4. Additional Payments. Landlord, pursuant to that certain (i) amendment to GSA’slease dated April 13, 2007 (“**SLA 12”**) (a copy of which is attached hereto as Exhibit A-1),(ii) amendment to GSA’s lease dated May 7, 2007 (“**SLA 13**”) (a copy of which is attached hereto asExhibit A-2) and (iii) amendment to GSA’s lease being executed contemporaneously herewith(the “**New SLA”**(a copy of which is attached hereto as Exhibit A-3), together with SLA 12and SLA 13, the “**SLAs**”), is entitled to receive the additional payments listed below in excess ofGSA’s current base rent and additional rent obligations (the “**Additional Payments**”). If and onlyif Landlord actually receives any such payment, Landlord will deliver such payments to Tenantwithin five (5) business days of Landlord’s actual receipt of such payment or, in the case of theMay 1 and June 1 payments, within five (5) business days of the date hereof. If Landlord actuallyincurs any out-of-pocket costs attributable to its efforts to collect the Additional Payments below(including without limitation reasonable attorneys’ fees), Landlord may withhold and deduct suchcollection costs from the Additional Payments before delivering the Additional Payments to Tenant,provided, however, that in the event such collection efforts seek to recover payment of base rent,additional rent or other payment obligations of GSA in addition to the Additional Payments, theout-of-pocket collection costs deducted by Landlord will be pro-rated based upon the ratio of theAdditional Payments to the total amount sought by Landlord. Landlord shall have no liability forGSA’s failure to timely make any of the Additional Payments set forth herein, Tenant hereby waivingany right it may have against Landlord for such failure by GSA, provided that nothing in thissentence shall be construed to release Landlord from Landlord’s obligations to Tenant under theterms of this Amendment. Landlord and Tenant acknowledge that the payments contemplated onNovember 1, 2007, and December 1, 2007, are contingent on GSA remaining in the Premises beyond thedates specified in Section 5 of the New SLA, as further set forth in the New SLA.   May 1, 2007 $100,000June 1, 2007 $150,000August 1, 2007 $200,000September 1, 2007 $200,000October 2, 2007 $750,000November 1, 2007 $400,000 (only made if GSA has not vacated the Premises by October 2, 2007)December 1, 2007 $500,000 (only made if GSA has not vacated the Premises by November 1, 2007)     (a) Landlord shall use all commercially reasonable efforts to collect Additional Payments fromGSA and such obligation to collect Additional Payments shall survive termination of the Lease withrespect to those Additional Payments which accrue prior to the effective date of termination of theLease. In the event that any Additional Payment from GSA is late, Landlord shall use reasonableefforts to notify Tenant of the circumstances surrounding such non-payment within two (2) businessdays after the Additional Payment due date. Provided Tenant is not in default under the Leasebeyond the expiration of any applicable notice and/or cure period, Landlord shall not enter intoany amendment to the GSA lease or other agreement which reduces, delays or forgives any of theAdditional Payments without Tenant’s prior written consent, which may be granted or withheld inTenant’s sole discretion. Landlord represents that
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as of the date hereof it has not entered into any agreement which would reduce, delay orforgive any of the Additional Payments.     5. Termination Period; Cure Period. The end of the period for Tenant’s one-timetermination option set forth in Section 3.2(i) of the Lease is extended from September 30,2007 to 5:00 p.m. (eastern time) on November 30, 2007. Accordingly, (a) the date “September 30,2007” in the first sentence of Section 3.2(i) of the Lease is deleted and replaced with“November 30, 2007,” and (b) the phrase “before 5:00 (eastern time) on September 30, 2007” in thefourth sentence of Section 3.2(i) is deleted and replaced with the phrase “before 5:00 p.m.(eastern time) on November 30, 2007.” In addition, the Cure Period as set forth in Section3.2(i) of the Lease is extended until the later of (i) ten (10) business days after Landlord’sreceipt of Tenant’s timely notice of termination in accordance with the terms of Section3.2(i) (if any) and (ii)11:59 p.m. (eastern time) on November 30, 2007. Accordingly, thesecond sentence of Section 3.2(i) of the Lease is deleted and replaced with the followingsentence, “Notwithstanding the foregoing termination right set forth in this Subsection (i), ifLandlord on or before the later of (i) ten (10) business days after Landlord’s receipt of Tenant’stimely notice of termination in accordance with the terms of Section 3.2(i) (if any) and(ii) 11:59 p.m. (eastern time) on November 30, 2007 (the “**Cure Period**”) delivers the Floors inReady Condition, Tenant shall accept the Floors and its termination will not be effective, providedthat if at any time during the Cure Period Landlord delivers notice to Tenant that it is unable todeliver the Floors, Tenant’s termination will be effective as of the date of receipt of such noticefrom Landlord.” By way of example only of the foregoing terms of this Section 5, if Tenanttimely and properly delivers a termination notice to Landlord on September 15, 2007, and Landlordsubsequently delivers the Floors in the Ready Condition on November 30, 2007, Tenant’s terminationwill not be effective and the Lease will remain in full force and effect.     6. Other Payments. If Landlord receives amounts or sums in excess of or in additionto the Additional Payments set forth in Section 4 above, Landlord shall not be required to deliverto Tenant such excess amounts, payments or sums from GSA to Landlord, notwithstanding the fact thatother Additional Payments may subsequently become due. By way of example only, if on August 1,2007, GSA pays to Landlord $240,000, then Landlord shall as set forth in Section 4 above, deliver$200,000 to Tenant as part of the Additional Payments, and $40,000 will remain with the Landlord.Landlord and Tenant acknowledge that the Additional Payments are in excess of GSA’s current rentalobligations under their lease (i.e., those obligations prior to the execution of the SLAs)(the “**Current GSA Rent**”). Accordingly, Landlord and Tenant agree that if for any reason Landlorddoes not receive, or GSA does not otherwise pay all or any portion of the Additional Payments,Landlord will not be required to pay any such Additional Payments to Tenant from GSA’s rentalobligations under the lease between Landlord and GSA, provided, however, that if any AdditionalPayments are late, any payments by GSA to Landlord in excess of the Current GSA Rent shall be firstpaid to Tenant until the late Additional Payments have been paid.     7. Tenant’s Rent Abatement. Because Tenant may need to extend the lease for all or aportion of the space it currently occupies pursuant to Tenant’s Existing Lease (“**Tenant’sExtension**”) due to extension of the Anticipated Delivery Date, Landlord has agreed to provide
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certain abatements in connection with Tenant’s Extension as well as its extension of the termthereof prior to the date of this Amendment (“**Tenant’s Rent Abatement”**), as further set forth andin accordance with the terms of Section 3.2(d) of the Lease (as such Section 3.2(d) of theLease is modified by the terms of this Amendment). In consideration of such abatement and theamounts Landlord agrees to pass through to Tenant hereunder, Tenant agrees to use the “extensioncost reduction efforts” (as defined below) to mitigate and reduce its obligations (includingwithout limitation rent and additional rent) to its current landlord arising from Tenant’sExtension, including without limitation, attempting to (i) sublease, license and/or assign itsobligations under Tenant’s Existing Lease after Tenant vacates its existing premises (the “**1899 LSpace**”), (ii) obtain an early termination of Tenant’s Existing Lease or to cause its landlord torelease Tenant prior to the end of Tenant’s Extension, and/or (iii) otherwise reduce its financialobligations under Tenant’s Existing Lease during Tenant’s Extension. As used herein, the phrase“extension cost reduction efforts” shall mean Tenant’s obligation to make good faith efforts tonegotiate a financial settlement with its current landlord and/or to retain and engage a leasingbroker to attempt to find a short-term sublease, subject to the terms of its lease with its currentlandlord. Nothing in this Amendment shall (i) restrict Tenant from entering into a Tenant’sExtension or (ii) require Tenant to enter into a sublease, license or assignment agreement uponterms which are not acceptable to Tenant in its reasonable discretion.          (a) If during any period that Tenant’s Rent Abatement occurs, Tenant assigns, licenses orsubleases all or any portion of the 1899 L Space leased by Tenant pursuant to Tenant’s Extension,then no later than the earliest to occur of (i) thirty (30) days after the expiration of suchassignment or sublease and (ii) five (5) business days after the day Tenant determines the finalincome from such assignment, license or sublease net only of its actual out-of-pocket brokeragecosts, reasonable attorney fees and other third-party out-of-pocket costs incurred directly withsuch assignment, sublease or license (the “**Assignment/Sublease Value**”), Tenant shall notifyLandlord of the Assignment/Sublease Value and Tenant’s Rent Abatement during the first Lease Yearshall be reduced by an amount equal to one-half (1/2) of the Assignment/Sublease Value (the“**Abatement Reduction**”), applied first to the last amounts of rent abatement due Tenant during thefirst Lease Year. In the event that all of Tenant’s Rent Abatement during the first Lease Year hasalready been utilized at the time of such determination, the Abatement Reduction shall be appliedto the last amounts of rent abatement due Tenant during the second Lease Year.          (b) If at any time Tenant terminates all or any portion of its obligations under Tenant’sExisting Lease (as extended by Tenant’s Extension) prior to the scheduled expiration of Tenant’sExisting Lease (as extended by Tenant’s Extension) by paying an early termination or equivalentfee, Tenant’s Rent Abatement shall continue to accrue to Tenant’s benefit pursuant to the terms ofthe Lease, but shall cease to accrue to Tenant’s benefit at such time as the total amount ofTenant’s Rent Abatement accruing under the Lease from and after the effective date of suchtermination is equal to one-half (1/2) of such early termination or equivalent fee. If at any timeTenant’s obligations under Tenant’s Extension are terminated for any reason prior to the scheduledexpiration thereof, including without limitation for condemnation or casualty, and there is noearly termination or equivalent fee, Tenant’s Rent Abatement shall cease to accrue to Tenant’sbenefit simultaneously with such termination of Tenant’s obligations under Tenant’s Extension. Byway of example only, if at the end of month five (5) of Tenant’s Extension,
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Tenant pays its landlord an early termination fee of $100,000, the Tenant’s Rent Abatementwould continue to accrue until the total amount of Tenant’s Rent Abatement accruing from and afterthe end of month five (5) equals $50,000. However, if, by way of further example only, Tenantagrees with its landlord to terminate Tenant’s Extension at the end of month five (5) at no cost toTenant, then Tenant’s Rent Abatement would immediately and automatically cease to accrue at the endof month five (5). If a portion but less than all of Tenant’s obligations under Tenant’s ExistingLease (as extended by Tenant’s Extension) are terminated prior to the scheduled expiration, aproportionate share of Tenant’s Rent Abatement shall cease to accrue from and after the date oftermination. By way of example only, if one-half of Tenant’s obligations shall be terminated,one-half of Tenant’s Rent Abatement shall cease to accrue and one-half shall continue to accruefrom and after the date of such termination.          (c) Any reduction in Tenant’s Rent Abatement pursuant to Subsection (b) above is in additionto any amounts credited to Landlord under Subsection (a) above. Tenant agrees to promptly providewritten notice to Landlord of any sublease/assignment and/or early termination related to Tenant’sExtension. Simultaneously with such notice, Tenant shall also provide Landlord with the estimateddollar amount of any sublease/assignment and/or early termination fee, copies of the sublease orassignment agreement, and such other documentation related to the costs and expenses of obtainingsuch sublease/assignment and/or early termination fee. In addition, upon final determination ofthe amount of the Assignment/Sublease Value, Tenant shall include a reasonably detailed statementof all income and expenses (along with copies of reasonable back-up materials) associated with theAssignment/Sublease Value and Tenant calculation thereof, along with a certification from Tenantthat all amounts and calculations set forth therein are true and correct in all material respects.          (d) Pursuant to Section 3.2(h) of the Lease, the term of the Lease shall be extended by anAbatement Extension Period if Tenant receives any Delay Abatement Credit. The portion of anyTenant’s Rent Abatement which is reduced or paid back to Landlord pursuant to this Section 7 shallnot be included in calculating the Abatement Extension Period.     8. Data Center Space. Landlord and Tenant agree that notwithstanding anything to thecontrary in the Lease or this Amendment, Landlord does not have to deliver the approximately 1,800square foot space on the 6th floor used by GSA as a data center, nor the uninterruptedpower supply station adjacent to such data center space (collectively, the “**Data Center Space**”)simultaneously with the delivery of the rest of the 6th floor, but Landlord will use allcommercially reasonable efforts to deliver the Data Center Space as soon as GSA vacates the DataCenter Space. Accordingly, the second sentence of Section 3.2(a) of the Lease is deletedand replaced with the following sentence, “As used herein, Landlord’s delivery of “substantiallyall of the Premises” shall mean that Landlord has delivered substantially all of the square footageof the Premises (other than (i) the Data Center Space and (ii) de minimus portions of the Premises,the failure to deliver which does not interfere with Tenant’s access to or beneficial occupancy ofthe Premises, Tenant’s construction schedule, Tenant’s cost to initially fit-out the Premises orcommencement of Tenant’s Work).” Notwithstanding anything to the contrary in the Lease or thisAmendment, if Landlord has delivered substantially all of the Premises other than the Data CenterSpace (the date of such delivery hereinafter being defined as the “**Initial Delivery Date**”), then,if Landlord does not deliver the Data Center Space on or before the date that is three (3) weeksafter the Initial Delivery Date, then for each day after the
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expiration of such three (3) week period until the date Landlord delivers the Data CenterSpace, the date of April 15, 2008 (or if extended by the prior sentence in this Section3.2(a) of the Lease, such later date) will be extended by an equivalent number of days.     9. Upper Floors Rent Abatement. Prior to execution of this Amendment, Landlord andTenant, along with the escrow agent, entered into an escrow agreement related to the Upper FloorsAbatement Credit (the “**Escrow Agreement**”). Landlord and Tenant agree that because Landlord hasagreed to pass certain amounts through to Tenant in accordance with Section 4 of thisAmendment, (i) Landlord shall only be required to deposit additional amounts into escrow in theevent of and in the amount of any late Additional Payments, and (ii) in the event of a terminationof the Lease in accordance with the terms thereof, Tenant shall receive only the aggregate amountof the late Additional Payments in the form of a cash payment; however, Tenant shall receive thebenefit of the Upper Floors Abatement Credit in the form of a rent abatement if the Lease is notterminated. Accordingly, concurrently with the execution and delivery of this Agreement, (i) allamounts currently held in escrow will be released and delivered to Landlord, and (ii) the EscrowAgreement is hereby amended to reflect the terms of this Section 9. In the event that Landlord hasdeposited any amounts into escrow due to late Additional Payments and Landlord later pays thecorresponding amount to Tenant, Landlord may thereafter reduce the amount deposited in escrow bythe amounts so paid to Tenant, and such reduction shall occur by the release from escrow anddelivery to Landlord of the applicable amount. In addition, all of Section 3.2(b)(4) ofthe Lease (other than the last two sentences thereof, which last two sentences remain in full forceand effect) is deleted and replaced with the following:(4) If any Additional Payment from GSA or portion thereof is late, within five (5)business days after the due date of such Additional Payment, Landlord shall pay theunpaid Additional Payment into escrow in accordance with the terms hereof, providedthat if Landlord subsequently pays Tenant the payment corresponding to anyAdditional Payment, the escrow shall be reduced by the amount of such payment toTenant, and such reduction shall occur by the release from escrow and delivery toLandlord of the applicable amount. If Tenant properly and timely terminates thisLease in accordance with the terms of Subsection 3.2(i) below, then upon theeffectiveness of Tenant’s termination, the balance of the escrowed amounts throughthe date of termination will be released from escrow and delivered to Tenant, andadditionally Landlord shall pay Tenant the portion of any Additional Paymentsaccrued prior to the effective termination date of the Lease which have not beenpaid to Tenant or placed in escrow, provided, however, that the Additional Paymentsdue on November 1, 2007 and December 1, 2007 shall be payable to Tenant only uponreceipt by Landlord from GSA. Landlord’s obligation to make such payments to Tenantshall survive termination of the Lease. Notwithstanding the foregoing, if at anytime prior to termination of the Lease Landlord delivers all Floors to Tenant, theescrowed amounts will be released from escrow and delivered to Landlord (such escrowrelease not to reduce Landlord’s obligations to use all commercially reasonableefforts to collect the Additional Payments from GSA). All interest earned on theescrowed amounts will follow such amounts and be delivered to the applicable party.The escrowed amounts will be held by an escrow agent designated by
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Tenant and reasonably acceptable to Landlord; Landlord hereby approving CommonwealthLand Title Insurance Company (c/o LandAmerica Commercial Services) as the escrowagent. Any fees charged by the escrow agent will be paid by Landlord. All sumsheld in escrow pursuant to the terms hereof will be governed by the terms of theescrow agreement attached hereto as Exhibit M, which escrow agreement will beexecuted and delivered by Landlord, Tenant and the escrow agent concurrently withthe execution and delivery of this Lease.          Section 3.2(b)(6) of the Lease is deleted and replaced with the following:(6) If, because of Landlord’s failure to timely deliver the Premises, Tenantproperly and timely terminates this Lease in accordance with the terms of the Lease,then other than (i) Landlord’s payment to Tenant of the Additional Payments as setforth in Section 4 of that certain First Amendment to Office Lease Agreement datedJune 5, 2007 (Landlord and Tenant acknowledging the contingent nature of thepayments scheduled for October 1, 2007 and November 1, 2007), (ii) Landlord’spayment (or reimbursement, as applicable) of the amounts expressly set forth inSubsection (5) and required to be paid or reimbursed in accordance with Subsection(5) immediately above, and (iii) Landlord’s return of the Security Deposit toTenant, Landlord shall not pay or be obligated to pay any additional amounts toTenant.     10. Alternative Space/Tenants. Tenant agrees that, upon full execution of thisAmendment, Tenant will immediately and until August 15, 2007 cease all efforts to lease orotherwise seek to lease or occupy other sites and spaces as an alternative to leasing the Premises.Landlord also agrees that, upon full execution of this Amendment, Landlord will immediately anduntil August 15, 2007 cease marketing the Premises as potentially available, and immediately ceaseseeking to lease the Premises to potential tenants as replacements for Tenant. Notwithstandinganything to the contrary, in addition to any other rights and remedies under the Lease, Landlordand Tenant are entitled to injunctive relief or similar remedies for a breach of the terms of thisSection 10.     11. Additional Modifications.          (a) Section 3.2(b). Add the phrase “expressly excluding the Data Center Space” in thefirst sentence after the phrase “floors 6, 7 & 8.”          (b) Section 3.2(b)(2). This section is deleted and replaced with the following:Notwithstanding the foregoing terms of this Section 3.2, (i) if Landlorddelivers any Floor to Tenant (but less than all of the Floors) and if, and only if,(a) all of the Floors (except for the Data Center Space) are delivered within three(3) weeks of the first delivery of a Floor to Tenant and (b) the Data Center Spaceis delivered within three (3) weeks of the delivery of the balance of the Floors(except for the Data Center Space), the Upper Floors Abatement Credit will bereduced on a pro rata basis (based on the rentable square footage of the Floors) forthe applicable Floor(s) delivered from the date of delivery, and (ii) upon delivery
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of the Floors (or the last Floor, in the event delivery of the Floors is staggeredon a floor by floor basis), the Upper Floors Abatement Credit will be prorated basedon the number of days in the applicable calendar month of delivery. By way ofexample only of the foregoing terms of Subsection (b), if Landlord delivers theFloors to Tenant in the Ready Condition on June 10, 2007, the Upper Floors AbatementCredit will equal the sum of One Hundred Fifty Thousand Dollars ($150,000) (whichsum is made up of $100,000 for the calendar month of May and $5,000 per day for theten (10) days in the calendar month of June; i.e., for the calendar month of Junethe total scheduled abatement of $150,000 divided by 30 days is $5,000 per day).          (c) Section 3.2(b)(3). This section is deleted and replaced with the following:Any such phased delivery of a Floor and resultant pro rata abatement reduction shallnot modify the Lease Commencement Date. Landlord shall not deliver, and Tenantshall not be obligated to accept, any partial floors that comprise the Floors,except for the sixth (6th) floor, which Landlord may deliver and Tenantshall accept without the Data Center Space. Tenant shall, however, accept an entirefloor so long as such floor is delivered in Ready Condition (except for the sixth(6th) floor, which may be delivered without the Data Center Space asprovided above).          (d) Section 3.2(d). Romanette (i) of the first sentence of this section is deletedand replaced with the following:(i) the term of its lease for the 1899 L Space (“**Tenant’s Existing Lease**”) has beenextended to April 30, 2008 (subject to a one-time right to extend the term thereofup to and until December 31, 2008, which as of June 1, 2007, must be exercised (ifat all) on or before June 15, 2007), and that Tenant leases approximately 72,727rentable square feet under Tenant’s Existing Lease andAlso, Landlord and Tenant agree that the Swing/Extension Abatement will not be applicable to morethan six (6) months of extended term or swing space (i.e., three (3) months of abatement by virtueof the one-for-two applicability of such abatement). Accordingly, the phrase “more than eight (8)months of extended term or swing space (i.e., four (4) months of abatement” in the fourth(4th) sentence of Section 3.2(d) is deleted and replaced with the phrase “morethan six (6) months of extended term or swing space (i.e., three (3) months of abatement”.          (e) Section 3.2(i). The last sentence of this section is deleted and replaced withthe following:Notwithstanding the provisions of Article XXX of this Lease to the contrary, no termination feeshall be payable by Tenant in the event Tenant terminates the Lease pursuant to the provisions ofthis Section 3.2.
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     12. Ratification. Except as expressly modified by the terms of this Amendment, theLease shall remain unchanged and continue in full force and effect. All terms, covenants andconditions of the Lease applicable to the Premises, as amended hereby, are confirmed and ratified,remain in full force and effect, and constitute valid and binding obligations of Landlord andTenant, enforceable according to the terms thereof.     13. Authority. Landlord, Tenant and the persons executing and delivering thisAmendment on their respective behalves each represents and warrants that such person is dulyauthorized to so act, and has the power and authority to enter into this Amendment, and that allaction required to authorize Landlord, Tenant and such person to enter into this Amendment has beenduly taken.     14. Binding Effect. This Amendment shall not be effective and binding unless anduntil fully executed and delivered by each of the parties hereto. All of the covenants containedin this Amendment, including, but not limited to, all covenants of the Lease as modified hereby,shall be binding upon and inure to the benefit of the parties hereto, their respective heirs, legalrepresentatives, and permitted successors and assigns. In the event of a conflict between theterms of the Lease and the terms of this Amendment, the terms of this Amendment will control. ThisAmendment will be effective between Landlord and Tenant when executed and delivered by such partiesregardless of whether escrow agent executes and delivers this Amendment.     15. Condition. Notwithstanding anything to the contrary, the effectiveness of thisAmendment is expressly conditioned upon simultaneous execution and delivery of the New SLA byLandlord and GSA.     16. Counterparts. This Amendment may be executed in multiple counterparts, each ofwhich shall constitute an original, and all of which, together, shall constitute one and the samedocument.     17. Letter of Accounting. Within thirty (30) days following the delivery date of thePremises, the parties shall use their good faith efforts to execute a letter of accounting whichsets forth a calculation of the abatement credits due to Tenant in respect of the Lease. Withinthirty (30) days following the Lease Commencement Date, the parties shall use their good faithefforts to amend the letter of accounting to reflect any further adjustments or specifications toinformation contained therein. The failure to execute such letter of accounting or any amendmentthereto shall not affect the parties’ rights or obligations under the Lease. Each party shall payits own expenses in reviewing and executing such letter.*[signatures on next page]*
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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly executed as of thedate first above written.         WITNESS/ATTEST: LANDLORD:               WASHINGTON TELEVISION CENTER LLC, a District of    Columbia limited liability company             By: WTC Realty, Inc., a Delaware corporation,