LEASE AGREEMENT

Exhibit 10.15

LEASE AGREEMENT

        THIS LEASE AGREEMENT is made as of this 7th day of November, 2006, between ARE-79/96 CHARLESTOWN NAVY YARD, LLC, a Delaware limited liability company (" Landlord "), and MYTOGEN, INC., a Delaware corporation (" Tenant ").

BASIC LEASE PROVISIONS

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        1.     Lease of Premises.     Upon and subject to all of the terms and conditions hereof, Landlord hereby leases the Premises to Tenant and Tenant hereby leases the Premises from Landlord. To the extent necessary for the Tenant's use of the Premises for the Permitted Use, and to the extent that Landlord has the benefit thereof, Tenant shall have the benefit of the easements contained in Section 31.24 of the Ground Lease (as defined in Section 2) and other easements and appurtenant rights of record; provided, however, that the foregoing shall not give the Tenant any right to perform any work or alterations on or in any areas outside of the Premises, including without limitation any below-grade footings, and in the exercise of such rights or otherwise Tenant shall not take any action that would constitute a breach of or default under the Ground Lease. Landlord reserves the right to modify the portions of the Project outside of the Premises, provided that such modifications do not materially adversely affect Tenant's use of the Premises for the Permitted Use. Notwithstanding anything to the contrary, this Lease shall be subject to, and the effectiveness of this Lease and the transaction evidenced hereby shall be conditioned upon, the consent of LaSalle (as defined in Section 27), the holder of the Leasehold Mortgage and Security Agreement on the Project as of the date hereof as described in Section 27. Upon execution of this Lease by Tenant, Landlord shall promptly seek such consent from such Holder. Upon receipt of such consent, Landlord shall provide a copy thereof to Tenant.

        2.     Delivery; Acceptance of Premises; Commencement Date.     Landlord shall use reasonable efforts to make the Premises available to Tenant for Tenant's Work under the Tenant Improvement Work Letter attached as Exhibit C (the " TI Work Letter ") within 5 days of full execution of this Lease and Tenant's delivery of evidence of the insurance required by Section 17 and by the TI Work Letter (" Delivery " or " Deliver "). Landlord and Tenant acknowledge that Tenant currently occupies a portion of the Premises as a subtenant under that certain Sublease dated December 28, 2005 between Genvec, Inc. as Sublandlord and Tenant as Subtenant (the " Sublease ") under that certain Sublease dated June 24, 1991 between Landlord and Diacrin, Inc., as amended by a First Amendment to Sublease dated April 30, 2002 and effective as of October 4, 2001 (as amended, the " Overlease "), which Sublease and Overlease terminate as of 11:59 p.m. on October 3, 2006. Tenant acknowledges that it currently has and will retain exclusive possession of the premises subleased under the Sublease (the " Subleased Premises ") and no property or personnel of any third party are located in such Subleased Premises. If Landlord fails to timely Deliver the Premises, Landlord shall not be liable to Tenant for any loss or damage resulting therefrom, and this Lease shall not be void or voidable except as provided herein. With respect to any part of the Premises that is outside of the Subleased Premises (the " Non-subleased Premises "), if Landlord fails to Deliver the Non-subleased Premises on or before the Target Commencement Date, Tenant's sole and exclusive remedy for such failure shall be that the portion of Rent attributable to the Non-subleased Premises (based on square footage) shall be abated on a day-for-day basis for each day between the Target Commencement Date and the date that Landlord Delivers the Non-subleased Premises.

        To the extent that the provisions thereof are applicable an Occupancy Tenant (as that term is defined in the Ground Lease) or to any lease or sublease with an Occupancy Tenant, this Lease is also subject and subordinate to the terms and conditions of the following ground leases, which are collectively referred to herein as the " Ground Lease ", as the same may be amended and/or renewed: (i) the Ground Lease for Building 79 dated September 23, 1988 by and between the Boston Redevelopment Authority (the " BRA "), as landlord, and Boston Harbor Investment Group, Inc., as tenant, notice of which is recorded with the Suffolk County Registry of Deeds in Book 15967, Page 008, and (ii) the Ground Lease for Building 96 dated May 18, 1990 by and between the BRA, as landlord, and Building 96 Associates Limited partnership, as tenant, notice of which is recorded with said Registry of Deeds in Book 16408, Page 17. In the event that the BRA shall at any time during the Term disapprove of Tenant's use of the Premises for the Permitted Use, Tenant shall not on account of use of the Premises for the Permitted Use be in default hereunder (it being understood that the foregoing shall not affect Landlord's rights hereunder with respect to any use that is not a Permitted

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Use). Landlord has made, or no later than 5 days after any receipt by Landlord of an subordination, nondisturbance and attornment agreement executed by LaSalle (as defined in Section 27) will make, a written request to the BRA to execute and deliver to Tenant a subordination, non-disturbance and attornment agreement in favor of Tenant with respect to the Ground Lease, and during the 60-day period following the later of (i) the date of such written request, or (ii) the date of this Lease, Landlord will follow-up on such request in a manner that is in Landlord's judgment commercially reasonable. In no event shall the foregoing require Landlord to pay any consideration in connection with such request or as may otherwise be requested by the BRA, submit any claim, make demand or commence litigation or any other proceeding in connection with the Ground Lease or such request. If the BRA fails or refuses to execute such subordination, non-disturbance and attornment agreement, or requests consideration related thereto which Landlord does not elect to pay, Landlord shall not be in breach of its obligations under this Lease. In the event that within such 60-day period, the BRA has not executed and delivered the requested subordination, non-disturbance and attornment agreement, Tenant may terminate this Lease, which termination may be exercised, if at all, by notice to Landlord within 10 days of the end of such 60-day period. The date set forth in such notice for such termination shall be no later than 60 days after the date of such notice, and in such event, the surrender and yield up by Tenant shall be pursuant to and in accordance with this Lease.

        If Landlord does not Deliver the Premises within 30 days of the Target Commencement Date for any reason other than Force Majeure Delays, this Lease may be terminated by Landlord or Tenant by written notice to the other, and if so terminated by either: (a) the Security Deposit, or any balance thereof (i.e., after deducting therefrom all amounts to which Landlord is entitled under the provisions of this Lease), shall be returned to Tenant, and (b) neither Landlord nor Tenant shall have any further rights, duties or obligations under this Lease, except with respect to provisions which expressly survive termination of this Lease. As used herein, the terms " Tenants' Work ," and " Substantially Complete " shall have the meanings set forth for such terms in the TI Work Letter. If neither Landlord nor Tenant elects to void this Lease within 5 business days of the lapse of such 30 day period, such right to void this Lease shall be waived and this Lease shall remain in full force and effect.

        The " Term " of this Lease shall be the Base Term, as defined above in the Basic Lease Provisions and any Extension Terms which Tenant may elect pursuant to Section 39 .

        Except as set forth in the TI Work Letter, if applicable, and except as expressly provided below in this Section 2: (i) Tenant shall accept the Premises in their condition as of the date on which Landlord Delivers the Premises as set forth above, subject to all applicable Legal Requirements (as defined in Section 7 hereof); (ii) Landlord shall have no obligation for any defects in the Premises; and (iii) Tenant's taking possession of the Premises shall be conclusive evidence that Tenant accepts the Premises and that the Premises were in good condition at the time possession was taken. Any occupancy of any portion of the Premises, which portion was not included prior to the Commencement Date in the premises subleased to Tenant under the Sublease, shall be subject to all of the terms and conditions of this Lease. Tenant shall be responsible for ensuring that Tenant's Work is performed in compliance with all applicable Legal Requirements.

        Landlord agrees to replace at its expense, subject to the cost caps set forth below: (1) the air handling system in the Building, including the main chiller, the air-conditioning and heating system, fans and duct work connected to such system (the " Air Handling System ") pursuant to the Air Handling System Work Letter attached hereto as Exhibit F (the " AHS Work Letter "), and (2) the Building's emergency power generator (the " Generator "). The specification for the Air Handling System, shall be determined pursuant to the process set forth in the AHS Work Letter, and the specification for the Generator shall be mutually acceptable to Tenant and Landlord; provided, however, that the aggregate cost to purchase and install the Generator and perform all work related thereto shall not exceed $150,000 (the " Generator Cost Cap ") and the aggregate cost to purchase the equipment and materials necessary for the Air Handling System and perform Landlord's AHS Work

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(as defined in the AHS Work Letter) shall not exceed $350,000 (the " AHS Cost Cap "). In the event that, following the purchase of the Generator, full and final completion of the work related to the installation of the Generator and payment of all hard and soft costs in connection therewith, such expenditures are less than the Generator Cost Cap, the difference between such expenditures and the Generator Cost Cap shall be added to the AHS Cost Cap. Subject to the AHS Cost Cap, Landlord shall Substantially Complete the installation of such Air Handling System within the time period set forth in the AHS Work Letter, subject to Force Majeure and any delays caused by Tenant as provided in the AHS Work Letter. Landlord shall Substantially Complete the installation of the Generator within 6 months of the Commencement Date, subject to Force Majeure (as defined in Section 34) and any delays caused by Tenant.

        In addition, prior to the Commencement Date, subject to Force Majeure and any delays caused by Tenant, Landlord shall at its expense repair existing leaks and penetrations in the Building enclosure. The time periods for the foregoing work on the Air Handling System, Generator and repair of leaks and penetrations may be reasonably extended by Landlord provided that Landlord continues diligently to pursue completion thereof.

        Tenant agrees and acknowledges that neither Landlord nor any agent of Landlord has made any representation or warranty with respect to the condition of all or any portion of the Premises or the Project, and/or the suitability of the Premises or the Project for the conduct of Tenant's business, and Tenant waives any implied warranty that the Premises or the Project are suitable for the Permitted Use. This Lease constitutes the complete agreement of Landlord and Tenant with respect to the subject matter hereof and supersedes any and all prior representations, inducements, promises, agreements, understandings and negotiations which are not contained herein. Landlord in executing this Lease does so in reliance upon Tenant's representations, warranties, acknowledgments and agreements contained herein.

        3.     Rent .    

•         (a)     Base Rent.     The first month's Base Rent and the Security Deposit shall be due and payable on delivery of an executed copy of this Lease to Landlord. Tenant shall pay to Landlord in advance, without demand, abatement, deduction or set-off, monthly installments of Base Rent on or before the first day of each calendar month during the Term hereof in lawful money of the United States of America, at the office of Landlord for payment of Rent set forth above, or to such other person or at such other place as Landlord may from time to time designate in writing. Payments of Base Rent for any fractional calendar month shall be prorated. The obligation of Tenant to pay Base Rent and other sums to Landlord and the obligations of Landlord under this Lease are independent obligations. Tenant shall have no right at any time to abate, reduce, or set-off any Rent (as defined in Section 5 ) due hereunder except for any abatement as may be expressly provided in this Lease.

          (b)     Additional Rent.     In addition to Base Rent, Tenant agrees to pay to Landlord as additional rent (" Additional Rent "): (i) Tenant's Share of "Operating Expenses" (as defined in Section 5 ), and (ii) any and all other amounts Tenant assumes or agrees to pay under the provisions of this Lease, including, without limitation, any and all other sums that may become due by reason of any default of Tenant or failure to comply with the agreements, terms, covenants and conditions of this Lease to be performed by Tenant, after any applicable notice and cure period.

        4.     Base Rent Adjustments.     Base Rent shall be increased on each annual anniversary of the first day of the first full month of the Term of this Lease beginning with the second such annual anniversary (each an " Adjustment Date ") by multiplying the Base Rent payable immediately before such Adjustment Date by the Rent Adjustment Percentage and adding the resulting amount to the Base Rent payable immediately before such Adjustment Date. Base Rent, as so adjusted, shall thereafter be due as provided herein. Base Rent adjustments for any fractional calendar month shall be prorated. If

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this Lease is extended pursuant to Section 39, Base Rent for the first year of the Extension Term (as that term is defined in Section 39) shall be as determined under Section 39(a) and shall thereafter be adjusted on each annual anniversary of the commencement of such Extension Term.

        5.     Operating Expense Payments.     Landlord shall deliver to Tenant a written estimate of Operating Expenses for each calendar year during the Term (the " Annual Estimate "), which may be revised by Landlord from time to time during such calendar year. During each month of the Term, on the same date that Base Rent is due, Tenant shall pay Landlord an amount equal to ¹ / 12 th of Tenant's Share of the Annual Estimate. Payments for any fractional calendar month shall be prorated.

        The term " Operating Expenses " means all costs and expenses of any kind or description whatsoever incurred or accrued each calendar year by Landlord with respect to the Project (including, without duplication, Taxes (as defined in Section 9 ), capital repairs and improvements made by Landlord in order to (i) reduce Operating Expenses, (ii) comply with changes in Legal Requirements, or (iii) repair or replace failing or failed HVAC equipment serving the Project, in each case amortized over the useful life of such capital items, and the costs of Landlord's third party property manager or, if there is no third party property manager, administration rent in the amount of 2.0% of Base Rent), excluding only:

•         (a)   the original construction costs of the Project and renovation prior to the date of the Lease and costs of correcting defects in such original construction or renovation;

          (b)   capital expenditures for expansion of the Project or for purposes other than those expressly set forth in this Lease;

          (c)   interest, principal payments of Mortgage (as defined in Section 27 ) debts of Landlord, financing costs and amortization of funds borrowed by Landlord, whether secured or unsecured and all payments of base rent (but not taxes or operating expenses) under any ground lease or other underlying lease of all or any portion of the Project;

          (d)   depreciation of the Project (except for capital improvements, the cost of which are includable in Operating Expenses as set forth above);

          (e)   advertising, legal and space planning expenses and leasing commissions and other costs and expenses incurred in procuring and leasing space to tenants for the Project, if any, including any leasing office maintained in the Project, free rent and construction allowances for tenants;

          (f)    legal and other expenses incurred in the negotiation or enforcement of leases;

          (g)   completing, fixturing, improving, renovating, painting, redecorating or other work, which Landlord pays for or performs for other tenants within their premises, and costs of correcting defects in such work;

          (h)   costs to be reimbursed by other tenants of the Project, if any, or Taxes to be paid directly by Tenant or other tenants of the Project, if any, whether or not actually paid;

          (i)    salaries, wages, benefits and other compensation paid to officers and employees of Landlord who are not assigned in whole or in part to the operation, management, maintenance or repair of the Project (but if assigned only in part to the Project, then only the prorated portion of such salary, wages, benefits and other compensation shall be chargeable as an Operating Expense);

          (j)    general organizational, administrative and overhead costs relating to maintaining Landlord's existence, either as a corporation, partnership, or other entity, including general corporate, legal and accounting expenses;

          (k)   costs (including attorneys' fees and costs of settlement, judgments and payments in lieu thereof) incurred in connection with disputes with tenants, other occupants, or prospective tenants,

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  and costs and expenses, including legal fees, incurred in connection with negotiations or disputes with employees, consultants, management agents, leasing agents, purchasers or mortgagees of the Building;

          (l)    costs incurred by Landlord due to the violation by Landlord, its employees, agents or contractors or any tenant of the terms and conditions of any lease of space in the Project or any Legal Requirement (as defined in Section 7 );

          (m)  penalties, fines or interest incurred as a result of Landlord's inability or failure to make payment of Taxes and/or to file any tax or informational returns when due, or from Landlord«'s failure to make any payment of Taxes required to be made by Landlord hereunder before delinquency;

          (n)   overhead and profit increment paid to Landlord or to subsidiaries or affiliates of Landlord for goods and/or services in or to the Project to the extent the same exceeds the costs of such goods and/or services rendered by unaffiliated third parties on a competitive basis;

          (o)   costs of Landlord's charitable or political contributions, or of fine art maintained at the Project;

          (p)   costs in connection with services (including electricity), items or other benefits of a type which are not standard for the Project and which are not available to Tenant without specific charges therefor, but which are provided to another tenant or occupant of the Project, whether or not such other tenant or occupant is specifically charged therefor by Landlord;

          (q)   costs incurred in the sale or refinancing of the Project;

          (r)   net income taxes of Landlord or the owner of any interest in the Project, franchise, capital stock, gift, estate or inheritance taxes or any federal, state or local documentary taxes imposed against the Project or any portion thereof or interest therein; and

          (s)   any expenses otherwise includable within Operating Expenses to the extent actually reimbursed by persons other than tenants of the Project under leases for space in the Project.

        Within 90 days after the end of each calendar year (or such longer period as may be reasonably required), Landlord shall furnish to Tenant a statement (an " Annual Statement ") showing in reasonable detail: (a) the total and Tenant's Share of actual Operating Expenses for the previous calendar year, and (b) the total of Tenant's payments in respect of Operating Expenses for such year. If Tenant's Share of actual Operating Expenses for such year exceeds Tenant's payments of Operating Expenses for such year, the excess shall be due and payable by Tenant as Rent within 30 days after delivery of such Annual Statement to Tenant. If Tenant's payments of Operating Expenses for such year exceed Tenant's Share of actual Operating Expenses for such year Landlord shall pay the excess to Tenant within 30 days after delivery of such Annual Statement, except that after the expiration, or earlier termination of the Term or if Tenant is delinquent in its obligation to pay Rent, Landlord shall pay the excess to Tenant after deducting all other amounts due Landlord, if any.

        The Annual Statement shall be final and binding upon Tenant unless Tenant, within 30 days after Tenant's receipt thereof, shall contest any item therein by giving written notice to Landlord, specifying each item contested and the reason therefor. If, during such 30 day period, Tenant in good faith questions or contests the accuracy of Landlord's statement of Tenant's Share of Operating Expenses, Landlord will provide Tenant with access to Landlord's books and records relating to the operation of the Project and such information as Landlord reasonably determines to be responsive to Tenant's questions (the " Expense Information "). If after Tenant's review of such Expense Information, Landlord and Tenant cannot agree upon the amount of Tenant's Share of Operating Expenses, then Tenant shall have the right to have an independent public accounting firm selected by Tenant from among the 5 largest in the United States or the reputable independent public accounting firms in the New England

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region, working pursuant to a fee arrangement other than a contingent fee (at Tenant's sole cost and expense) and approved by Landlord (which approval shall not be unreasonably withheld or delayed), audit and/or review the Expense Information for the year in question (the " Independent Review "). The results of any such Independent Review shall be binding on Landlord and Tenant. If the Independent Review shows that the payments actually made by Tenant with respect to Operating Expenses for the calendar year in question exceeded Tenant's Share of Operating Expenses for such calendar year, Landlord shall at Landlord's option either (i) credit the excess amount to the next succeeding installments of estimated Operating Expenses or (ii) pay the excess to Tenant within 30 days after delivery of such statement, except that after the expiration or earlier termination of this Lease or if Tenant is delinquent in its obligation to pay Rent, Landlord shall pay the excess to Tenant after deducting all other amounts due Landlord. If the Independent Review shows that Tenant's payments with respect to Operating Expenses for such calendar year were less than Tenant's Share of Operating Expenses for the calendar year, Tenant shall pay the deficiency to Landlord within 30 days after delivery of such statement. If the Independent Review shows that Tenant has overpaid with respect to Operating Expenses by more than 5% then Landlord shall reimburse Tenant for all costs incurred by Tenant for the Independent Review. Operating Expenses for the calendar years in which Tenant's obligation to share therein begins and ends shall be prorated.

        " Tenant's Share " shall be the percentage set forth in the Basic Lease Provisions as Tenant's Share as reasonably adjusted by Landlord for changes in the physical size of the Premises or the Project occurring thereafter. Any such measurement shall be performed in accordance with the 1996 Standard Method of Measuring Floor Area in Office Buildings as adopted by the Building Owners and Managers Association (ANSI/BOMA Z65.1-1996). Landlord may equitably increase Tenant's Share for any item of expense or cost reimbursable by Tenant that relates to a repair, replacement, or service that benefits only the Premises or only a portion of the Project that includes the Premises or that varies with occupancy or use. Base Rent, Tenant's Share of Operating Expenses and all other amounts payable by Tenant to Landlord hereunder are collectively referred to herein as " Rent ."

        6.     Security Deposit.     Tenant shall deposit with Landlord, upon delivery of an executed copy of this Lease to Landlord, a security deposit (the " Security Deposit ") for the performance of all of Tenant's obligations hereunder in the amount set forth in the Basic Lease Provisions, which Security Deposit shall be in the form of an unconditional and irrevocable letter of credit (the " Letter of Credit "): (i) in form and substance reasonably satisfactory to Landlord, (ii) naming Landlord as beneficiary, (iii) expressly allowing Landlord to draw upon it at any time from time to time by delivering to the issuer notice that Landlord is entitled to draw thereunder, (iv) issued by an FDIC-insured financial institution reasonably satisfactory to Landlord, and (v) redeemable by presentation of a sight draft in the state of Landlord's choice. If Tenant does not provide Landlord with a substitute Letter of Credit complying with all of the requirements hereof at least 10 days before the stated expiration date of any then current Letter of Credit, Landlord shall have the right to draw the full amount of the current Letter of Credit and hold the funds drawn in cash without obligation for interest thereon as the Security Deposit. The Security Deposit shall be held by Landlord as security for the performance of Tenant's obligations under this Lease. The Security Deposit is not an advance rental deposit or a measure of Landlord's damages in case of Tenant's default. Upon each occurrence of a Default (as defined in Section 20 ), Landlord may use all or any part of the Security Deposit to pay delinquent payments due under this Lease, and the cost of any damage, injury, expense or liability caused by such Default, without prejudice to any other remedy provided herein or provided by law. Upon any such use of all or any portion of the Security Deposit, Tenant shall pay Landlord on demand the amount that will restore the Security Deposit to the amount set forth in the Basic Lease Provisions. Tenant hereby waives the provisions of any law, now or hereafter in force, which provide that Landlord may claim from a security deposit only those sums reasonably necessary to remedy defaults in the payment of Rent, to repair damage caused by Tenant or to clean the Premises, it being agreed that Landlord may, in addition, claim those sums reasonably necessary to compensate Landlord for any

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other loss or damage, foreseeable or unforeseeable, caused by the act or omission of Tenant or any officer, employee, agent or invitee of Tenant, which act or omission constitutes a breach by Tenant of its obligations under this Lease. Upon bankruptcy or other debtor-creditor proceedings against Tenant, the Security Deposit shall be deemed to be applied first to the payment of Rent and other charges due Landlord for periods prior to the filing of such proceedings. Upon any such use of all or any portion of the Security Deposit, Tenant shall, within 10 days after demand from Landlord, restore the Security Deposit to its original amount. If Tenant shall fully perform every provision of this Lease to be performed by Tenant, the Security Deposit, or any balance thereof (i.e., after deducting therefrom all amounts to which Landlord is entitled under the provisions of this Lease), shall be returned to Tenant (or, at Landlord's option, to the last assignee of Tenant's interest hereunder provided Tenant has assigned its interest in the Security Deposit to such assignee) within 60 days after the expiration or earlier termination of this Lease.

        If Landlord transfers its interest in the Project or this Lease, Landlord shall either (a) transfer any Security Deposit then held by Landlord to a person or entity assuming Landlord's obligations under this Section 6 , or (b) return to Tenant any Security Deposit then held by Landlord and remaining after the deductions permitted herein. Upon such transfer to such transferee or the return of the Security Deposit to Tenant, Landlord shall have no further obligation with respect to the Security Deposit, and Tenant's right to the return of the Security Deposit shall apply solely against Landlord's transferee. The Security Deposit is not an advance rental deposit or a measure of Landlord's damages in case of Tenant's default. Landlord's obligation respecting the Security Deposit is that of a debtor, not a trustee, and no interest shall accrue thereon.

        7.     Use.     The Premises shall be used solely for the Permitted Use set forth in the Basic Lease Provisions, and in compliance with all laws, orders, judgments, ordinances, regulations, codes, directives, permits, licenses, covenants and restrictions now or hereafter applicable to the Premises, and to the use and occupancy thereof, including, without limitation, the Americans With Disabilities Act, 42 U.S.C. § 12101, et seq. (together with the regulations promulgated pursuant thereto, " ADA ") (collectively, " Legal Requirements " and each, a " Legal Requirement "). Tenant shall, upon 5 days' written notice from Landlord, discontinue any use of the Premises which is declared by any Governmental Authority (as defined in Section 9 ) having jurisdiction to be a violation of a Legal Requirement. Tenant will not use or permit the Premises to be used for any purpose or in any manner that would void Tenant's or Landlord's insurance, increase the insurance risk, or cause the disallowance of any sprinkler or other credits. Tenant shall not permit any part of the Premises to be used as a "place of public accommodation", as defined in the ADA or any similar legal requirement. Tenant shall reimburse Landlord promptly upon demand for any additional premium charged for any such insurance policy by reason of Tenant's failure to comply with the provisions of this Section or otherwise caused by Tenant's use and/or occupancy of the Premises. Tenant will use the Premises in a careful and safe manner and will not commit or permit waste, overload the floor or structure of the Premises, subject the Premises to use that would damage the Premises or obstruct or interfere with the rights of Landlord or other tenants or occupants of the Project, if any, including conducting or giving notice of any auction, liquidation, or going out of business sale on the Premises, or using or allowing the Premises to be used for any unlawful purpose. Tenant shall cause any equipment or machinery to be installed in the Premises so as to reasonably prevent sounds or vibrations from the Premises from extending into areas outside of the Premises or other space in the Project. Tenant shall not place any machinery or equipment weighing 500 pounds or more in or upon the Premises or transport or move such items through the Project or in the Project elevators without the prior written consent of Landlord. Except as may be provided under the TI Work Letter, Tenant shall not, without the prior written consent of Landlord, use the Premises in any manner which will require ventilation, air exchange, heating, gas, steam, electricity or water beyond the existing capacity of the Project as proportionately allocated to the Premises based upon Tenant's Share as usually furnished for the Permitted Use.

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        Landlord has received no written notice from any Governmental Authority (as defined in Section 9 below) that Premises are not in compliance with applicable Legal Requirements or the applicable provisions of the ADA.

        Landlord shall, as an Operating Expense (to the extent such Legal Requirement is generally applicable to the Building irrespective of Tenant's particular use of the Premises or any alteration made by Tenant) or at Tenant's expenses (to the extent such Legal Requirement is applicable solely by reason of Tenant's particular use of the Premises or any alteration made by Tenant) make any alterations or modifications to the exterior of the Building that are required by Legal Requirements, including the ADA. Tenant, at its sole expense, shall make any alterations or modifications to the interior of the Premises that are required by Legal Requirements during the Term (including, without limitation, compliance of the Premises with the ADA). Notwithstanding any other provision herein to the contrary, Tenant shall be responsible for any and all demands, claims, liabilities, losses, costs, expenses, actions, causes of action, damages or judgments, and all reasonable expenses incurred in investigating or resisting the same (including, without limitation, reasonable attorneys' fees, charges and disbursements and costs of suit) (collectively, " Claims ") arising out of or in connection with Tenant's failure to comply with Legal Requirements, and Tenant shall indemnify, defend, hold and save Landlord harmless from and against any and all Claims arising out of or in connection with any failure of the Premises to comply with any Legal Requirement.

        8.     Holding Over.     If, with Landlord's express written consent, Tenant retains possession of the Premises after the termination of the Term, (i) unless otherwise agreed in such written consent, such possession shall be subject to immediate termination by Landlord at any time, (ii) all of the other terms and provisions of this Lease (including, without limitation, the adjustment of Base Rent pursuant to Section 4 hereof) shall remain in full force and effect (excluding any expansion or renewal option or other similar right or option) during such holdover period, (iii) Tenant shall continue to pay Base Rent in the amount payable upon the date of the expiration or earlier termination of this Lease or such other amount as Landlord may indicate, in Landlord's sole and absolute discretion, in such written consent, and (iv) all other payments shall continue under the terms of this Lease. If Tenant remains in possession of the Premises after the expiration or earlier termination of the Term without the express written consent of Landlord, (A) Tenant shall become a tenant at sufferance upon the terms of this Lease except that the monthly rental shall be equal to 150% of Rent in effect during the last 30 days of the Term, and (B) Tenant shall be responsible for all damages suffered by Landlord resulting from or occasioned by Tenant's holding over, including consequential damages. No holding over by Tenant, whether with or without consent of Landlord, shall operate to extend this Lease except as otherwise expressly provided, and this Section 8 shall not be construed as consent for Tenant to retain possession of the Premises. Acceptance by Landlord of Rent after the expiration of the Term or earlier termination of this Lease shall not result in a renewal or reinstatement of this Lease.

        9.     Taxes.     Landlord shall pay, as part of Operating Expenses, all taxes, levies, assessments and governmental charges of any kind (collectively referred to as " Taxes ") imposed by any federal, state, regional, municipal, local or other governmental authority or agency, including, without limitation, quasi-public agencies (collectively, " Governmental Authority ") during the Term, including, without limitation, all Taxes: (i) imposed on or measured by or based, in whole or in part, on rent payable to Landlord under this Lease and/or from the rental by Landlord of the Project or any portion thereof, or (ii) based on the square footage, assessed value or other measure or evaluation of any kind of the Premises or the Project, or (iii) assessed or imposed by or on the operation or maintenance of any portion of the Premises or the Project, including parking, or (iv) assessed or imposed by, or at the direction of, or resulting from statutes or regulations, or interpretations thereof, promulgated by, any Governmental Authority, or (v) imposed as a license or other fee on Landlord's business of leasing space in the Project. Landlord may contest by appropriate legal proceedings the amount, validity, or application of any Taxes or liens securing Taxes. Notwithstanding the foregoing, provided that Tenant is

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not in default under this Lease, in the event that (a) the Premises are re-assessed during the Term whereby Taxes for a municipal fiscal year increase more than 15% over the Taxes for the immediately preceding municipal fiscal year, and (b) Tenant owes any additional amounts on account of Taxes for a prior time period (whether such period is during the Term of this Lease or during the term of the Sublease), Tenant may pay Landlord as Additional Rent such additional amounts in 6 equal monthly installments commencing with the first day of the first month immediately after the date that Tenant is notified of such re-assessment. The foregoing shall not reduce or abrogate the obligation of Tenant to pay such Taxes to Landlord as Additional Rent hereunder. Taxes shall not include any net income taxes imposed on Landlord unless such net income taxes are in substitution for any Taxes payable hereunder. If any such Tax is levied or assessed directly against Tenant, then Tenant shall be responsible for and shall pay the same at such times and in such manner as the taxing authority shall require. Tenant shall pay, prior to delinquency, any and all Taxes levied or assessed against any personal property or trade fixtures placed by Tenant in the Premises, whether levied or assessed against Landlord or Tenant. If any Taxes on Tenant's personal property or trade fixtures are levied against Landlord or Landlord's property, or if the assessed valuation of the Project is increased by a value attributable to improvements in or alterations to the Premises, whether owned by Landlord or Tenant and whether or not affixed to the real property so as to become a part thereof, Landlord shall have the right, but not the obligation, to pay such Taxes. Landlord's determination of any excess assessed valuation shall be binding and conclusive, absent manifest error. The amount of any such payment by Landlord shall constitute Additional Rent due from Tenant to Landlord immediately upon demand.

        10.     Parking.     Subject to the Ground Lease, all matters of record as of the date hereof, Force Majeure, a Taking (as defined in Section 19 below) and the exercise by Landlord of its rights hereunder, Tenant shall have such rights as a tenant of the Project may be entitled to under the Ground Lease, if any, in common with others entitled thereto, to park in those areas referenced in the Ground Lease and designated for non-reserved parking, subject in each case to any rules and regulations as may be applicable thereto. Landlord shall not release or terminate such parking rights as are granted in the Ground Lease but Landlord shall not be responsible for enforcing Tenant's parking rights against any third parties. Tenant acknowledges and agrees that if Tenant desires to obtain any parking rights or licenses with respect to the garage at Building 199 in the Charlestown Navy Yard, Tenant may contact such garage directly and procure same at Tenant's sole cost and expense. Landlord shall have no responsibility with respect thereto nor shall Landlord's rights or Tenant's obligations under this Lease be affected thereby.

        11.     Utilities, Services.     Tenant shall contract directly with third-party utility and service providers for all utilities serving the Premises, including water, electricity, heat, light, power, telephone, sewer, and other utilities (including gas and fire sprinklers to the extent the Project is plumbed for such services), and Tenant shall contract for refuse and trash collection and janitorial services (collectively, " Utilities "). Tenant shall pay prior to delinquency directly to such utility and service providers all of the costs for all Utilities used on the Premises, all maintenance charges for Utilities, and any storm sewer charges or other similar charges for Utilities imposed by any Governmental Authority or Utility provider, and any taxes, penalties, surcharges or similar charges thereon. No interruption or failure of Utilities, from any cause whatsoever other than Landlord's willful misconduct, shall result in eviction or constructive eviction of Tenant, termination of this Lease or the abatement of Rent.

        Following the completion of the installation of the Generator as provided in Section 2, Landlord's sole obligation for either providing emergency generators or providing emergency back-up power to Tenant shall be: (i) to provide an emergency generator with not less than the stated capacity of the Generator installed pursuant to Section 2, and (ii) to contract with a third party to maintain the Generator as per the manufacturer's standard maintenance guidelines. Landlord shall have no obligation to provide Tenant with operational emergency generator or back-up power or to supervise, oversee or confirm that the third party maintaining the Generator is maintaining the Generator as per

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the manufacturer's standard guidelines or otherwise. During any period of replacement, repair or maintenance of the Generator when the Generator is not operational, including any delays thereto due to the inability to obtain parts or replacement equipment, Landlord shall have no obligation to provide Tenant with an alternative back-up generator or generators or alternative sources of back-up power. Tenant expressly acknowledges and agrees that Landlord does not guaranty that such Generator will be operational at all times or that emergency power will be available to the Premises when needed. Provided that Landlord provides an emergency generator with not less than the stated capacity of the Generator installed pursuant to Section 2 and contracts with a third party to maintain the Generator as per the manufacturer's standard maintenance guidelines as aforesaid, in no event shall Landlord be liable to Tenant or any other party for any damages of any type, whether actual or consequential, suffered by Tenant or any such other person in the event that the Generator or any replacement thereof fails or does not provide sufficient power.

        12.     Alterations and Tenant's Property.     Any alterations, additions, or improvements made to the Premises by or on behalf of Tenant, including additional locks or bolts of any kind or nature upon any doors or windows in the Premises, but excluding installation, removal or realignment of furniture systems (other than removal of furniture systems owned or paid for by Landlord) not involving any modifications to the structure or connections (other then by ordinary plugs or jacks) to Building Systems (as defined in Section 13 ) (" Alterations ") shall be subject to Landlord's prior written consent, which may be given or withheld in Landlord's sole discretion if any such Alteration affects the structure or Building Systems, but which shall otherwise not be unreasonably withheld or delayed. If Landlord approves any Alterations, Landlord may impose such conditions on Tenant in connection with the commencement, performance and completion of such Alterations as Landlord may deem appropriate in Landlord's reasonable discretion. Any request for approval shall be in writing, delivered not less than 15 business days in advance of any proposed construction, and accompanied by plans, specifications, bid proposals, work contracts and such other information concerning the nature and cost of the alterations as may be reasonably requested by Landlord, including the identities and mailing addresses of all persons performing work or supplying materials. Landlord's right to review plans and specifications and to monitor construction shall be solely for its own benefit, and Landlord shall have no duty to ensure that such plans and specifications or construction comply with applicable Legal Requirements. Tenant shall cause, at its sole cost and expense, all Alterations to comply with insurance requirements and with Legal Requirements and shall implement at its sole cost and expense any alteration or modification required by Legal Requirements as a result of any Alterations. Tenant shall pay to Landlord, as Additional Rent, on demand an amount equal to all actual out-of-pocket expenses incurred by Landlord in connection with plan review, coordination, scheduling and supervision. Before Tenant begins any Alteration, Landlord may post on and about the Premises notices of non-responsibility pursuant to applicable law. Tenant shall reimburse Landlord for, and indemnify and hold Landlord harmless from, any expense incurred by Landlord by reason of faulty work done by Tenant or its contractors, delays caused by such work, or inadequate cleanup.

        Tenant may construct nonstructural Alterations in the Premises without Landlord's prior approval if the aggregate cost of all such work in any 12 month period does not exceed $50,000 (a " Notice-Only Alteration "), provided Tenant notifies Landlord in writing of such intended Notice-Only Alteration, and such notice shall be accompanied by plans, specifications, work contracts and such other information concerning the nature and cost of the Notice-Only Alteration as may be reasonably requested by Landlord, which notice and accompanying materials shall be delivered to Landlord not less than 15 business days in advance of any proposed construction.

        Tenant shall timely pay for the completion of all Alterations work and shall keep the Premises free and clear of liens, and shall provide (and cause each contractor or subcontractor to provide) certificates of insurance for workers' compensation and other coverage in amounts and from an insurance company reasonably satisfactory to Landlord protecting Landlord against liability for personal injury or property

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damage during construction. Upon completion of any Alterations, Tenant shall deliver to Landlord: (i) sworn statements setting forth the names of all contractors and subcontractors who did the work and final lien waivers from all such contractors and subcontractors; and (ii) "as built" plans for any such Alteration.

        Other than (i) the items, if any, listed on Exhibit E attached hereto, (ii) any items agreed by Landlord in writing to be included on Exhibit E in the future, and (iii) any trade fixtures, machinery, equipment and other personal property not paid for out of the TI Fund (as defined in the TI Work Letter) which may be removed without material damage to the Premises, which damage shall be repaired (including capping or terminating utility hook-ups behind walls) by Tenant during the Term (collectively, " Tenant's Property "), all property of any kind paid for with the TI Fund, all Alterations, real property fixtures, built-in machinery and equipment, built-in casework and cabinets and other similar additions and improvements built into the Premises so as to become an integral part of the Premises such as fume hoods which penetrate the roof or plenum area, built-in cold rooms, built-in warm rooms, walk-in cold rooms, walk-in warm rooms, deionized water systems, glass washing equipment, autoclaves, chillers, built-in plumbing, electrical and mechanical equipment and systems, and any power generator and transfer switch (collectively, " Installations ") shall be and shall remain the property of Landlord during the Term and following the expiration or earlier termination of the Term, shall not be removed by Tenant at any time during the Term and shall remain upon and be surrendered with the Premises as a part thereof in accordance with Section 28 following the expiration or earlier termination of this Lease; provided, however , that Landlord shall, at the time its approval of such Installation is requested, notify Tenant if it has elected to require Tenant to remove such Installation upon the expiration or earlier termination of this Lease. If Landlord so elects, Tenant shall remove such Installation upon the expiration or earlier termination of this Lease and restore any damage caused by or occasioned as a result of such removal, including, when removing any of Tenant's Property which was plumbed, wired or otherwise connected to any of the Building Systems, capping off all such connections behind the walls of the Premises and repairing any holes. During any such restoration period, Tenant shall pay Rent to Landlord as provided herein as if said space were otherwise occupied by Tenant.

        13.     Landlord's Repairs.     Landlord, as an Operating Expense, shall maintain all of the structural, exterior (including exterior doors), parking and other areas of the Project outside of the Premises, including (i) the Air Handling System from and after the date of Substantial Completion (as defined in the AHS Work Letter) of the Air Handling System only (it being understood that prior to such date of Substantial Completion, all maintenance and repair of the existing HVAC system serving the Premises shall be the sole obligation of Tenant), and (ii) from and after the Commencement Date, the plumbing, fire sprinklers, elevators and all other building systems serving the Premises and other portions of the Project (which together with the existing HVAC system and from and after its Substantial Completion, the Air Handling System, are referred to herein as the " Building Systems "), in good repair, reasonable wear and tear and uninsured losses and damages caused by Tenant, or by any of Tenant's agents, servants, employees, invitees and contractors (collectively, " Tenant Parties ") excluded. Losses and damages caused by Tenant or any Tenant Party shall be repaired by Landlord, to the extent not covered by insurance, at Tenant's sole cost and expense. Landlord reserves the right to stop Building Systems services when necessary (i) by reason of accident or emergency, or (ii) for planned repairs, alterations or improvements, which are, in the reasonable judgment of Landlord, desirable or necessary to be made, until said repairs, alterations or improvements shall have been completed provided Landlord shall provide Tenant at least 48 hours' prior notice of such planned repairs. Landlord shall have no responsibility or liability for failure to supply Building Systems services during any such period of interruption; provided, however , that Landlord shall, except in case of emergency, make a commercially reasonable effort to give Tenant 48 hours advance notice of any planned stoppage of Building Systems services for routine maintenance, repairs, alterations or improvements. Tenant shall promptly give Landlord written notice of any repair required by Landlord pursuant to this Section, after which

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Landlord shall have a reasonable opportunity to effect such repair. Landlord shall not be liable for any failure to make any repairs or to perform any maintenance unless such failure shall persist for an unreasonable time after Tenant's written notice of the need for such repairs or maintenance. Tenant waives its rights under any state or local law to terminate this Lease or to make such repairs at Landlord's expense and agrees that the parties' respective rights with respect to such matters shall be solely as set forth herein. Repairs required as the result of fire, earthquake, flood, vandalism, war, or similar cause of damage or destruction shall be controlled by Section 18 .

        From and after the date of Substantial Completion of the Air Handling System (as such date is determined pursuant to the AHS Work Letter, in the event of a malfunction of the Air Handling System that in Tenant's reasonable judgment impacts Tenant's ability to operate its business in the Premises, Tenant shall have the right, exercisable as provided herein, to call the third-party contractor retained by Landlord to maintain the Air Handling System (the "Air Handling System Contractor" ) to repair the malfunction. Tenant shall give telephonic and written notice to Landlord immediately upon Tenant's calling the Air Handling System Contractor (such notice to be given no later than 24 hours from the time that Tenant called for service); provided that Landlord shall have no obligation to supervise, oversee or confirm that the Air Handling System Contractor is maintaining or repairing the Air Handling System as per the manufacturer's standard guidelines or otherwise. Within 24 hours of the arrival of the Air Handling System Contractor's technician or representative to the Premises, Tenant will provide Landlord with a written description of the nature of the malfunction (to the extent such technician has provided such information to Tenant), steps taken by the technician or representative, any direction given by the technician or representative regarding the Air Handling System and any other relevant information. Any charges to Landlord for response by the Air Handling System Contractor to such calls by Tenant in excess of the regular maintenance fees payable by Landlord under its agreement with the Air Handling System Contractor shall be paid by Tenant as Additional Rent upon delivery by Landlord to Tenant of an invoice for such charge, and all such invoices shall be paid by Tenant within 15 days.

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        14.     Tenant's Repairs.     Subject to Section 13 hereof, Tenant, at its expense, shall repair, replace and maintain in good condition all portions of the Premises, including, without limitation, entries, doors, ceilings, interior windows, interior walls, and the interior side of demising walls, and, until the Substantial Completion of the Air Handling System as provided in the AHS Work Letter, Tenant shall maintain and repair the existing HVAC system serving the Premises. Such repair and replacement may include capital expenditures and repairs whose benefit may extend beyond the Term. Should Tenant fail to make any such repair or replacement or fail to maintain the Premises, Landlord shall give Tenant notice of such failure. If Tenant fails to commence cure of such failure within 10 days of Landlord's notice, and thereafter diligently prosecute such cure to completion, Landlord may perform such work and shall be reimbursed by Tenant within 10 days after demand therefor; provided, however, that if such failure by Tenant creates or could create an emergency, Landlord may immediately commence cure of such failure and shall thereafter be entitled to recover the costs of such cure from Tenant. Subject to Sections 17 and 18 , Tenant shall bear the full uninsured cost of any repair or replacement to any part of the Project that results from damage caused by Tenant or any Tenant Party and any repair that benefits only the Premises.

        15.     Mechanic's Liens.     Tenant shall discharge, by bond or otherwise, any mechanic's lien filed against the Premises or against the Project for work claimed to have been done for, or materials claimed to have been furnished to, Tenant within 10 days after notice of, or becoming aware of, the filing thereof, at Tenant's sole cost and shall otherwise keep the Premises and the Project free from any liens arising out of work performed, materials furnished or obligations incurred by Tenant. Should Tenant fail to discharge any lien described herein, Landlord shall have the right, but not the obligation, to pay such claim or post a bond or otherwise provide security to eliminate the lien as a claim against title to the Project and the cost thereof shall be immediately due from Tenant as Additional Rent. If Tenant shall lease or finance the acquisition of office equipment, furnishings, or other personal property of a removable nature utilized by Tenant in the operation of Tenant's business, Tenant warrants that any Uniform Commercial Code Financing Statement filed as a matter of public record by any lessor or creditor of Tenant will upon its face or by exhibit thereto indicate that such Financing Statement is applicable only to removable personal property of Tenant located within the Premises. In no event shall the address of the Project be furnished on the statement without qualifying language as to applicability of the lien only to removable personal property, located in an identified suite held by Tenant.

        16.     Indemnification.     Tenant hereby indemnifies and agrees to defend, save and hold Landlord harmless from and against any and all Claims for injury or death to persons or damage to property occurring within or about the Premises, arising directly or indirectly out of Tenants' use or occupancy of the Premises or a breach or default by Tenant in the performance of any of its obligations hereunder, unless caused solely by the willful misconduct or negligence of Landlord. Landlord shall not be liable to Tenant for, and Tenant assumes all risk of damage to, personal property (including, without limitation, loss of records kept within the Premises). Tenant further hereby irrevocably waives any and all Claims for injury to Tenant's business or loss of income relating to any such damage or destruction of personal property (including, without limitation, any loss of records), unless caused by the willful misconduct or negligence of Landlord, its officers, directors, employees, managers, agents, invitees and contractors (collectively, "Landlord Parties" ). Landlord shall not be liable for any damages arising from any act, omission or neglect of any tenant in the Project or of any other third party.

        17.     Insurance.     Landlord shall maintain all risk property and, if applicable, sprinkler damage insurance covering the full replacement cost of the Project. Landlord shall further procure and maintain commercial general liability insurance with a single loss limit of not less than $2,000,000 for bodily injury and property damage with respect to the Project. Landlord may, but is not obligated to, maintain such other insurance and additional coverages as it may deem necessary, including, but not limited to, flood, environmental hazard and earthquake, loss or failure of building equipment, errors

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and omissions, rental loss during the period of repair or rebuilding, workers' compensation insurance and fidelity bonds for employees employed to perform services and insurance for any improvements installed by Tenant or which are in addition to the standard improvements customarily furnished by Landlord without regard to whether or not such are made a part of the Project. All such insurance shall be included as part of the Operating Expenses. The Project may be included in a blanket policy (in which case the cost of such insurance allocable to the Project will be reasonably determined by Landlord based upon the insurer's cost calculations). Tenant shall also reimburse Landlord, as Additional Rent, for any increased premiums or additional insurance which Landlord reasonably deems necessary as a result of Tenant's use of the Premises.

        Tenant, at its sole cost and expense, shall maintain during the Term: all risk property insurance with business interruption and extra expense coverage, covering the full replacement cost of all property and improvements installed or placed in the Premises by Tenant at Tenant's expense; workers' compensation insurance with no less than the minimum limits required by law; employer's liability insurance with such limits as required by law; and commercial general liability insurance, with a minimum limit of not less than $2,000,000 per occurrence for bodily injury and property damage with respect to the Premises. The commercial general liability insurance policy shall name Landlord and Alexandria Real Estate Equities, Inc. as additional insureds; insure on an occurrence and not a claims-made basis; be issued by insurance companies which have a rating of not less than policyholder rating of A and financial category rating of at least Class X in "Best's Insurance Guide"; shall not be cancelable for nonpayment of premium unless 30 days prior written notice shall have been given to Landlord from the insurer; contain a hostile fire endorsement and a contractual liability endorsement; and provide primary coverage to Landlord (any policy issued to Landlord providing duplicate or similar coverage shall be deemed excess over Tenant's policies). Copies of such policies (if requested by Landlord), or certificates of insurance showing the limits of coverage required hereunder and showing Landlord as an additional insured, along with reasonable evidence of the payment of premiums for the applicable period, shall be delivered to Landlord by Tenant upon commencement of the Term and upon each renewal of said insurance. Tenant's policy may be a "blanket policy" with an aggregate per location endorsement which specifically provides that the amount of insurance shall not be prejudiced by other losses covered by the policy. Tenant shall, at least 5 days prior to the expiration of such policies, furnish Landlord with renewal certificates.

        In each instance where insurance is to name Landlord as an additional insured, Tenant shall upon written request of Landlord also designate and furnish certificates so evidencing Landlord as additional insured to: (i) any lender of Landlord holding a security interest in the Project or any portion thereof, (ii) the landlord under any lease wherein Landlord is tenant of the real property on which the Project is located, if the interest of Landlord is or shall become that of a tenant under a ground or other underlying lease rather than that of a fee owner, and/or (iii) any management company retained by Landlord to manage the Project.

        The property insurance obtained by Landlord and Tenant shall include a waiver of subrogation by the insurers and all rights based upon an assignment from its insured, against Landlord or Tenant, and their respective officers, directors, employees, managers, agents, invitees and contractors (" Related Parties "), in connection with any loss or damage thereby insured against. Notwithstanding the provisions of Section 16, neither party nor its respective Related Parties shall be liable to the other for loss or damage caused by any risk insured against under property insurance required to be maintained hereunder, and each party waives any claims against the other party, and its respective Related Parties, for such loss or damage. The failure of a party to insure its property shall not void this waiver. Landlord and its respective Related Parties shall not be liable for, and Tenant hereby waives all claims against such parties for, business interruption and losses occasioned thereby sustained by Tenant or any person claiming through Tenant resulting from any accident or occurrence in or upon the Premises or the Project, except to the extent such loss is caused by the negligence or willful misconduct of Landlord

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or any Landlord Party. If the foregoing waivers shall contravene any law with respect to exculpatory agreements, the liability of Landlord or Tenant shall be deemed not released but shall be secondary to the other's insurer.

        Landlord may require insurance policy limits to be raised to conform with requirements of Landlord's lender and/or to bring coverage limits to levels then being generally required of new tenants within the Project.

        18.     Restoration.     If, at any time during the Term, the Project or the Premises are damaged or destroyed by a fire or other insured casualty, Landlord shall notify Tenant within 60 days after discovery of such damage as to the amount of time Landlord reasonably estimates it will take to restore the Project or the Premises, as applicable (the " Restoration Period "). If the Restoration Period following a fire or other casualty is estimated to exceed 12 months (the " Maximum Restoration Period "), either Landlord or Tenant may elect to terminate this Lease as of the date that is 75 days after the date of discovery of such damage or destruction. Unless Landlord or Tenant so elects to terminate this Lease, Landlord shall, subject to receipt of sufficient insurance proceeds (with any deductible to be treated as a current Operating Expense), promptly restore the Premises (excluding the improvements installed by Tenant or by Landlord and paid for by Tenant, subject to delays arising from the collection of insurance proceeds, from Force Majeure events or as needed to obtain any license, clearance or other authorization of any kind required to enter into and restore the Premises issued by any Governmental Authority having jurisdiction over the use, storage, handling, treatment, generation, release, disposal, removal or remediation of Hazardous Materials (as defined in Section 30 ) in, on or about the Premises (collectively referred to herein as " Hazardous Materials Clearances "); provided , however , that if repair or restoration of the Premises is not substantially complete as of the end of the Maximum Restoration Period or, if longer, the Restoration Period, Landlord may, in its sole and absolute discretion, elect to terminate this Lease, or Tenant may by written notice to Landlord delivered within 5 business days of the expiration of the Maximum Restoration Period or, if longer, the Restoration Period, elect to terminate this Lease, in either of which events Landlord shall be relieved of its obligation to make such rep