matter (i) disclosed by any written document delivered to or made available to Purchaser for its review, (ii) disclosed by any written report prepared for Purchaser by any employee, agent or independent contractor of Purchaser in connection with Purchaser’s due diligence or otherwise with respect to its acquisition of the Property, or (iii) disclosed to any employee, agent or independent contractor of Purchaser in connection with Purchaser’s due diligence or otherwise with respect to its acquisition of the Property, provided that such matter is within the scope of the duties or responsibilities of such employee, agent or independent contractor.

(3)           If, before the Closing Date, Purchaser obtains actual knowledge that any of the Seller’s representations or warranties is inaccurate and Purchaser nonetheless proceeds with the Closing, Seller shall not have any liability for any such matter regarding which Purchaser had actual knowledge before the expiration of the Closing Date.

(4)           The aggregate liability of Seller for all misrepresentations and breaches of warranties discovered prior to Closing shall not exceed $250,000, and shall be further limited to the direct, but not consequential or punitive, damages resulting from any such misrepresentations or breaches.  The preceding sentence shall not apply to actual fraud or intentional misrepresentation.

(5)           All representations and warranties contained in this Agreement shall survive the Closing, except that each of the representations and warranties in this Section 5 shall terminate nine (9) months after the Closing Date unless, within the nine-month period, Seller receives notice of a breach of such representation or warranty.

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(a)            Purchaser’s purchase of the Property is for the development and construction by Purchaser of certain improvements on the Property for its own use and use by its Affiliates and not for speculation in landholding or for resale (except for sales to Affiliates who will purchase for their own use and not for speculation in landholding or for resale), except for the Future Building.

(b)           Purchaser is a sophisticated investor with substantial experience in purchasing unimproved real property similar to the Property.  Purchaser will have the right to examine and inspect the physical nature and condition of the Property, including environmental conditions, and agrees to purchase the Property in its “as is” condition on the Effective Date, solely in reliance on its own tests, investigations and studies and not in reliance on any representations or warranties made by Seller with regard to those matters except as expressly set forth in this Agreement, the Deed, and the Seller’s Closing Certificate.  Neither Seller nor any other agent, partner, employee, or representative of Seller has made any representation or warranty regarding the physical condition of the Property, or any part thereof, or anything relating to the subject matter of this Agreement, except as expressly set forth in this Agreement, the Deed and the Seller’s Closing Certificate, and Purchaser, in signing and delivering this Agreement, has not and will not rely upon any statement, information, or representation to whomsoever made or given, whether to Purchaser or others, and whether directly or indirectly, verbally or in writing, made by any Person, except as expressly set forth in this Agreement, the Deed and Seller’s Closing Certificate.

(a)            Possession .  On the Closing Date, Seller agrees to give full, complete and actual possession of the Property to Purchaser, free and clear of all tenancies and other rights of occupancy in favor of third parties.

(b)            Affirmative Covenants .  Between the Effective Date and the Closing Date, Seller agrees to:

(1)           maintain the Property in its present order and condition and deliver the Property on the Closing Date in substantially the condition it is in on the Effective Date;

(2)           deliver to Purchaser, promptly after receipt by Seller, copies of all notices of violation issued by any board, bureau, commission, department or body of any municipal, county, state or federal government unit, or any subdivision thereof, with respect to the Property received by Seller after the Effective Date; and

(3)           in the event Seller becomes aware that any representation or warranty of Seller set forth in Section 5 will not be true and correct in all material

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respects on the Closing Date as if made at and as of the Closing Date, give prompt written notice thereof to Purchaser, which notice shall include all appropriate information related thereto that is in Seller’s possession or control.

(c)            Negative Covenants .  Between the Effective Date and the Closing Date, Seller agrees that, without Purchaser’s written consent in each case, it will not do any of the following:

(1)           voluntarily grant, create, assume or permit to be created any mortgage, lien, lease, encumbrance, easement, covenant, condition, right-of-way or restriction upon the Property or voluntarily take or permit any action adversely affecting the title to the Property as it exists on the date of this Agreement; or

(2)           permit occupancy of, or enter into any lease for all or any part of the Land.

(d)             Zoning/Proffers .  Seller agrees that Seller shall be responsible, at its sole cost and expense, for the performance of any and all of the Proffers included in the Approved Concept Plan and Proffers, including, but not limited to, any Proffers that would impact the Purchaser's ability to develop the Property or to obtain permits for Purchaser’s Intended Use.  Additionally, if the Pending Zoning is approved by the Board of Supervisors of Loudoun County before the Closing Date, Seller shall, at its sole cost and expense, be responsible for any proffers, development conditions or similar requirements associated with the Pending Rezoning unless otherwise agreed to in writing by Purchaser and set forth in the Proffer Allocation and Infrastructure Agreement.  Seller and Purchaser acknowledge that the Pending Rezoning may require the construction of the SWM/BMP Facility and that the Pending Rezoning and the COE, as part of its approval of Purchaser’s Wetlands Disturbance Request, may require the preservation of the mature stand of quality trees generally in the area depicted on Exhibit A   as "Potential Tree Preservation Area".  Seller shall not be obligated, and shall not agree, to the designation of the “Potential Tree Preservation Area” as a tree preservation area unless the Pending Rezoning, as finally approved by the Board of Supervisors, permits the portion of Century Boulevard that Seller has the right to and shall seek to eliminate (as described on Sheet 1 of 3 of Exhibit A as "Century Boulevard To Be Eliminated.") is eliminated from the Century Boulevard Extension.  If the Pending Rezoning, as finally approved by the Board of Supervisors, does not permit such portion of Century Boulevard to be eliminated, and the Option 2 Parcel is conveyed, Seller acknowledges that the Future Building may be located in the area designated as “Potential Tree Preservation Area.”  Seller's agreement with respect to the performance of the Proffers and/or any proffers, development conditions or similar requirements associated with the Pending Rezoning shall be set forth in the Proffer Allocation and Infrastructure Agreement, which shall be a covenant running with the land.  As part of such Pending Zoning, Purchaser agrees to commit that its first building will achieve a LEED certification of silver or better.

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(a)            Restriction on Resale of Land .

(1)           Except as otherwise provided in the next sentence, Purchaser agrees that, during the period beginning on the Closing Date and ending on the tenth (10 ^th ) anniversary of the Closing Date, it shall not sell to any Person (other than an Affiliate or Seller) any part of the Land.  This restriction shall not apply to (i) the sale of the Headquarters Building Parcel after the construction of the Phase 1 Building has been completed (as evidenced by the issuance by the applicable Governmental Authority of a certificate of occupancy), (ii) the sale of the Ancillary Parcel in conjunction with the sale of the Headquarters Building Parcel after the completion of construction of the Phase I Building, or (iii) the sale of the Ancillary Parcel after the completion of construction of a building thereon (as evidenced by the issuance by the applicable Governmental Authority of a certificate of occupancy).  Any Affiliate of the Purchaser who purchases all or any part of the Land from the Purchaser shall be subject to the same restrictions on sale as the Purchaser.

(2)           After the tenth (10 ^th ) anniversary of the Closing Date, Purchaser’s or an Affiliate’s right to sell any part of the Land upon which a building has not been constructed shall be subject to Seller’s rights under the Pre-Emptive Option Agreement.

(3)           The restrictions described in this Section 7A(a) shall be included in the Pre-Emptive Option Agreement.

(1)           Promptly after the Closing Date, Purchaser shall commence construction of the Century Boulevard Extension.  Purchaser may elect to construct the Century Boulevard Extension as a public road or a private road, but in either event the Century Boulevard Extension shall be constructed in accordance with the Approved Century Boulevard CPAP as a four lane median divided roadway to public road standards and in accordance with the same standards of construction used by Seller in constructing the portion of Century Boulevard completed before the Effective Date.  Purchaser shall thereafter prosecute the construction of the Century Boulevard Extension in good faith and with diligence and continuity.

(2)           If the Century Boulevard Extension is constructed as a private road, at the Closing Seller and Purchaser shall enter into a reciprocal easement agreement (the “ Century Boulevard Easement Agreement ”), in a form to be agreed upon by Seller and Purchaser, prior to the Due Diligence Termination Date, granting easements for the use of the Century Boulevard Extension, establishing maintenance standards, providing for sharing of the costs of maintaining the Century Boulevard Extension and containing such other provisions as may be mutually agreed upon.  The formula for sharing maintenance costs shall be based on the square footage of improvements utilizing

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the Century Boulevard Extension.  Additionally, if Purchaser acquires the Option 2 Parcel, the Century Boulevard Easement Agreement shall cover (i) that portion of the private road that extends from the Century Boulevard Extension and provides access to both the Option 2 Parcel and Seller’s Retained Property ( the “Private Road Joint Maintenance Area,” as shown of Sheet 3 of Exhibit A ), and shall include provisions establishing maintenance standards and the sharing of maintenance costs, and (ii) that portion of the private road that extends from the Private Road Joint Maintenance Area to Seller’s Retained Property (the “Seller’s Private Road” as shown on Sheet 3 of Exhibit A ) , which Seller’s Private Road shall be constructed and maintained by Seller at its expense.

(c)             Restrictions on Rezoning of Property .  Purchaser agrees that, during the period beginning on the Closing Date and ending on the twentieth (20 ^th ) anniversary of the Closing Date, it will not cause or permit the Land to be rezoned to permit a density of development greater than 450,000 square feet of office space, unless the increased density of development is for the purpose of constructing one or more additional office buildings on the Land that will be occupied solely by Purchaser or one or more of its Affiliates.  The foregoing restriction shall be included in the Proffer Allocation and Infrastructure Agreement.

(d)            Survival .  Purchaser’s obligations under this Section 7A shall survive the Closing.

(a)           If (i) the Board of Supervisors does not approve the Pending Rezoning before the Closing Date, and (ii) within five (5) years after the Closing Date, the applicable Governmental Authority approves the Pending Zoning, or another rezoning of the Overall Property, that permits the elimination of the extension of Century Boulevard described in Section 3A(d) , Purchaser shall have the right, by delivering notice to Seller within sixty (60) days after such approval becomes final (with time being of the essence), to require Seller to join with Purchaser in effecting the boundary line adjustment and the exchange transactions described in Section 7B(b) .  Seller agrees to give Purchaser written notice of the approval of such a rezoning and the commencement of such sixty (60) day period.  Purchaser’s right to deliver the notice referred to in this subsection is personal to Purchaser and may not be transferred or assigned to any other Person.

(b)           If Purchaser timely delivers to Seller the notice referred to in Section 7B(a) , Purchaser, at its sole cost and expense, shall promptly cause its civil engineers to prepare a boundary line adjustment plat that, when approved by the applicable Governmental Authority, will permit Seller to convey the part of the Option 1 Parcel not included in the Option 2 Parcel to Purchaser and will permit Purchaser to convey a part of the Option 2 Parcel to Seller so that, immediately after the exchange, Purchaser will be the sole owner of the Option 1 Parcel and Seller will be the Seller owner of the Option 2 Parcel.  Seller shall have the right to approve the boundary line adjustment plat, but agrees that its approval will not be unreasonably withheld, delayed or conditioned.  Promptly after the boundary line adjustment plat (in the form approved by Seller) is

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approved by the applicable Governmental Authority, Seller and Purchaser shall complete the exchange by the delivery of special warranty deeds. Each party shall transfer and convey to the other party good and marketable title to the land to be conveyed by it, free and clear of all liens, encumbrances, easements, rights-of-way, conditions and other matters affecting title other than those existing on the Closing Date or created on or after the Closing Date pursuant to this Agreement.  Each party shall pay the Virginia grantor’s tax with respect to the deed in which it is the grantor and all other transfer taxes and recording expenses with respect to the deed in which it is the grantee.  The parties shall not prorate or adjust current real estate taxes with respect to the land being exchanged.

(c)           This Section 7B shall not apply unless, at the time Purchaser delivers the notice referred to in Section 7B(a), the Option 2 Parcel is owned by Purchaser, by an Affiliate of Purchaser or by Purchaser and one or more of its Affiliates.

(a)            Loudoun County and COE Approval of SWM/BMP Facility .  If Purchaser elects to pursue one of the Pond Concept Development Plans pursuant to Section 3A(f) , Purchaser shall promptly prepare a written requested to be submitted to the Department of Environmental Quality (“ DEQ ”) or the COE, or both, as appropriate, to permit Purchaser to disturb wetlands to the extent necessary to permit the construction of the SWM/BMP Facility (the “ Wetlands Disturbance Request ”).  The Wetlands Disturbance Request and the accompanying documentation shall be prepared by Wetlands Studies and Solutions, Inc. and/or Dewberry and Davis, LLC, or another firm of wetland consultants and/or civil engineers selected by Purchaser and approved by Seller, such approval not to be unreasonably withheld, delayed or conditioned.  The design and location of the SWM/BMP Facility shall be in substantial conformity with the Approved Concept Development Plan showing such Facility and shall comply with all applicable Legal Requirements.  Purchaser shall deliver a copy of its proposed Wetlands Disturbance Request and accompanying documentation to Seller within ninety (90) days after the end of the Due Diligence Period so that Seller may determine whether the design and location of the proposed SWM/BMP Facility conforms to the Approved Concept Development Plans.  The provisions of Section 8(b)(1) relating to the review, revision and approval of Purchaser's proposed Site Plan shall apply to the review, revision and approval of Purchaser’s proposed Wetlands Disturbance Request.  Within 10 Business Days after approval (or deemed approval) by Seller, Purchaser shall submit the Wetlands Disturbance Request in the form approved (or deemed approved) to DEQ or COE, or both, as applicable.  If Purchaser constructs the SWM/BMP Facility, the cost of designing the SWM/BMP Facility and obtaining the necessary DEQ/COE and Loudoun County approvals for such Facility shall be paid 50% by Seller and 50% by Purchaser, including the costs associated with any required wetlands mitigation (including purchase of off-site mitigation credits).  The cost of construction of such SWM/BMP Facility shall be paid as

provided in the Proffer Allocation and Infrastructure Agreement.  This Section 8(a) shall not apply if Purchaser elects to pursue one of the Non-Pond Concept Plans.

(b)             Preparation and Approval of Site Plan and Century Boulevard CPAP .

(1)           Purchaser agrees, promptly after the end of the Due Diligence Period, (or promptly after the approval by DEQ or COE, or both if required, of Purchaser’s Wetlands Disturbance Request, if later) to prepare (1) a site plan for the Option 2 Parcel (the “ Site Plan ”), and (ii) the Century Boulevard CPAP.  The Site Plan and Century Boulevard CPAP shall be prepared by Dewberry & Davis, LLC, or another firm of civil engineers selected by Purchaser and approved by Seller, such approval not to be unreasonably withheld, delayed or conditioned.  The Site Plan and Century Boulevard CPAP shall be prepared in substantial conformity with the Approved Concept Development Plans that Purchaser elects to pursue, provided such Site Plan may be limited to the Phase 1 Building and shall comply with all applicable Legal Requirements.  Purchaser shall deliver a copy of its proposed Site Plan and Century Boulevard CPAP to Seller on or before the later to occur of (i) 30 Business Days after the end of the Due Diligence Period, or (ii) 60 Business Days after the approval by DEQ or COE, or both, as applicable, of Purchaser’s Wetlands Disturbance Request), so that Seller may determine whether the Site Plan and Century Boulevard CPAP conform to the Approved Concept Development Plan.  If Seller determines that the proposed Site Plan and Century Boulevard CPAP do not conform to the applicable Approved Concept Development Plan, Seller shall so notify Purchaser, specifying in what respects the proposed Site Plan and Century Boulevard CPAP do not so conform, and Purchaser shall revise the Site Plan and Century Boulevard CPAP to so conform it and shall resubmit the revised Site Plan and Century Boulevard CPAP to Seller for review for that purpose.  Purchaser and Seller shall act in good faith with diligence and continuity in preparing, reviewing and, if necessary, revising the Site Plan and Century Boulevard CPAP.  The initial review by Seller of the proposed Site Plan and Century Boulevard CPAP shall be completed within 10 Business Days after it is submitted by Purchaser and any subsequent review by Seller of any revisions thereto shall be completed within 10 Business Days after Purchaser’s submission of such revision.  In case of resubmissions or revisions, Seller may not disapprove any matter previously submitted and approved by Seller, except to the extent that such resubmission or revision affects any matter previously approved or deemed approved.  If Seller does not notify Purchaser of its determination with the 10-Business Day period, Seller shall be deemed to have determined that the proposed Site Plan and Century Boulevard CPAP or any revision thereof conforms to the Approved Concept Development Plan.

(2)            If Purchaser elects to pursue an Approved Concept Development Plan that includes the SWM/BMP Facility simultaneously with the construction of the Phase 1 Building and the DEQ/COE and Loudoun County have agreed that the SWM/BMP Facility can be installed in the area generally depicted on the applicable Approved Concept Development Plan, then the construction of such Facility shall be pursued simultaneously with the Site Plan either as a part of the

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Site Plan or as a separate construction plan and profile (the " SWM/BMP CPAP Facility "), and the review, revision and approval process for the Site Plan set forth in Section 8(b)(1) above shall apply equally to the SWM/BMP CPAP Facility if it is pursued as a separate plan.  Regardless of whether the SWM/BMP CPAP Facility is pursued as a part of the Site Plan or as a separate CPAP, or if later pursued by Purchaser within the Pond Construction Option Period, the engineering and design costs of such plan and any wetlands mitigation costs shall be shared between Seller and Purchaser with Seller paying 50% and Purchaser paying 50%.  The allocation of such costs if such Facility is pursued as part of the Site Plan shall be determined by the civil engineer preparing the Site Plan.

(c)             Preparation and Approval of Lot Creation Document .  Concurrently with the preparation of the proposed Century Boulevard CPAP, Purchaser shall cause its civil engineering firm to prepare a boundary line adjustment plat, a subdivision waiver plat or a plat of subdivision (a “ Lot Creation Document ”) sufficient, in form and substance, to permit the Option 2 Parcel and the two future Seller parcels as shown on Exhibit A   as “Future Seller Parcels” to be created as three (3) separate parcels of land that are legally capable of being conveyed by deed and, if Purchaser has elected to construct the Century Boulevard Extension as a public road pursuant to Section 7A(b) , the dedication of the Century Boulevard Extension as a public right-of-way in accordance with the all applicable Legal Requirements, including the Loudoun County subdivision ordinances and also including any associated on or off-site easements required for the approval of such plans and the construction of the improvements shown thereon and on the Approved Concept Development Plan.  The Lot Creation Document shall be prepared in conformity with the Approved Concept Development Plan selected by Purchaser and the proposed Site Plan.  Purchaser shall act in good faith with diligence and continuity in preparing and, if necessary, revising the Lot Creation Document.  Purchaser shall deliver a copy of the proposed Lot Creation Document to Seller at the same time it delivers a copy of the proposed Site Plan and Century Boulevard CPAP pursuant to Section 8(b)(1) so that Seller may determine whether the proposed Lot Creation Document conforms to the Approved Concept Development Plan and the proposed Site Plan.  The provisions of Section 8(b)(1) relating to the review, revision and approval of Purchaser’s proposed Site Plan shall apply to the review, revision and approval of Purchaser’s proposed Lot Creation Document.

(d)             Governmental Approvals .  Within twenty (20) Business Days after Seller approves the Purchaser’s proposed Site Plan, Century Boulevard CPAP, SWM/BMP CPAP Facility, if applicable, and proposed Lot Creation Document, Purchaser shall submit the Seller-approved Site Plan, Century Boulevard CPAP, SWM/BMP CPAP Facility, if applicable, and the Seller-approved Lot Creation Document to the applicable Governmental Authorities for their review and approval, and shall thereafter proceed in good faith with diligence and continuity to obtain from such Governmental Authorities their approval of the proposed Site Plan, Century Boulevard CPAP, SWM/BMP CPAP Facility, if applicable, and the proposed Lot Creation Document.  If a public hearing is held in connection with the proposed Site Plan, Purchaser shall notify Seller promptly after Purchaser receives notice of the date of the hearing, and Seller’s representatives shall have the right to attend, and to present evidence and argument at, the hearing.  If any

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Governmental Authority requires Purchaser to materially modify the Seller-approved Site Plan, Century Boulevard CPAP, SWM/BMP CPAP Facility, if applicable, or the Seller-approved Lot Creation Document, or any of them, Purchaser shall submit the proposed modifications to Seller, identifying modifications from the previously approved submissions.  Purchaser may make material changes only to the extent that such changes are required by the Governmental Authority to comply with Legal Requirements.  Each review by Seller pursuant to this Section 8(d) shall be completed within 10 Business Days after the date of submission of the proposed modifications of the Site Plan, Century Boulevard CPAP, SWM/BMP CPAP Facility, if applicable, or the Lot Creation Document, as the case may be.  If Seller does not notify Purchaser of its determination within the 10-Business Day period, Seller shall be deemed to have approved the proposed modification.

(e)             Seller’s Joinder in Site Plan, Century Boulevard CPAP, SWM/BMP CPAP Facility and Lot Creation Document.   Seller shall join in any required land development applications and similar applications necessary for Purchaser to process the Site Plan, the Century Boulevard CPAP, the SWM/BMP CPAP Facility, if applicable, and the Lot Creation Document.   After the applicable Governmental Authorities have approved the Site Plan, the Century Boulevard CPAP, the SWM/BMP CPAP Facility, if applicable, and the Lot Creation Document, or any of them, Seller shall, to the extent required by Legal Requirements, sign the Site Plan, Century Boulevard CPAP, SWM/BMP CPAP Facility, if applicable, and the Lot Creation Document, including any associated on or off-site easements required for the approval of such plans and the construction of the improvements shown thereon and on the Approved Concept Development Plan   in its capacity as the then-owner of the Property.  Purchaser shall, at its cost and expense and without reimbursement from Seller, cause the Lot Creation Document to be delivered to the Escrow Agent at Closing for recording among the Land Records of Loudoun County, Virginia, but the Lot Creation Document shall not be recorded unless the Closing is consummated pursuant to the provisions of this Agreement.

(f)             Preparation of Plans and Specifications .  Within 20 Business Days after the applicable Governmental Authorities have approved the Site Plan, the Century Boulevard CPAP, the SWM/BMP CPAP Facility, if applicable, and the Lot Creation Document, Purchaser shall prepare plans, specifications and working drawings (collectively, the “ Building Plans ”) for the Phase 1 Building.  The Building Plans shall be prepared by Kishimoto Gordon or another firm of architects selected by Purchaser and approved by Seller.  The Building Plans are sometimes referred to in this Agreement as the “ Construction Plans .”  The Construction Plans shall be prepared in conformity with the Approved Concept Development Plan and the approved Site Plan, shall comply with all applicable Legal Requirements and shall be in sufficient detail to qualify for submission to the applicable Governmental Authorities for a building permit.  Purchaser shall deliver a copy of its proposed Construction Plans to Seller within 20 Business Days after the date on which the Site Plan is approved by the applicable Governmental Authorities so that Seller may determine whether the Construction Plans conform to the Approved Concept Development Plan.  Seller shall not unreasonably withhold, delay or condition its approval of the Purchaser’s proposed Construction Plans, provided they are

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prepared in conformity with the Approved Concept Development Plan and otherwise comply with the requirements of this Section 8(f) .  If Seller determines that the proposed Construction Plans do not conform to the Approved Concept Development Plan or the other requirements of this Section 8(f) , Seller shall so notify Purchaser, specifying in what respects the proposed Construction Plans do not so conform, and Purchaser shall revise the Construction Plans to so conform it and shall resubmit the revised Constructions Plans to Seller for review for that purpose.  Purchaser and Seller shall act in good faith with diligence and continuity in preparing, reviewing and, if necessary, revising the Construction Plans.  The initial review by Seller of the proposed Construction Plans shall be completed within 10 Business Days after they are submitted by Purchaser and any subsequent review by Seller of any revisions thereto shall be completed within 10 Business Days after Purchaser’s submission of such revision.  In case of resubmissions or revisions, Seller may not disapprove any matter previously submitted and approved by Seller, except to the extent that such resubmission or revision affects any matter previously approved or deemed approved.  If Seller does not notify Purchaser of its determination within 10-Business Day period, as the case may be, Seller shall be deemed to have determined that the proposed Construction Plans or any revision thereof conform to the Approved Concept Development Plan.

(g)             Compliance with Legal Requirements .  Purchaser is responsible for ensuring that the Site Plan, the Century Boulevard CPAP, the SWM/BMP CPAP Facility, if applicable, the Lot Creation Document and the Construction Plans comply with all applicable Legal Requirements.  Seller’s determination that the Site Plan, the Lot Creation Document and the Construction Plans, or any of them, meet the standards for conformity required by Section 8(a) , Section 8(b) , Section 8(c) and Section 8(f) shall not be, nor be construed as being, nor be relied upon as, a determination that the Site Plan, the Century Boulevard CPAP, the SWM/BMP CPAP Facility, if applicable, the Lot Creation Document or the Construction Plans comply with Legal Requirements.

(h)             Filing for Building Permit .  Within 10 Business Days after Seller approves the Purchaser’s Construction Plans, Purchaser shall submit the Seller-approved Construction Plans to the applicable Governmental Authorities for their review and approval and shall apply for all permits required to permit Purchaser to commence construction of the improvements described in the Seller-approved Constructions Plans (collectively, the “ Building Permit ”).  Purchaser shall thereafter proceed in good faith with diligence and continuity to obtain from such Governmental Authorities their approval of the proposed Construction Plans and the issuance of the Building Permit.  Seller, as the record owner of the Land and the portion of the Overall Property on which the Century Boulevard Extension is located shall join with Purchaser in signing applications for the Building Permit to the extent such joinder is required by law.

(i)             Costs and Expenses .  Purchaser, at its own expense and without reimbursement from Seller, will pay all fees and reimbursable expenses of its architects and civil engineers and all other costs and expenses of preparing the Site Plan, the Century Boulevard CPAP, the Lot Creation Document, the Construction Plans and obtaining the applicable Governmental Authorities’ approval of those documents and the issuance of the Building Permit.  The cost of preparing the SWM/BMP CPAP Facility, if

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applicable, shall be shared between Seller and Purchaser as provided for in Section   8(a) hereof, with Seller to reimburse to Purchaser its pro rata share of such costs within thirty (30) days of its receipt of invoice therefor, including any supporting invoices from the applicable civil engineer or other consultant.

(j)             Seller’s Termination Rights .  This Agreement may be terminated by Seller by giving written notice to Purchaser and the Escrow Agent if:

(1)           Purchaser fails to comply with the time requirements set forth in Section 8 hereof, provided such failure continues for more than thirty (30) days following Seller's notice to Purchaser of such failure, subject to force majeure.

(2)           Purchaser does not consummate the purchase of the Property on or before the earlier to occur of (i) September 30, 2009, or (ii) 540 days after the Due Diligence Termination Date.

(k)           Effect of Seller’s Termination .  If Seller terminates this Agreement pursuant to Section 8(j) , this Agreement shall become null and void, no party shall have any further liability or obligation to any other party under this Agreement, except for Purchaser’s Surviving Obligations and the Escrow Agent shall pay $250,000 of the Deposit to Seller and the Escrow Agent shall pay the balance of the Deposit to Purchaser.  Seller’s sole and exclusive remedy for Purchaser’s failure to perform its obligations under this Section 8 shall be to receive the $250,000 of the Deposit as liquidated damages.

(a)            Representations and Warranties True .  The representations and warranties made by Seller in Section 5 shall be true and correct in all material respects on and as of the Closing Date with the same force and effect as if such representations had been made on and as of the Closing Date.  The Seller’s Closing Certificate shall not disclose that any of Seller’s representations and warranties in   Section 5 is untrue or incorrect in any material respect as of the date of such certificate as if such representations and warranties were made on and as of the date of such certificate.

(b)            Seller’s Performance .  Seller shall have performed all covenants and agreements required by this Agreement to be performed by it on or before the Closing Date.

(c)            Title to Property .  On the Closing Date, (i) Seller’s title to the Property shall be marketable, good of record and in fact, and free and clear of all mortgages, liens, encumbrances, easements, leases, conditions and other matters affecting title other than only the Permitted Exceptions, and (ii) the Title Company shall be unconditionally obligated and prepared, subject to the payment of the applicable title insurance premium and other related charges, to issue to Purchaser an ALTA extended coverage owner’s title insurance policy (1992 form) for the Property in compliance with the Title Commitment

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(including such endorsements as Purchaser may reasonably require), together with such reinsurance and direct access agreements as may be reasonably required by Purchaser.

(d)            Zoning .  There shall have been no change in the zoning classification or the zoning ordinances or regulations affecting the Land from those existing as of the Due Diligence Termination Date which would preclude or impair the continuing use of the Property for purposes contemplated by the Approved Concept Development Plan.

(e)            No Violations .  All written notices of violations of governmental orders or requirements noted or issued by any applicable Governmental Authority, and any action by any Governmental Authority in court against or affecting the Property, which would have an adverse impact on Seller's ability to convey the Property to Purchaser or on Purchaser's ability to acquire the Property and develop the same as contemplated by the Approved Concept Development Plan shall have been complied with by Seller or the Property shall no longer be subject thereto, except to the extent such matter results for the actions of Purchaser on the Property.

(f)            No Tenants or Occupants .  On the Closing Date, the Land shall be free of all tenants and lessees and no Person (other than Purchaser) shall have any right or option to purchase all or any portion of the Land from Seller.

(g)            No Physical Change .  Between the Effective Date and the Closing Date there shall not have occurred any material change in the physical condition of the Property, except for changes, if any, caused by Purchaser's studies and tests.

(h)            Site Plan, Century Boulevard CPAP, SWM/BMP CPAP Facility (if applicable), Lot Creation Documents, Construction Plans and Building Permit .  On or before the Closing Date, the applicable Governmental Authorities shall have approved the Site Plan, the Century Boulevard CPAP, the SWM/BMP CPAP Facility (if applicable) and the Lot Creation Documents (including any dedication to public use of the Century Boulevard Extension, if applicable), and all on and off-site easements for the development of the Property provided for in or needed for the development contemplated by the Approved Concept Development Plan shall have been recorded.

(i)            Seller’s Reserved Easement for Future Construction of SWM/BMP Facility .  If Purchaser elects pursuant to Section 3A(f) to develop and construct improvements on the Land utilizing the Non-Pond Concept Development Plans, on or before the Due Diligence Termination Date Seller and Purchaser shall have agreed on the form and substance of an easement agreement pursuant to which Seller will reserve, at the Closing, an easement over and across the Land for purposes of its future construction of the SWM/BMP Facility during the Pond Construction Option Period, including the general parameters of and the physical appearance of any storm water pond to be constructed at a later date, the spillway and surrounding landscaping, Purchaser’s right, if any, to make aesthetic upgrades to such Facility and the monetary contribution to be made by Purchaser to Seller for the cost of any such upgrades requested by Purchaser (the “ Pond Easement Agreement ”).  If the Purchaser elects to develop and construct improvements on the Land utilizing the Pond Concept Development Plans, the Pond

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Easement Agreement shall grant Seller the non exclusive right in common with Purchaser to utilize the SWM/BMP Facility to satisfy Seller’s and Purchaser’s stormwater management and BMP requirements for the Property, the Overall Property and Dulles Town Center project generally including granting easements to the applicable Government Authority and upgrading/retrofitting such facility, provided Purchaser restores such facility and any associated landscaping to the quality that existed prior to such disturbance.

(j)            Contribution for Cost of Construction of SWM/BMP Facility .  On or before the Due Diligence Termination Date, Seller and Purchaser shall have agreed, in writing, on the amount and timing of a reasonable contribution to be made by Seller or Purchaser, as applicable, toward the cost of the SWM/BMP Facility.  If Purchaser constructs the SWM/BMP Facility during the Pond Construction Reimbursement Period, Seller shall make a contribution to the costs of designing and constructing such Facility with the general parameters of Seller’s contribution being the amount such Facility would have cost Seller to design and construct if Seller were to construct such Facility solely to accommodate Seller’s Retained Property or other property within the larger Dulles Town Center project, whether or not owned by Seller, but excluding (i) the property to be acquired by Purchaser, and (ii) any property of Seller that will not utilize such Facility to satisfy its stormwater management or BMP requirements.  If Seller constructs the SWM/BMP Facility during the Pond Construction Reimbursement Period, Purchaser shall make a contribution to the costs of designing and constructing such Facility with the general parameters of Purchaser’s contribution being the amount such Facility would have cost Purchaser if Purchaser were to design and construct such Facility solely to accommodate the undeveloped areas on the Property that is subject to future development by Purchaser.  For purposes of this pro ration, it shall be a rebuttable presumption that any development by Purchaser prior to Seller’s construction of the SWM/BMP Facility would have provided its own stormwater management and BMP facilities.  It is anticipated that the timing of the payment to be made by Seller or Purchaser, as applicable would be when Seller or Purchaser, as applicable would have otherwise been required to develop the SWM/BMP Facility, but at a minimum on a site plan by site plan basis as development occurs that will drain into such SWM/BMP Facility.  Such agreement shall also establish prorata contributions for the maintenance of such facility.  Seller’s and Purchaser’s agreement relating to the matters referred to in Section 9(i) and Section 9(j) will be included in the Proffer Allocation and Infrastructure Agreement.

(k)            Proffer Allocation and Infrastructure Agreement .  On or before the Due Diligence Termination Date, Seller and Purchaser shall have agreed on the form and substance of the Proffer Allocation and Infrastructure Agreement.

(l)            Architectural Review Board Approval .  On or before the Effective Date, the architectural review board under the Property Owners Association Covenants shall have approved the elevations for, and the exterior materials to be used in the construction of, Purchaser’s Phase 1 Building as shown on the Approved Concept Development Plan, Exhibit A and Exhibit G.   The standard for such review and approval shall be that such building and exterior materials shall be consistent in terms of quality with the other office buildings developed by Seller (or its Affiliates) within the Dulles Town Center Project

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and is otherwise compatible with development within the office portion Dulles Town Center project.  Compatible does not necessarily mean that such building design will be similar in style to Seller's other buildings within the project and both Seller and Purchaser understand that architectural design should evolve over time.  Seller’s execution hereof confirms that the ARB has given the approval contemplated above.  Seller hereby represents that the architectural review board under the Property Owner’s Association Covenants has approved the elevations for, and the exterior materials to be used in the construction of, Purchaser’s Phase 1 Building as shown on the Approved Concept Development Plan, Exhibit A and Exhibit G .

(m)            Century Boulevard Easement Agreement .  On or before the Due Diligence Termination Date, Seller and Purchaser shall have agreed on the form and substance of the Century Boulevard Easement Agreement.

(a)            Purchaser’s Performance .  The Purchaser shall have performed all covenants and agreements required by this Agreement to be performed by it on or before the Closing Date.

(b)            Notice to Proceed .  On the Closing Date, Purchaser shall deliver to Seller a copy of a Notice to Proceed issued by Purchaser to its general contractor authorizing such general contractor to commence construction of the Century Boulevard Extension, immediately after the Closing, and Purchaser shall issue and deliver to Seller a Notice to Proceed for the construction of an office building containing at least 120,000 square feet of gross floor area ninety (90) days following building permit.

(c)            Pond Easement Agreement .  On or before the expiration of the Due Diligence Termination Date, Seller and Purchaser shall have agreed on the form and substance of the Pond Easement Agreement.

(d)            Proffer Allocation and Infrastructure Agreement .  On or before the Due Diligence Termination Date, Seller and Purchaser shall have agreed on the form and substance of the Proffer Allocation and Infrastructure Agreement.

(e)            Century Boulevard Easement Agreement .  On or before the Due Diligence Termination Date, Seller and Purchaser shall have agreed on the form and substance of the Century Boulevard Easement Agreement.

(f)            Contribution for Cost of Construction of SWM/BMP Facility .  On or before the Due Diligence Termination Date, Seller and Purchaser shall have agreed, in writing, on the amount and timing of a reasonable contribution to be made by Seller to Purchaser, or by Purchaser to Seller, toward the cost of the SWM/BMP Facility.  The requirements for, and the general parameters of, the Seller’s or the Purchaser’s contribution is described in Section 9(j) .

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(a)            Closing Date and Escrow .  The closing of the purchase and sale of the Property (the “ Closing ” ) shall occur on the latest to occur of (i) the 20 ^th day after the date on which the applicable Governmental Authorities approve the Century Boulevard CPAP (or, if the 20 ^th day is not a Business Day, on the first Business Day thereafter), (ii) the 20 ^th day after the date on which the applicable Governmental Authorities approve the Lot Creation Document (or, if the 20 ^th day is not a Business Day, on the first Business Day thereafter), or (iii) January 9, 2009, with time being of the essence,.  Seller and Purchaser may, by mutual agreement, agree to hold the Closing at an earlier date.  The Closing shall be held at the office of the Escrow Agent, or at any other location in Fairfax or Loudoun County, Virginia, approved by Seller and Purchaser.  The date on which the Closing occurs is referred to in this Agreement as the “ Closing Date .”  On or before Noon, local time, on the Closing Date, Purchaser shall cause to be deposited with the Escrow Agent immediately available funds in an amount equal to the sum of the Purchase Price and the costs, expenses, prorations and adjustments payable by Purchaser under this Agreement, reduced by (x) the amount of the Deposit, and (y) the net amount of the prorations and adjustments for which Purchaser receives credit, if any, on the Closing Statement (defined in Section 11(d) ).  If (1) Seller and Purchaser have each notified the Escrow Agent that all conditions precedent to the other party’s performance have been satisfied or waived (other than the respective covenants and obligations of Seller and Purchaser to be performed on the Closing Date), (2) the Escrow Agent has received the funds from Purchaser in accordance with the preceding sentence, (3) the Escrow Agent has received the documents and instruments to be delivered by Seller pursuant to Section 11(b) , and (4) the Escrow Agent has received the documents and instruments to be delivered by Purchaser pursuant to Section 11(c) , then the Escrow Agent shall, not later than 3:00 p.m., local time, on the Closing Date, (i) record the Lot Creation Document, the Deed, the Repurchase Option Agreement, the Pond Easement Agreement, the Century Boulevard Easement Agreement (if applicable), the Proffer Allocation and Infrastructure Agreement and the Pre-Emptive Option Agreement, in that order, in the applicable land records, (ii) disburse to Seller an amount equal to the Purchase Price, reduced by the Deposit and the costs, expenses, prorations and adjustments payable by Seller under this Agreement and increased by the amount of the prorations and adjustments for which Seller receives credit on the Closing Statement, (iii) deliver to Purchaser the documents and instruments referred to in Section 11(b) and all other documents and instruments received by it which, in accordance with the terms of this Agreement, are to be delivered by Seller to Purchaser on the Closing Date, (iv) deliver to Seller the documents and instruments referred to in Section 11(c) and all other documents and instruments received by it which, in accordance with the terms of this Agreement, are to be delivered by Purchaser to Seller on the Closing Date, and (v) make the other disbursements and deliveries required by the Closing Statement.  On the Closing Date, immediately after receiving confirmation that the Deed has been recorded, the Escrow Agent shall disburse the Deposit to Seller.

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(b)            Seller’s Deliveries .  On the Closing Date, Seller shall deliver to Purchaser the following documents with respect to the Property:

(1)           the Lot Creation Document in the form approved by the applicable Governmental Authorities, signed by Seller, in recordable form (if not previously recorded);

(2)           the Deed signed by Seller, in recordable form, vesting fee simple title to the Property in Purchaser;

(3)           a certificate signed by Seller, dated as of the Closing Date (the “ Seller’s Closing Certificate ”), certifying to Purchaser that all of Seller’s representations and warranties in Section 5 are true and correct as of the date of such certificate as if such representations and warranties were made on and as of the date of such certificate or, if and to the extent any of such representations and warranties is not so true and correct, identifying with reasonable particularity the nature and extent to which any such representation or warranty is not so true and correct;

(4)           a certification of Seller’s non-foreign status which complies with the provisions of Section 1445(b)(2) of the Internal Revenue Code of 1986, as amended, any regulations promulgated thereunder, and any revenue procedures or other officially published announcements of the Internal Revenue Service or the U.S. Department of the Treasury in connection therewith, signed by Seller;

(5)           the Closing Statement, signed by Seller;

(6)           an Owner’s Affidavit signed by Seller, addressed to the Title Company, with respect to the absence of claims which would give rise to mechanics’ liens, the absence of parties in possession of the Property and the absence of unrecorded easements granted by Seller, in the form required by the Title Company to eliminate the exceptions for those matters from Purchaser’s title insurance policy;

(7)           affidavits and other instruments, including Seller’s Organizational Documents, and good standing certificates reasonably requested by Purchaser and the Title Company, evidencing the power and authority of Seller to enter into this Agreement and to consummate the transactions contemplated by this Agreement;

(8)           one counterpart of each of the Repurchase Option Agreement, the Pond Easement Agreement, the Century Boulevard Easement Agreement, (if applicable) the Proffer Allocation and Infrastructure Agreement and the Pre-Emptive Option Agreement signed by the Seller in recordable form; and

(9)           such other documents as may be required by this Agreement or as may reasonably be required to carry out the terms and intent of this Agreement.

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(c)            Purchaser’s Deliveries .  On the Closing Date, Purchaser shall pay the Purchase Price pursuant to Section 11(a) , and shall deliver to Seller the following documents with respect to the Property:

(1)          one counterpart of each of the Repurchase Option Agreement, the Pond Easement Agreement, the Century Boulevard Easement Agreement (if applicable), the Proffer Allocation and Infrastructure Agreement and the Pre-Emptive Option Agreement signed by the Purchaser in recordable form; and

(2)           the Closing Statement.

(d)            Apportionments .  All real estate taxes (including assessments made by reason of the fact that the Property is located in any special taxing district or within a community development authority) relating to the Property shall be paid or shall be prorated between Seller and Purchaser as of the Closing Date.  For purposes of this proration, Purchaser shall be deemed to own the Property and therefore be responsible for the real estate taxes and assessments for the entire Closing Date.  If the Closing Date shall occur before the tax rate or assessment is fixed for the tax year in which the Closing Date occurs, the apportionment of taxes shall be upon the basis of the tax rate or assessment for the immediately preceding tax year applied to the latest assessed valuation and Seller and Purchaser shall readjust real estate taxes promptly after the determination of the tax rate or assessment for the tax year in which the Closing Date occurs (with such obligation to survive the Closing).  Any apportionments and prorations which are not expressly provided for in this Section shall be made in accordance with the customary practice in Loudoun County, Virginia.  On or before the Closing Date, Seller and Purchaser shall jointly prepare a schedule showing the Purchase Price, the Deposit, the adjustments and prorations and the expenses to be paid by Seller and Purchaser pursuant to this Agreement (the “ Closing Statement ”).  Any net adjustment in favor of Purchaser shall be credited against the Purchase Price on the Closing Date.  Any net adjustment in favor of Seller shall be paid in cash or cash equivalent on the Closing Date by Purchaser to Seller.  A copy of the Closing Statement agreed upon by Seller and Purchaser shall be signed by Seller and Purchaser and delivered to the Escrow Agent on the Closing Date.

(e)            Delivery in Escrow .  The delivery to the Escrow Agent of the Purchase Price, the executed Deed and all other documents, instruments and other payments required to be delivered or paid by either party to the other by the terms of this Agreement shall be deemed to be a good and sufficient tender of performance of the terms hereof.  The Escrow Agent shall have the right, at the Closing, to apply the Purchase Price to pay off and discharge encumbrances or other obligations affecting the Property which are not Permitted Exceptions, so that title to the Property shall be insurable as required by Section 9(c) .

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of the Deed and the Repurchase Option Agreement.  Purchaser and Seller shall each pay one-half (1/2) of the Escrow Agent’s fee and all other charges and expenses which arise in connection with the Closing.

(a)            Reasons for Termination .  This Agreement may be terminated upon written notice given to the Escrow Agent and the other party hereto by:

(1)           Purchaser pursuant to Section 13(b) , if any one or more of the conditions set forth in subsections (a) through (h) of Section 9 is not satisfied on the Closing Date; or

(2)           Seller pursuant to Section 13(c) , if any one or more of the conditions set forth in subsections (a) or (b) of Section 10 is not satisfied on the Closing Date.

Seller’s right to terminate this Agreement pursuant to this Section is in addition to Seller’s right to terminate this Agreement pursuant to Section 8(j) .  If Seller terminates this Agreement pursuant to Section 8(j) , the provisions of that Section , and not the provisions of Section 13(c) shall control the disposition of the Deposit.

(b)            Termination by Purchaser .  If Purchaser terminates this Agreement pursuant to Section 13(a)(1) , then this Agreement shall be null and void, Escrow Agent shall return the Deposit to Purchaser and no party shall have any further liability or obligation to any other party under this Agreement, except for Purchaser’s Surviving Obligations, and except that if Purchaser terminates this Agreement pursuant to Section 13(a)(1) because of a breach by Seller of the representations and warranties made by Seller in Section 5 or the willful failure of Seller to perform any of the covenants or agreements to be performed by it under this Agreement, or the failure of Seller to make full settlement when obligated to do so under this Agreement, Purchaser may sue to recover its damages arising out of such breach or nonperformance, but Seller’s liability for damages for a misrepresentation or warranty discovered prior to Closing shall be subject to the limitation contained in Section 5(k)(4) .

(c)           Termination by Seller .  If Seller terminates this Agreement pursuant to Section 13(a)(2) , this Agreement shall become null and void, no party shall have any further liability or obligation to any other party under this Agreement, except for Purchaser’s Surviving Obligations, and the Escrow Agent shall pay the Deposit to Seller.  Seller’s sole and exclusive remedy for Purchaser’s default shall be to receive the Deposit as liquidated damages, and in no event and under no circumstances shall Seller be entitled to receive more than the Deposit as damages for Purchaser’s default.  THE PARTIES AGREE THAT IT WOULD BE IMPRACTICABLE AND EXTREMELY DIFFICULT AT THE TIME OF MAKING THIS AGREEMENT TO ESTIMATE THE DAMAGES WHICH SELLER MAY SUFFER BY REASON OF ANY DEFAULT BY PURCHASER IN THE TIMELY PERFORMANCE OF ITS OBLIGATION TO PURCHASE THE PROPERTY AS PROVIDED FOR HEREIN, INCLUDING THE

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PERFORMANCE OF ITS OBLIGATIONS UNDER SECTION 8 .  THE PARTIES HERETO FURTHER AGREE THAT THEIR BEST ESTIMATE, BASED ON ALL RELEVANT FACTS, OF THE TOTAL DAMAGE AND EXPENSES THAT SELLER WOULD SUFFER IN THE EVENT OF ANY DEFAULT IN THE TIMELY PERFORMANCE OF PURCHASER’S OBLIGATION TO PURCHASE THE PROPERTY, IS AND SHALL BE IN AN AMOUNT EQUAL TO THE DEPOSIT AND ALL INTEREST ACCRUED THEREON. ACCORDINGLY, SUBJECT TO THE CONDITIONS FOR PURCHASER’S BENEFIT SET FORTH IN THIS AGREEMENT, IN THE EVENT PURCHASER DEFAULTS IN THE TIMELY PURCHASE OF THE PROPERTY IN ACCORDANCE WITH THE TERMS OF THIS AGREEMENT, UNLESS SELLER IS THEN IN DEFAULT HEREUNDER, SELLER SHALL BE RELEASED FROM ITS OBLIGATION TO SELL THE PROPERTY TO PURCHASER AND SELLER SHALL BE ENTITLED AS ITS SOLE AND EXCLUSIVE REMEDY TO RETAIN THE DEPOSIT AND ALL INTEREST ACCRUED THEREON.  SELLER AND PURCHASER HAVE EACH PLACED THEIR INITIALS IN THE SPACES BELOW TO INDICATE THAT THEY HAVE READ, UNDERSTAND AND AGREE TO THIS LIQUIDATED DAMAGES PROVISION.

(d)            Purchaser’s Right to Seek Specific Performance .  If Seller defaults in performing any covenants or agreements to be performed by Seller under this Agreement, Purchaser shall have the right, instead of terminating this Agreement pursuant to Section 13(a) , to elect to permit this Agreement to remain in effect and, in addition to the remedies set forth in Section 13(b) , to seek specific performance of Seller’s obligation to sell the Property to Purchaser, subject to the limitation that no suit for specific performance may be filed or commenced by Purchaser more than 180 days after the otherwise required Closing Date.

(e)            Special Termination Provisions .

(1)           If any one or more of the conditions set forth in Section 9(i) , Section 9(j) , Section 9(k) or Section 9(m) is not satisfied on or before the Due Diligence Termination Date, the Purchaser shall have the right to terminate this Agreement by giving written notice of termination to the Seller and the Escrow Agent at any time after the Due Diligence Termination Date and before the date on which all of the conditions set forth in Section 9(i) , Section 9(j) , Section 9(k) and Section 9(m) are satisfied.

(2)           If any one or more of the conditions set forth in Section 10(c) , Section 10(d) , Section 10(e) or Section 10(f) is not satisfied on or before the Due Diligence Termination Date, the Seller shall have the right to terminate this Agreement by giving written notice of termination to the Purchaser and the Escrow Agent at any time after the Due Diligence Termination Date and before

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the date on which all of the conditions set forth in Section 10(c) , Section 10(d) , Section 10(e) and Section 10(f) are satisfied.

(3)           If Purchaser or Seller terminates this Agreement pursuant to Section 13(e)(1) or Section 13(e)(2) , then this Agreement shall be null and void, Escrow Agent shall return the Deposit to Purchaser and no party shall have any further liability or obligation to any other party under this Agreement, except for Purchaser’s Surviving Obligations, provided before a party can terminate this Agreement pursuant to Section 13(e), the party desiring to terminate the Agreement shall first deliver to the other party a form of agreement satisfactory to the delivering party to satisfy the conditions set forth in sections 9(i), 9(j), 9(k), 9(m), 10(c), 10(d), 10(e) or 10(f) (or for any of such conditions that remain unsatisfied), including delivering a certificate that such agreement(s) have been prepared in good faith based on the terms of this Agreement.  If within ten (10) business days of the receiving party’s receipt of such agreement(s), it agrees in writing to the form of such agreement(s), then neither party shall have the ability to terminate this Agreement based on the condition precedent applicable to such agreement.

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facsimile or (c) recognized overnight national courier service shall be deemed to have been received by such party at the time the notice is delivered to such party’s designated address.

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FRXLIB-535778.1-BFTOMPKI

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NATIONAL RURAL UTILITIES COOPERATIVE FINANCE CORPORATION

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By: /s/ ROBERT M.GORDON

Name: Robert M. Gordon 

Title: Pre siden t

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