Exhibit 10.13

EXECUTION COPY

LEASE

321 SUMMER STREET LLC,

Landlord,

and

INOZYME PHARMA, INC.,

Tenant

TABLE OF CONTENTS

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TABLE OF CONTENTS

(continued)

EXHIBIT A-1 – FLOOR PLAN DEPICTING THE PREMISES

EXHIBIT B – WORK LETTER

SCHEDULE 3

INTENTIONALLY OMITTED

EXHIBIT C – COMMENCEMENT DATE MEMORANDUM

EXHIBIT D – RULES AND REGULATIONS

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GROSS (BY)-INS OFFICE LEASE

REFERENCE PAGES

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Month 1 is the period beginning on the Rent Commencement Date and ending at the end of the first (1st) full calendar month thereafter (by way of example only, if the Rent Commencement Date were December 1, 2019, Month 1 would be the period December 1, 2019 through December 31, 2019; if the Rent Commencement Date were December 15, 2019, Month 1 would be the period

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from December 15, 2019 through January 31, 2020). Month 2 is the calendar month period immediately following Month 1; Month 3 is the calendar month following Month 2; and so forth, up to the Termination Date.

The actual dates are to be confirmed pursuant to Section 2.1.

All rental amounts are net of Tenant electricity.

The Reference Pages information is incorporated into and made a part of the Lease. In the event of any conflict between any Reference Pages information and the Lease, the Lease shall control. This Lease includes Exhibits A through D, all of which are made a part of this Lease.

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IN WITNESS WHEREOF, Landlord and Tenant have executed the Lease as of the Lease Reference Date set forth above.

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LEASE

By this Lease Landlord leases to Tenant and Tenant leases from Landlord the Premises in the Building as set forth and described on the Reference Pages. The Premises are depicted on the floor plan attached hereto as Exhibit A-1, and the Building is located on the Lot legally described on Exhibit A-2. The Reference Pages, including all terms defined thereon, are incorporated as part of this Lease.

1.    USE AND RESTRICTIONS ON USE.

1.1    The Premises are to be used solely for general office purposes. Tenant shall not do or permit anything to be done in or about the Premises which will in any way obstruct or interfere with the rights of other tenants or occupants of the Building or injure, annoy, or disturb them, or allow the Premises to be used for any improper, immoral, unlawful, or objectionable purpose, or commit any waste. Tenant shall not do, permit or suffer in, on, or about the Premises the sale of any alcoholic liquor without the written consent of Landlord first obtained. Tenant shall comply with all federal, state and city laws, codes, ordinances, rules and regulations (collectively, “Regulations”) applicable to the use of the Premises and its occupancy and shall promptly comply with all governmental orders and directions for the correction, prevention and abatement of any violations in the Building or appurtenant land, caused or permitted by, or resulting from the specific use by, Tenant, or in or upon, or in connection with, the Premises, all at Tenant’s sole expense. Tenant shall not do or permit anything to be done on or about the Premises or bring or keep anything into the Premises which will in any way increase the rate of, invalidate or prevent the procuring of any insurance protecting against loss or damage to the Building or any of its contents by fire or other casualty or against liability for damage to property or injury to persons in or about the Building or any part thereof. Tenant shall not bring upon the Premises or any portion of the Building or use the Premises or permit the Premises or any portion thereof to be used for the growing, manufacturing, administration, distribution (including without limitation, any retail sales), possession, use or consumption of any cannabis, marijuana or cannabinoid product or compound, regardless of the legality or illegality of the same.

1.2    Tenant shall not, and shall not direct, suffer or permit any of its agents, contractors, employees, licensees or invitees (collectively, the “Tenant Entities”) to at any time handle, use, manufacture, store or dispose of in or about the Premises or the Building any (collectively “Hazardous Materials”) flammables, explosives, radioactive materials, hazardous wastes or materials, toxic wastes or materials, or other similar substances, petroleum products or derivatives or any substance subject to regulation by or under any federal, state and local laws and ordinances relating to the protection of the environment or the keeping, use or disposition of environmentally hazardous materials, substances, or wastes, presently in effect or hereafter adopted, all amendments to any of them, and all rules and regulations issued pursuant to any of such laws or ordinances (collectively “Environmental Laws”), nor shall Tenant suffer or permit any Hazardous Materials to be used in any manner not fully in compliance with all Environmental Laws, in the Premises or the Building and appurtenant land or allow the environment to become contaminated with any Hazardous Materials. Notwithstanding the foregoing, Tenant may handle, store, use or dispose of products containing small quantities of Hazardous Materials (such as aerosol cans containing insecticides, toner for copiers, paints, paint remover and the like) to the extent customary and necessary for the use of the Premises for general office purposes; provided that Tenant shall always handle, store, use, and dispose of any such Hazardous Materials in a safe and lawful manner and never allow such Hazardous Materials to contaminate the Premises, Building and appurtenant land or the environment. Tenant shall protect, defend, indemnify and hold each and all of the Landlord Entities (as defined in Article 301) harmless from and against any and all loss, claims, liability or costs (including court costs and attorney’s fees) incurred by reason of any actual or asserted failure of Tenant to fully comply with all applicable Environmental Laws, or the presence, handling, use or disposition in or from the Premises of any

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Hazardous Materials by Tenant or any Tenant Entity (even though permissible under all applicable Environmental Laws or the provisions of this Lease), or by reason of any actual or asserted failure of Tenant to keep, observe, or perform any provision of this Section 1.2.

1.3    Tenant and the Tenant Entities will be entitled to the non-exclusive use of the common areas of the Building as they exist from time to time during the Term, including the parking facilities, subject to Landlord’s reasonable rules and regulations regarding such use. However, in no event will Tenant or the Tenant Entities park more vehicles in the parking facilities than the number of parking passes allocated to Tenant in the Reference Pages of this Lease. The foregoing shall not be deemed to provide Tenant with an exclusive right to any parking spaces or any guaranty of the availability of any particular parking spaces or any specific number of parking spaces.

Such rights shall always be subject to the Rules and Regulations set forth in Exhibit D as the same may be reasonably amended by the Landlord from time to time, and such other reasonable rules and regulations from time to time established by Landlord by suitable notice, and to the right of Landlord to designate and change from time to time areas and facilities so to be used, provided such designations and changes do not deprive Tenant of the substantive benefits of such areas and facilities.

Not included in the Premises are the ceiling, the floor and all perimeter walls of the space identified in Exhibit A, except the inner surfaces thereof and the perimeter doors and windows. Tenant agrees that Landlord shall have the right to place in the Premises (but in such manner as not unreasonably to interfere with Tenant’s use of the Premises or materially alter the Premises) utility lines, telecommunication lines, shafts, pipes and the like, for the use and benefit of Landlord and other tenants in the Building, and to replace and maintain and repair such lines, pipes and the like, in, over and upon the Premises. Such utility lines, pipes and the like, shall not be deemed part of the Premises under this Lease.

1.4    If the Building is being operated in accordance with Green Building Standards, Landlord shall provide bicycle storage racks and may, in its discretion elect to establish preferred parking programs for hybrid and alternative fuel vehicles.

1.5    Tenant shall have the right to Building standard signage on the lobby directory at no charge. Tenant’s logo can be installed or applied at Tenant’s sole cost only on the glass storefront and not on any common walls. Tenant shall remove such logo at the expiration or earlier termination of the Lease Term.

1.6    Tenant shall have access to the Premises on a 24 hour basis, 365 days per year, subject to the terms of this Lease. Tenant may install an internal security system for the Premises, but such system shall tie into and be compatible with the Building fire alarm system.

2.    TERM.

2.1    The Term of this Lease shall begin on the date (“Commencement Date”) which shall be the Substantial Completion Date (as defined in Exhibit B attached hereto), and shall terminate on the date as shown on the Reference Pages as the Termination Date based on the actual Commencement Date (“Termination Date”), unless sooner terminated by the provisions of this Lease. Landlord shall tender possession of the Premises with (i) all HVAC, mechanical, electrical, lighting and life safety systems serving the Building and Premises in good working condition, in good repair, in compliance with all applicable laws, rules and regulations; and (ii) the Landlord’s Work to be performed by Landlord pursuant to Exhibit B to this Lease “Substantially Completed” (as such term is defined in Exhibit B), subject to any

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Tenant Delays (as defined in Exhibit B attached hereto). Tenant and Landlord shall conduct a joint walk-through of the Premises and create a punch list of items not completed within thirty (30) days after Landlord tenders possession of the Premises and Landlord agrees to proceed with due diligence to perform its obligations regarding such items. Tenant shall, at Landlord’s request, execute and deliver a memorandum agreement provided by Landlord in the form of Exhibit C attached hereto, setting forth the actual Commencement Date, Termination Date and, if necessary, a revised rent schedule. Should Tenant fail to do so within thirty (30) days after Landlord’s request, the information set forth in such memorandum provided by Landlord shall be conclusively presumed to be agreed and correct.

2.2    Tenant agrees that in the event of the inability of Landlord to deliver possession of the Premises on the Scheduled Commencement Date for any reason, Landlord shall not be liable for any damage resulting from such inability, but except to the extent such delay is the result of a Tenant Delay, Tenant shall not be liable for any rent until the time when Landlord delivers possession of the Premises to Tenant. Notwithstanding the foregoing, in the event that this Lease is executed and delivered by Tenant to Landlord on or before December 9, 2019 and Landlord has not delivered possession of the Premises to Tenant on or before May 15, 2020 (the “First Abatement Date”), Tenant shall be entitled to one-half day of free rent for each day from the First Abatement Date through May 31, 2020 that Landlord fails to deliver possession of the Premises to Tenant (with the accrued free rent to be credited to Tenant in Month 4), provided the First Abatement Date shall be extended on a day for day basis for (a) each day after December 9, 2019 that Tenant has not executed and delivered this Lease to Landlord and (b) for each day in completing the Landlord’s Work caused by Tenant Delays or Force Majeure Delays. If this Lease is executed and delivered by Tenant to Landlord on or before December 9, 2019 and Landlord has not delivered possession of the Premises to Tenant on or before June 1, 2020 (the “Second Abatement Date”), Tenant shall be entitled to one day of free rent for each day between June 1, 2020 through June 15, 2020 that Landlord fails to deliver possession of the Premises to Tenant (with the accrued free rent to be credited to Tenant in Month 4), provided the Second Abatement Date shall be extended on a day for day basis for (a) each day after December 9, 2019 that Tenant has not executed and delivered this Lease to Landlord and (b) for each day in completing the Landlord’s Work caused by Tenant Delays or Force Majeure Delays. If this Lease is executed and delivered by Tenant to Landlord on or before December 9, 2019 and Landlord has not delivered possession of the Premises to Tenant on or before June 16, 2020 (the “Third Abatement Date”), Tenant shall be entitled to two days of free rent for each day after June 16, 2020 that Landlord fails to deliver possession of the Premises to Tenant (with the accrued free rent to be credited to Tenant in Month 4), provided the Third Abatement Date shall be extended on a day for day basis for (a) each day after December 9, 2019 that Tenant has not executed and delivered this Lease to Landlord and (b) for each day in completing the Landlord’s Work caused by Tenant Delays or Force Majeure Delays. In addition to the foregoing free rent penalty, Tenant shall be entitled to terminate this Lease by providing written notice to Landlord if the Landlord has not delivered possession of the Premises to Tenant on or before August 31, 2019 (the “Delay Termination Date”) and, if such right is exercised by Tenant, this Lease shall be immediately terminated and Landlord shall promptly turn over all amounts previously paid by Tenant hereunder (including, but not limited to, the Security Deposit), provided the Delay Termination Date shall be extended on a day for day basis for (a) each day after December 9, 2019 that Tenant has not executed and delivered this Lease to Landlord and (b) for each day in completing the Landlord’s Work caused by Tenant Delays or Force Majeure Delays. No such failure to give possession on the Scheduled Commencement Date shall affect the other obligations of Tenant under this Lease, except that the actual Commencement Date shall be postponed until the date that Landlord delivers possession of the Premises to Tenant, except to the extent that such delay is arising from or related to a Tenant Delay. If any delay is the result of a Tenant Delay, the Commencement Date and the payment of rent under this Lease shall be accelerated by the number of days of such Tenant Delay.

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2.3    Landlord shall permit Tenant to access the Premises approximately thirty (30) days prior to the Commencement Date for purposes of installation of tel/data cabling and furniture, fixtures and equipment, provided such early access shall not interfere with Landlord’s Work. Any such early access to the Premises by any agent, employee or contractor of Tenant, prior to the Commencement Date shall be subject to all the provisions of this Lease other than the payment of rent, including, without limitation, Tenant’s compliance with the insurance requirements of Article 11. Said early possession shall not advance the Rent Commencement Date or the Termination Date.

3.    RENT.

3.1    Tenant agrees to pay to Landlord the Annual Rent in effect from time to time by paying the Monthly Installment of Rent then in effect on or before the first day of each full calendar month during the Term, except that the first full month’s rent shall be paid upon the execution of this Lease. The Monthly Installment of Rent in effect at any time shall be one-twelfth (1/12) of the Annual Rent in effect at such time. Rent for any period during the Term which is less than a full month shall be a prorated portion of the Monthly Installment of Rent based upon the number of days in such month. Said rent shall be paid to Landlord, without deduction or offset and without notice or demand, at the Rent Payment Address, as set forth on the Reference Pages, or by ACH or to such other person or at such other place as Landlord may from time to time designate in writing. If an Event of Default occurs, Landlord may require by notice to Tenant that all subsequent rent payments be made by an ACH or wire transfer from Tenant’s bank account to Landlord’s account, without cost to Landlord. Tenant must implement such automatic payment system prior to the next scheduled rent payment or within ten (10) days after Landlord’s notice, whichever is later. Unless specified in this Lease to the contrary, all amounts and sums payable by Tenant to Landlord pursuant to this Lease shall be deemed additional rent.

3.2    Tenant recognizes that late payment of any rent or other sum due under this Lease will result in administrative expense to Landlord, the extent of which additional expense is extremely difficult and economically impractical to ascertain. Tenant therefore agrees that if rent or any other sum is not paid when due and payable pursuant to this Lease, a late charge shall be imposed in the amount that is the greater of: (a) Fifty Dollars ($50.00), or (b) six percent (6%) of the unpaid rent or other payment; provided, however, the first late payment under this Lease in any calendar year, if timely cured, shall be not be assessed any late charge under this Section 3.2. The amount of the late charge to be paid by Tenant shall be reassessed and added to Tenant’s obligation for each successive month until paid. The provisions of this Section 3.2 in no way relieve Tenant of the obligation to pay rent or other payments on or before the date on which they are due, nor do the terms of this Section 3.2 in any way affect Landlord’s remedies pursuant to Article 19 of this Lease in the event said rent or other payment is unpaid after date due.

3.3    Tenant hereby acknowledges and agrees that the obligations of Tenant hereunder shall be separate and independent covenants and agreements, that rent shall continue to be payable in all events and that the obligations of Tenant hereunder shall continue unaffected, unless the requirement to pay or perform the same shall have been terminated or abated pursuant to an express provision of this Lease. Landlord and Tenant each acknowledges and agrees that the independent nature of the obligations of Tenant hereunder represents fair, reasonable, and accepted commercial practice with respect to the type of property subject to this Lease. Such acknowledgements by Tenant are a material inducement to Landlord entering into this Lease.

4.    RENT ADJUSTMENTS.

4.1    For the purpose of this Article 4, the following terms are defined as follows:

4.1.1    Lease Year: Each fiscal year (as determined by Landlord from time to time) falling partly or wholly within the Term.

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4.1.2    Expenses: All costs of operation, maintenance, repair, replacement and management of the Building (including the amount of any credits which Landlord may grant to particular tenants of the Building in lieu of providing any standard services or paying any standard costs described in this Section 4.1.2 for similar tenants), as determined in accordance with generally accepted accounting principles, including the following costs by way of illustration, but not limitation: costs to obtain and maintain certification for Green Building Standards (excluding capital expenditure retrofitting or replacement costs to conform with certification requirements); water and sewer charges; utility costs, including, but not limited to, the cost of heat, light, power, steam, gas and energy for the Building; waste disposal; recycling costs; the cost of janitorial services; the cost of security and alarm services (including any central station signaling system); costs of cleaning, repairing, replacing and maintaining the common areas, including parking and landscaping, window cleaning costs; labor costs; costs and expenses of managing the Building including management and/or administrative fees; air conditioning maintenance costs; elevator maintenance fees and supplies; material costs; equipment costs including the cost of maintenance, repair and service agreements and rental and leasing costs; purchase costs of equipment; current rental and leasing costs of items which would be capital items if purchased; tool costs; licenses, permits and inspection fees; wages and salaries of employees directly and primarily engaged in the management and operation of the Building; employee benefits and payroll taxes; accounting and legal fees; any sales, use or service taxes incurred in connection therewith. In addition, Landlord shall be entitled to recover, as additional rent (which, along with any other capital expenditures constituting Expenses, Landlord may either include in Expenses or cause to be billed to Tenant along with Expenses and Taxes but as a separate item), Tenant’s Proportionate Share of: (a) an allocable portion of the cost of capital improvement items which are reasonably calculated to reduce operating expenses or enhance the environmental sustainability of the Property’s operations; (b) the cost of fire sprinklers and suppression systems and other life safety systems and other capital other capital expenses which are required under any Regulations which were not applicable to the Building at the time it was constructed; but the costs described in this sentence shall be amortized over the reasonable life of such the capital item related to each such expenditure in accordance with such reasonable life and amortization schedules as shall be determined by Landlord in accordance with generally accepted accounting principles, with interest on the unamortized amount at one percent (1%) in excess of the Wall Street Journal prime lending rate announced from time to time. Expenses shall not include any of the following: (i) Taxes, (ii) Insurance Costs, (iii) depreciation or amortization of the Building or equipment in the Building except as provided herein, (iv) loan principal payments, (v) costs of alterations of tenants’ premises, (vi) leasing commissions, (vii) interest expenses on long-term borrowings or advertising costs, (viii) rental on ground leases or other underlying leases and the costs of providing the same, (ix) any liabilities, costs or expenses associated with or incurred in connection with the removal, enclosure, encapsulation or other handling of hazardous materials and the cost of defending against claims in regard to the existence or release of hazardous materials at the Building (except with respect to those costs for which Tenant is otherwise responsible pursuant to the express terms of this Lease), (x) costs of any items for which Landlord is or is entitled to be paid or reimbursed by insurance, (xi) charges for electricity, water, or other utilities, services or goods and applicable taxes for which Tenant or any other tenant, occupant, person or other party is obligated to reimburse Landlord or to pay to third parties, (xii) cost of any HVAC, janitorial or other services provided to tenants on an extra cost basis after regular business hours, (xiii) the cost of installing, operating and maintaining any specialty service, such as a cafeteria, observatory, broadcasting facilities, child or daycare (but the parties agree that upon the introduction of any such service the Base Year (Expenses) shall be increased to include the first year’s annual costs of such services), (xiv) cost of correcting defects in the design, construction or equipment of, or latent defects in, the Building, (xv) cost

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of any work or service performed on an extra cost basis for any tenant in the Building to a materially greater extent or in a materially more favorable manner than furnished generally to the tenants and other occupants, (xvi) cost of any work or services performed for any facility other than the Building, (xvii) any cost representing an amount paid to a person firm, corporation or other entity related to Landlord that is in excess of the amount which would have been paid in the absence of such relationship, (xviii) cost of initial cleaning and rubbish removal from the Building to be performed before final completion of the Building or Premises, (xix) except as expressly provided above, cost of any item that, under generally accepted accounting principles, are properly classified as capital expenses, (xx) lease payments for rental equipment (other than equipment for which depreciation is properly charged as an expense) that would constitute a capital expenditure if the equipment were purchased, (xxi) cost of the initial stock of tools and equipment for operation, repair and maintenance of the Building, (xxiii) late fees or charges incurred by Landlord due to late payment of expenses, except to the extent attributable to Tenant’s actions or inactions, (xxiii) cost of acquiring, securing cleaning or maintaining sculptures, paintings and other works of art, (xxiv) real estate taxes or taxes on Landlord’s business (such as income, excess profits, franchise, capital stock, estate, inheritance, etc.), (xxv)direct costs or allocable costs (such as real estate taxes) associated with parking operations if there is a separate charge to Tenant, other than tenants or the public for parking, (xxvi) charitable or political contributions, (xxvii) reserve funds, (xxiii) all other items for which another party compensates or pays so that Landlord shall not recover any item of cost more than once, (xxix) any cost associated with operating as an on or off-site management office for the Building, except to the extent included in the management fee permitted hereby, (xxx) Landlord’s general overhead and any other expenses not directly attributable to the operation and management of the Building (e.g. the activities of Landlord’s officers and executives or professional development expenditures), except to the extent included in the management fee permitted hereby, (xxxi) costs and expenses incurred in connection with compliance with or contesting or settlement of any claimed violation of law or requirements of law, except to the extent attributable to Tenant’s actions or inactions, and/or (xxxii) costs of mitigation or impact fees or subsidies (however characterized), imposed or incurred prior to the date of the Lease or imposed or incurred solely as a result of another tenant’s or tenants’ use of the Building or their respective premises.

4.1.3    Taxes: Real estate taxes and any other taxes, charges and assessments which are levied with respect to the Building or the land appurtenant to the Building, or with respect to any improvements, fixtures and equipment or other property of Landlord, real or personal, located in the Building and used in connection with the operation of the Building and said land, any payments to any ground lessor in reimbursement of tax payments made by such lessor; and all fees, expenses and costs incurred by Landlord in investigating, protesting, contesting or in any way seeking to reduce or avoid increase in any assessments, levies or the tax rate pertaining to any Taxes to be paid by Landlord in any Lease Year. Taxes shall be determined without regard to any “green building” credit and shall not include any corporate franchise, or estate, inheritance or net income tax, or documentary transfer tax imposed upon any transfer by Landlord of its interest in this Lease or the Building or any taxes to be paid by Tenant pursuant to Article 28.

4.1.4    Insurance Costs: Any and all insurance charges of or relating to all insurance policies and endorsements deemed by Landlord to be reasonably necessary or desirable and relating in any manner to the protection, preservation, or operation of the Building or any part thereof.

4.2    If in any Lease Year, (i) Expenses paid or incurred shall exceed Expenses paid or incurred in the Base Year (Expenses) and/or (ii) Taxes paid or incurred by Landlord in any Lease Year shall exceed the amount of such Taxes which became due and payable in the Base Year (Taxes), and/or (iii) Insurance Costs paid or incurred by Landlord in any Lease Year shall exceed the amount of such Insurance Costs which became due and payable in the Base Year (Insurance), Tenant shall pay as additional rent for such Lease Year Tenant’s Proportionate Share of each such excess amount.

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4.3    The annual determination of Expenses and Insurance Costs shall be made by Landlord and shall be binding upon Landlord and Tenant, subject to the provisions of this Section 4.3. Landlord may deliver such annual determination to Tenant via regular U.S. mail. During the Term, Tenant may review, at Tenant’s sole cost and expense, the books and records supporting such determination in an office of Landlord, or Landlord’s agent, during normal business hours, upon giving Landlord five (5) days advance written notice within one hundred twenty (120) days after receipt of such determination, but in no event more often than once in any one (1) year period, subject to execution of a confidentiality agreement acceptable to Landlord, and provided that if Tenant utilizes an independent accountant to perform such review who is acceptable to Landlord in the exercise of its reasonable discretion (which determination shall be made by Landlord within ten (10) business days after request), is not compensated on a contingency basis and is also subject to such confidentiality agreement. If Tenant fails to object to Landlord’s determination of Expenses and Insurance Costs within one hundred eighty (180) days after receipt, or if any such objection fails to state with specificity the reason for the objection, Tenant shall be deemed to have approved such determination and shall have no further right to object to or contest such determination. In the event that during all or any portion of any Lease Year or Base Year, the Building is not fully rented and occupied Landlord shall make an appropriate adjustment in occupancy-related Expenses for such year for the purpose of avoiding distortion of the amount of such Expenses to be attributed to Tenant by reason of variation in total occupancy of the Building, by employing consistent and sound accounting and management principles to determine Expenses that would have been paid or incurred by Landlord had the Building been ninety-five percent (95%) rented and occupied, and the amount so determined shall be deemed to have been Expenses for such Lease Year.

4.4    Prior to the actual determination thereof for a Lease Year, Landlord may from time to time estimate Tenant’s liability for Expenses, Insurance Costs and/or Taxes under Section 4.2, Article 6 and Article 28 for the Lease Year or portion thereof. Landlord will give Tenant written notification of the amount of such estimate and Tenant agrees that it will pay, by increase of its Monthly Installments of Rent due in such Lease Year, additional rent in the amount of such estimate. Any such increased rate of Monthly Installments of Rent pursuant to this Section 4.4 shall remain in effect until further written notification to Tenant pursuant hereto.

4.5    When the above mentioned actual determination of Tenant’s liability for Expenses, Insurance Costs and/or Taxes is made for any Lease Year and when Tenant is so notified in writing, then:

4.5.1    If the total additional rent Tenant actually paid pursuant to Section 4.3 on account of Expenses, Insurance Costs and/or Taxes for the Lease Year is less than Tenant’s liability for Expenses, Insurance Costs and/or Taxes, then Tenant shall pay such deficiency to Landlord as additional rent in one lump sum within thirty (30) days of receipt of Landlord’s bill therefor; and

4.5.2    If the total additional rent Tenant actually paid pursuant to Section 4.3 on account of Expenses, Insurance Costs and/or Taxes for the Lease Year is more than Tenant’s liability for Expenses, Insurance Costs and/or Taxes, then Landlord shall credit the difference against the then next due payments to be made by Tenant under this Article 4, or, if the Lease has terminated, refund the difference in cash. Tenant shall not be entitled to a credit by reason of actual Expenses and/or Taxes and/or Insurance Costs in any Lease Year being less than Expenses and/or Taxes and/or Insurance Costs in the Base Year (Expenses and/or Taxes and/or Insurance).

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4.6    If the Commencement Date is other than January 1 or if the Termination Date is other than December 31, Tenant’s liability for Expenses, Insurance Costs and Taxes for the Lease Year in which said Date occurs shall be prorated based upon a three hundred sixty-five (365) day year.

5.    SECURITY DEPOSIT.

5.1    Tenant shall deposit the Security Deposit with Landlord upon the execution of this Lease. Said sum shall be held by Landlord as security for the faithful performance by Tenant of all the terms, covenants and conditions of this Lease to be kept and performed by Tenant and not as an advance rental deposit or as a measure of Landlord’s damage in case of Tenant’s default. If Tenant defaults with respect to any provision of this Lease, Landlord may use any part of the Security Deposit for the payment of any rent or any other sum in default, or for the payment of any amount which Landlord may spend or become obligated to spend by reason of Tenant’s default, or to compensate Landlord for any other loss or damage which Landlord may suffer by reason of Tenant’s default. If any portion is so used, Tenant shall within ten (10) days after written demand therefor, deposit with Landlord an amount sufficient to restore the Security Deposit to its original amount and Tenant’s failure to do so shall be a material breach of this Lease. Except to such extent, if any, as shall be required by law, Landlord shall not be required to keep the Security Deposit separate from its general funds, and Tenant shall not be entitled to interest on such deposit. If Tenant shall fully and faithfully perform every provision of this Lease to be performed by it, the Security Deposit or any balance thereof shall be returned to Tenant at such time after termination of this Lease when Landlord shall have determined that all of Tenant’s obligations under this Lease have been fulfilled.

5.2    The required Security Deposit shall be provided in cash or in the form of an Irrevocable Standby Letter of Credit in favor of Landlord (the “letter of credit”) in the amount set forth on the Reference Pages. Under any circumstance under which Landlord is entitled the use of all or a part of the Security Deposit, then, Landlord, in addition to all other rights and remedies provided under the Lease, shall have the right to draw down all or a portion of the full balance of the letter of credit and retain the proceeds. The following terms and conditions shall govern the letter of credit:

5.2.1    Upon expiration of the Term, the letter of credit shall be returned to Tenant when Tenant is entitled to return of its Security Deposit.

5.2.2    The letter of credit shall be in favor of Landlord, shall be issued by a commercial bank reasonably acceptable to Landlord, shall comply with all of the terms and conditions of this Section 5.2 and shall otherwise be in form reasonably acceptable to Landlord. Without limiting the generality of the foregoing, (i) the letter of credit must provide for all notices to the beneficiary to be sent simultaneously to up to two (2) addressees specified in the letter of credit, and (ii) there shall be no requirement of signature guaranty for draws, assignments or other documentary action to be taken by the beneficiary. If, at any time while the letter of credit is outstanding, (i) the issuing bank is declared insolvent or taken into receivership by the Federal Deposit Insurance Corporation or any other governmental agency, or is closed for any reason, or (ii) Landlord reasonably believes that the issuing bank may be or become insolvent or otherwise unable to meet its obligations, then, not later than thirty (30) days after written notice from Landlord, Tenant shall cause the existing letter of credit to be replaced by a new letter of credit issued by another commercial bank reasonably acceptable to Landlord, with such new letter of credit to comply with all of the terms and conditions of this Section 5.2. If Tenant fails to deliver an acceptable replacement letter of credit within such 30 day period, Landlord shall have the right to present the existing letter of credit to the issuing bank for payment, and the entire sum so obtained shall be paid to Landlord, to be held by Landlord until Tenant would otherwise be entitled to the return of the letter of credit, and to be retained by Landlord if a default occurs.

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5.2.3    The initial letter of credit shall have an expiration date not earlier than fifteen (15) months after the Commencement Date. A draft of the form of letter of credit must be submitted to Landlord for its approval prior to issuance.

5.2.4    The letter of credit or any replacement letter of credit shall be irrevocable for the term thereof and shall automatically renew on a year to year basis until a period ending not earlier than 45 days after the Termination Date (“End Date”) without any action whatsoever on the part of Landlord; provided that the issuing bank shall have the right not to renew the letter of credit by giving written notice to Landlord not less than sixty (60) days prior to the expiration of the then current term of the letter of credit that it does not intend to renew the letter of credit. Tenant understands that the election by the issuing bank not to renew the letter of credit shall not, in any event, diminish the obligation of Tenant to maintain such an irrevocable letter of credit in favor of Landlord through such date.

5.2.5    Landlord, or its then managing agent, shall have the right from time to time to make one or more draws on the letter of credit at any time that Landlord has the right to use all or a part of the Security Deposit pursuant to Article 5 of this Lease, and the proceeds may be applied as permitted under said Article 5. The letter of credit must state that it can be presented for payment at the office of the issuer or an approved correspondent in the metropolitan area in which the Building is located. Funds may be drawn down on the letter of credit upon presentation to the issuing or corresponding bank of Landlord’s (or Landlord’s then managing agent’s) certificate stating as follows:

“Beneficiary is entitled to draw on this credit pursuant to that certain Lease dated for reference                      between 321 SUMMER STREET LLC, a Delaware limited liability company, as Landlord and                     , a                     , as Tenant, as amended from time to time.”

It is understood that if Landlord or its managing agent be a corporation, partnership or other entity, then such statement shall be signed by an officer (if a corporation), a general partner (if a partnership), or any authorized party (if another entity).

5.2.6    Tenant acknowledges and agrees (and the letter of credit shall so state) that the letter of credit shall be honored by the issuing bank without inquiry as to the truth of the statements set forth in such draw request and regardless of whether the Tenant disputes the content of such statement.

5.2.7    In the event of a transfer of Landlord’s interest in the Premises, Landlord shall have the right to transfer the letter of credit to the transferee and Tenant shall take whatever action and pay any bank fees necessary to effectuate such transfer and thereupon the Landlord shall, without any further agreement between the parties, be released by Tenant from all liability therefor, and it is agreed that the provisions hereof shall apply to every transfer or assignment of said letter of credit to a new landlord.

5.2.8    Without limiting the generality of the foregoing, if the letter of credit expires earlier than the End Date, or the issuing bank notifies Landlord that it will not renew the letter of credit, Landlord shall accept a renewal thereof or substitute letter credit (such renewal or substitute letter of credit to be in effect not later than thirty (30) days prior to the expiration of the expiring letter of credit), irrevocable and automatically renewable as above provided to the End Date upon the same terms as the expiring letter of credit or upon such other terms as may be acceptable to Landlord. However, if (i) the letter of credit is not timely renewed, or (ii) a substitute letter of credit, complying with all of the terms and conditions of this Section is not timely received, then Landlord may present the expiring letter of

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credit to the issuing bank, and the entire sum so obtained shall be paid to Landlord, to be held by Landlord in accordance with Article 5 of the Lease. Notwithstanding the foregoing, Landlord shall be entitled to receive from Tenant a fee in an amount not to exceed $500.00 for attorneys’ fees incurred in connection with the review of any proposed substitute letter of credit pursuant to this subparagraph.

5.2.9    Provided that (i) no uncured monetary default exists as of the date that is twenty-four (24) full calendar months after the Rent Commencement Date (the “Reduction Date”), and (ii) in the twelve (12) month period preceding the Reduction Date not more than one (1) monetary default has occurred, whether or not cured, then, as of the Reduction Date, Landlord shall permit the amount of the letter of credit to be reduced to (or a replacement letter of credit may be issued in the amount of) $86,406.50. If Tenant is unable to satisfy any of the foregoing conditions as of the Reduction Date (whether the initial or any amended Reduction Date), then (i) the Reduction Date shall be amended to be twelve (12) months after the then current Reduction Date, and (ii) the reference to 24 full calendar months after the Rent Commencement Date shall be deemed to refer to the 24 full calendar months prior to the Reduction Date, provided in all events such amendment of the Reduction Date and the reduction of the amount of the letter of credit shall be a one-time reduction.

6.    ALTERATIONS.

6.1    Except for those, if any, specifically provided for in Exhibit B to this Lease, Tenant shall not make or suffer to be made any alterations, additions, or improvements, including, but not limited to, the attachment of any fixtures or equipment in, on, or to the Premises or any part thereof or the making of any improvements as required by Article 7, without the prior written consent of Landlord. When applying for such consent, Tenant shall, if requested by Landlord, furnish complete plans and specifications for such alterations, additions and improvements. Landlord’s consent shall not be unreasonably withheld, conditioned or delayed and Tenant shall not be required to furnish complete plans and specifications with respect to alterations which (i) are not structural in nature, (ii) are not visible from the exterior of the Building, (iii) do not affect or require modification of the Building’s electrical, mechanical, plumbing, HVAC or other systems, and (iv) in aggregate do not cost more than $7.00 per rentable square foot of that portion of the Premises affected by the alterations in question.

6.2    In the event Landlord consents to the making of any such alteration, addition or improvement by Tenant, the same shall be made by using either Landlord’s contractor or a contractor reasonably approved by Landlord, in either event at Tenant’s sole cost and expense. If Tenant shall employ any contractor other than Landlord’s contractor and such other contractor or any subcontractor of such other contractor shall employ any non-union labor or supplier, Tenant shall be responsible for and hold Landlord harmless from any and all delays, damages and extra costs suffered by Landlord as a result of any dispute with any labor unions concerning the wage, hours, terms or conditions of the employment of any such labor. In any event, for any work that involves mechanical, electrical, plumbing or sprinkler trades, Landlord may charge Tenant a construction management fee not to exceed two and one-half percent (2.5%) of the cost of any such work that involves material alterations to cover its overhead as it relates to such proposed work, plus third-party costs actually incurred by Landlord in connection with the proposed work and the design thereof, with all such amounts being due ten (10) business days after Landlord’s demand.

6.3    All alterations, additions or improvements proposed by Tenant shall be constructed in accordance with all Regulations and with Landlord’s Building construction standards (if any) from time to time to the extent applicable (which standards shall be made available to Tenant by Landlord’s Building manager upon request). Tenant shall use Building standard materials where applicable, and Tenant shall,

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prior to construction, provide the additional insurance required under Article 11 in such case, and also all such assurances to Landlord as Landlord shall reasonably require to assure payment of the costs thereof, including but not limited to, notices of non-responsibility, waivers of lien, surety company performance bonds and funded construction escrows and to protect Landlord and the Building and appurtenant land against any loss from any mechanic’s, materialmen’s or other liens. Tenant shall pay in addition to any sums due pursuant to Article 4, any increase in real estate taxes attributable to any such alteration, addition or improvement for so long, during the Term, as such increase is ascertainable; at Landlord’s election said sums shall be paid in the same way as sums due under Article 4. Landlord may, as a condition to its consent to any particular alterations or improvements, require Tenant to deposit with Landlord the amount reasonably estimated by Landlord as sufficient to cover the cost of removing such alterations or improvements and restoring the Premises, to the extent required under Section 26.2.

7.    REPAIR.

7.1    Landlord shall have no obligation to alter, remodel, improve, repair, decorate or paint the Premises, except as specified in Exhibit B attached to this Lease and except that Landlord shall repair and maintain the structural portions of the Building, including the basic plumbing, air conditioning, heating and electrical systems installed or furnished by Landlord. By taking possession of the Premises, Tenant accepts them as being in good order, condition and repair and in the condition in which Landlord is obligated to deliver them, except for latent defects or as set forth in the punch list to be delivered pursuant to Section 2.1. It is hereby understood and agreed that no representations respecting the condition of the Premises or the Building have been made by Landlord to Tenant, except as specifically set forth in this Lease.

7.2    Tenant shall, at all times during the Term, keep the Premises in good condition and repair excepting damage by fire, or other casualty, and in compliance with all Regulations promptly complying with all governmental orders and directives for the correction, prevention and abatement of any violations or nuisances in or upon, or connected with, the Premises, all at Tenant’s sole expense. Repair and maintenance work shall be undertaken in compliance with Landlord’s Building construction standards (if any) from time to time to the extent applicable (which standards shall be made available to Tenant by Landlord’s Building manager upon request).

7.3    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 written notice of the need of such repairs or maintenance is given to Landlord by Tenant; provided however, if Landlord fails to make any repairs that materially impair Tenant’s ability to make full use of the Premises within twenty-five (25) days after written notice of the need for such repairs is given to Landlord by Tenant and it is within Landlord’s control to make such repairs, Tenant shall be entitled to an abatement of Annual Rent until such repairs are completed by Landlord in proportion to the extent that Tenant’s ability to use the Premises is materially impaired.

7.4    Except as provided in Section 7.3 or Article 22, there shall be no abatement of rent and no liability of Landlord by reason of any injury to or interference with Tenant’s business arising from the making of any repairs, alterations or improvements in or to any portion of the Building or the Premises or to fixtures, appurtenances and equipment in the Building. Except to the extent, if any, prohibited by law, Tenant waives the right to make repairs at Landlord’s expense under any law, statute or ordinance now or hereafter in effect.

8.    LIENS. Tenant shall keep the Premises, the Building and appurtenant land and Tenant’s leasehold interest in the Premises free from any liens arising out of any services, work or materials

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performed, furnished, or contracted for by Tenant, or obligations incurred by Tenant. In the event that Tenant fails, within ten (10) days following the imposition of any such lien, to either cause the same to be released of record or provide Landlord with insurance against the same issued by a major title insurance company or such other protection against the same as Landlord shall accept (such failure to constitute an Event of Default), Landlord shall have the right to cause the same to be released by such means as it shall deem proper, including payment of the claim giving rise to such lien. All such sums paid by Landlord and all expenses incurred by it in connection therewith shall be payable to it by Tenant within five (5) days of Landlord’s demand .

9.    ASSIGNMENT AND SUBLETTING.

9.1    Except as otherwise provided by this Section 9, Tenant shall not have the right to assign or pledge this Lease or to sublet the whole or any part of the Premises whether voluntarily or by operation of law, or permit the use or occupancy of the Premises by anyone other than Tenant, and shall not make, suffer or permit such assignment, subleasing or occupancy without the prior written consent of Landlord, such consent not to be unreasonably withheld, conditioned or delayed and said restrictions shall be binding upon any and all assignees of this Lease and subtenants of the Premises. In the event Tenant desires to sublet, or permit such occupancy of, the Premises, or any portion thereof, or assign this Lease, Tenant shall give written notice thereof to Landlord at least twenty (20) days but no more than forty-five (45) days prior to the proposed commencement date of such subletting or assignment, which notice shall set forth the name of the proposed subtenant or assignee, the relevant terms of any sublease or assignment and copies of financial reports and other relevant financial information of the proposed subtenant or assignee reasonably requested by Landlord.

9.2    Notwithstanding any assignment or subletting, permitted or otherwise, Tenant shall at all times remain directly, primarily and fully responsible and liable for the payment of the rent specified in this Lease and for compliance with all of its other obligations under the terms, provisions and covenants of this Lease. Upon the occurrence of an Event of Default, if the Premises or any part of them are then assigned or sublet, Landlord, in addition to any other remedies provided in this Lease or provided by law, may, at its option, collect directly from such assignee or subtenant all rents due and becoming due to Tenant under such assignment or sublease and apply such rent against any sums due to Landlord from Tenant under this Lease, and no such collection shall be construed to constitute a novation or release of Tenant from the further performance of Tenant’s obligations under this Lease.

9.3    In addition to Landlord’s right to approve of any subtenant or assignee, Landlord shall have the option, in its sole discretion, in the event of any proposed subletting of more than twenty-five percent (25%) of the Premises for the remainder of the Term or assignment, to terminate this Lease, or in the case of a proposed subletting of less than the entire Premises (but more than twenty-five percent (25%) of the Premises for the remainder of the Term), to recapture the portion of the Premises to be sublet, as of the date the subletting or assignment is to be effective. The option shall be exercised, if at all, by Landlord giving Tenant written notice given by Landlord to Tenant within twenty (20) days following Landlord’s receipt of Tenant’s written notice as required above. However, if Tenant notifies Landlord, within five (5) days after receipt of Landlord’s termination notice, that Tenant is rescinding its proposed assignment or sublease, the termination notice shall be void and this Lease shall continue in full force and effect. If this Lease shall be terminated with respect to the entire Premises pursuant to this Section, the Term of this Lease shall end on the date stated in Tenant’s notice as the effective date of the sublease or assignment as if that date had been originally fixed in this Lease for the expiration of the Term. If Landlord recaptures under this Section only a portion of the Premises, the rent to be paid from time to time during the unexpired Term shall abate proportionately based on the proportion by which the approximate square footage of the

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remaining portion of the Premises shall be less than that of the Premises as of the date immediately prior to such recapture. Tenant shall, at Tenant’s own cost and expense, discharge in full any outstanding commission obligation which may be due and owing as a result of any proposed assignment or subletting, whether or not the Premises are recaptured pursuant to this Section 9.3 and rented by Landlord to the proposed tenant or any other tenant.

9.4    In the event that Tenant sells, sublets, assigns or transfers this Lease, Tenant shall pay to Landlord as additional rent an amount equal to fifty percent (50%) of any Increased Rent (as defined below), less the Costs Component (as defined below), when and as such Increased Rent is received by Tenant. As used in this Section, “Increased Rent” shall mean the excess of (i) all rent and other consideration which Tenant is entitled to receive by reason of any sale, sublease, assignment or other transfer of this Lease, over (ii) the rent otherwise payable by Tenant under this Lease at such time. For purposes of the foregoing, any consideration received by Tenant in form other than cash shall be valued at its fair market value as determined by Landlord in good faith. The “Costs Component” is that amount which, if paid monthly, would fully amortize on a straight-line basis, over the entire period for which Tenant is to receive Increased Rent, the actual costs incurred by Tenant for leasing commissions, legal fees and tenant improvements in connection with such sublease, assignment or other transfer.

9.5    Notwithstanding any other provision hereof, it shall be considered reasonable for Landlord to withhold its consent to any assignment of this Lease or sublease of any portion of the Premises if at the time of either Tenant’s notice of the proposed assignment or sublease or the proposed commencement date thereof, there shall exist any uncured default of Tenant or matter which will become a default of Tenant with passage of time unless cured, or if the proposed assignee or sublessee is an entity: (a) with which Landlord is already in active negotiation (trading proposals within the last 6 months); (b) is already an occupant of the Building unless Landlord is unable to provide the amount of space required by such occupant; (c) is a governmental agency; (d) is incompatible with the character of occupancy of the Building as determined by Landlord in its reasonable discretion; (e) with which the payment for the sublease or assignment is determined in whole or in part based upon its net income or profits; or (f) would subject the Premises to a use which would: (i) involve increased wear upon the Building; (ii) violate any exclusive right granted to another tenant of the Building; (iii) require any addition to or modification of the Premises or the Building in order to comply with building code or other governmental requirements; or, (iv) involve a violation of Section 1.2; or (v) shall, in Landlord’s reasonable opinion, cause the Building or any part thereof to be in material non-compliance with Landlord’s sustainability practices and/or the “green building” certification or rating obtained, or in the process of being obtained by Landlord for the Building. Tenant expressly agrees that for the purposes of any statutory or other requirement of reasonableness on the part of Landlord, Landlord’s refusal to consent to any assignment or sublease for any of the reasons described in this Section 9.5, shall be conclusively deemed to be reasonable.

9.6    Upon any request to assign or sublet, Tenant will pay to Landlord the Assignment/Subletting Fee plus, on demand, a sum equal to all of Landlord’s costs, including reasonable and actual attorney’s fees, incurred in investigating and considering any proposed or purported assignment or pledge of this Lease or sublease of any of the Premises, regardless of whether Landlord shall consent to, refuse consent, or determine that Landlord’s consent is not required for, such assignment, pledge or sublease, which total sum (including the Assignment/Subletting Fee) shall not exceed $5,000. Any purported sale, assignment, mortgage, transfer of this Lease or subletting which does not comply with the provisions of this Article 9 shall be void.

9.7    If Tenant is a corporation, limited liability company, partnership or trust, any transfer or transfers of or change or changes within any twelve (12) month period in the number of the outstanding

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voting shares of the corporation or limited liability company, the general partnership interests in the partnership or the identity of the persons or entities controlling the activities of such partnership or trust resulting in the persons or entities owning or controlling a majority of such shares, partnership interests or activities of such partnership or trust at the beginning of such period no longer having such ownership or control shall be regarded as equivalent to an assignment of this Lease to the persons or entities acquiring such ownership or control and shall be subject to all the provisions of this Article 9 to the same extent and for all intents and purposes as though such an assignment; provided however, the sale or transfer of a controlling interest of Tenant’s capital stock in a transaction or series of related transaction the intent of which is to finance Tenant’s ongoing business and operations and the acquirer(s) of which are professional investors who typically invest in companies of the same type and kind as Tenant shall not be deemed an assignment or sublease hereunder.

9.8    Notwithstanding anything herein to the contrary, Tenant may, without the requirement of obtaining Landlord’s consent, assign this Lease or sublease any portion of the Premises to any entity which controls, is controlled by or under common control with Tenant (an “Affiliate”) or assign this Lease to any entity with which Tenant may merge or consolidate or to which Tenant may sell all or substantially all of its assets or equity interests (each, a “Transfer”), provided that all of the following conditions are satisfied: (a) there must not be an uncured Event of Default at the time of the Transfer; (b) the successor entity (or Tenant if Tenant is the surviving entity) shall have a net worth following the Transfer that is equal to or better than the net worth of Tenant during the 12 months immediately prior to the Transfer; and (c) Tenant must give Landlord written notice at least ten (10) business days before such Transfer; provided, however, that if the Transfer is subject to a nondisclosure or confidentiality agreement, then Tenant will notify Landlord within five (5) business days following the Transfer. A Transfer that satisfies all of such conditions is a “Permitted Transfer.” Tenant’s notice to Landlord shall include information and documentation reasonably evidencing that the Transfer qualifies as a Permitted Transfer hereunder and that each of the above conditions has been satisfied. If requested by Landlord, Tenant’s successor shall sign and deliver to Landlord a commercially reasonable form of assumption agreement.. Any right of Landlord to terminate this Lease or recapture the Premises, as set forth in Section 9.3, or receive any amounts set forth in Section 9.5 hereunder shall not apply to a Permitted Transfer.

10.    INDEMNIFICATION. None of the Landlord Entities shall be liable and Tenant hereby waives all claims against them for any damage to any property or any injury to any person in or about the Premises or the Building by or from any cause whatsoever (including without limiting the foregoing, rain or water leakage of any character from the roof, windows, walls, basement, pipes, plumbing works or appliances, the Building not being in good condition or repair, gas, fire, oil, electricity or theft), except to the extent prohibited by law or caused by or arising from the gross negligence or willful misconduct of Landlord or its agents, employees or contractors. Tenant shall protect, indemnify and hold the Landlord Entities harmless from and against any and all loss, claims, liability or costs (including court costs and attorney’s fees) incurred by reason of (a) any damage to any property (including but not limited to property of any Landlord Entity) or any injury (including but not limited to death) to any person occurring in, on or about the Premises or the Building to the extent that such injury or damage shall be caused by or arise from any actual or alleged act, neglect, fault, or omission by or of Tenant or any Tenant Entity to meet any standards imposed by any duty with respect to the injury or damage; (b) the conduct or management of any work or thing whatsoever done by the Tenant in or about the Premises or from transactions of the Tenant concerning the Premises; (c) Tenant’s actual or asserted failure to comply with any and all Regulations applicable to the condition or use of the Premises or its occupancy; or (d) any breach or default on the part of Tenant in the performance of any covenant or agreement on the part of the Tenant to be performed pursuant to this Lease. The provisions of this Article shall survive the termination of this Lease with respect to any claims or liability accruing prior to such termination.

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11.    INSURANCE.

11.1    Tenant shall keep in force throughout the Term: (a) a Commercial General Liability insurance policy or policies to protect the Landlord Entities against any liability to the public or to any invitee of Tenant or a Landlord Entity incidental to the use of or resulting from any accident occurring in or upon the Premises with a limit of not less than $1,000,000.00 per occurrence and not less than $2,000,000.00 in the annual aggregate, or such larger amount as Landlord may prudently require from time to time, covering bodily injury and property damage liability and $1,000,000 products/completed operations aggregate; (b) Business Auto Liability covering owned, non-owned and hired vehicles with a limit of not less than $1,000,000 per accident; (c) Worker’s Compensation Insurance with limits as required by statute and Employers Liability with limits of $500,000 each accident, $500,000 disease policy limit, $500,000 disease—each employee; (d) All Risk or Special Form coverage protecting Tenant against loss of or damage to Tenant’s alterations, additions, improvements, carpeting, floor coverings, panelings, decorations, fixtures, inventory and other business personal property situated in or about the Premises to the full replacement value of the property so insured; and, (e) Business Interruption Insurance with limit of liability representing loss of at least approximately six (6) months of income.

11.2    The aforesaid policies shall (a) be provided at Tenant’s expense; (b) name the Landlord Entities as additional insureds (General Liability) and loss payee (Property—Special Form); (c) be issued by an insurance company with a minimum Best’s rating of “A-:VII” during the Term; and (d) provide that said insurance shall not be canceled unless thirty (30) days prior written notice (ten days for non-payment of premium) shall have been given to Landlord; a certificate of Liability insurance on ACORD Form 25 and a certificate of Property insurance on ACORD Form 28 shall be delivered to Landlord by Tenant upon the Commencement Date and at least thirty (30) days prior to each renewal of said insurance.

11.3    Whenever Tenant shall undertake any alterations, additions or improvements in, to or about the Premises (“Work”) the aforesaid insurance protection must extend to and include injuries to persons and damage to property arising in connection with such Work, without limitation including liability under any applicable structural work act, and such other insurance as Landlord shall require; and the policies of or certificates evidencing such insurance must be delivered to Landlord prior to the commencement of any such Work.

12.    WAIVER OF SUBROGATION. Tenant and Landlord hereby mutually waive their respective rights of recovery against each other for any loss insured (or required to be insured pursuant to this Lease) by fire, extended coverage, All Risks or other insurance now or hereafter existing for the benefit of the respective party but only to the extent of the net insurance proceeds payable under such policies. Each party shall obtain any special endorsements required by their insurer to evidence compliance with the aforementioned waiver.

13.    SERVICES AND UTILITIES.

13.1    Subject to the other provisions of this Lease, Landlord agrees to furnish to the Premises during Building Business Hours (specified on the Reference Pages) on generally recognized business days (but exclusive in any event of Sundays and national and local legal holidays), the following services and utilities subject to the rules and regulations of the Building prescribed from time to time: (a) water suitable for normal office use of the Premises; (b) heat and air ’for the use and occupation of the Premises during Building Business Hours at levels commensurate with other Class A office buildings in Boston, MA; (c) cleaning and janitorial service commensurate with other Class A office buildings in Boston, MA; (d) elevator service by non-attended automatic elevators, if applicable; and, (e) equipment to bring to the

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Premises electricity for lighting, convenience outlets and other normal office use. Landlord, at Landlord’s cost and expense, may install and shall have access to the Premises to monitor a separate meter (or submeter) to determine the actual use of any utility in the Premises or any shared common area and may make available and share actual whole-project energy and water usage data as necessary to maintain the Building’s “green building” certification. If Tenant pays for utilities directly to the utility company(ies), then, upon request and at no cost to Tenant, Tenant shall provide monthly utility usage to Landlord in electronic or paper format or provide permission for Landlord to request information regarding Tenant’s utility usage directly from the utility company. To the extent that Tenant is not billed directly by a public utility, Tenant shall pay, within thirty (30) days of Landlord’s demand, for all electricity used by Tenant in the Premises as determined by submeters serving the Premises. The charge shall be at the rates charged for such services by the local public utility. In the absence of Landlord’s gross negligence or willful misconduct, Landlord shall not be liable for, and Tenant shall not be entitled to, any abatement or reduction of rental by reason of Landlord’s failure to furnish any of the foregoing, unless such failure shall persist for ten (10) days or more after written notice of such failure is given to Landlord by Tenant and provided further that Landlord shall not be liable when such failure is caused by accident, breakage, repairs, labor disputes of any character, energy usage restrictions or by any other cause, similar or dissimilar, beyond the reasonable control of Landlord. Landlord shall use reasonable efforts to remedy any interruption in the furnishing of services and utilities.

With respect to electricity, there is one meter serving the entire fourth (4^th) floor and Tenant shall pay 81.79% (i.e., 8,499/10,368) (“Tenant’s Electrical Share”) of the costs of the electrical consumption for the fourth (4^th) floor. Any submetering configuration that may be rendered necessary due to Tenant’s alterations to the Premises shall be performed by Tenant at Tenant’s expense. If at any time during the Term the electrical submeter for the Premises is not operational, then Landlord may charge Tenant for Tenant’s estimated electricity usage in the Premises at Landlord’s then standard electrical rate (which is currently $2.00 per RSF per year). Landlord shall not be liable in any way to Tenant for any failure or defect in the supply or character of electrical energy furnished to the Premises by reason of any requirement, act or omission of the public utility serving the Building with electricity unless due to the act or omission of Landlord. Tenant’s use of electrical energy in the Premises shall not at any time exceed the capacity of any of the electrical conductors and equipment in or otherwise serving the Premises. In order to ensure that such capacity is not exceeded and to avert possible adverse effect upon the Building electrical services, Tenant shall give notice to Landlord and obtain Landlord’s prior written consent whenever Tenant shall connect to the Building electrical distribution system any major fixtures, appliances or equipment, except for standard office equipment, such as computers, copiers, printers, and server equipment. Any additional feeders or risers to supply Tenant’s electrical requirements in addition to those originally installed and all other equipment proper and necessary in connection with such feeders or risers, shall be installed by Landlord upon Tenant’s request, at the sole cost and expense of Tenant, provided that such additional feeders and risers are permissible under applicable laws and insurance regulations and the installation of such feeders or risers will not cause permanent damage or injury to the Building or cause or create a dangerous condition or unreasonably interfere with other tenants of the Building. Tenant agrees that it will not make any significant alteration or material addition to the electrical equipment and/or appliances in the Premises without the prior written consent of Landlord in each instance first obtained, which consent will not be unreasonably withheld or delayed, and will promptly advise Landlord of any alteration or addition to such electrical equipment and/or appliances. Tenant, at Tenant’s expense, shall purchase, install and replace all light fixtures, bulbs, tubes, lamps, lenses, globes, ballasts and switches used in the Premises.

13.2    Should Tenant require any additional work or service, as described above, including services furnished outside ordinary business hours specified above, Landlord may, on terms to be agreed,

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upon reasonable advance notice by Tenant, furnish such additional service and Tenant agrees to pay Landlord such charges as may be agreed upon, including any tax imposed thereon, but in no event at a charge less than Landlord’s actual cost plus overhead for such additional service and, where appropriate, a reasonable allowance for depreciation of any systems being used to provide such service. The current charge for after-hours HVAC service, which is subject to change at any time, is specified on the Reference Pages.

13.3    Wherever heat-generating machines or equipment are used by Tenant in the Premises which affect the temperature otherwise maintained by the air conditioning system or Tenant allows occupancy of the Premises by more persons than the heating and air conditioning system is designed to accommodate, in either event whether with or without Landlord’s approval, Landlord reserves the right to install supplementary heating and/or air conditioning units in or for the benefit of the Premises and the cost thereof, including the cost of installation and the cost of operations and maintenance, shall be paid by Tenant to Landlord within five (5) days of Landlord’s demand. In addition, if applicable, Landlord may install at its sole expense and shall have access to the Premises to monitor a separate meter (or submeter) to determine the actual use of any utility in the Premises or any shared common area and may make available and share actual whole-project energy and water usage data as necessary to maintain the Building’s “green building” certification, if any. If there is no meter or submeter in the Premises or if Tenant is billed directly by a public utility, then, upon request, Tenant shall provide monthly utility usage to Landlord in electronic or paper format or provide permission for Landlord to request information regarding Tenant’s utility usage directly from the utility company.

13.4    Tenant will not, without the written consent of Landlord, use any apparatus or device in the Premises, including but not limited to, electronic data processing machines and machines using current in excess of 2000 watts and/or 20 amps or 120 volts, which will in any way increase the amount of electricity or water usually furnished or supplied for use of the Premises for normal office use, nor connect with electric current, except through existing electrical outlets in the Premises, or water pipes, any apparatus or device for the purposes of using electrical current or water. If Tenant shall require water or electric current in excess of that usually furnished or supplied for use of the Premises as normal office use, Tenant shall procure the prior written consent of Landlord for the use thereof, which Landlord may refuse, and if Landlord does consent, Landlord may cause a water meter or electric current meter to be installed so as to measure the amount of such excess water and electric current. The cost of any such meters shall be paid for by Tenant. Tenant agrees to pay to Landlord within five (5) days of Landlord’s demand , the cost of all such excess water and electric current consumed (as shown by said meters, if any, or, if none, as reasonably estimated by Landlord) at the rates charged for such services by the local public utility or agency, as the case may be, furnishing the same, plus any additional expense incurred in keeping account of the water and electric current so consumed.

13.5    Tenant will not, without the written consent of Landlord, contract with a utility provider to service the Premises with any utility, including, but not limited to, telecommunications, electricity, water, sewer or gas, which is not previously providing such service to other tenants in the Building. Subject to Landlord’s reasonable rules and regulations and the provisions of Articles 6 and 26, Tenant shall be entitled to the use of wiring (“Communications Wiring”) from the existing telecommunications nexus in the Building to the Premises, sufficient for normal general office use of the Premises. Tenant shall not install any additional Communications Wiring, nor remove any Communications Wiring, without in each instance obtaining the prior written consent of Landlord, which consent may be withheld in Landlord’s sole and absolute discretion. Landlord’s shall in no event be liable for disruption in any service obtained by Tenant pursuant to this paragraph.

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13.6    Tenant covenants and agrees to (a) comply with applicable law regarding the collection, sorting, separation, and recycling of garbage, waste products, trash and other refuse at the Building (collectively, “trash”) and (b) to sort and separate its trash into separate recycling containers as required by law, or furnished by Landlord and located in the Premises pursuant to Landlord’s recycling policy for the Building. Landlord reserves the right to refuse to collect or accept from Tenant any trash that is not separated and sorted as required by law or pursuant to Landlord’s recycling policy, and to require Tenant to arrange for such collection at Tenant’s cost, utilizing a contractor reasonably satisfactory to Landlord. Tenant shall pay all costs, expenses, fines, penalties or damages that may be imposed on Landlord or Tenant by reason of Tenant’s failure to comply with the provisions of this paragraph.

14.    HOLDING OVER. Tenant shall pay Landlord for each day Tenant retains possession of the Premises or part of them after termination of this Lease by lapse of time or otherwise at the rate (“Holdover Rate”) which shall be One Hundred Fifty Percent (150%) of the amount of the Annual Rent for the last period prior to the date of such termination plus Tenant’s Proportionate Share of Expenses, Insurance Costs and Taxes under Article 4, prorated on a daily basis, and if such holdover lasts for more than 15 days, also pay all damages sustained by Landlord by reason of such retention. Any such holdover shall create ’a tenancy at sufferance at the Holdover Rate. In any event, no provision of this Article 14 shall be deemed to waive Landlord’s right of reentry or any other right under this Lease or at law.

15.    SUBORDINATION. Without the necessity of any additional document being executed by Tenant for the purpose of effecting a subordination, this Lease shall be subject and subordinate at all times to ground or underlying leases and to the lien of any mortgages or deeds of trust now or hereafter placed on, against or affecting the Building, Landlord’s interest or estate in the Building, or any ground or underlying lease; provided, however, that if the lessor, mortgagee, trustee, or holder of any such mortgage or deed of trust elects to have Tenant’s interest in this Lease be superior to any such instrument, then, by notice to Tenant, this Lease shall be deemed superior, whether this Lease was executed before or after said instrument. Notwithstanding the foregoing, Tenant covenants and agrees to execute and deliver within ten (10) days of Landlord’s request such further instruments evidencing such subordination or superiority of this Lease as may be required by Landlord.

16.    RULES AND REGULATIONS. Tenant shall faithfully observe and comply with all the rules and regulations as set forth in Exhibit D to this Lease and all reasonable and non-discriminatory modifications of and additions to them from time to time put into effect by Landlord. Landlord shall not be responsible to Tenant for the non-performance by any other tenant or occupant of the Building of any such rules and regulations.

17.    REENTRY BY LANDLORD.

17.1    Landlord reserves and shall, upon at least 24 hours prior written notice (except in cases of emergency or for regularly scheduled janitorial services), have the right to re-enter the Premises to inspect the same, to supply janitor service and any other service to be provided by Landlord to Tenant under this Lease, to show said Premises to prospective purchasers or mortgagees or, in the last 12 months of the term of the Lease, to prospective tenants, and to alter, improve or repair the Premises and any portion of the Building, without abatement of rent, and may for that purpose erect, use and maintain scaffolding, pipes, conduits and other necessary structures and open any wall, ceiling or floor in and through the Building and Premises where reasonably required by the character of the work to be performed, provided entrance to the Premises shall not be blocked thereby, and further provided that the business of Tenant shall not be interfered with unreasonably. Landlord shall have the right at any time to change the arrangement and/or locations of entrances, or passageways, doors and doorways, and corridors, windows, elevators, stairs,

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toilets or other public parts of the Building and to change the name, number or designation by which the Building is commonly known. In the event that Landlord damages any portion of any wall or wall covering, ceiling, or floor or floor covering within the Premises, Landlord shall repair or replace the damaged portion to match the original as nearly as commercially reasonable but shall not be required to repair or replace more than the portion actually damaged. Other than in cases of emergencies, Tenant shall have the right to have one of its personnel accompany Landlord’s personnel and invitees at all times during which they are on the Premises. Tenant hereby waives any claim for damages for any injury or inconvenience to or interference with Tenant’s business, any loss of occupancy or quiet enjoyment of the Premises, and any other loss occasioned by any action of Landlord authorized by this Article 17, except to the extent caused by Landlord’s gross negligence or willful misconduct.

17.2    For each of the aforesaid purposes, Landlord shall at all times have and retain a key with which to unlock all of the doors in the Premises, excluding Tenant’s vaults and safes or special security areas (designated in advance), and Landlord shall have the right to use any and all means which Landlord may deem proper to open said doors in an emergency to obtain entry to any portion of the Premises. As to any portion to which access cannot be had by means of a key or keys in Landlord’s possession, in cases of emergency only, Landlord is authorized to gain access by such means as Landlord shall elect and the cost of repairing any damage occurring in doing so shall be borne by Tenant and paid to Landlord within five (5) business days of Landlord’s demand.

18.    DEFAULT.

18.1    Except as otherwise provided in Article 20, the following events shall be deemed to be “Events of Default” under this Lease:

18.1.1    Tenant shall fail to pay when due any sum of money becoming due to be paid to Landlord under this Lease, whether such sum be any installment of the rent reserved by this Lease, any other amount treated as additional rent under this Lease, or any other payment or reimbursement to Landlord required by this Lease, whether or not treated as additional rent under this Lease, and such failure shall continue for a period of (5) business days after written notice that such payment was not made when due, but if any such notice shall be given two times, for the twelve (12) month period commencing with the date of such notice, the failure to pay within five business days after due any additional sum of money becoming due to be paid to Landlord under this Lease during such period shall be an Event of Default, without notice.

18.1.2    Tenant shall fail to comply with any term, provision or covenant of this Lease which is not provided for in another Section of this Article and shall not cure such failure within thirty (30) days (forthwith, if the failure involves a hazardous condition) after written notice of such failure to Tenant; provided, however, that such failure shall not be an Event of Default if such failure could not reasonably be cured during such twenty (20) day period, Tenant has commenced the cure within such twenty (20) day period and thereafter is diligently pursuing such cure to completion, but the total aggregate cure period shall not exceed ninety (90) days.

18.1.3    Tenant shall fail to vacate the Premises immediately upon termination of this Lease, by lapse of time or otherwise, or upon termination of Tenant’s right to possession only.

18.1.4    Tenant shall become insolvent, admit in writing its inability to pay its debts generally as they become due, file a petition in bankruptcy or a petition to take advantage of any insolvency statute, make an assignment for the benefit of creditors, make a transfer in fraud of creditors,

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apply for or consent to the appointment of a receiver of itself or of the whole or any substantial part of its property, or file a petition or answer seeking reorganization or arrangement under the federal bankruptcy laws, as now in effect or hereafter amended, or any other applicable law or statute of the United States or any state thereof.

18.1.5    A court of competent jurisdiction shall enter an order, judgment or decree adjudicating Tenant bankrupt, or appointing a receiver of Tenant, or of the whole or any substantial part of its property, without the consent of Tenant, or approving a petition filed against Tenant seeking reorganization or arrangement of Tenant under the bankruptcy laws of the United States, as now in effect or hereafter amended, or any state thereof, and such order, judgment or decree shall not be vacated or set aside or stayed within ninety (90) days from the date of entry thereof.

19.    REMEDIES.

19.1    Except as otherwise provided in Article 20, upon the occurrence of any of the Events of Default described or referred to in Article 18, Landlord shall have the option to pursue any one or more of the following remedies without any notice or demand whatsoever, concurrently or consecutively and not alternatively:

19.1.1    Landlord may, at its election, terminate this Lease or terminate Tenant’s right to possession only, without terminating the Lease.

19.1.2    Upon any termination of this Lease, whether by lapse of time or otherwise, or upon any termination of Tenant’s right to possession without termination of this Lease, Tenant shall surrender possession and vacate the Premises immediately, and deliver possession thereof to Landlord, and Tenant hereby grants to Landlord full and free license to enter into and upon the Premises in such event and to repossess Landlord of the Premises as of Landlord’s former estate and to expel or remove Tenant and any others who may be occupying or be within the Premises and to remove Tenant’s signs and other evidence of tenancy and all other property of Tenant therefrom without being deemed in any manner guilty of trespass, eviction or forcible entry or detainer, and without incurring any liability for any damage resulting therefrom, Tenant waiving any right to claim damages for such re-entry and expulsion, and without relinquishing Landlord’s right to rent or any other right given to Landlord under this Lease or by operation of law.

19.1.3    Upon any termination of this Lease, whether by lapse of time or otherwise, Landlord shall be entitled to recover as damages, all rent, including any amounts treated as additional rent under this Lease, and other sums due and payable by Tenant as of the date of termination, plus as liquidated damages and not as a penalty, an amount equal to the sum of: (a) an amount equal to the then present value of the rent reserved in this Lease for the residue of the stated Term of this Lease including any amounts treated as additional rent under this Lease and all other sums provided in this Lease to be paid by Tenant, minus the fair rental value of the Premises for such residue; and (b) the estimated expenses described in Section 19.1.4 relating to recovery of the Premises and for reletting itself and (c) the cost of performing any other covenants which would have otherwise been performed by Tenant.

19.1.4    Upon any termination of Tenant’s right to possession only without termination of this Lease:

19.1.4.1     Neither such termination of Tenant’s right to possession nor Landlord’s taking and holding possession thereof as provided in Section 19.1.2 shall terminate this Lease

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or release Tenant, in whole or in part, from any obligation, including Tenant’s obligation to pay the rent, including any amounts treated as additional rent, under this Lease for the full Term, and if Landlord so elects Tenant shall continue to pay to Landlord the entire amount of the rent as and when it becomes due, including any amounts treated as additional rent under this Lease, for the remainder of the Term plus any other sums provided in this Lease to be paid by Tenant for the remainder of the Term. For the avoidance of doubt, if Landlord elects to collect the lump sum damages from Tenant pursuant to Section 19.1.3, Tenant shall have no obligation to make payments to Landlord pursuant to this Section 19.1.4.

19.1.4.2     Landlord shall use commercially reasonable efforts to relet the Premises or portions thereof to the extent required by applicable law. Landlord and Tenant agree that nevertheless Landlord shall at most be required to use only the same efforts Landlord then uses to lease premises in the Building generally and that in any case that Landlord shall not be required to give any preference or priority to the showing or leasing of the Premises or portions thereof over any other space that Landlord may be leasing or have available and may place a suitable prospective tenant in any such other space regardless of when such other space becomes available and that Landlord shall have the right to relet the Premises for a greater or lesser term than that remaining under this Lease, the right to relet only a portion of the Premises, or a portion of the Premises or the entire Premises as a part of a larger area, and the right to change the character or use of the Premises. In connection with or in preparation for any reletting, Landlord may, but shall not be required to, make reasonable repairs, alterations and additions in or to the Premises and redecorate the same, and Tenant shall pay the cost thereof, together with Landlord’s expenses of reletting, including, without limitation, any commission incurred by Landlord, within twenty (20) days of Landlord’s demand. Landlord shall not be required to observe any instruction given by Tenant about any reletting or accept any tenant offered by Tenant unless such offered tenant has a credit-worthiness acceptable to Landlord and leases the entire Premises upon terms and conditions including a rate of rent (after giving effect to all expenditures by Landlord for tenant improvements, broker’s commissions and other leasing costs) all no less favorable to Landlord than as called for in this Lease, nor shall Landlord be required to make or permit any assignment or sublease for more than the current term or which Landlord would not be required to permit under the provisions of Article 9.

19.1.4.3     Until such time as Landlord shall elect to terminate this Lease and shall thereupon be entitled to recover the amounts specified in such case in Section 19.1.3, Tenant shall pay to Landlord upon demand the full amount of all rent, including any amounts treated as additional rent under this Lease and other sums reserved in this Lease for the remaining Term, together with the costs of reasonable repairs, alterations, additions, redecorating and Landlord’s expenses of reletting and the collection of the rent accruing therefrom (including reasonable attorney’s fees and broker’s commissions), as the same shall then be due or become due from time to time, less only such consideration as Landlord may have received from any reletting of the Premises; and Tenant agrees that Landlord may file suits from time to time to recover any sums falling due under this Article 19 as they become due. Any proceeds of reletting by Landlord in excess of the amount then owed by Tenant to Landlord from time to time shall be credited against Tenant’s future obligations under this Lease but shall not otherwise be refunded to Tenant or inure to Tenant’s benefit.

19.2    Upon the occurrence of an Event of Default, Landlord may (but shall not be obligated to) cure such default at Tenant’s sole expense. Without limiting the generality of the foregoing, Landlord may, at Landlord’s option, enter into and upon the Premises if Landlord determines in its sole discretion that Tenant is not acting within a commercially reasonable time to maintain, repair or replace anything for which Tenant is responsible under this Lease or to otherwise effect compliance with its obligations under this Lease and correct the same, without being deemed in any manner guilty of trespass, eviction or forcible

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entry and detainer and without incurring any liability for any damage or interruption of Tenant’s business resulting therefrom and Tenant agrees to reimburse Landlord within twenty (20) business days of Landlord’s demand as additional rent, for any expenses which Landlord may incur in thus effecting compliance with Tenant’s obligations under this Lease, plus interest from the date of expenditure by Landlord at the Wall Street Journal prime rate.

19.3    Tenant understands and agrees that in entering into this Lease, Landlord is relying upon receipt of all the Annual Rent, Monthly Installments of Rent and additional rent to become due with respect to all the Premises originally leased hereunder over the full Initial Term of this Lease for amortization, including interest at the Amortization Rate. For purposes hereof, the “Concession Amount” shall be defined as the aggregate of all amounts forgone or expended by Landlord as free rent under this Lease, under Exhibit B hereof for construction allowances (excluding therefrom any amounts expended by Landlord for the Landlord’s Work, as defined in Exhibit B), and for brokers’ commissions payable by reason of this Lease. Accordingly, Tenant agrees that if this Lease or Tenant’s right to possession of the Premises leased hereunder shall be terminated as of any date (“Default Termination Date”) prior to the expiration of the full Initial Term hereof by reason of a default of Tenant, there shall be due and owing to Landlord as of the day prior to the Default Termination Date, as rent in addition to all other amounts owed by Tenant as of such date, the amount (“Unamortized Amount”) of the Concession Amount determined as set forth below; provided, however, that in the event that such amounts are recovered by Landlord pursuant to any other provision of this Article 19, Landlord agrees that it shall not attempt to recover such amounts pursuant to this Section 19.3. For the purposes hereof, the Unamortized Amount shall be determined in the same manner as the remaining principal balance of a mortgage with interest at the Amortization Rate payable in level payments over the same length of time as from the effectuation of the Concession concerned to the end of the full Initial Term of this Lease would be determined.

19.4    If, on account of any breach or default by Tenant in Tenant’s obligations under the terms and conditions of this Lease, it shall become necessary or appropriate for Landlord to employ or consult with an attorney or collection agency concerning or to enforce or defend any of Landlord’s rights or remedies arising under this Lease or to collect any sums due from Tenant, Tenant agrees to pay all costs and fees so incurred by Landlord, including, without limitation, reasonable attorneys’ fees and costs. TENANT EXPRESSLY WAIVES ANY RIGHT TO: (A) TRIAL BY JURY; AND (B) SERVICE OF ANY NOTICE REQUIRED BY ANY PRESENT OR FUTURE LAW OR ORDINANCE APPLICABLE TO LANDLORDS OR TENANTS BUT NOT REQUIRED BY THE TERMS OF THIS LEASE.

19.5    Pursuit of any of the foregoing remedies shall not preclude pursuit of any of the other remedies provided in this Lease or any other remedies provided by law (all such remedies being cumulative), nor shall pursuit of any remedy provided in this Lease constitute a forfeiture or waiver of any rent due to Landlord under this Lease or of any damages accruing to Landlord by reason of the violation of any of the terms, provisions and covenants contained in this Lease. Notwithstanding the foregoing, once Landlord has elected to recover damages from Tenant under Section 19.1.3 and has, in fact, received such damages from Tenant, Landlord may not thereafter elect to receive damages under Section 19.1.4.

19.6    No act or thing done by Landlord or its agents during the Term shall be deemed a termination of this Lease or an acceptance of the surrender of the Premises, and no agreement to terminate this Lease or accept a surrender of said Premises shall be valid, unless in writing signed by Landlord. No waiver by Landlord of any violation or breach of any of the terms, provisions and covenants contained in this Lease shall be deemed or construed to constitute a waiver of any other violation or breach of any of the terms, provisions and covenants contained in this Lease. Landlord’s acceptance of the payment of rental or other payments after the occurrence of an Event of Default shall not be construed as a waiver of such Event

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of Default, unless Landlord so notifies Tenant in writing. Forbearance by Landlord in enforcing one or more of the remedies provided in this Lease upon an Event of Default shall not be deemed or construed to constitute a waiver of such Event of Default or of Landlord’s right to enforce any such remedies with respect to such Event of Default or any subsequent Event of Default.

19.7    To secure the payment of all rentals and other sums of money becoming due from Tenant under this Lease, Landlord shall have and Tenant grants to Landlord a first lien upon the leasehold interest of Tenant under this Lease, which lien may be enforced in equity.

19.8    Any and all property which may be removed from the Premises by Landlord pursuant to the authority of this Lease or of law, to which Tenant is or may be entitled, may be handled, removed and/or stored, as the case may be, by or at the direction of Landlord but at the risk, cost and expense of Tenant, and Landlord shall in no event be responsible for the value, preservation or safekeeping thereof. Tenant shall pay to Landlord, upon demand, any and all expenses incurred in such removal and all storage charges against such property so long as the same shall be in Landlord’s possession or under Landlord’s control. Any such property of Tenant not retaken by Tenant from storage within thirty (30) days after removal from the Premises shall, at Landlord’s option, be deemed conveyed by Tenant to Landlord under this Lease as by a bill of sale without further payment or credit by Landlord to Tenant.

19.9    If more than one (1) Event of Default occurs during the Term or any renewal thereof, Tenant’s renewal options, expansion options, purchase options and rights of first offer and/or refusal, if any are provided for in this Lease, shall be null and void.

20.    TENANT’S BANKRUPTCY OR INSOLVENCY.

20.1    If at any time and for so long as Tenant shall be subjected to the provisions of the United States Bankruptcy Code or other law of the United States or any state thereof for the protection of debtors as in effect at such time (each a “Debtor’s Law”):

20.1.1    Tenant, Tenant as debtor-in-possession, and any trustee or receiver of Tenant’s assets (each a “Tenant’s Representative”) shall have no greater right to assume or assign this Lease or any interest in this Lease, or to sublease any of the Premises than accorded to Tenant in Article 9, except to the extent Landlord shall be required to permit such assumption, assignment or sublease by the provisions of such Debtor’s Law. Without limitation of the generality of the foregoing, any right of any Tenant’s Representative to assume or assign this Lease or to sublease any of the Premises shall be subject to the conditions that:

20.1.1.1     Such Debtor’s Law shall provide to Tenant’s Representative a right of assumption of this Lease which Tenant’s Representative shall have timely exercised and Tenant’s Representative shall have fully cured any default of Tenant under this Lease.

20.1.1.2     Tenant’s Representative or the proposed assignee, as the case shall be, shall have deposited with Landlord as security for the timely payment of rent an amount equal to the larger of: (a) three (3) months’ rent and other monetary charges accruing under this Lease; and (b) any sum specified in Article 5; and shall have provided Landlord with adequate other assurance of the future performance of the obligations of the Tenant under this Lease. Without limitation, such assurances shall include, at least, in the case of assumption of this Lease, demonstration to the satisfaction of the Landlord that Tenant’s Representative has and will continue to have sufficient unencumbered assets after the payment of all secured obligations and administrative expenses to assure Landlord that Tenant’s

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Representative will have sufficient funds to fulfill the obligations of Tenant under this Lease; and, in the case of assignment, submission of current financial statements of the proposed assignee, audited by an independent certified public accountant reasonably acceptable to Landlord and showing a net worth and working capital in amounts determined by Landlord to be sufficient to assure the future performance by such assignee of all of the Tenant’s obligations under this Lease.

20.1.1.3     The assumption or any contemplated assignment of this Lease or subleasing any part of the Premises, as shall be the case, will not breach any provision in any other lease, mortgage, financing agreement or other agreement by which Landlord is bound.

20.1.1.4     Landlord shall have, or would have had absent the Debtor’s Law, no right under Article 9 to refuse consent to the proposed assignment or sublease by reason of the identity or nature of the proposed assignee or sublessee or the proposed use of the Premises concerned.

21.    QUIET ENJOYMENT. Landlord represents and warrants that it has full right and authority to enter into this Lease and that Tenant, while paying the rental and performing its other covenants and agreements contained in this Lease, shall peaceably and quietly have, hold and enjoy the Premises for the Term without hindrance or molestation from Landlord subject to the terms and provisions of this Lease. Landlord shall not be liable for any interference or disturbance by other tenants or third persons, nor shall Tenant be released from any of the obligations of this Lease because of such interference or disturbance.

22.    CASUALTY.

22.1    In the event the Premises or the Building are damaged by fire or other cause and in Landlord’s reasonable estimation such damage can be materially restored within one hundred eighty (180) days following the commencement of restoration, Landlord shall forthwith repair the same and this Lease shall remain in full force and effect, except that Tenant shall be entitled to a proportionate abatement in rent from the date of such damage. Such abatement of rent shall be made pro rata in accordance with the extent to which the damage and the making of such repairs shall interfere with the use and occupancy by Tenant of the Premises from time to time. Within forty-five (45) days from the date of such damage, Landlord shall notify Tenant, in writing, of Landlord’s reasonable estimation of the length of time within which material restoration can be made, and Landlord’s determination shall be binding on Tenant. For purposes of this Lease, the Building or Premises shall be deemed “materially restored” if they are in such condition as would not prevent or materially interfere with Tenant’s use of the Premises for the purpose for which it was being used immediately before such damage.

22.2    If such repairs cannot, in Landlord’s reasonable estimation, be made within one hundred eighty (180) days following the commencement of restoration, or if the damage to the Building occurs in the last year of the term of this Lease, Landlord and Tenant shall each have the option of giving the other, at any time within thirty (30) days after Landlord’s notice of estimated restoration time, notice terminating this Lease as of the date of such damage. In the event of the giving of such notice, this Lease shall expire and all interest of the Tenant in the Premises shall terminate as of the date of such damage as if such date had been originally fixed in this Lease for the expiration of the Term. In the event that neither Landlord nor Tenant exercises its option to terminate this Lease, then Landlord shall repair or restore such damage, this Lease continuing in full force and effect, and the rent hereunder shall be proportionately abated as provided in Section 22.1.

22.3    Landlord shall not be required to repair or replace any damage or loss by or from fire or other cause to any panelings, decorations, partitions, additions, railings, ceilings, floor coverings, office

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fixtures or any other property or improvements to the extent any of the foregoing are installed on the Premises by, or belonging to, Tenant. Any insurance which may be carried by Landlord or Tenant against loss or damage to the Building or Premises shall be for the sole benefit of the party carrying such insurance and under its sole control.

22.4    In the event that Landlord should fail to complete such repairs and material restoration within forty-five (45) days after the date estimated by Landlord therefor as extended by this Section 22.4, Tenant may at its option and as its sole remedy terminate this Lease by delivering written notice to Landlord, within fifteen (15) days after the expiration of said period of time, whereupon the Lease shall end on the date of such notice or such later date fixed in such notice as if the date of such notice was the date originally fixed in this Lease for the expiration of the Term; provided, however, that if construction is delayed because of changes, deletions or additions in construction requested by Tenant, strikes, lockouts, casualties, Acts of God, war, material or labor shortages, government regulation or control or other causes beyond the reasonable control of Landlord, the period for restoration, repair or rebuilding shall be extended for the amount of time Landlord is so delayed.

22.5    Notwithstanding anything to the contrary contained in this Article: (a) Landlord shall not have any obligation whatsoever to repair, reconstruct, or restore the Premises when the damages resulting from any casualty covered by the provisions of this Article 22 occur during the last twelve (12) months of the Term, or for which sufficient insurance proceeds to fully cover the repair and restoration are not received by Landlord, but if Landlord determines not to repair such damages Landlord shall notify Tenant and if such damages shall render any material portion of the Premises or common areas of Building untenantable Tenant shall have the right to terminate this Lease by notice to Landlord within fifteen (15) days after receipt of Landlord’s notice; and (b) in the event the holder of any indebtedness secured by a mortgage or deed of trust covering the Premises or Building requires that any insurance proceeds be applied to such indebtedness, then Landlord shall have the right to terminate this Lease by delivering written notice of termination to Tenant within fifteen (15) days after such requirement is made by any such holder, whereupon this Lease shall end on the date of such damage as if the date of such damage were the date originally fixed in this Lease for the expiration of the Term.

22.6    In the event of any damage or destruction to the Building or Premises by any peril covered by the provisions of this Article 22, it shall be Tenant’s responsibility to properly secure the Premises and upon notice from Landlord to remove forthwith, at its sole cost and expense, such portion of all of the property belonging to Tenant or its licensees from such portion or all of the Building or Premises as Landlord shall request.

23.    EMINENT DOMAIN. If all or any substantial part of the Premises shall be taken or appropriated by any public or quasi-public authority under the power of eminent domain, or conveyance in lieu of such appropriation, either party to this Lease shall have the right, at its option, of giving the other, at any time within thirty (30) days after such taking, notice terminating this Lease, except that Tenant may only terminate this Lease by reason of taking or appropriation, if such taking or appropriation shall be so substantial as to materially interfere with Tenant’s use and occupancy of the Premises. If neither party to this Lease shall so elect to terminate this Lease, the rental thereafter to be paid shall be adjusted on a fair and equitable basis under the circumstances. In addition to the rights of Landlord above, if any substantial part of the Building shall be taken or appropriated by any public or quasi-public authority under the power of eminent domain or conveyance in lieu thereof, and regardless of whether the Premises or any part thereof are so taken or appropriated, Landlord shall have the right, at its sole option, to terminate this Lease. Landlord shall be entitled to any and all income, rent, award, or any interest whatsoever in or upon any such sum, which may be paid or made in connection with any such public or

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quasi-public use or purpose, and Tenant hereby assigns to Landlord any interest it may have in or claim to all or any part of such sums, other than any separate award which may be made with respect to Tenant’s trade fixtures and moving expenses; Tenant shall make no claim for the value of any unexpired Term.

24.    SALE BY LANDLORD. In event of a sale or conveyance by Landlord of the Building, the same shall operate to release Landlord from any future liability upon any of the covenants or conditions, expressed or implied, contained in this Lease in favor of Tenant, and in such event Tenant agrees to look solely to the responsibility of the successor in interest of Landlord in and to this Lease, except that Landlord shall not be released from its obligation to return the security deposit required under this Lease unless and until Landlord transfers such security deposit to such assignee or transferee of the Lease. Except as set forth in this Article 24, this Lease shall not be affected by any such sale and Tenant agrees to attorn to the purchaser or assignee. If any security has been given by Tenant to secure the faithful performance of any of the covenants of this Lease, Landlord shall transfer or deliver said security, as such, to Landlord’s successor in interest and thereupon Landlord shall be discharged from any further liability with regard to said security.

25.    ESTOPPEL CERTIFICATES. Within ten (10) days following any written request which Landlord may make from time to time, Tenant shall execute and deliver to Landlord or mortgagee or prospective mortgagee a sworn statement certifying: (a) the date of commencement of this Lease; (b) the fact that this Lease is unmodified and in full force and effect (or, if there have been modifications to this Lease, that this Lease is in full force and effect, as modified, and stating the date and nature of such modifications); (c) the date to which the rent and other sums payable under this Lease have been paid; (d) the fact that there are no current defaults under this Lease by either Landlord or Tenant except as specified in Tenant’s statement (or, if there are current defaults under this Lease, stating the and nature of such defaults); and (e) such other matters as may be reasonably requested by Landlord. Landlord and Tenant intend that any statement delivered pursuant to this Article 25 may be relied upon by any mortgagee, beneficiary or purchaser, and Tenant shall be liable for all loss, cost or expense resulting from the failure of any sale or funding of any loan caused by any material misstatement contained in such estoppel certificate. Tenant irrevocably agrees that if Tenant fails to execute and deliver such certificate within such ten (10) day period Landlord or Landlord’s beneficiary or agent may execute and deliver such certificate on Tenant’s behalf, and that such certificate shall be fully binding on Tenant except to the extent Landlord knowingly makes misstatements of material facts in such certificate.

26.    SURRENDER OF PREMISES.

26.1    Tenant shall arrange to meet Landlord for two (2) joint inspections of the Premises, the first to occur at least thirty (30) days (but no more than sixty (60) days) before the last day of the Term, and the second to occur not later than forty-eight (48) hours after Tenant has vacated the Premises.

26.2    All alterations, additions, and improvements in, on, or to the Premises made or installed by or for Tenant, including, without limitation, carpeting (collectively, “Alterations”), shall be and remain the property of Tenant during the Term. Upon the expiration or sooner termination of the Term, all Alterations shall become a part of the realty and shall belong to Landlord without compensation, and title shall pass to Landlord under this Lease as by a bill of sale. At the end of the Term or any renewal of the Term or other sooner termination of this Lease, Tenant will peaceably deliver up to Landlord possession of the Premises, together with all Alterations by whomsoever made, in the same conditions received or first installed, broom clean and free of all debris, excepting only ordinary wear and tear and damage by fire or other casualty. Notwithstanding the foregoing, (i) Landlord shall notify Tenant, at the time Landlord approves the final construction drawings for Landlord’s Work, whether any portions of the Landlord’s

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Work will be required to be removed by Tenant at the end of the Term, (ii) Tenant shall have no obligation to remove any carpeting from the Premises, and (iii) for Alterations made during the Term, Landlord shall notify Tenant, at the time Landlord approves or consents to such Alterations, whether any such Alterations will be required to be removed by Tenant at the end of the Term. Any such required removal by Tenant shall be at Tenant’s sole cost, and Tenant shall repair any damage caused by such removal. Tenant must, at Tenant’s sole cost, remove upon termination of this Lease, any and all of Tenant’s furniture, furnishings, equipment, movable partitions of less than full height from floor to ceiling and other trade fixtures and personal property, as well as all data/telecommunications cabling and wiring installed by or on behalf of Tenant, whether inside walls, under any raised floor or above any ceiling (collectively, “Personalty”). Personalty not so removed shall be deemed abandoned by the Tenant and title to the same shall thereupon pass to Landlord under this Lease as by a bill of sale, but Tenant shall remain responsible for the cost of removal and disposal of such Personalty, as well as any damage caused by such removal. In lieu of requiring Tenant to remove Alterations and Personalty and repair the Premises as aforesaid, Landlord may, by written notice to Tenant delivered at least thirty (30) days before the Termination Date, require Tenant to pay to Landlord, as additional rent hereunder, the cost of such removal and repair in an amount reasonably estimated by Landlord.

26.3    All obligations of Tenant under this Lease not fully performed as of the expiration or earlier termination of the Term shall survive the expiration or earlier termination of the Term Upon the expiration or earlier termination of the Term, Tenant shall pay to Landlord the amount, as estimated by Landlord, necessary to repair and restore the Premises as provided in this Lease and/or to discharge Tenant’s obligation for unpaid amounts due or to become due to Landlord. All such amounts shall be used and held by Landlord for payment of such obligations of Tenant, with Tenant being liable for any additional costs upon demand by Landlord, or with any excess to be returned to Tenant after all such obligations have been determined and satisfied. Any otherwise unused Security Deposit shall be credited against the amount payable by Tenant under this Lease.

27.    NOTICES. Any notice or document required or permitted to be delivered under this Lease shall be addressed to the intended recipient, by fully prepaid registered or certified United States Mail return receipt requested, or by reputable independent contract delivery service furnishing a written record of attempted or actual delivery, and shall be deemed to be delivered when tendered for delivery to the addressee at its address set forth on the Reference Pages, or at such other address as it has then last specified by written notice delivered in accordance with this Article 27, or if to Tenant at either its aforesaid address or its last known registered office or home of a general partner or individual owner, whether or not actually accepted or received by the addressee. Any such notice or document may also be personally delivered if a receipt is signed by and received from, the individual, if any, named in Tenant’s Notice Address.

28.    TAXES PAYABLE BY TENANT. In addition to rent and other charges to be paid by Tenant under this Lease, Tenant shall reimburse to Landlord, upon demand, any and all taxes payable by Landlord (other than net income taxes) whether or not now customary or within the contemplation of the parties to this Lease: (a) upon, allocable to, or measured by or on the gross or net rent payable under this Lease, including without limitation any gross income tax or excise tax levied by the State, any political subdivision thereof, or the Federal Government with respect to the receipt of such rent; (b) upon or with respect to the possession, leasing, operation, management, maintenance, alteration, repair, use or occupancy of the Premises or any portion thereof, including any sales, use or service tax imposed as a result thereof; (c) upon or measured by the Tenant’s gross receipts or payroll or the value of Tenant’s equipment, furniture, fixtures and other personal property of Tenant or leasehold improvements, alterations or additions located in the Premises; or (d) upon this transaction or any document to which

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Tenant is a party creating or transferring any interest of Tenant in this Lease or the Premises. In addition to the foregoing, Tenant agrees to pay, before delinquency, any and all taxes levied or assessed against Tenant and which become payable during the term hereof upon Tenant’s equipment, furniture, fixtures and other personal property of Tenant located in the Premises.

29.    RELOCATION OF TENANT. Landlord, at its sole expense, on at least sixty (60) days prior written notice, may require Tenant to move from the Premises to other space on floors five (5) through eight (8) of comparable size and decor in order to permit Landlord to consolidate the space leased to Tenant with other adjoining space leased or to be leased to another tenant. In the event of any such relocation, Landlord will pay all expenses of preparing and decorating the new premises so that they will be the same or better than the Premises from which Tenant is moving, and Landlord will also pay the expense of moving Tenant’s furniture and equipment to the relocated premises. In such event this Lease and each and all of the terms and covenants and conditions hereof shall remain in full force and effect and thereupon be deemed applicable to such new space except that revised Reference Pages and a revised Exhibit A shall become part of this Lease and shall reflect the location of the new premises.

30.    DEFINED TERMS AND HEADINGS. The Article headings shown in this Lease are for convenience of reference and shall in no way define, increase, limit or describe the scope or intent of any provision of this Lease. Any indemnification or insurance of Landlord shall apply to and inure to the benefit of all the following “Landlord Entities”, being Landlord, Landlord’s investment manager, and the trustees, boards of directors, officers, general partners, beneficiaries, stockholders, employees and agents of each of them. Any option granted to Landlord shall also include or be exercisable by Landlord’s trustee, beneficiary, agents and employees, as the case may be. In any case where this Lease is signed by more than one person, the obligations under this Lease shall be joint and several. The terms “Tenant” and “Landlord” or any pronoun used in place thereof shall indicate and include the masculine or feminine, the singular or plural number, individuals, firms or corporations, and their and each of their respective successors, executors, administrators and permitted assigns, according to the context hereof. The term “rentable area” shall mean the rentable area of the Premises or the Building as calculated by the Landlord on the basis of the plans and specifications of the Building including a proportionate share of any common areas. Tenant hereby accepts and agrees to be bound by the figures for the rentable square footage of the Premises and Tenant’s Proportionate Share shown on the Reference Pages; however, Landlord may adjust either or both figures if there is manifest error, addition or subtraction to the Building or any business park or complex of which the Building is a part, remeasurement or other circumstance reasonably justifying adjustment. The term “Building” refers to the structure in which the Premises are located and the common areas (parking lots, sidewalks, landscaping, etc.) appurtenant thereto. If the Building is part of a larger complex of structures, the term “Building” may include the entire complex, where appropriate (such as shared Expenses, Insurance Costs or Taxes) and subject to Landlord’s reasonable discretion.

31.    TENANT’S AUTHORITY. If Tenant signs as a corporation, partnership, trust or other legal entity each of the persons executing this Lease on behalf of Tenant represents and warrants that Tenant has been and is qualified to do business in the state in which the Building is located, that the entity has full right and authority to enter into this Lease, and that all persons signing on behalf of the entity were authorized to do so by appropriate actions. Tenant agrees to deliver to Landlord, simultaneously with the delivery of this Lease, a corporate resolution, proof of due authorization by partners, opinion of counsel or other appropriate documentation reasonably acceptable to Landlord evidencing the due authorization of Tenant to enter into this Lease.

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Tenant hereby represents and warrants that neither Tenant, nor any persons or entities holding any legal or beneficial interest whatsoever in Tenant, are (i) the target of any sanctions program that is established by Executive Order of the President or published by the Office of Foreign Assets Control, U.S. Department of the Treasury (“OFAC”); (ii) designated by the President or OFAC pursuant to the Trading with the Enemy Act, 50 U.S.C. App. § 5, the International Emergency Economic Powers Act, 50 U.S.C. §§ 1701-06, the Patriot Act, Public Law 107-56, Executive Order 13224 (September 23, 2001) or any Executive Order of the President issued pursuant to such statutes; or (iii) named on the following list that is published by OFAC: “List of Specially Designated Nationals and Blocked Persons.” If the foregoing representation is untrue at any time during the Term, an Event of Default will be deemed to have occurred, without the necessity of notice to Tenant.

32.    FINANCIAL STATEMENTS AND CREDIT REPORTS. At Landlord’s request, and subject to a confidentiality agreement reasonably acceptable to both Landlord and Tenant, Tenant shall deliver to Landlord a copy, certified by an officer of Tenant as being a true and correct copy, of Tenant’s most recent audited financial statement, or, if unaudited, certified by Tenant’s chief financial officer as being true, complete and correct in all material respects. Tenant hereby authorizes Landlord to obtain one or more credit reports on Tenant at any time, and shall execute such further authorizations as Landlord may reasonably require in order to obtain a credit report. The obligations set forth in this Section 32 shall be suspended for all periods of time during which Tenant is a “public company” and subject to the public reporting obligations of the Securities Act of 1934, as amended.

33.    COMMISSIONS. Each of the parties represents and warrants to the other that it has not dealt with any broker or finder in connection with this Lease, except as described on the Reference Pages. Landlord understands and acknowledges that it shall be responsible for payment of any commissions owed to the brokers described on the Reference Pages and shall indemnify and hold Tenant harmless against any non-payment of such commissions.

34.    TIME AND APPLICABLE LAW. Time is of the essence of this Lease and all of its provisions. This Lease shall in all respects be governed by the laws of the state in which the Building is located. Whenever a period of time is prescribed for the taking of an action by Landlord, the period of time for the performance of such action shall be extended by the number of days that the performance is actually delayed due to strikes, acts of God, shortages of labor or materials, war, terrorist acts, pandemics, civil disturbances and other causes beyond the reasonable control of the performing party.

35.    SUCCESSORS AND ASSIGNS. Subject to the provisions of Article 9, the terms, covenants and conditions contained in this Lease shall be binding upon and inure to the benefit of the heirs, successors, executors, administrators and assigns of the parties to this Lease.

36.    ENTIRE AGREEMENT. This Lease, together with its exhibits, contains all agreements of the parties to this Lease and supersedes any previous negotiations. There have been no representations made by the Landlord or any of its representatives or understandings made between the parties other than those set forth in this Lease and its exhibits. This Lease may not be modified except by a written instrument duly executed by the parties to this Lease.

37.    EXAMINATION NOT OPTION. Submission of this Lease shall not be deemed to be a reservation of the Premises. Landlord shall not be bound by this Lease until it has received a copy of this Lease duly executed by Tenant and has delivered to Tenant a copy of this Lease duly executed by Landlord, and until such delivery Landlord reserves the right to exhibit and lease the Premises to other prospective tenants. Notwithstanding anything contained in this Lease to the contrary, Landlord may

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withhold delivery of possession of the Premises from Tenant until such time as Tenant has paid to Landlord any security deposit required by Article 5, the first month’s rent as set forth in Article 3 and any sum owed pursuant to this Lease.

38.    RECORDATION. Tenant shall not record or register this Lease or a short form memorandum hereof without the prior written consent of Landlord, and then shall pay all charges and taxes incident such recording or registration.

39.    PARKING.

39.1    During the initial Term of this Lease, Tenant agrees to lease from Landlord and Landlord agrees to lease to Tenant, the number and type of parking passes as set forth on the Reference Page of this Lease. This right to park in the Building’s parking facilities (the “Parking Facility”) shall be on an unreserved, nonexclusive, first come, first served basis, for passenger-size automobiles and is subject to the following terms and conditions:

39.1.1    Tenant shall pay to Landlord, or Landlord’s designated parking operator, the Building’s prevailing monthly parking charges, without deduction or offset, on the first day of each month during the Term of this Lease. Landlord will notify Tenant upon not less than thirty (30) days’ notice of any increases in the monthly parking charges prior to billing Tenant any increases. No deductions from the monthly charge shall be made for days on which the Parking Facility is not used by Tenant.

39.1.2    Tenant shall at all times abide by and shall cause each of Tenant’s employees, agents, customers, visitors, invitees, licensees, contractors, assignees and subtenants (collectively, “Tenant’s Parties”) to abide by any rules and regulations (“Rules”) for use of the Parking Facility that Landlord or Landlord’s garage operator reasonably establishes from time to time, and otherwise agrees to use the Parking Facility in a safe and lawful manner. Landlord reserves the right to adopt, modify and enforce the Rules governing the use of the Parking Facility from time to time including any key-card, sticker or other identification or entrance system and hours of operation. Landlord may refuse to permit any person who violates such Rules to park in the Parking Facility, and any violation of the Rules shall subject the car to removal from the Parking Facility.

39.1.3    Unless specified to the contrary above, the parking spaces hereunder shall be provided on a non-designated “first-come, first-served” basis. Landlord reserves the right to assign specific spaces, and to reserve spaces for visitors, small cars, disabled persons or for other tenants or guests, and Tenant shall not park and shall not allow Tenant’s Parties to park in any such assigned or reserved spaces; provided however, that Landlord shall manage the parking garage to ensure that the parking space is available to Tenant as per this Section 39. Tenant may validate visitor parking by such method as Landlord may approve, at the validation rate from time to time generally applicable to visitor parking. Tenant acknowledges that the Parking Facility may be closed entirely or in part in order to make repairs or perform maintenance services, or to alter, modify, re-stripe or renovate the Parking Facility, or if required by casualty, strike, condemnation, act of God, governmental law or requirement or other reason beyond the operator’s reasonable control.

39.1.4    Tenant acknowledges that to the fullest extent permitted by law, Landlord shall have no liability for any damage to property or other items located in the parking areas of the Building (including without limitation, any loss or damage to tenant’s automobile or the contents thereof due to theft, vandalism or accident), nor for any personal injuries or death arising out of the use of the Parking

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Facility by Tenant or any Tenant’s Parties, whether or not such loss or damage results from Landlord’s active negligence or negligent omission. The limitation on Landlord’s liability under the preceding sentence shall not apply however to loss or damage arising directly from Landlord’s willful misconduct. Without limiting the foregoing, if Landlord arranges for the parking areas to be operated by an independent contractor not affiliated with Landlord, Tenant acknowledges that Landlord shall have no liability for claims arising through acts or omissions of such independent contractor. Tenant and Tenant’s Parties each hereby voluntarily releases, discharges, waives and relinquishes any and all actions or causes of action for personal injury or property damage occurring to Tenant or any of Tenant’s Parties arising as a result of parking in the Parking Facility, or any activities incidental thereto, wherever or however the same may occur, and further agrees that Tenant will not prosecute any claim for personal injury or property damage against Landlord or any of its officers, agents, servants or employees for any said causes of action and in all events, Tenant agrees to look first to its insurance carrier and to require that Tenant’s Parties look first to their respective insurance carriers for payment of any losses sustained in connection with any use of the Parking Facility. Tenant hereby waives on behalf of its insurance carriers all rights of subrogation against Landlord or any Landlord Entities.

39.1.5    Tenant’s right to park as described in this Article and this Lease is exclusive to Tenant and shall not pass to any assignee or sublessee without the express written consent of Landlord other than any assignee or sublessee where Landlord’s consent is not required for the assignment or sublet pursuant to Section 9. Such consent is at the sole discretion of the Landlord.

39.1.6    In the event any surcharge or regulatory fee is at any time imposed by any governmental authority with reference to parking, Tenant shall (commencing after two (2) weeks’ notice to Tenant) pay, per parking pass, such surcharge or regulatory fee to Landlord in advance on the first day of each calendar month concurrently with the month installment of rent due under this Lease. Landlord will enforce any surcharge or fee in an equitable manner amongst the Building tenants.

39.2    If Tenant violates any of the terms and conditions of this Article, the operator of the Parking Facility shall have the right to remove from the Parking Facility any vehicles hereunder which shall have been involved or shall have been owned or driven by parties involved in causing such violation, without liability therefor whatsoever. In addition, Landlord shall have the right to cancel Tenant’s right to use the Parking Facility pursuant to this Article upon ten (10) days’ written notice, unless within such ten (10) day period, Tenant cures such default. Such cancellation right shall be cumulative and in addition to any other rights or remedies available to Landlord at law or equity, or provided under this Lease.

40.    LIMITATION OF LANDLORD’S LIABILITY. Redress for any claim against Landlord under this Lease shall be limited to and enforceable only against and to the extent of Landlord’s interest in the Building. The obligations of Landlord under this Lease are not intended to be and shall not be personally binding on, nor shall any resort be had to the private properties of, any of its or its investment manager’s trustees, directors, officers, partners, beneficiaries, members, stockholders, employees, or agents, and in no case shall Landlord be liable to Tenant hereunder for any lost profits, damage to business, or any form of special, indirect or consequential damages.

41.    EXTENSION OPTION. Tenant shall, provided the Lease is in full force and effect and there is no uncured Event of Default at the time of notification or commencement, have one (1) option to extend the Term of this Lease as to the entire Premises for a term of five (5) years (the “Extension Term”), on

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the same terms and conditions set forth in the Lease, except as modified by the terms, covenants and conditions as set forth below:

41.1    If Tenant elects to exercise said option, then Tenant shall provide Landlord with written notice no earlier than the date which is fifteen (15) months prior to the expiration of the then current Term of the Lease but no later than the date which is twelve (12) months prior to the expiration of the then current Term of this Lease. If Tenant fails to provide such notice, time being of the essence, Tenant shall have no further or additional right to extend or renew the term of the Lease.

41.2    The Annual Rent and Monthly Installment in effect at the expiration of the then current term of the Lease shall be increased for the Extension Term as hereinafter provided. The Annual Rent and Monthly Installment for the Extension Term shall be increased to equal the then current fair market rental for comparable space in similar buildings in the same rental market as of the date the applicable Extension Term is to commence, taking into account the specific provisions of the Lease which will remain constant. Landlord shall advise Tenant of the new Annual Rent and Monthly Installment for the Premises no later than thirty (30) days after receipt of Tenant’s written request to exercise an Extension Term. Said request shall be made no earlier than thirty (30) days prior to the first date on which Tenant may exercise its option under this Paragraph. Said notification of the new Annual Rent may include a provision for its escalation to provide for a change in fair market rental between the time of notification and the commencement of the extension term. If, on or before the date which is 270 days prior to the commencement of the applicable Extension Term, Tenant has not agreed with Landlord’s determination of the new Annual Rent after negotiating in good faith, either party may elect by notice (the “Arbitration Notice”) to the other party to have the new Annual Rent arbitrated as described as follows.

41.3    If either party sends the Arbitration Notice, then such new Annual Rent shall be determined as follows: Landlord and Tenant shall each appoint a qualified MAI appraiser doing business in the area and, in turn, those two (2) independent MAI appraisers shall appoint a third (3^rd) MAI appraiser and the majority shall decide the new Annual Rent for the Premises as of the commencement of the applicable Extension Term, which determination shall be consistent with the second sentence of Section 41.2 above and shall be binding on Landlord and Tenant. Landlord and Tenant shall equally share in the expense of this appraisal.

41.4    A qualified MAI appraiser shall be any person appointed by or on behalf of either party or appointed pursuant to the provisions hereof and: (i) shall be (A) a member of the American Institute of Real Estate Appraisers with not less than 10 years of experience in the appraisal of improved office and life sciences space in the greater Cambridge, Massachusetts metropolitan area, or (B) a licensed commercial real estate broker with not less than 15 years’ experience representing landlords and/or tenants in the leasing of office and life sciences space in the greater Cambridge, Massachusetts metropolitan area; (ii) devoting substantially all of his or her time to professional appraisal or brokerage work, as applicable, at the time of appointment; and (iii) shall be in all respects impartial and disinterested.

In no event shall the Annual Rent and Monthly Installment for any option period be less than the Annual Rent and Monthly Installment in the preceding Term and escalating each Lease Year by 3%.

41.5    Except as set forth below, the option to extend the Term for the Extension Term is not transferable; the parties hereto acknowledge and agree that they intend that the aforesaid option to extend the Term of this Lease shall be “personal” to the originally-named Tenant as set forth above and that in no event will any assignee or sublessee have any rights to exercise the aforesaid option to extend, other than an assignee who has consummated a Permitted Transfer.

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IN WITNESS WHEREOF, Landlord and Tenant have executed the Lease as of the Lease Reference Date set forth above.

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