LEASE LANDLORD: WALTHAM WINTER STREET 890 LP TENANT: ARSANIS, INC. Lease Dated: October 30, 2015

Exhibit 10.16

EXECUTION COPY

LEASE

LANDLORD:

WALTHAM WINTER STREET 890 LP

TENANT:

ARSANIS, INC.

Lease Dated: October 30, 2015

ARTICLE I

DEMISING CLAUSE AND DEFINED TERMS

1.1 Demising Clause.

This lease (this “Lease”) is made and entered into by and between the Landlord and the Tenant, as defined below, as of the date set forth above. In consideration of the mutual covenants made herein, Landlord hereby leases to Tenant, and Tenant hereby leases from Landlord, the Premises as, defined below, on all of the terms and conditions set forth herein.

1.2 Defined Terms.

The terms listed below shall have the following meanings throughout this Lease:

LANDLORD:		Waltham Winter Street 890 LP, a
		Delaware limited partnership
LANDLORD’S ORIGINAL ADDRESS:		c/o Clarion Partners, LLC
		000 Xxxx Xxxxxx
		Xxxxxx, Xxxxxxxxxxxxx 00000
TENANT:		Arsanis, Inc., a
		Delaware corporation
TENANT’S ORIGINAL ADDRESS:		0 Xxxxxx Xxxxx
		Xxxxxxx, Xxx Xxxxxxxxx 00000
BUILDING:		The building located at 000 Xxxxxx Xxxxxx, Xxxxxxx, Xxxxxxxxxxxxx, and located on the parcel of land (the “Lot”) described in Exhibit A.
PROPERTY:		The Building and the Lot.
TENANT’S SPACE:		7,814 rentable square feet (“RSF”) on the second (2nd) floor of the Building, as shown on Exhibit B.
COMMENCEMENT DATE:		November 1, 2015.
RENT COMMENCEMENT DATE:		February 1, 2016 (subject to extension
		pursuant to Section 2.6).
TERM:		The term commencing on the Commencement Date and ending on the date which is three (3) years and three (3) months following the Commencement

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		Date.
FIXED RENT:		Per Annum		Per Month
Commencing on the Rent Commencement Date through the last day immediately preceding the first anniversary of the Rent Commencement Date:		$300,839.00		$25,069.92
Commencing on the first anniversary of the Rent Commencement Date through the last day immediately preceding the second anniversary of the Rent Commencement Date:		$308,653.00		$25,721.08
Commencing on the second anniversary of the Rent Commencement Date through the last day of the Term:		$316,467.00		$26,372.25
TENANT’S OPERATING EXPENSE BASE:		Tenant’s Proportionate Share of the total Operating Expenses for the Property incurred during calendar year 2016 (January 1, 2016 through December 31, 2016).
TENANT’S TAX BASE:		Tenant’s Proportionate Share of the fiscal year 2016 Real Estate Taxes for the Property (July 1, 2015 through June 30, 2016), as adjusted by the results of any abatement, reassessment or litigation.
TOTAL RENTABLE FLOOR AREA OF THE BUILDING:		173,070 rentable square feet.
TENANT’S PROPORTIONATE SHARE:		Tenant’s Proportionate Share is based on a fraction, the total rentable square feet of the Building as the denominator (173,070 sq. ft.) and the total rentable square feet of the Premises as the numerator (7,814 sq. ft.). Tenant’s Proportionate Share is four and fifty-one one hundredths percent (4.51%).
PERMITTED USES:		General office use and uses ancillary thereto, and for no other purpose.
SECURITY DEPOSIT:		See Section 8.17

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BROKER: Transwestern/RBJ and Xxxxx Xxxx LaSalle (collectively, the “Broker”)

1.3 Exhibits.

There are incorporated as a part of this Lease:

EXHIBIT A		-		Property Description
EXHIBIT B		-		Floor Plan
EXHIBIT C		-		Reserved
EXHIBIT D		-		Landlord’s Services
EXHIBIT E		-		Rules and Regulations
EXHIBIT F		-		Insurance Requirements

1.4 Table of Contents

ARTICLE I
		DEMISING CLAUSE AND DEFINED TERMS			1
1.1		Demising Clause			1
1.2		Defined Terms			1
1.3		Exhibits			3
1.4		Table of Contents			3
ARTICLE II
		PREMISES, TERM AND RENT			1
2.1		The Premises			1
2.2		Parking			1
2.3		Rights to Use Common Facilities			1
2.4		Landlord’s Reservation			1
2.5		Habendum: Commencement Date			2
2.6		Monthly Fixed Rent Payments			3
2.7		Adjustments for Operating Expenses			3
2.8		Adjustments for Real Estate Taxes			6
2.9		Electricity Charge			7
2.10		Due Date of Additional Payments; No Offsets			8
2.11		Late Payment of Rent			8
2.12		Renewal Option			8

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ARTICLE III
		CONSTRUCTION			10
3.1		Premises As Is			10
3.2		Landlord’s Work			10
3.3		General Provisions Applicable to Construction			10
3.4		Liens			10
ARTICLE IV
		LANDLORD’S COVENANTS; INTERRUPTIONS AND DELAYS			10
4.1		Services Furnished by Landlord			10
4.2		Additional Services Available to Tenant			11
4.3		Roof, Exterior Wall, Floor Slab and Common Facility Repair			11
4.4		Quiet Enjoyment			11
4.5		Interruptions and Delays in Service and Repairs, etc.			11
4.6		Payment of Legal Expenses			12
4.7		Landlord to Maintain Insurance; Waiver of Subrogation			12
ARTICLE V
		TENANT’S COVENANTS			13
5.1		Payments			13
5.2		Repair and Yield Up			13
5.3		Use			14
5.4		Obstructions; Items Visible from Exterior; Rules and Regulations; Signs			14
5.5		Safety Appliances; Hazardous Materials			14
5.6		Assignment; Sublease			15
5.7		Indemnity; Insurance; Waiver of Subrogation			17
5.8		Personal Property at Tenant’s Risk			20
5.9		Right of Entry			21
5.10		Floor Load; Prevention of Vibration and Noise			21
5.11		Personal Property Taxes			21
5.12		Payment of Legal Expenses			21
5.13		Compliance with Insurance Regulations			21
ARTICLE VI
		CASUALTY AND TAKING			22
6.1		Termination or Restoration; Rent Adjustment			22
6.2		Eminent Domain Award			23
6.3		Temporary Taking			23
ARTICLE VII
		DEFAULT			23
7.1		Events of Default			23
7.2		Landlord’s Rights and Tenant’s Obligations after Termination			24

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ARTICLE VIII
		MISCELLANEOUS			25
8.1		Notice of Lease; Consent and Approval; Notices; Bind and Inure			25
8.2		Landlord’s Failure to Enforce			26
8.3		Acceptance of Partial Payments of Rent; Delivery of Keys			26
8.4		Cumulative Remedies			26
8.5		Partial Invalidity			26
8.6		Self-Help			27
8.7		Estoppel Certificate			27
8.8		Waiver of Subrogation			27
8.9		All Agreements Contained; Independent Covenants; Construction			28
8.10		Brokerage			28
8.11		Submission Not an Option			28
8.12		Applicable Law			28
8.13		Waiver of Jury Trial			28
8.14		Access and Security			28
8.15		Holdover			29
8.16		Limitation on Liability			29
8.17		Security Deposit [AMOUNT UNDER REVIEW]			29
8.18		Representations			30
ARTICLE IX
		RIGHTS OF PARTIES HOLDING PRIOR INTERESTS			30
9.1		Lease Subordinate			30
9.2		Rights of Holder of Mortgage to Notice of Defaults by Landlord and to Cure
		Same			31

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ARTICLE II

PREMISES, TERM AND RENT

2.1 The Premises

Landlord hereby leases to Tenant and Tenant hereby hires from Landlord Tenant’s Space in the Building, excluding exterior faces of exterior walls, the common stairways and stairwells, elevators and elevator shafts, the roof, storage areas, fan rooms, electric and telephone closets, janitor closets, freight elevator vestibules, and pipes, ducts, conduits, wires and appurtenant fixtures serving exclusively or in common other parts of the Building, and if Tenant’s Space includes less than the entire rentable area of any floor, excluding the common corridors, elevator lobbies and toilets located on such floor. Tenant’s Space with such exclusions is hereinafter referred to as the “Premises.”

2.2 Parking

Tenant and its employees and visitors shall be permitted to use twenty six (26) parking spaces in the parking areas on a non-exclusive basis in common with other Building tenants on the Lot, without charge, including two (2) non-exclusive spaces in the parking areas beneath the Building. Tenant shall not sublet, assign or otherwise transfer its right to use parking spaces in the garage beneath the Building without the prior written consent of Landlord except in connection with a sublease or assignment permitted under this Lease (including a sublease or assignment to a Tenant Affiliate (as defined in Section 5.6 below)).

2.3 Rights to Use Common Facilities

Tenant shall have, as appurtenant to the Premises, rights to use in common with others, subject to reasonable rules of general applicability to tenants of the Building from time to time made by Landlord of which Tenant is given notice: (a) the common lobbies, corridors, stairways, elevators and the pipes, ducts, conduits, wires and appurtenant meters and equipment serving the Premises, (b) common walkways and driveways necessary for access to the Building and the loading area in the rear of the Building, (c) to the extent made available for the general use of tenants and occupants of the Building, the Building conference room, café, fitness center, and other common areas of the Building or the office park in which the Building is located, and (d) if the Premises include less than the entire rentable area of any floor, the common toilets, corridors and elevator lobbies of such floor.

2.4 Landlord’s Reservation

Landlord reserves the right from time to time, without unreasonable interference with Tenant’s Permitted Use and upon reasonable prior notice: (a) to install, use, maintain, repair, replace and relocate for service to the Premises and other parts of the Building, or either, pipes, ducts, conduits, wires and appurtenant fixtures, wherever located in the Premises or Building, and (b) to alter or relocate any other common facility, provided that substitutions are substantially equivalent or better. Installations, replacements and relocations referred to in clause (a) above shall be located so far as practicable in the central core area of the Building, above ceiling surfaces, below floor surfaces or within perimeter walls of the Premises.

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2.5 Habendum: Commencement Date

Tenant shall have and hold the Premises for a period commencing on the Commencement Date and continuing for the Term unless sooner terminated as provided in Section 6.1 or ARTICLE VII or extended pursuant to Section 2.12. Notwithstanding the foregoing, Landlord, upon request by Tenant, shall grant to Tenant and Tenant’s agents a license to enter the Premises at any time from and after the date which Landlord reasonably determines to be twenty-one (21) days prior to the date Landlord’s Work (as defined herein) will be substantially completed for the purposes of installing Tenant’s furniture, fixtures, equipment and cabling in the Premises. It shall be a condition to the grant by Landlord and continued effectiveness of such license that:

(a) Tenant’s request for such early access shall be accompanied by: (i) a description of and schedule for the work to be performed by those persons and entities for whom such access is being requested; (ii) the names and addresses of all contractors for whom such early access is being requested and copies of all licenses and permits required in connection with the performance of the work for which such access is being requested; and (iii) certificates of insurance (in amounts and with insured parties satisfactory to Landlord). All of the foregoing shall be subject to Landlord’s reasonable approval.

(b) Such early access for installation purposes shall be subject to reasonable scheduling by Landlord.

(c) Tenant’s agents, contractors, workmen, mechanics, suppliers and invitees shall work in harmony and not interfere with (i) Landlord and Landlord’s agents in performing Landlord’s Work or work by Landlord or its agents in other premises or common areas of the Building, or (ii) the general operation of the Building. If at any time such entry shall cause or reasonably threaten to cause such disharmony or interference (including introducing union labor to the Building), Landlord may withdraw such license if, upon written notice to Tenant, Tenant fails to correct such interference within 24 hours.

Any such entry into and occupation of the Premises by Tenant shall be deemed to be under all of the terms, covenants, conditions and provisions of the Lease (including, without limitation, the insurance and indemnity provisions therein), excluding only the covenant to pay Fixed Rent, additional rent or electricity; provided, however, that, notwithstanding the foregoing, Tenant’s obligation to pay Fixed Rent, additional rent and electricity hereunder shall commence upon Tenant conducting any material and regular business activities at the Premises. Landlord shall not be liable for any injury, loss or damage which may occur to any of Tenant’s work or installations made in the Premises or to property placed therein prior to the commencement of the Term, the same being at Tenant’s sole risk and liability. Tenant shall be liable to Landlord for any damage to the Premises or to any portion of Landlord’s Work caused by Tenant or any of

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Tenant’s employees, agents, contractors, workmen or suppliers. In the event the performance of the work by Tenant, its agents, employees or contractors causes material extra costs to Landlord, Tenant shall reimburse Landlord for the entire extra cost upon receipt of substantiating backup of such cost.

2.6 Monthly Fixed Rent Payments

Tenant shall pay, commencing on the Rent Commencement Date, without notice, demand, offset or deduction, monthly installments of Fixed Rent in advance on the first day of each month to such person and at such place as Landlord shall from time to time designate by notice to Tenant. Landlord initially designates its address set forth in Section 1.2 for this purpose.

Fixed Rent for any partial calendar month following the Rent Commencement Date shall be prorated on a daily basis, and shall be due and payable in advance on the Rent Commencement Date.

If the Landlord’s Work is not substantially completed by November 15, 2015, then, excluding any delay caused by Tenant, the Rent Commencement Date will be extended for a period of time equal to (i) the total number of days between November 15, 2015 and the day on which the Landlord’s Work is substantially completed. In such circumstances, at the request of either Party, the Parties shall execute an amendment to the Lease solely for the purpose of implementing such modifications; provided, however, that such modifications shall be deemed to take effect immediately, whether or not such executed amendment to the Lease has been executed.

2.7 Adjustments for Operating Expenses

A. Terms used herein are defined as follows:

(1) “Operating Expenses for the Property” means the cost of operation of the Property which shall exclude costs of special services rendered to tenants (including Tenant) for which a separate charge is made and items of expense referred to in Section 2.8 hereof, but shall include, without limitation, the following: premiums for insurance carried with respect to the Property; compensation and all fringe benefits, worker’s compensation insurance premiums and payroll taxes paid to, for or with respect to all persons engaged in directly operating, repairing, maintaining, or cleaning of the Property; steam, water, sewer, electric, gas, oil and telephone and other utility charges; costs of building and cleaning supplies, materials and equipment; costs of maintenance, cleaning and repairs; costs of snow removal and care of landscaping; fees, expenses and contributions for the Building and Property to the common expenses of the office park in which they are located; payments under service contracts for any of the foregoing services with independent contractors or subsidiaries or affiliates of Landlord; management fees at reasonable rates consistent with the type of occupancy and the service rendered and all other reasonable and necessary expenses paid in connection with the operation, repair, cleaning and maintenance of the Property. Any of the services may be performed by subsidiaries or affiliates of Landlord, provided that the contracts for the performance of such services shall be competitive with comparable first class office buildings in the Boston metropolitan area.

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For purposes of the preceding definition, the Operating Expenses for the Property shall include the cost (amortized with interest using generally accepted accounting principles) of any capital improvement (including, without limitation any equipment installed as a fixture) made by Landlord for the purpose of (a) reducing other operating costs; or (b) complying with any governmental requirement (including, without limitation, any law, ordinance, code, regulation or bylaw) which shall first become applicable to the Property after the date of this Lease; or (c) such items as are required to keep the Building and Property as a first quality office building in the Boston metropolitan area.

Notwithstanding the foregoing, Operating Expenses for the Property shall exclude:

(a) Expenses for any item or service not provided to Tenant but provided exclusively to another tenant in that tenant’s space within the Building;

(b) Expenses for any item or service which Tenant pays directly to a third party or separately pays to Landlord (e.g., electricity);

(c) Landlord’s general corporate overhead and administrative expenses;

(d) Expenses incurred by Landlord to resolve disputes, enforce or negotiate lease terms with prospective or existing tenants or in connection with any financing, sale or syndication of the Property;

(e) Any cost incurred by the gross negligence or willful misconduct of the Landlord, its agents and employees;

(f) Penalties, fines and other costs incurred due to violation by the Landlord of any lease or any laws, rules, regulations or ordinances applicable to the Building and any interest or penalties due for late payment by Landlord of any of the Operating Expenses for the Property;

(g) Expenses incurred by Landlord to (i) lease space to new tenants or to retain existing tenants including leasing commissions, advertising and promotional expenditures, and (ii) prepare, renovate, repaint, redecorate or perform any other work in any space leased to an existing or prospective tenant or other occupant of the Building;

(h) Depreciation and amortization, except to the extent provided above;

(i) Interest, principal, points and fees, amortization or other costs and expenses associated with any debt or rent payable under any ground lease;

(j) Real Estate Taxes for the Property;

(k) Cost of alterations, capital improvements, equipment replacement and other items (including reserves for the same) which under generally accepted accounting principles are properly classified as capital expenditures except for capital expenditures to the extent expressly permitted above;

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(l) Payments for rented equipment, the cost of which equipment would constitute a capital expenditure if the equipment were purchased;

(m) Costs and expenses incurred by the Landlord in connection with the repair of damage to the Building or Property caused by fire or other casualty, insured or required to be insured against hereunder; and

(n) Costs and expenses of investigating, monitoring and remediating hazardous materials on, under or about the Building.

(2) The “Operating Statement” shall mean a statement rendered to Tenant by Landlord within approximately one hundred twenty (120) days or as soon thereafter as reasonably possible after the end of each calendar year during the Term. The Operating Statement shall be in reasonable detail, certified by Landlord’s representative, and show the amount of the Operating Expenses for the Property and the Operating Expenses Allocable to the Premises for the preceding calendar year or fraction thereof, as the case may be.

(3) The phrase “Operating Expenses Allocable to the Premises” means Tenant’s Proportionate Share of the Operating Expenses for the Property.

(4) In any calendar year when the Building has an average annual occupancy rate of less than ninety-five percent (95%), then, for the purpose of this Section 2.7, items which are variable according to occupancy comprising the Operating Expenses for the Property shall be equitably adjusted as though the Building were ninety-five percent (95%) occupied. In any calendar year when the Building has an average annual occupancy rate of ninety-five percent (95%) or more then the Operating Expenses for the Property shall be the actual Operating Expenses for the Property.

B. If, with respect to any calendar year or fraction thereof ending within the Term, the Operating Expenses Allocable to the Premises for a full calendar year exceed Tenant’s Operating Expense Base then, within thirty (30) days after receipt by Tenant of the Operating Statement, Tenant shall pay to Landlord, as additional rent, the amount of such excess, less any amounts previously paid by Tenant pursuant to Paragraph C below. In the event the actual amounts due for the period encompassed by Landlord’s statement are less than the estimated amounts theretofore paid by Tenant with respect to such period, Tenant shall receive a credit for the excess amounts paid, which credit may be applied against subsequent installments of additional rent due under this Section 2.7, or, if this Lease has already been terminated, Landlord shall refund such amounts to Tenant within 15 business days.

C. Landlord shall have the right from time to time by notice to Tenant to estimate amounts required to be paid by Tenant under this Section 2.7 to reflect Landlord’s latest reasonable estimate of the actual amounts which will be due from Tenant hereunder based upon then current budgets and expenditures incurred to date. Following any notice by Landlord requesting that Tenant make estimated monthly payments toward its obligation under this Section 2.7, Tenant shall make such monthly payments in accordance with such notice, until

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further notice is given by Landlord. If the Term of this Lease expires prior to the determination by Landlord and payment by or refund to Tenant of any amounts due hereunder, Tenant’s obligation to pay and Landlord’s obligation to refund such amounts for any portion of the Term of this Lease shall survive the termination of this Lease even though determination of such amounts may not be made until after such termination.

D. Landlord agrees to keep books and records showing Operating Expenses for the Property in accordance with a system of accounts and accounting practices consistently maintained. Tenant shall have the right, at its sole expense, upon reasonable prior notice to Landlord, to inspect such books and records at Landlord’s office during business hours for ninety days following receipt of an annual Operating Statement; provided, however, that such right may not be exercised by an agent of Tenant whose fee is based on the success of the inspection. Should such inspection reveal errors in excess of five percent (5%), Landlord shall reimburse Tenant for its reasonable out of pocket expenses of such inspection.

2.8 Adjustments for Real Estate Taxes

A. Terms used herein are defined as follows:

(1) “Tax Year” means the twelve-month period beginning July 1 each year during the Term or if the appropriate governmental tax fiscal period shall begin on any date other than July 1, such other date.

(2) “Landlord’s Tax Expenses” with respect to any Tax Year means the aggregate Real Estate Taxes for the Property with respect to that Tax Year, reduced by any abatements actually received with respect to that Tax Year.

(3) “Real Estate Taxes for the Property” means all taxes and special assessments of every kind and nature assessed by any governmental authority on the Lot or the Building or the Property which Landlord shall become obligated to pay because of or in connection with the ownership, leasing and operation of the Lot, the Building and the Property and reasonable expenses of any proceedings for abatement of taxes. The amount of special taxes or special assessments to be included shall be limited to the amount of the installment (plus any interest, other than penalty interest, payable thereon) of such special tax or special assessment required to be paid during the year in respect of which such taxes are being determined. There shall be excluded from such taxes all income, estate, succession, inheritance and transfer taxes and interest and penalties assessed by reason of Landlord’s failure to pay such real estate taxes when due; provided, however, that if at any time during the Term the present system of ad valorem tax of real property shall be changed so that in lieu of the whole or any part of the ad valorem tax on real property, there shall be assessed on Landlord a capital levy or other tax on the gross rents received with respect to the Lot or Building or Property, or a federal, state, county, municipal, or other local income, franchise, excise or similar tax, assessment, levy or charge (distinct from any now in effect in Massachusetts) measured by or based, in whole or in part, upon any such gross rents, then any and all of such taxes shall be included within the term “Real Estate Taxes for the Property.”

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(4) The “Tax Statement” shall mean a statement rendered to Tenant by Landlord within thirty (30) days or as soon thereafter as reasonably practical after receipt of the real estate tax bills for each Tax Year (or partial year, if applicable) during the Term and within ninety (90) days or as soon thereafter as reasonably practical after Lease termination. The Tax Statement shall be in reasonable detail showing for the respective Tax Year or fraction thereof, as the case may be, Real Estate Taxes for the Property.

(5) “Tax Expenses Allocable to the Premises” means Tenant’s Proportionate Share of Real Estate Taxes for the Property.

B. If with respect to any Tax Year, Tax Expenses Allocable to the Premises exceed Tenant’s Tax Base, then within thirty (30) days after receipt by Tenant of the Tax Statement, Tenant shall pay to Landlord, as additional rent, the amount of such excess, less any amounts previously paid by Tenant pursuant to Paragraph C below. In the event the actual amounts due for the period encompassed by the Tax Statement are less than the estimated amounts theretofore paid by Tenant with respect to such period, Tenant shall receive a credit for the excess amounts paid, which credit may be applied against subsequent installments of additional rent due under this Section 2.8, or, if this Lease has already been terminated, Landlord shall promptly refund such amounts to Tenant. Appropriate prorations shall be made for those periods at the beginning or end of the Term which are less than a full Tax Year.

C. Landlord shall have the right from time to time by notice to Tenant to estimate amounts required to be paid by Tenant under this Section 2.8 to reflect Landlord’s latest reasonable estimate of the actual amounts which will be due from Tenant hereunder. Following any notice by Landlord requesting that Tenant make estimated monthly payments toward its obligation under this Section 2.8, Tenant shall make such monthly payments in accordance with such notice, until further notice is given by Landlord. If the Term of this Lease expires prior to the determination by Landlord and payment by or refund to Tenant of any amounts due hereunder, Tenant’s obligation to pay and Landlord’s obligation to refund such amounts for any portion of the Term of this Lease shall survive the termination of this Lease even though determination of such amounts may not be made until after such termination.

D. To the extent that Real Estate Taxes for the Property shall be payable to the taxing authority in installments for periods less than a Tax Year, the foregoing statement shall be rendered and payments made on account of such installments with respect to such periods rather than with respect to such full Tax Year.

E. No decrease in Real Estate Taxes for the Property with respect to any Tax Year shall result in a reduction of the Fixed Rent payable by Tenant.

2.9 Electricity Charge

Tenant shall initially pay $1.50 per rentable square foot per year for the estimated cost of electricity for lights and outlets within the Premises (subject to adjustment pursuant to Section 2.7(C)), payable in equal monthly installments with the Fixed Rent and subject to the reconciliation process set forth in Section 2.7(B). The actual cost of Tenant’s share of electricity within the Premises shall be included in the annual Operating Statement along with Tenant’s Proportionate Share of common area electricity. Tenant shall not exceed electrical usage of 6.5 xxxxx per square foot included in the Premises.

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2.10 Due Date of Additional Payments; No Offsets

Except as otherwise specifically provided herein, any sum, amount, item or charge designated or considered as additional rent in this Lease shall be paid by Tenant to Landlord on or before the tenth (10th) business day after Landlord notifies Tenant of the amount payable. Any such notice shall specify in reasonable detail the basis of such additional rent. Additional rent shall be paid by Tenant to Landlord without offset or deduction.

2.11 Late Payment of Rent

If any installment of Fixed Rent or payment of additional rent is paid after the date the same was due, it shall bear interest from the due date at the rate published as the “prime rate” in The Wall Street Journal, as it may be adjusted from time to time, plus six percent (6%) per annum, but in no event more than the maximum rate of interest allowed by law, the payment of which shall be additional rent. For any installment of Fixed Rent or additional rent paid after the date the same was due, Tenant shall pay to Landlord, as additional rent, an amount equal to five percent (5%) of the total amount of delinquent rent (Fixed Rent plus additional rent) to offset Landlord’s administrative expenses resulting from Tenant’s delinquent payment.

2.12 Renewal Option

A. Provided that (i) a default as described in Section 7.1 of the Lease shall not have occurred and be continuing on the day on which Tenant purports to exercise the Renewal Option (defined below) or on the first day of the applicable Renewal Term (as defined below), and (ii) the Tenant named herein or a Tenant Affiliate is actually occupying at least 80% of the Premises as of each of said dates, Tenant shall have the option (“Renewal Option”) to renew the Term of this Lease for one (1) additional periods of three (3) years (the “Renewal Term”), unless sooner terminated as provided in this Lease, subject to all the terms of this Lease except for the change in Fixed Rent as provided below and there shall be no further Renewal Options.

B. Tenant shall exercise the Renewal Option, if at all, by giving written notice (“Notice to Renew”) of exercise to Landlord no later than nine (9) months prior to expiration of the Term. If Tenant fails to give such notice to Landlord within such time, Tenant shall be deemed to have waived the right to exercise the Renewal Option. Upon Tenant’s exercise of each Renewal Option, the Term shall be deemed to include the applicable Renewal Term.

C. The annual Fixed Rent payable during each Renewal Term shall be the fair market rent for comparable first class office space in effect in the 128 West office market on the commencement date of the applicable Renewal Term (the “Fair Market Rent”). The determination of Fair Market Rent (whether such determination is made by Landlord and/or Tenant or the brokers referenced herein) shall take into account all relevant factors such as (but not limited to) the rental rate currently charged by Landlord for space at the Property, the term of the lease, the base year for operating expenses and taxes, and brokerage commissions. The Fair Market Rent shall be determined as follows:

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(1) Within fifteen (15) calendar days after receipt of a Notice to Renew, Landlord shall furnish Tenant with Landlord’s estimate of Fair Market Rent (“Landlord’s Rent Estimate”).

(2) Within fifteen (15) calendar days after receipt of Landlord’s Rent Estimate, Tenant shall respond and specify whether and the extent to which Tenant disputes Landlord’s Rent Estimate.

(3) If Tenant disputes Landlord’s Rent Estimate, Tenant and Landlord shall negotiate in good faith for an additional thirty (30) calendar days to reach agreement on the Fair Market Rent.

(4) If Tenant and Landlord shall not have reached agreement as to the Fair Market Rent after such additional thirty (30) calendar days, Landlord and Tenant, within ten (10) calendar days after the expiration of such thirty (30) calendar day period, shall each select a real estate broker affiliated with a major Boston commercial real estate brokerage firm and having at least fifteen (15) years’ experience in the field with office properties similar to the Building in the Boston area to determine the Fair Market Rent. The two selected brokers shall within fourteen (14) calendar days appoint a third broker having the qualifications described above (the “Third Broker”). Each party shall pay the fees and expenses of the broker it selected and the fees and expenses of the Third Broker shall be borne equally by both parties.

(5) Within thirty (30) calendar days after the selection of the Third Broker, the brokers shall determine the Fair Market Rent. In the event that the brokers have not agreed upon the Fair Market Rent within such thirty (30) day period, each broker shall simultaneously deliver, within ten (10) calendar days thereafter, a written appraisal of the Fair Market Rent to Landlord and Tenant, and the Fair Market Rent shall be the average of the two closest appraisals.

(6) If Landlord or Tenant shall have failed to designate a broker within the time period provided therefor above, then the broker which has been designated, whether by Landlord or Tenant, shall alone make the determination of the Fair Market Rent. If Tenant and Landlord have both designated brokers but the two brokers so designated do not agree upon and designate the third broker willing so to act within the time period provided therefor above, the Tenant, the Landlord or either broker previously designated may request the Greater Boston Real Estate Board, Inc. to designate the third broker willing so to act and a broker so appointed shall, for all purposes, have the same standing and powers as though such broker had been seasonably appointed by the brokers first appointed. In case of the inability or refusal to serve of any person designated as a broker, or in case any broker for any reason ceases to be such, a broker to fill such vacancy shall be appointed by the Tenant, the Landlord, the broker first appointed or the said Greater Boston Real Estate Board, Inc., as the case may be, whichever made the original appointment.

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ARTICLE III

CONSTRUCTION

3.1 Premises As Is

THE PREMISES ARE LEASED “AS IS” AND “WHERE IS” AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTY WHATSOEVER, INCLUDING ANY WARRANTY OF MERCHANTABILITY, HABITABILITY OR FITNESS FOR INTENDED USE.

3.2 Landlord’s Work

Landlord shall prepare the Premises for Tenant’s use by painting and re-carpeting the Premises with building standard materials and finishes (“Landlord’s Work”). Notwithstanding anything to the contrary, Tenant shall be responsible for all furniture, tel/data wiring, security, other specialty items for the Premises (including dedicated HVAC units, if any) and any other improvements not part of Landlord’s Work at Tenant’s sole cost and expense.

3.3 General Provisions Applicable to Construction

All construction work required or permitted by this Lease, whether by Landlord or Tenant, shall be done in a good and workmanlike manner and in compliance with all applicable laws and all lawful ordinances, regulations and orders of governmental authority and insurers of the Property. Each party may inspect the work of the other at reasonable times and shall promptly give notice of observed defects.

3.4 Liens

Tenant will not permit any mechanic’s lien or other liens to be placed upon the Premises or the Property as a result of any materials or labor ordered by Tenant or any of Tenant’s agents, officers, or employees. If such a lien is filed, then within five (5) days after Landlord has delivered notice to Tenant, Tenant must either pay the amount of the lien or diligently contest such lien and deliver to Landlord a bond or other security satisfactory to Landlord. If Tenant fails to comply with the foregoing provisions of this Section 3.4, Landlord may exercise its self-help rights set forth in Section 8.6 to discharge or bond over the lien at Tenant’s sole cost and expense in any manner deemed appropriate by Landlord in its sole discretion.

ARTICLE IV

LANDLORD’S COVENANTS; INTERRUPTIONS AND DELAYS

Landlord covenants:

4.1 Services Furnished by Landlord

To furnish, through Landlord’s employees or independent contractors, services, utilities, facilities and supplies set forth in Exhibit D equal in quality to those customarily provided by landlords in similar office buildings in the vicinity of the Building.

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4.2 Additional Services Available to Tenant

To furnish, through Landlord’s employees or independent contractors, at Tenant’s expense, reasonable additional building operation services which are usual and customary additional services in similar office buildings in the vicinity of the Building upon reasonable advance request of Tenant at reasonable, equitable market rates from time to time established by Landlord.

4.3 Roof, Exterior Wall, Floor Slab and Common Facility Repair

Except as otherwise provided in ARTICLE VI, to make such repairs to the roof, exterior walls, other structural components, floor slabs, exterior glass (except as set forth in Section 5.2) and common areas and facilities including all utilities and elevators, of the Property as may be necessary to keep them in good order, repair and condition, the expense of which shall be charged in accordance with Section 2.7.

4.4 Quiet Enjoyment

That Tenant on paying the Fixed Rent and additional rent and performing the obligations of Tenant in this Lease shall peacefully and quietly have, hold and enjoy the Premises without interference from Landlord, or persons claiming by, through or under Landlord, subject to all of the terms and provisions hereof.

4.5 Interruptions and Delays in Service and Repairs, etc.

Landlord shall not be liable to Tenant for any compensation or reduction of rent by reason of inconvenience or annoyance or for loss of business arising from the necessity of Landlord or its agents’ entering the Premises for any of the purposes in this Lease authorized, or for repairing the Premises or any portion of the Building however the necessity may occur. In case Landlord is prevented or delayed from making any repairs, alterations or improvements, or furnishing any services or performing any other covenant or duty to be performed on Landlord’s part, by reason of any cause reasonably beyond Landlord’s control, Landlord shall not be liable to Tenant therefor, nor except as expressly otherwise provided in this Section 4.5 or Section 6.1 shall Tenant be entitled to any abatement or reduction of rent by reason thereof, nor shall the same give rise to a claim in Tenant’s favor that such failure constitutes actual or constructive, total or partial, eviction from the Premises.

Landlord reserves the right to stop any service or utility system, when necessary by reason of accident or emergency, or until necessary repairs have been completed; provided, however, that in each instance of stoppage Landlord shall exercise reasonable diligence to eliminate the cause thereof. Except in case of emergency repairs, Landlord will give Tenant reasonable advance notice of any contemplated stoppage and will use reasonable efforts to avoid unnecessary inconvenience to Tenant by reason thereof.

Notwithstanding anything to the contrary contained herein, if: (i) Landlord ceases to furnish any service in the Building for a period in excess of five (5) consecutive days after Tenant notifies Landlord of such cessation (the “Interruption Notice”); (ii) such cessation results from an act or omission of Landlord; (iii) the restoration of such service is within the reasonable

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control of Landlord; and (iv) as a result of such cessation, the Premises, or a material portion thereof, is rendered untenantable and Tenant in fact ceases to use the Premises, or a material portion thereof (each such cessation, a “Material Service Interruption”), then Tenant, as its sole remedy, shall be entitled to receive an abatement of Fixed Rent and additional rent during the period beginning on the sixth (6th) consecutive day after Landlord’s receipt of the Interruption Notice and ending on the day when the service in question has been restored. In the event the entire Premises has not been rendered untenantable by the Material Service Interruption, the amount of abatement that Tenant is entitled to receive shall be prorated based upon the percentage of the Premises so rendered untenantable and not used by Tenant.

4.6 Payment of Legal Expenses

To pay all reasonable costs, counsel and other fees incurred by Tenant in connection with the successful enforcement by Tenant of any obligations of Landlord under this Lease.

4.7 Landlord to Maintain Insurance; Waiver of Subrogation

Landlord shall procure and maintain the following:

(a) Property insurance “the equivalent of causes of loss – special form” on the Property. Landlord shall not be obligated to insure any furniture, equipment, trade fixtures, machinery, goods, or supplies which Tenant may keep or maintain in the Premises or any alteration, addition, or improvement which Tenant may make upon the Premises. In addition, Landlord may elect to secure and maintain rental income insurance. If the annual cost to Landlord for such property or rental income insurance exceeds the standard rates because of the nature of Tenant’s operations, Tenant shall, upon receipt of appropriate invoices, reimburse Landlord for such increased cost.

(b) Commercial general liability insurance, which shall be in addition to, and not in lieu of, insurance required to be maintained by Tenant. Tenant shall not be included as an additional insured on any policy of liability insurance maintained by Landlord.

(c) Landlord waives any and all rights of recovery against Tenant for or arising out of damage to, or destruction of the Premises to the extent (i) that Landlord’s property insurance policies then in force insure against such damage or destruction and permit such waiver and only to the extent of insurance proceeds actually received by Landlord for such damage or destruction; or (ii) such damage or destruction would have been covered by insurance proceeds had Landlord maintained the insurance required hereunder.

(d) Landlord will not be responsible for or liable to Tenant for any loss or damage that may be occasioned by or through the acts or omissions of persons occupying adjoining premises or any part of the premises adjacent to or connected with the Premises or any part of the Building or for any loss or damage resulting to Tenant or its property from burst, stopped or leaking water, gas, sewer or steam pipes or falling plaster, or electrical wiring or for any damage or loss of property within the Premises from any causes whatsoever, including but not limited to theft, and/or acts or threatened acts of terrorism, damage or injury due to mold, excepting only losses or damages resulting from the gross negligence or willful misconduct of Landlord. Landlord will not be liable under any circumstances to Tenant for any incidental or consequential damages.

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(e) Landlord, its agents, servants, employees, invitees, or contractors (each an “Indemnified Party”) shall not be liable to Tenant and Tenant hereby waives all claims against each Indemnified Party for any injury to or death of any person or damage to or destruction of property in or about the Premises or the Property by or from any cause whatsoever, including, without limitation, gas, fire, oil, electricity or leakage of any character from the roof, walls, basement or other portion of the Premises or the Property, but excluding, however, the gross negligence or willful misconduct of any Indemnified Party of which gross negligence or willful misconduct Landlord has knowledge and reasonable time to correct. Except as to injury to persons or damage to property to the extent caused by the gross negligence or willful misconduct of an Indemnified Party, Tenant shall indemnify, defend and hold each Indemnified Party harmless from and against any and all expenses, including reasonable attorneys’ fees, in connection therewith, arising out of any injury to or death of any person or damage to or destruction of property occurring in, on or about the Premises, or any part thereof, from any cause whatsoever.

(f) To the maximum extent permitted by law, Tenant shall indemnify, defend and hold harmless the Indemnified Parties (including reasonable attorneys’ fees, investigation costs and remediation costs) from and against any and all claims, demands, liabilities, damages, judgments, fines and penalties which in any manner whatsoever arise out of or are in any manner related to: (i) Tenant’s failure to maintain the Premises pursuant to Section 5.2 of this Lease; or (ii) the presence of mold in the Premises or Building to the extent caused by, contributed to, or allowed by Tenant.

(g) Except for damages incurred by Landlord pursuant to Section 8.15 of this Lease, Tenant will not be liable under any circumstances to Landlord for any incidental or consequential damages.

ARTICLE V

TENANT’S COVENANTS

Tenant covenants during the Term and such further time as Tenant occupies any part of the Premises:

5.1 Payments

To pay when due all Fixed Rent and additional rent and all charges for utility services rendered to the Premises and, as further additional rent, all charges for additional services and utilities rendered pursuant to Section 4.2.

5.2 Repair and Yield Up

Except as otherwise provided in ARTICLE VI and Section 4.3, at its sole cost and expense, to keep the Premises in good order, repair and condition, and all glass in windows

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(except uninsured glass in exterior walls of the Building unless the damage thereto is attributable to Tenant’s negligence or misuse) and doors of the Premises whole and in good condition with glass of the same quality as that injured or broken, damage by fire and other casualty and reasonable wear only excepted, and at the expiration or termination of this Lease peaceably to yield up the Premises and all alterations and additions thereto in good order, repair and condition, damage by fire and other casualty excepted, first removing all goods and effects of Tenant and, if identified by Landlord for removal at the time that Tenant requested Landlord’s approval, all alterations and additions made by Tenant and all partitions, and repairing any damage caused by such removal and restoring the Premises and leaving them clean and neat and in reasonably tenantable condition for office use.

5.3 Use

To use and occupy the Premises for the Permitted Uses, and not to injure or deface the Premises, or the Property, nor to permit in the Premises any auction sale, or inflammable fluids or chemicals (except that Tenant may keep and use in the Premises normal office supplies in full compliance with law), nor to permit any nuisance, or the emission from the Premises of any objectionable noise or odor, nor to use or devote the Premises or any part thereof for any purpose other than the Permitted Uses, nor any use thereof which is contrary to law or ordinance or liable to invalidate or increase the premiums for any insurance on the Building or liable to render necessary any alteration or addition to the Building.

5.4 Obstructions; Items Visible from Exterior; Rules and Regulations; Signs

Not to obstruct in any manner any portion of the Building not hereby leased or any portion thereof or of the Property; not without prior consent of Landlord to permit the painting or placing of any signs, curtains, blinds, shades, awnings, aerials or flagpoles, or the like, visible from outside the Premises; and to comply with Landlord’s Rules and Regulations set forth in Exhibit E and all other reasonable Rules and Regulations now or hereafter made by Landlord, of which Tenant has been given notice, for the care and use of the Building and Lot and their facilities and approaches; Landlord shall not be liable to Tenant for the failure of other occupants of the Building to conform to such Rules and Regulations, but Landlord shall use reasonable efforts to enforce the same in a non-discriminatory manner against all tenants and occupants of the Building. Tenant’s name shall be displayed on the tenant directory within the Building and on the doors to the Premises in accordance with Landlord’s standard graphics or such other graphics as Landlord shall approve in its sole discretion. Except on such directory and doors to the Premises and on floors of the Building occupied solely by Tenant, no other signs for Tenant on the interior of the Building will be permitted without Landlord’s consent which will not be unreasonably withheld.

5.5 Safety Appliances; Hazardous Materials

To keep the Premises equipped with all safety appliances required by law or ordinance or any other regulation of any public authority because of any use made by Tenant or its employees, agents, officers, customers or clients other than normal office use, and to procure all licenses and permits so required because of such use and, if requested by Landlord, to do any work so required because of such use, it being understood that the foregoing provisions shall not be construed to broaden in any way Tenant’s Permitted Uses.

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Tenant shall not cause, suffer or allow any hazardous materials to be used, generated, stored or disposed of on, under or about the Premises except in accordance with applicable law. Tenant shall defend, indemnify and save harmless Landlord from and against any injuries, claims, accidents, damages, liabilities and expenses and any contamination of or injury to the Premises or the Building or the Lot (including reasonable counsel fees) arising out of any breach of Tenant’s obligations under this Section 5.5 or any storage, use, disposal or release of the foregoing materials by Tenant.

Tenant shall provide Landlord on February 1 and August 1 of each year of the Term with a list of the names and quantities of all hazardous materials generated, stored or used at the Premises (other than reasonable quantities of cleaning and office supplies). Material Safety Data Sheets shall be provided for all such substances. Storage of all hazardous materials shall be in accordance with applicable federal, state and local laws, regulations and ordinances. Tenant shall prepare and follow a spill prevention and countermeasure plan for such substances. Transfer and mixing of hazardous materials shall be performed in a designated area designed and operated to prevent spilling, leakage or runoff from escaping from the Premises. Tenant shall comply with all applicable OSHA rules applicable to its business and the handling of hazardous materials.

Tenant shall immediately notify Landlord both by telephone and in writing of any spill or unauthorized discharge or release of hazardous materials. At the expiration or termination of this Lease, Tenant shall yield up the Premises free of all hazardous materials and contaminants of any kind resulting from Tenant’s use of the Premises or any action of Tenant, its employees, agents, contractors and invitees.

For purposes of this paragraph the term hazardous material shall mean, (i) “hazardous substances” or “toxic substances” or “oil” as those terms are defined by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), 42 U.S.C. § 9601, et seq., or the Hazardous Materials Transportation Act, 49 U.S.C. § 1801 or the Massachusetts Oil and Hazardous Material Release Prevention and Response Act, M.G.L. c. 21E; (ii) “hazardous wastes,” as that term is defined by the Resource Conservation and Recovery Act (RCRA), 42 U.S.C. § 6901, et seq.; (iii) any pollutant or contaminant or hazardous, dangerous, or toxic chemicals, materials, or substances within the meaning of any other applicable federal, state, or local law, regulation, ordinance, or requirement relating to or imposing liability or standards of conduct concerning any hazardous, toxic, or dangerous waste substance or material; (iv) any radioactive material, including any source, special nuclear or by-product material as defined at 42 U.S.C. § 2011, et seq.; (v) asbestos in any form or condition; and (vi) polychlorinated biphenyls (PCBs) or substances or compounds containing PCBs.

5.6 Assignment; Sublease

(a) Without prior written consent of Landlord, not to assign, mortgage, pledge or otherwise transfer (directly or indirectly) this Lease or its rights hereunder, or to make any sublease, or to permit occupancy of the Premises or any part thereof by anyone other than

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Tenant, except that Tenant may assign this Lease without Landlord’s consent (but with at least thirty (30) days’ prior written notice to Landlord) to (i) an entity controlling, controlled by or under common control with Tenant, or (ii) an entity purchasing all of Tenant’s business, assets and liabilities, or (iii) an entity that succeeds to the interests of Tenant under this Lease by way of merger, consolidation, or corporate reorganization (each entity described in clauses (i), (ii) and (iii) of this sentence, a “Tenant Affiliate”), only if such Tenant Affiliate has a net worth at least equal to that of Tenant as of the date of this Lease. In connection with any proposed assignment or subletting, Tenant shall submit to Landlord in writing (i) the name of the proposed assignee or sublessee, (ii) such information as to its financial responsibility and standing as Landlord may reasonably require, (iii) all of the terms and provisions upon which the proposed assignment or subletting is to be made; and (iv) the nature of its business and proposed use of the Premises. Tenant shall supply such additional information as Landlord reasonably requests.

(b) Tenant shall not offer to make or enter into negotiations with respect to an assignment or sublease (i) to any tenant in the Building or the adjacent building at 000 Xxxxxx Xxxxxx, Xxxxxxx, Xxxxxxxxxxxxx, (ii) to any party with whom, to Tenant’s knowledge (after first consulting with Landlord), Landlord is then negotiating (or with which it has negotiated in the last six months) with respect to space in the Building or such adjacent building, (iii) to any party which would be of such type, character or condition as to be inappropriate as a tenant for a comparable office building, or (iv) unless the aggregate rent payable to Tenant equals or exceeds the then prevailing market rate rent for assigning or subleasing (as applicable) space comparable to the Premises in comparable office buildings in the Boston Metropolitan area.

(c) If Tenant intends to assign this Lease or sublease all or any part of the Premises, it shall notify Landlord thereof together with identification of the space involved and the contemplated economic terms, and Landlord shall have the option, exercisable by notice to Tenant (a “Termination Notice”) given within thirty (30) days after receipt of any such notification and information, to terminate this Lease as of a date specified in such Termination Notice, which date shall not be less than thirty (30) or more than ninety (90) days after the date of such Termination Notice. If Tenant does not thereafter notify Landlord within two (2) business days following Tenant’s receipt of such Termination Notice that Tenant no longer intends to assign this Lease or sublease all or any part of the Premises, as applicable, Landlord may exercise its right to terminate this Lease pursuant to the applicable provisions of this paragraph. If Tenant does so notify Landlord, then Landlord’s Termination Notice shall be deemed waived and of no further force or effect, and this Lease shall continue in accordance with its terms. In no event shall Landlord’s right of recapture apply in case of a sublease or assignment to a Tenant Affiliate.

(d) If Landlord does not exercise its right to terminate this Lease pursuant to the foregoing provisions, Landlord shall not unreasonably withhold or delay its consent to an assignment or subletting consistent with the information supplied by Tenant in its notification, provided that the terms and provisions of such assignment or subletting shall specifically make applicable to the assignee or sublessee all of the provisions of this Section 5.6 so that Landlord shall have against the assignee or sublessee all rights with respect to any further assignment and subletting which are set forth herein; no assignment or subletting shall affect the continuing primary liability of Tenant (which, following assignment, shall be joint and several with the assignee); no consent to any of the foregoing in a specific instance shall operate as a waiver in a

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subsequent instance; and no assignment shall be binding upon Landlord or any of Landlord’s mortgagees, unless Tenant shall deliver to Landlord an instrument in recordable form which contains a covenant of assumption by the assignee running to Landlord and all persons claiming by, through or under Landlord and Landlord and all of its mortgagees decide, in their sole discretion, to accept such assumption, but the failure or refusal of the assignee to execute such instrument of assumption shall not release or discharge assignee from its liability as Tenant hereunder. Should Landlord exercise its right to terminate this Lease to only a portion of the Premises, Tenant shall be obligated to reimburse Landlord for the cost of demising walls, doors and partitions in compliance with applicable codes and at Building standard finishes.

(e) It shall be reasonable for Landlord to refuse consent to any assignment or sublease to any governmental agency or to any entity which by reputation or expected use is not comparable to other types of tenants in the Building or to an entity which is a tenant of the Property or the adjacent building at 000 Xxxxxx Xxxxxx, Xxxxxxx, Xxxxxxxxxxxxx, or to an entity which does not have, in Landlord’s sole good faith determination, a satisfactory financial condition in relation to the obligations to be assumed under the assignment or sublease or if the assignment or sublease would cause Landlord to be in violation or any laws or any other lease, mortgage or other agreement. If Tenant disputes Landlord’s decision to deny consent to an assignment or sublease, Tenant’s sole remedy shall be to seek injunctive relief.

Without limitation of the rights of Landlord hereunder, if there is an assignment of this Lease by Tenant or a subletting of the Premises by Tenant to any person or entity other than a Tenant Affiliate at a rent which, in either case, exceeds the rent payable hereunder by Tenant, Tenant shall pay to Landlord, as additional rent, fifty percent (50%) of such excess rent (after deducting therefrom any reasonable costs incurred by Tenant for brokerage commissions, legal fees or fit up work or allowances in connection with such assignment or subletting). For purposes of this Section 5.6, the term “rent” shall mean all Fixed Rent, additional rent or other payment and/or consideration payable to Tenant.

The term “subletting” or “sublease” shall not only mean a sublease, but also any license or concession agreement or agreement for the use, occupancy or utilization of the Premises. Tenant shall reimburse Landlord for its reasonable legal and other expenses in connection with any request for consent under this Section.

5.7 Indemnity; Insurance; Waiver of Subrogation

A. To defend with counsel first reasonably approved by Landlord, save harmless, and indemnify Landlord, its agents and employees, from any liability for injury, loss, accident or damage to any person or property, and from any claims, actions, proceedings and expenses and costs in connection therewith (including without limitation reasonable counsel fees), (i) arising from (a) the omission, fault, willful act, negligence or other misconduct of Tenant, its employees, agents or invitees, or (b) any use made or thing done or occurring on the Premises not due to the negligence or willful misconduct of Landlord or its agents or employees, or (ii) resulting from the failure of Tenant to perform and discharge its covenants and obligations under this Lease;

B. In the event that Tenant fails to provide evidence of insurance required to be provided by Tenant in this Lease in accordance with Section 5.7E, Landlord shall be authorized (but not required) to procure such coverage in the amount stated with all costs thereof to be chargeable to Tenant and payable upon written invoice thereof.

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C. The limits of insurance required by this Lease, or as carried by Tenant, shall not limit the liability of Tenant or relieve Tenant of any obligation thereunder, except to the extent provided for under Section 4.7(b) of this Lease. Any deductibles selected by Tenant shall be the sole responsibility of Tenant.

D. Tenant, at Tenant’s expense, agrees to keep in force during the Term of this Lease:

(i) Commercial general liability insurance which insures against claims for bodily injury, personal injury, advertising injury, and property damage based upon, involving, or arising out of the use, occupancy, or maintenance of the Premises and the Property. Such insurance shall afford, at a minimum, the following limits:

Each Occurrence		$1,000,000
General Aggregate		$2,000,000
Products/Completed Operations Aggregate		$1,000,000
Personal and Advertising Injury Liability		$1,000,000
Fire Damage Legal Liability		$100,000
Medical Payments		$5,000

Any general aggregate limit shall apply on a per location basis. Tenant’s commercial general liability insurance shall include Waltham Winter Street 880 LP and, Waltham Winter Street 890 LP and, Clarion Partners, LLC, and CB Xxxxxxx Xxxxx – N.E. Partners, Limited Partnership, and their trustees, officers, directors, members, agents, and employees, Landlord’s mortgagees, Landlord’s property manager, Landlord’s representatives and any other party reasonably requested by Landlord as additional insureds (the “Additional Insured Parties”). This coverage shall be written on the most current ISO CGL form (or its equivalent), shall include contractual liability, premises-operations and products-completed operations and shall contain an exception to any pollution exclusion which insures damage or injury arising out of heat, smoke, or fumes from a hostile fire. Such insurance shall be written on an occurrence basis and contain a standard separation of insureds provision.

(ii) Business automobile liability insurance covering owned, hired and non-owned vehicles with minimum limits of $1,000,000 combined single limit per occurrence.

(iii) Workers’ compensation insurance in accordance with the laws of the state in which the Premises are located with employer’s liability insurance in an amount not less than $1,000,000.

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(iv) Umbrella/excess liability insurance, on an occurrence basis, that applies excess of the required commercial general liability, business automobile liability, and employer’s liability policies with the following minimum limits:

Each Occurrence                                 $5,000,000

Annual Aggregate                               $5,000,000

Umbrella/Excess liability policies shall contain an endorsement stating that any entity qualifying as an additional insured on the insurance stated in the Schedule of Underlying Insurance shall be an additional insured on the umbrella/excess liability policies, and that they apply immediately upon exhaustion of the insurance stated in the Schedule of Underlying Insurance as respects the coverage afforded to any additional insured. The umbrella/excess liability policies shall also provide that they apply before any other insurance, whether primary, excess, contingent or on any other basis, available to an additional insured on which the additional insured is a named insured (which shall include any self-insurance), and that the insurer will not seek contribution from such insurance.

(v) Property insurance “the equivalent of causes of loss – special form” including flood, earthquake, windstorm, theft, sprinkler leakage and boiler and machinery coverage on all of Tenant’s trade fixtures, furniture, inventory and other personal property in the Premises, and on any alterations, additions, or improvements made by Tenant upon the Premises all for the full replacement cost thereof. Tenant shall use the proceeds from such insurance for the replacement of trade fixtures, furniture, inventory and other personal property and for the restoration of Tenant’s improvements, alterations, and additions to the Premises. Landlord shall be named as loss payee with respect to alterations, additions, or improvements of the Premises where the Tenant cannot remove at the end of the lease term wherein ownership then reverts to the Landlord.

(vi) Business income and extra expense insurance with limits not less than one hundred percent (100%) of all rent and charges payable by Tenant under this Lease for a period of twelve (12) months.

E. All policies required to be carried by Tenant hereunder shall be issued by an insurance company licensed or authorized to do business in the state in which the Property is located with a rating of at least “A-: X” or better as set forth in the most current issue of Best’s Insurance Reports, unless otherwise approved by Landlord. Tenant shall not do or permit anything to be done that would invalidate the insurance policies required herein. Liability insurance maintained by Tenant shall be primary coverage on behalf of the Additional Insured Parties and any policies of the Additional Insured Parties shall be non-contributory. Certificates of insurance, acceptable to Landlord, evidencing the existence and amount of each insurance policy required hereunder shall be delivered to Landlord prior to delivery or possession of the Premises and ten (10) days following each renewal date. Certificates of insurance shall evidence that the Additional Insured Parties are included as additional insureds on liability policies and that Landlord is included as loss payee on the property insurance with respect to alterations, additions, or improvements of the Premises where the Tenant cannot remove at the end of the lease term wherein ownership then reverts to the Landlord. Further, each policy shall contain provisions endeavoring to give Landlord and each of the other Additional Insured Parties at least thirty (30) days prior written notice of cancellation or non-renewal of coverage.

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F. In the event that Tenant fails to provide evidence of insurance required to be provided by Tenant in this Lease, prior to the Commencement Date and thereafter during the Term, within ten (10) days following Landlord’s request thereof, and thirty (30) days prior to the expiration of any such coverage, Landlord shall be authorized (but not required) to procure such coverage in the amount stated with all costs thereof to be chargeable to Tenant and payable upon written invoice thereof.

G. The limits of insurance required by this Lease, or as carried by Tenant, shall not limit the liability of Tenant or relieve Tenant of any obligation thereunder, except to the extent provided for under Section 4.7 above. Any deductibles selected by Tenant shall be the sole responsibility of Tenant.

H. Tenant insurance requirements stipulated in Section 5.7(D)(i) are based upon current industry standards. Landlord reserves the right to require additional coverage or to increase limits as industry standards change.

I. Should Tenant engage the services of any contractor to perform work in the Premises, Tenant shall ensure that such contractor carries commercial general liability, business automobile liability, umbrella/excess liability, worker’s compensation and employers liability coverages in substantially the same forms as required of the Tenant under this Lease and in amounts approved by landlord and/or landlord’s property manager. Contractor shall include Landlord and each of the other Additional Insured Parties as additional insureds on the liability policies required hereunder.

All policies required to be carried by any contractor shall be issued by and binding upon an insurance company licensed or authorized to do business in the state in which the Property is located with a rating of at least “A-: X” or better as set forth in the most current issue of Best’s Insurance Reports, unless otherwise approved by Landlord. Certificates of insurance, acceptable to Landlord, evidencing the existence and amount of each insurance policy required hereunder shall be delivered to Landlord prior to the commencement of any work in the Premises. Further, each policy will contain provisions giving Landlord and each of the other Additional Insured Parties with at least thirty (30) days’ prior written notice of any cancelation, non-renewal or material change in coverage. The above requirements shall apply equally to any subcontractor engaged by contractor.

J. Tenant waives any and all rights of recovery against Landlord for or arising out of damage to or destruction of any property of Tenant to the extent that Tenant’s property insurance policies then in force or the policies required by this Lease, whichever is broader, insure against such damage or destruction.

5.8 Personal Property at Tenant’s Risk

That notwithstanding anything to the contrary, all of the furnishings, fixtures, equipment, effects and property of every kind, nature and description of Tenant and all persons claiming by, through or under Tenant which, during the continuance of this Lease or any occupancy of the

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Premises by Tenant or anyone claiming under Tenant, may be on the Premises or elsewhere in the Building or on the Lot shall be at the sole risk and hazard of Tenant, and if the whole or any part thereof shall be destroyed or damaged by fire, water or otherwise, or by the leakage or bursting of water pipes, steam pipes, or other pipes, by theft or from any other cause, no part of said loss or damage is to be charged to or be borne by Landlord, except that Landlord shall in no event be indemnified or held harmless or exonerated from any liability to Tenant or to any person, for any injury, loss, damage or liability to the extent such indemnity, hold harmless or exoneration is prohibited by law.

5.9 Right of Entry

To permit Landlord and its agents after reasonable notice (which may be oral) except in the case of an emergency: to examine the Premises at reasonable times and, if Landlord shall so elect, to make any repairs or replacements Landlord may deem necessary; to remove, at Tenant’s expense, any alterations, additions, signs, curtains, blinds, shades, awnings, aerials, flagpoles, or the like not consented to in writing (where such consent is required under the terms of this Lease); and to show the Premises to prospective tenants and to prospective purchasers and mortgagees at all reasonable times. In exercising its rights under this paragraph, Landlord shall use reasonable efforts to avoid interference with Tenant’s business.

5.10 Floor Load; Prevention of Vibration and Noise

Not to place a load upon the Premises exceeding an average rate of eighty (80) pounds of live load per rentable square foot of floor area (partitions shall be considered as part of the live load); Landlord reserves the right to prescribe the weight and position of all safes, files and heavy equipment which Tenant desires to place in the Premises so as properly to distribute the weight thereof; Tenant’s business machines and mechanical equipment which cause vibration or noise that may be transmitted to the Building structure or to any other space in the Building shall be so installed, maintained and used by Tenant as to eliminate such vibration or noise.

5.11 Personal Property Taxes

To pay promptly when due all taxes which may be imposed upon personal property (including without limitation, fixtures and equipment) in the Premises to whomever assessed if failure to pay would result in a lien on the Property.

5.12 Payment of Legal Expenses

As additional rent, to pay all reasonable costs, counsel and other fees incurred by Landlord in connection with the successful enforcement by Landlord of any obligations of Tenant under this Lease.

5.13 Compliance with Insurance Regulations

Not to do or permit to be done any act or thing upon the Premises which will invalidate or be in conflict with the terms of the Massachusetts standard form of fire, boiler, sprinkler, water damage or other insurance policies covering the Building and the fixtures and property therein; Tenant shall, at its own expense, comply with all rules, regulations, and requirements of the

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National Board of Fire Underwriters or any state or other similar body having jurisdiction, and shall not knowingly do or permit anything to be done in or upon the Premises in a manner which increases the rate of fire insurance upon the Building or on any property or equipment located therein. If activity, use, or occupancy by Tenant, its employees, agents or invitees in or upon the Premises results in the increase in the rate of fire insurance upon the Building, Landlord shall xxxx Tenant for such excess and Tenant shall promptly pay such excess insurance costs. Notwithstanding the foregoing, such billing by Landlord and payment by Tenant shall not waive Landlord’s right to require such activity to cease.

ARTICLE VI

CASUALTY AND TAKING

6.1 Termination or Restoration; Rent Adjustment

If during the Term all or any substantial part of the Premises or the Building or the Lot are damaged materially by fire or other casualty or by action of public or other authority in consequence thereof, or are taken by eminent domain or Landlord receives compensable damage by reason of anything lawfully done in pursuance of public or other authority, this Lease shall terminate at Landlord’s election, which may be made notwithstanding Landlord’s entire interest may have been divested, by notice given to Tenant within forty-five (45) days after the date of casualty or taking specifying the effective date of termination. If this Lease is not so terminated by Landlord, Landlord shall provide to Tenant in writing within forty-five (45) days after the casualty or taking the estimate from a contractor engaged by Landlord of the cost of repair and when the Premises or the Common Areas of the Building, as the case may be, could be restored to proper condition for occupancy by Tenant. If such estimate is nine (9) months or more after the date of the casualty or taking, or if there is a taking of fifteen (15%) per cent or more of the area of the Premises or a taking of material portions of the Building or the Property providing access to the Premises or of a material portion of the parking areas and Tenant certifies to Landlord that the remainder of the Premises is insufficient for the operations of Tenant’s business, then Tenant may terminate this Lease by written notice to Landlord within twenty (20) days after receipt of such estimate or the date possession of the Premises is taken, as the case may be. The effective date of termination specified by either Landlord or Tenant shall not be less than fifteen (15) nor more than thirty (30) days after the date of notice of such termination. Unless terminated pursuant to the foregoing provisions, this Lease shall remain in full force and effect following any such damage or taking, subject, however, to the following provisions. If in any such case the Premises are rendered unfit for use and occupancy and this Lease is not so terminated, Landlord shall use due diligence (following the expiration of the period in which Landlord or Tenant may terminate this Lease pursuant to the foregoing provisions of this Section 6.1) to put the Premises, or in case of taking what may remain thereof (excluding in case of both casualty and taking any items installed or paid for by Tenant which Tenant may be required to remove), into proper condition for use and occupancy (in the case of a taking to the extent permitted by the net award of damages and in the case of a casualty, to the extent of the net insurance proceeds and any retained amount), and a just proportion of the Fixed Rent and additional rent according to the nature and extent of the injury shall be abated from the date of such casualty or taking until the Premises or such remainder shall have been put by Landlord in such condition; and in case of taking which permanently reduces the area of the Premises, a just

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proportion of the Fixed Rent and additional rent shall be abated for the remainder of the Term. In addition, if neither Landlord nor Tenant terminate this Lease as permitted above, and Landlord does not complete restoration of the Premises within 270 days after the date of the casualty or taking, Tenant shall have the right to terminate this Lease by written notice to Landlord.

6.2 Eminent Domain Award

Landlord reserves to itself any and all rights to receive awards made for damages to the Premises and Building and Lot and the leasehold hereby created, or any one or more of them, accruing by reason of exercise of eminent domain or by reason of anything lawfully done in pursuance of public or other authority. Tenant hereby releases and assigns to Landlord all Tenant’s rights to such awards, and covenants to deliver such further assignments and assurances thereof as Landlord may from to time request. Tenant hereby irrevocably designates and appoints Landlord as its attorney-in-fact to execute and deliver in Tenant’s name and on its behalf any such further assignments thereof. Notwithstanding the foregoing, Tenant shall be entitled to any damages for personal property of Tenant and for reasonable relocation expenses which are available to Tenant in a separate action or separate award.

6.3 Temporary Taking

In the event of taking of the Premises or any part thereof for temporary use, (i) this Lease shall be and remain unaffected thereby and rent shall not xxxxx, and (ii) Tenant shall be entitled to receive for itself such portion or portions of any award made for such use with respect to the period of the taking which is within the Term, provided that if such taking shall remain in force at the expiration or earlier termination of this Lease, Tenant shall then pay to Landlord a sum equal to the reasonable cost of performing Tenant’s obligations under Section 5.2 with respect to surrender of the Premises and upon such payment shall be excused from such obligations.

ARTICLE VII

DEFAULT

7.1 Events of Default

If any default, breach or failure of performance by Tenant of any agreement, covenant, condition, provision, or warranty contained herein continues, in cases of failure to pay Fixed Rent or additional rent or other payments required hereunder (i) within five (5) days after notice from Landlord to be given no more than two (2) times in any calendar year and otherwise (ii) on the date due, or in cases other than monetary defaults continuing for more than thirty (30) days after notice from Landlord and such additional time, if any, as is reasonably necessary to cure the default if the default is of such a nature that it cannot reasonably be cured in thirty (30) days provided Tenant commences to cure promptly and diligently pursues the cure to completion but in no case more than ninety (90) days after notice from Landlord; or if Tenant or any guarantor or any guarantors of any of Tenant’s obligations under this Lease is not paying its debts as such debts become due, becomes insolvent, files or has filed against it (and in the case of an involuntary petition such is not dismissed within 30 days after the filing) a petition under any chapter of the U.S. Bankruptcy Code (or any similar petition under any insolvency law of any

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jurisdiction), proposes any dissolution, liquidation, composition, financial reorganization or recapitalization with creditors, makes an assignment or trust mortgage for the benefit of creditors, or if a receiver, trustee, custodian or similar agent is appointed or takes possession with respect to any property or business of Tenant or such guarantor, then in any such case, whether or not the Term shall have begun, Landlord may immediately, or at any time while such default exists and without further notice, terminate this Lease by notice to Tenant, specifying the date on which this Lease shall terminate and this Lease shall come to an end on the date specified therein as fully and completely as if such date were the date herein originally fixed for the expiration of the Term, and Tenant shall then quit and surrender the Premises to Landlord, but Tenant shall remain liable as hereinafter provided.

7.2 Landlord’s Rights and Tenant’s Obligations after Termination

In the event that this Lease is terminated under any of the provisions contained in Section 7.1, Tenant covenants to pay forthwith to Landlord upon demand, as compensation, the excess of the total rent reserved for the residue of the Term over the fair market rental value of the Premises for said residue of the Term (after deduction of all anticipated expenses of reletting) discounted to present value determined by reference to The Wall Street Journal listing of “Treasury Bonds, Notes, and Bills” (representative of New York, based on transactions of $1,000,000 or more), of the yield to maturity on issues closest to the expiration of the Term of this Lease. In calculating the rent reserved there shall be included, in addition to the Fixed Rent and all additional rent, the value of all other considerations agreed to be paid or performed by Tenant for said residue. For purposes of clarification, Landlord shall not be obligated to wait for the original expiration of the Term of the Lease or until the Premises have been relet to exercise the foregoing remedy. Landlord may exercise such remedy immediately upon termination of the Lease, and Tenant shall be obligated to pay the applicable damages immediately upon Landlord’s demand. In no event shall Tenant be entitled to a credit if the excess of the fair market rental value of the Premises for the residue of the Term exceeds the total rent reserved for the residue of the Term.

Tenant further covenants as an additional and cumulative obligation after any such termination to pay punctually to Landlord all the sums and perform all the obligations which Tenant covenants in this Lease to pay and to perform in the same manner and to the same extent and at the same time as if this Lease had not been terminated. In calculating the amounts to be paid by Tenant under the foregoing covenant Tenant shall be credited with any amount paid to Landlord as compensation as in this Section 7.2 provided and also with the net proceeds of any rent obtained by Landlord by reletting the Premises, after deducting reasonable expenses in connection with such reletting, including, without limitation, repossession costs, brokerage commissions, fees for legal services and expenses of preparing the Premises for such reletting, it being agreed by Tenant that Landlord may (but shall have no obligation to) (i) relet the Premises or any part or parts thereof, for a term or terms which may, at Landlord’s option, be equal to or less than or exceed the period which would otherwise have constituted the balance of the Term and may grant such concessions and free rent as Landlord in its sole judgment considers advisable or necessary to relet the same, and (ii) make such alterations, repairs and decorations in the Premises as Landlord in its sole judgment considers advisable or necessary to relet the same, and no action of Landlord in accordance with the foregoing or failure to relet or to collect rent under reletting shall operate or be construed to release or reduce Tenant’s liability as aforesaid.

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In no event shall Tenant be entitled to a reletting credit that exceeds the amount due to Landlord under this Section 7.2.

In lieu of any other damages or indemnity and in lieu of full recovery by Landlord of all sums payable under all the foregoing provisions of this Section 7.2, Landlord may, by written notice to Tenant, at any time after this Lease is terminated under any of the provisions contained in Section 7.1 or is otherwise terminated for breach of any obligation of Tenant and before such full recovery, elect to recover, and Tenant shall thereupon pay, as liquidated damages, an amount equal to the aggregate of the Fixed Rent and additional rent accrued under Sections 2.6, 2.7 and 2.8 in the twelve (12) month period immediately prior to such termination plus the amount of Fixed Rent and additional rent of any kind accrued and unpaid at the time of termination and less the amount of any recovery by Landlord under the foregoing provisions of this Section 7.2 up to the time of payment of such liquidated damages. Landlord and Tenant acknowledge that: (i) it would be impossible or impracticable to fix the actual damages suffered by Landlord as a result of termination of this Lease pursuant to this Section 7.2; (ii) the amount of the liquidated damages represents a fair and reasonable compensation to Landlord for such damages; and (iii) the liquidated damages set forth in this Section 7.2 do not constitute a penalty.

Nothing contained in this Lease shall limit or prejudice the right of Landlord to prove for and obtain in proceedings for bankruptcy or insolvency by reason of the termination of this Lease, an amount equal to the maximum allowed by any statute or rule of law in effect at the time when, and governing the proceedings in which, the damages are to be proved.

ARTICLE VIII

MISCELLANEOUS

8.1 Notice of Lease; Consent and Approval; Notices; Bind and Inure

The titles of the Articles are for convenience only and are not to be considered in construing this Lease. Tenant agrees not to record this Lease, but upon request of either party both parties shall execute and deliver a notice of this Lease pursuant to M.G.L. c. 183 § 4, and if this Lease is terminated before the Term expires, an instrument in such form acknowledging the date of termination. Whenever any notice, approval, consent, request or election is given or made pursuant to this Lease it shall be in writing. Communications and payments shall be addressed if to Landlord at Landlord’s Original Address or at such other address as may have been specified by prior notice to Tenant, and if to Tenant, at Tenant’s Original Address or after the Commencement Date at the Premises, with a copy to Xxxxx Xxxx LLP, 000 Xxxxxxx Xxxxxxxxx, Xxxxxx, XX 00000, Attn: Xxxxxx X. Xxxxxxxx, Esq., or at such other place as may have been specified by prior notice to Landlord. Any communication so addressed shall be deemed duly given upon delivery in hand or one (1) business day after it is sent by overnight mail or by regularly recognized overnight courier which supplies a receipt therefor, or two (2) business days after it is mailed by registered or certified mail, return receipt requested. If Landlord by notice to Tenant at any time designates some other person to receive payments or notices, all payments or notices thereafter by Tenant shall be paid or given to the person designated until notice to the contrary is received by Tenant from Landlord. The obligations of this Lease shall run with the land, and this Lease shall be binding upon and inure to the benefit of the parties hereto and their respective successors and assigns, subject to the limitations set forth in Section 0.

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8.2 Landlord’s Failure to Enforce

The failure of Landlord to seek redress for violation of, or to insist upon strict performance of, any covenant or condition of this Lease, shall not be deemed a waiver of such violation nor prevent a subsequent act which would have originally constituted a violation, from having all the force and effect of an original violation. The receipt by Landlord of Fixed Rent or additional rent with knowledge of the breach of any covenant of this Lease shall not be deemed a waiver of such breach. No provision of this Lease shall be deemed to have been waived by Landlord or Tenant unless such waiver is in writing signed by the party to be charged. No consent or waiver, express or implied, by Landlord or Tenant, to or of any breach of any agreement or duty shall be construed as a waiver or consent to or of any other breach of the same or any other agreement or duty.

8.3 Acceptance of Partial Payments of Rent; Delivery of Keys

No acceptance by Landlord of a lesser sum than the Fixed Rent and additional rent then due shall be deemed to be other than on account of the earliest installment of such rent due, nor shall any endorsement or statement on any check or any letter accompanying any check or payment as rent be deemed an accord and satisfaction, and Landlord may accept such check or payment without prejudice to Landlord’s right to recover the balance of such installment or pursue any other remedy in this Lease provided. The delivery of keys to any employee of Landlord or to Landlord’s agent or any employee or other party thereof shall not operate as a termination of this Lease or surrender of the Premises.

8.4 Cumulative Remedies

The specific remedies to which Landlord may resort under the terms of this Lease are cumulative and are not intended to be exclusive of any other remedies or means of redress to which it may be lawfully entitled in case of any breach or threatened breach by Tenant of any provisions of this Lease. In addition to other remedies provided in this Lease, Landlord shall be entitled to the restraint by injunction of the violation or attempted or threatened violation of any of the covenants, conditions or provisions of this Lease or to a decree compelling specific performance of any such covenants, conditions or provisions.

8.5 Partial Invalidity

If any term of this Lease, or the application thereof to any person or circumstances, shall to any extent be invalid or unenforceable, the remainder of this Lease, or the application of such term to persons or circumstances other than those as to which it is invalid or unenforceable shall not be affected thereby, and each term of this Lease shall be valid and enforceable to the fullest extent permitted by law.

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8.6 Self-Help

If Tenant shall at any time default in the performance of any obligation under this Lease and such default shall continue for more than five (5) days after notice from Landlord plus such additional time, if any, as is reasonably necessary (but in no event to exceed thirty (30) additional days) to cure the default if the default is of such a nature that it cannot reasonably be cured in five (5) days provided Tenant commences to cure promptly and diligently pursues the cure to completion (except in the case of emergencies when no notice shall be required), Landlord shall have the right, but shall not be obligated, to enter upon the Premises and to perform such obligation notwithstanding the fact that no specific provision for such substituted performance by Landlord is made in this Lease with respect to such default. In performing such obligation, Landlord may make any payment of money or perform any other act. All sums so paid by Landlord (together with interest at the rate of two and one-half (2.5%) percentage points over the then prevailing prime rate as published in The Wall Street Journal) and all necessary incidental costs and expenses in connection with the performance of any such act by Landlord, shall be deemed to be additional rent under this Lease and shall be payable to Landlord immediately on demand. Landlord may exercise the foregoing rights without waiving any other of its rights or releasing Tenant from any of its obligations under this Lease.

8.7 Estoppel Certificate

Each party agrees from time to time, upon not less than fifteen (15) business days’ prior written request by the other party, to execute, acknowledge and deliver to the requesting party a statement in writing certifying, to the extent the same are accurate, that this Lease is unmodified and in full force and effect and that there are no uncured defaults of Landlord or Tenant under this Lease, and if Landlord is the requesting party that Tenant has no defenses, offsets or counterclaims against its obligations to pay the Fixed Rent and additional rent and to perform its other covenants under this Lease (or, if there have been any modifications that the same is in full force and effect as modified and stating the modifications and, if there are any defenses, offsets, counterclaims, or defaults, setting them forth in reasonable detail), the dates to which the Fixed Rent, additional rent and other charges have been paid and such other matters relating to the Lease as may be reasonably requested. Any such statement delivered pursuant to this Section 8.7 may be relied upon by a prospective purchaser or mortgagee of the Property or any prospective assignee of any mortgagee of the Property, or by a prospective assignee of Tenant’s interest in this Lease, as the case may be.

8.8 Waiver of Subrogation

Any property damage insurance carried by either party with respect to the Premises or property therein shall include a clause or endorsement denying to the insurer rights of subrogation against the other party. Each party, notwithstanding any provisions of this Lease to the contrary, hereby waives any rights of recovery against the other for injury or loss due to hazards covered by such insurance to the extent of the indemnification received thereunder.

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8.9 All Agreements Contained; Independent Covenants; Construction

This Lease contains all of the agreements of the parties with respect to the subject matter thereof and supersedes all prior dealings between them with respect to such subject matter. Each term, covenant, agreement, obligation or other provision of this Lease on Tenant’s part to be performed shall be deemed and construed as a separate and independent covenant of Tenant, not dependent upon any of the other terms of this Lease. This Lease shall be construed without regard to any presumption or other rule requiring construction against the party causing this Lease to be drafted.

8.10 Brokerage

Each party represents that it has had no dealings with any broker or agent other than the Broker(s) identified in Section 1.2 in connection with this Lease and covenants to defend, hold harmless and indemnify the other party and its agents from and against any and all cost, expense or liability resulting from a breach of the foregoing representation. Landlord will pay the commissions due the aforesaid Broker in accordance with separate commission agreements.

8.11 Submission Not an Option

The submission of this Lease or a summary of some or all of its provisions for examination does not constitute a reservation of or option for the Premises or an offer to lease, and it is not effective as a lease or otherwise until the execution by and delivery to both Landlord and Tenant.

8.12 Applicable Law

This Lease, and the rights and obligations of the parties hereto, shall be construed and enforced in accordance with the laws of the Commonwealth of Massachusetts.

8.13 Waiver of Jury Trial

LANDLORD AND TENANT HEREBY WAIVE TRIAL BY JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM BROUGHT BY EITHER OF THE PARTIES HERETO AGAINST THE OTHER, ON OR IN RESPECT TO ANY MATTER WHATSOEVER ARISING OUT OF OR IN ANY WAY CONNECTED WITH THIS LEASE, THE RELATIONSHIP OF LANDLORD AND TENANT HEREUNDER, TENANT’S USE OR OCCUPANCY OF THE PREMISES, AND/OR CLAIM OF INJURY OR DAMAGES.

8.14 Access and Security

Tenant shall have access to the Premises at all times during the Term of this Lease, except in the event of an emergency or for safety precautions. The Building is accessed by an automated card key system. Landlord may require that parties desiring to enter the Building after regular office hours must provide proper identification. Tenant shall be responsible for any security required for Tenant’s property in or around the Premises, including, but not limited to, the loading area. In connection with the foregoing, Tenant shall have the right, subject to the prior written consent of Landlord, to install a security system for Premises at Tenant’s sole cost and expense.

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8.15 Holdover

Should Tenant holdover in occupancy of the Premises after the expiration or other termination of the Term of this Lease, without the consent of Landlord, such holding over shall be as a tenant at sufferance and Tenant shall be liable to Landlord for (i) use and occupancy equal to the greater of one hundred and fifty percent (150%) percent of then-current market value rent or the Fixed Rent and additional rent in effect at the end of the Term, for the first month during such holding over, (ii) use and occupancy equal to the greater of two hundred percent (200%) percent of then-current market value rent or the Fixed Rent and additional rent in effect at the end of the Term, for each month after the first month of such holding over, and (iii) all damages sustained by Landlord on account of such holding over. The provisions of this Section shall not operate as a waiver of any right of reentry provided in this Lease.

8.16 Limitation on Liability

In consideration of the benefits accruing hereunder, Tenant hereby covenants and agrees that, in the event of any actual or alleged failure, breach or default hereunder by Landlord:

(a) The obligations of Landlord under this Lease do not constitute personal obligations of the members, trustees, individual partners, directors, officers or shareholders of Landlord or any constituent entity of Landlord, and Tenant shall not seek recourse against the members, trustees, partners, directors, officers or shareholders of Landlord or any constituent entity of Landlord, or any of their personal assets for satisfaction of any liability with respect to this Lease.

(b) Tenant’s sole and exclusive remedy shall be against Landlord’s interest in the Property.

(c) These covenants and agreements are enforceable by Landlord, and shall bind Tenant and its successors and assigns.

8.17 Security Deposit

On or prior to the date hereof, Tenant shall provide Landlord with a letter of credit in form and substance satisfactory to Landlord and from a financial institution satisfactory to Landlord in its reasonable judgment in the original amount of $77,163.25. Tenant shall maintain such letter of credit until the date that is forty-five (45) days after expiration of the Term. Tenant may reduce the security deposit to $51,442.17 on the first anniversary of the Rent Commencement Date, provided that no defaults have occurred under this Lease beyond applicable notice and grace periods, and further provided that upon any default by Tenant under the Lease beyond applicable notice and grace periods (even if occurring following such reduction), Tenant shall restore any amount of the letter of credit drawn by the Landlord on account of such default and increase the letter of credit to its original amount of $77,163.25 for the duration of the Term of the Lease. Such letter of credit may be drawn from time to time by Landlord upon Tenant’s default of its obligations under this Lease beyond applicable notice and

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grace periods, or if such letter of credit is about to expire and has not been renewed within thirty (30) days preceding such expiration. Should Landlord draw down the letter of credit, Tenant shall be obligated to restore it to its original amount. Landlord may assign the security deposit to a successor or transferee and, following the assignment, Landlord shall have no further liability with respect to the security deposit. If the letter of credit is drawn down and held by Landlord as a cash security deposit, Landlord (i) shall not be required to keep the security deposit separate from its other accounts, and (ii) shall return any unapplied portion of the security deposit to Tenant within forty-five (45) days after the later to occur of the expiration of the Term or the date Tenant surrenders the Premises to Landlord in compliance with Section 5.2.

8.18 Representations

Tenant guarantees, warrants and represents that (a) Tenant is duly incorporated or otherwise established or formed and validly existing under the laws of its state of incorporation, establishment or formation, (b)Tenant has and is duly qualified to do business in the state in which the Property is located, (c) Tenant has full corporate, partnership, trust, association or other appropriate power and authority to enter into this Lease and to perform all Tenant’s obligations hereunder, (d) each person (and all of the persons if more than one signs) signing this Lease on behalf of Tenant is duly and validly authorized to do so and (e) neither (i) the execution, delivery or performance of this Lease nor (ii) the consummation of the transactions contemplated hereby will violate or conflict with any provision of documents or instruments under which Tenant is constituted or to which Tenant is a party.

Tenant guarantees, warrants and represents that none of (x) it, or (y) to the best of its actual knowledge, its affiliates, partners, members, shareholders or other equity owners or any of their respective employees, officers, directors, representatives or agents is a person or entity with whom U.S. persons or entities are restricted from doing business under regulations of the Office of Foreign Asset Control (“OFAC”) of the Department of the Treasury (including those named on OFAC’s Specially Designated and Blocked Persons List) or under any statute, executive order (including the September 24, 2001, Executive Order Blocking Property and Prohibiting Transactions with Persons Who Commit, Threaten to Commit, or Support Terrorism) or other similar governmental action.

ARTICLE IX

RIGHTS OF PARTIES HOLDING PRIOR INTERESTS

9.1 Lease Subordinate

This Lease shall be subject and subordinate to any mortgage now or hereafter on the Property, and to each advance made or hereafter to be made under any mortgage, and to all renewals, modifications, consolidations, replacements and extensions thereof and all substitutions therefor. Landlord represents that the Property is not presently encumbered by a mortgage. Tenant’s obligation to subordinate this Lease to a future mortgage is expressly conditioned upon Tenant receiving from the holder thereof an agreement with Tenant in such holder’s standard form by the terms of which such holder will agree to recognize the rights of Tenant under this Lease and to accept Tenant as tenant of the Premises under the terms and

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conditions of this Lease in the event of acquisition of title by such holder through foreclosure proceedings or otherwise and Tenant will agree to recognize and attorn to the holder of such mortgage as Landlord in such event, which agreement shall be made expressly to bind and inure to the benefit of the successors and assigns of Tenant and of the holder and upon anyone purchasing the Premises at any foreclosure sale. Notwithstanding the foregoing, any such holder may at its election subordinate its mortgage to this Lease without the consent or approval of Tenant. Tenant agrees to execute and deliver any appropriate instruments containing terms and provisions commonly contained in such instruments necessary to carry out the agreements contained in this Section 9.1.

9.2 Rights of Holder of Mortgage to Notice of Defaults by Landlord and to Cure Same

No act or failure to act on the part of Landlord which would entitle Tenant under the terms of this Lease, or by law, to be relieved of Tenant’s obligations hereunder or to terminate this Lease, shall result in a release or termination of such obligations or a termination of this Lease unless (i) Tenant shall have first given written notice of Landlord’s act or failure to act to Landlord’s mortgagees of record of whom Landlord has given Tenant notice, if any, specifying the act or failure to act on the part of Landlord which could or would give basis to Tenant’s rights; and (ii) such mortgagees after receipt of such notice, have failed or refused to correct or cure the condition complained of within a reasonable time thereafter; but nothing contained in this Section 9.2 shall be deemed to impose any obligation on any such mortgagees to correct or cure any condition. “Reasonable time” as used above means and includes a reasonable time to obtain possession of the mortgaged premises if the mortgagee elects to do so and a reasonable time to correct or cure the condition if such condition is determined to exist.

[Signatures on following page]

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EXECUTED as a sealed instrument in two or more counterparts on the day first above written.

LANDLORD:

WALTHAM WINTER STREET 890 LP, a

Delaware limited partnership, doing business in Massachusetts as Waltham Winter Street 890 Limited Partnership

By: Waltham Sub GP LLC, a Delaware limited         liability company, its General Partner

          By: Clarion Partners, LLC, a New York

                  limited liability company, its Manager

                By: /s/ Xxxxx Xxxxxxx                            

                Name: Xxxxx Xxxxxxx

                Title: Authorized Signatory

TENANT:

                ARSANSIS, INC., a Delaware corporation:

                By: /s/ Xxxx Xxxxx                            

                Name: Xxxx Xxxxx

                Title: Executive Director – U.S. Business Operations

Signature Page to Lease

S-1

EXHIBIT A

Property Description

That certain parcel of land situate in the City of Waltham in the County of Middlesex, Commonwealth of Massachusetts, described as follows:

Parcel 1:

Xxx 0 xx xxxxx xx Xxxx Xxxxx Xxxx Xx. 00000X.

Parcel 2:

Lot N as shown on plan entitled “Plan of Land in Waltham, Massachusetts prepared for 000 Xxxxxx Xxxxxx, L.L.C. and 000 Xxxxxx Xxxxxx, L.L.C.” dated May 19, 1998 by Xxxxxxxxx Engineering Associates, Inc. and recorded with the Middlesex South District Registry of Deeds as Plan No. 734 of 1998.

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EXHIBIT B

Floor Plan

[TO BE ATTACHED]

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EXHIBIT C

[RESERVED]

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EXHIBIT D

Landlord’s Services

I. Cleaning

A. Office Area

Daily on Business Days:

1. Empty and clean all waste receptacles and ash trays and remove waste material from the Premises; wash receptacles as necessary.

2. Sweep and dust mop all non-carpeted areas.

3. Vacuum all rugs and carpeted areas.

4. Hand dust and wipe clean with treated cloths all horizontal surfaces including furniture, office equipment, window xxxxx, door ledges, chair rails, and convector tops, within normal reach.

5. Wash clean all water fountains.

6. Remove and dust under all desk equipment and telephones and replace same.

7. Wipe clean all brass and other bright work.

8. Hand dust all grill work within normal reach.

9. Upon completion of cleaning, all lights will be turned off and doors locked, leaving the Premises in an orderly condition

Weekly:

1. Dust coat racks and the like.

2. Remove all finger marks from private entrance doors, light switches and doorways.

3. Clean all interior glass, including sidelights and conference room glass walls.

Monthly:

4. All vinyl floor surfaces will be cleaned

Quarterly:

Render high dusting not reached in daily cleaning to include:

5. Dusting all pictures, frames, charts, graphs and similar wall hangings.

6. Dusting all pipes, ducts and high moldings.

7. Dusting all venetian blinds.

B. Lavatories

Daily on Business Days:

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1. Sweep and damp mop floors.

2. Clean all mirrors, powder shelves, dispensers and receptacles, bright work, flushometers, piping and toilet seat hinges.

3. Wash both sides of toilet seats.

4. Wash all basins, bowls and urinals.

5. Dust and clean all powder room fixtures.

6. Empty and clean paper towel and sanitary disposal receptacles.

7. Remove waste paper and refuse.

8. Refill tissue holders, soap dispensers, towel dispensers, vending sanitary dispensers; materials to be furnished by Landlord.

9. A sanitizing solution will be used in all lavatory cleaning.

Monthly:

10. Machines scrub lavatory floors.

11. Wash all partitions and tile walls in lavatories.

C. Main Lobby, Elevators, Building Exterior and Corridors

Daily on Business Days:

1. Sweep and wash all floors.

2. Wash all rubber mats.

3. Clean elevators, wash or vacuum floors, wipe down walls and corridors.

4. Spot clean any metal work inside lobby.

5. Spot clean any metal work surrounding Building entrance doors.

6. Clean glass, where appropriate.

Monthly:

All resilient tile floors in public areas to be treated equivalent to spray buffing.

As Needed:

Ash urns in Building exterior.

D. Exterior Windows

Biannually:

Wash exterior windows.

II. Heating, Ventilating and Air Conditioning

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A. Heating, ventilating, and air conditioning (“HVAC”) as required to provide reasonably comfortable temperatures for normal business day occupancy (excepting holidays); Mondays through Fridays from 8:00 am to 6:00 pm and 9 am to 1 pm on Saturdays, provided that as part of Landlord’s environmental commitment, Saturday morning’s HVAC services are provided only as requested by each tenant of the Building. HVAC provided during days or hours other than those described herein shall be provided to Tenant at the rate established by Landlord, currently $60 per hour.

B. Maintenance and use of any additional or special air conditioning equipment and the associated operating cost will be at Tenant’s expense. A 24-hour notice is needed to program additional comfort.

C. Holidays are defined for all purposes of this Lease, as the following days: New Year’s Day, Xxxxxx Xxxxxx Xxxx Day, President’s Day, Patriot’s Day, Memorial Day, Independence Day, Labor Day, Columbus Day, Veteran’s Day, Thanksgiving Day and Christmas, and other days defined as “legal holidays” for the entire state under the laws of the Commonwealth of Massachusetts.

III. Water

Hot and cold water, in reasonable quantities, for lavatory, pantry, drinking and toilet purposes.

IV. Elevators (Passenger and Freight)

A. Passenger: Elevators for the use of all tenants and the general public for access to and from all floors of the Building.

B. Freight: Elevators for use by all tenant deliveries for access to and from all floors of the Building.

C. Building Directory: Landlord will furnish and install Building Directory tablets, at Landlord’s expense, and the number of listings thereon for Tenant and any permitted occupants of the Premises shall be at the discretion of Landlord.

V. Electricity

A. Electricity to the Premises as set forth in Section 2.9 of the Lease. Tenant’s use of electric energy in Tenant’s Space shall not at any time exceed the capacity of any of the

electrical conductors or equipment in or otherwise serving Tenant’s Space. In order to ensure that such capacity is not exceeded and to avert possible adverse effect upon the Building electric service, Tenant shall not, without prior written notice to Landlord in each instance, connect to the Building electric distribution system any fixtures, appliance or equipment which operate on a voltage in excess of 120 volts nominal or make any material alteration or addition to the electrical system of Tenant’s Space. All additional risers or other equipment required by Tenant shall be provided by Landlord and the cost thereof shall be paid by Tenant upon Landlord’s demand.

B. Lighting of the parking areas, walkways, Building entrance, lobbies, elevators and other common areas of the Building.

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VI. Lot.

A. Snow and ice removal from the driveways, parking areas, walkways and Building entrance.

B. Landscaping consistent with a first-class office park in the Route 128 West Office market.

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EXHIBIT E

Landlord’s Rules and Regulations

I. The following regulations are generally applicable:

1. The public sidewalks, entrances, passages, courts, elevators, vestibules, stairways, corridors or halls shall not be obstructed or encumbered by Tenant (except as necessary for deliveries) or used for any purpose other than ingress and egress to and from the Premises.

2. Landlord shall furnish Building standard blinds for all exterior windows. No awnings, curtains, blinds, shades, screens or other projections shall be attached to or hung in, or used in connection with, any exterior window of the Premises or any outside wall of the Building. Such awnings, curtains, blinds, shades, screens or other projections must be of a quality, type, design and color, and attached in the manner, approved by Landlord.

3. No show cases or other articles shall be put in front of or affixed to any part of the exterior of the Building, nor placed in the halls, corridors or vestibules.

4. The water and wash closets and other plumbing fixtures shall not be used for any purposes other than those for which they were designed and constructed, and no sweepings, rubbish, rags, acids or like substances shall be deposited therein. All damages resulting from any misuse of the fixtures by Tenant shall be borne by the Tenant.

5. Tenant shall not use the Premises or any part thereof, or permit the Premises or any part thereof to be used, for manufacturing. Tenant shall not use the Premises or any part thereof or permit the Premises or any part thereof to be used as a public employment bureau or for the sale of property of any kind at auction, except in connection with Tenant’s business.

6. Tenant must upon the termination of its tenancy, restore to the Landlord all locks, cylinders and keys to offices and toilet rooms of the Premises.

7. The Landlord reserves the right to exclude from the Building between the hours of 6 p.m. and 8 a.m. and at all hours on Sunday and holidays all persons connected with or calling upon the Tenant who do not present a pass to the Building signed by the Tenant. Tenant shall be responsible for all persons for whom it issues any such pass and shall be liable to the Landlord for all wrongful acts of such persons.

8. The requirements of Tenant will be attended to only upon application at the Building Superintendent’s Office. Employees of Landlord shall not perform any work or do anything outside of their regular duties, unless under special instructions from the office of the Landlord.

9. There shall not be used in any space, or in the public halls of the Building, either by Tenant or by jobbers or others, in the delivery or receipt of merchandise, any hand trucks, except those equipped with rubber tires and side guards.

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10. No bicycles, vehicles or animals of any kind shall be brought into or kept in or about the Premises, except guide dogs where necessary.

11. No Tenant shall make, or permit to be made, any unseemly or disturbing noises or disturb or interfere with occupants of this or neighboring building or premises or those having business with them whether by use of any musical instrument, radio, talking machine, unmusical noise, whistling, singing, or in any other way. No Tenant shall throw anything out of the doors, windows or skylights or down the passageways.

12. The Premises shall not be used for lodging or sleeping or for any immoral or illegal purpose.

13. No smoking shall be permitted in the Premises or the Building. Smoking shall only be permitted in smoking areas outside of the Building which have been designated by the Landlord.

14. Tenants shall reasonably cooperate with Landlord in obtaining maximum effectiveness of the cooling system by closing draperies when the sun’s rays fall directly on the windows of the Premises.

15. Landlord shall have the right, exercisable without notice and without liability to any tenant, to change the name and street address of the Building. Landlord shall promptly notify Tenant after any such changes have been made.

16. Any person desiring to use the health and fitness facility shall first execute and deliver to the Landlord a liability waiver form prepared by the Landlord.

II. The following regulations are applicable to any additions, alterations or improvements being undertaken by or for Tenant in the Premises:

A. General

1. All alterations to be made by Tenant in, to or about the Premises shall be subject to Landlord’s prior written approval and made in accordance with the requirements of this Exhibit and by contractors, subcontractors and/or mechanics approved by Landlord, such approval not be unreasonably withheld or delayed; provided, however, Landlord’s consent shall not be required for alterations of a cosmetic nature (such as painting, carpeting, wall papering).

2. Tenant shall, prior to the commencement of any work, submit for Landlord’s written approval, complete plans for the alterations except that no plans or drawings shall be required for cosmetic alterations (such as painting, carpeting, wall papering). Drawings are to be complete with full details and specifications for all of the alterations.

3. Alterations must comply with the Building Code applicable to the Property and the requirements, rules and regulations of any governmental agencies having jurisdiction over the Property.

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4. No work shall be permitted to commence without the Landlord being furnished with a valid permit and all other necessary approvals from agencies having jurisdiction.

5. All demolition, removals or other categories of work that may inconvenience other tenants or disturb Building operations, must be scheduled and performed before or after normal Business Hours and Tenant shall provide the Building manager with at least 24 hours’ notice prior to proceeding with such work.

6. All inquiries, submissions, approvals and all other matters regarding alterations to the Premises shall be processed through the Building manager.

B. Prior to Commencement of Work

1. Tenant shall submit to the Building manager a request to perform the work. The request shall include the following enclosures:

(i) A list of Tenant’s contractors and/or subcontractors for Landlord’s approval.

(ii) Where appropriate, four complete sets of plans and specifications properly stamped by a registered architect or professional engineer.

(iii) A properly executed building permit application form.

(iv) Four executed copies of the Insurance Requirements agreement in the form attached to this Lease as Exhibit F from Tenant’s contractor and if requested by Landlord from the contractor’s subcontractors.

(v) Contractor’s and subcontractor’s insurance certificates including an indemnity in accordance with the Insurance Requirements agreement.

2. Landlord will return the following to Tenant:

(i) Two sets of plans approved or a disapproval with specific comments as to the reasons therefor (such approval or comments shall not constitute a waiver of approval of governmental agencies) along with Landlord’s response to Tenant’s request for identification of alterations that will be required to be removed at the expiration of the Term, as more fully provided in Section 5.2 of the Lease.

(ii) Two fully executed copies of the Insurance Requirements agreement.

3. Tenant shall obtain a building permit from the Building Department and necessary permits from other governmental agencies. Tenant shall be responsible for keeping current all permits. Tenant shall submit copies of all approved plans and permits to Landlord and shall post the original permit on the Premises prior to the commencement of any work. All work, if performed by a contractor or subcontractor, shall be subject to reasonable supervision and inspection by Landlord’s Construction Representative. Such supervision and inspection shall be at Tenant’s sole expense and Tenant shall pay Landlord’s reasonable charges for such supervision and inspection.

C. Requirements and Procedures

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1. All structural and floor loading requirements shall be subject to the prior approval of Landlord’s structural engineer.

2. All mechanical (HVAC, plumbing and sprinkler) and electrical requirements shall be subject to the approval of Landlord’s mechanical and electrical engineers and all mechanical and electrical work shall be performed by contractors approved by Landlord, which approval shall not be unreasonably withheld or delayed. When necessary, Landlord will require engineering and shop drawings, which drawings must be approved by Landlord before work is started, not to be unreasonably withheld or delayed. Drawings are to be prepared by Tenant and all approvals shall be obtained by Tenant.

3. Elevator service for construction work shall be without charge to Tenant. Prior arrangements for elevator use shall be made with Building manager by Tenant. No material or equipment shall be carried under or on top of elevators. If an operating engineer is required by any union regulations, such engineer shall be paid for by Tenant.

4. If shutdown of risers and mains for electrical, HVAC, sprinkler and plumbing work is required, such work shall be supervised by Landlord’s Construction Representative. No work will be performed in Building mechanical equipment rooms without Landlord’s approval and under Landlord’s supervision.

5. Tenant’s contractor shall:

(i) have a superintendent or xxxxxxx on the Premises at all times that construction is active;

(ii) police the job at all times, continually keeping the Premises orderly;

(iii) maintain cleanliness and protection of all areas, including elevators and lobbies;

(iv) protect the front and top of all peripheral HVAC units and thoroughly clean them at the completion of work;

(v) block off supply and return grills, diffusers and ducts to keep dust from entering into the Building air conditioning system; and

(vi) avoid the disturbance of other tenants.

6. If Tenant’s contractor is negligent in any of its responsibilities, Tenant shall be charged for corrective work.

7. All equipment and installations must be equal to the standards generally in effect with respect to the remainder of the Building. Any deviation from such standards will be permitted only if indicated or specified on the plans and specifications and approved by Landlord.

8. A properly executed air balancing report signed by a professional engineer shall be submitted to landlord upon the completion of all HVAC work.

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9. Upon completion of the alterations, Tenant shall submit to Landlord a permanent certificate of occupancy and final approval by the other governmental agencies having jurisdiction, where required.

10. Where appropriate, Tenant shall submit to Landlord a final “as-built” set of drawings showing all items of the alterations in full detail.

11. Additional and differing provisions in the Lease, if any, will be applicable and will take precedence.

III. The following regulations shall be effective with respect to any plans or specifications that Tenant is required to prepare under the Lease:

Whenever Tenant shall be required by the terms of the Lease to submit plans to Landlord in connection with any improvement or alteration to the Premises, such plans shall include at least the following:

1. Floor plan indicating location of partitions and doors (details required of partition and door types).

2. Location of standard electrical convenience outlets and telephone outlets.

3. Location and details of special electrical outlets: e.g., photocopiers, etc.

4. Reflected ceiling plan showing layout of standard ceiling and lighting fixtures. Partitions to be shown lightly with switches located indicating fixtures to be controlled.

5. Locations and details of special ceiling conditions, lighting fixtures, speakers, etc.

6. Location and specifications of floor covering, paint, or paneling with paint colors referenced to standard color system.

7. Finish schedule plan indicating wall covering, paint, or paneling with paint colors referenced to standard color system.

8. Details and specifications of special millwork, glass partitions, rolling doors and grilles, blackboards, shelves, etc.

9. Hardware schedule indicating door number keyed to plan, size, hardware required including butts, latchsets or locksets, closures, stops and any special items such as thresholds, soundproofing, etc. Keying schedule is required.

10. Verified dimensions of all built-in equipment (file cabinets, lockers, plan files, etc.)

11. Location and weights of storage files.

12. Location of any special soundproofing requirements.

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00. Location and details of special floor areas exceeding 50 pounds of live load per square foot.

14. All structural, mechanical, plumbing and electrical drawings, to be prepared by the base building consulting engineers, necessary to complete the Premises in accordance with Tenant’s plans.

15. All drawings to be uniform size (30’ x 46’) and shall incorporate the standard project electrical and plumbing symbols and be at a scale of 1/8” = 1’ or larger.

16. All drawings shall be stamped by an architect (or, where applicable, an engineer) licensed in the jurisdiction in which the Property is located and without limiting the foregoing, shall be sufficient in all respects for submission to applicable governmental authorities in connection with a building permit application.

17. Landlord’s approval of the plans, drawings, specifications or other submissions in respect of any work, addition, alteration or improvement to be undertaken by or on behalf of Tenant shall create no liability or responsibility on the part of Landlord for their completeness, design sufficiency or compliance with requirements of any applicable laws, rules or regulations of any governmental or quasi-governmental agency, board or authority.

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EXHIBIT F

CONTRACTOR’S INSURANCE

Building: 000 Xxxxxx Xxxxxx, Xxxxxxx, XX

Tenant:                                                  

Premises:                      Rentable Square Feet of Space in the Building.

The undersigned contractor or subcontractor (“Contractor”) has been hired by the tenant or occupant (hereinafter called “Tenant”) of the Building named above or by Tenant’s contractor to perform certain work (“Work”) for Tenant in the Premises identified above. Contractor and Tenant have requested the undersigned landlord (“Landlord”) to grant Contractor access to the Building and its facilities in connection with the performance of the Work and Landlord agrees to grant such access to Contractor upon and subject to the following terms and conditions:

1. Contractor agrees to indemnify and save harmless the Landlord, Landlord’s affiliates and their respective officers, employees, agents, members and partners and each of them, from and with respect to any claims, demands, suits, liabilities, losses and expenses, including reasonable attorneys’ fees, arising out of or in connection with the Work (and/or imposed by law upon any or all of them) because of personal injuries, bodily injury (including death at any time resulting therefrom) and loss of or damage to property, whether such injuries to person or property are claimed to be due to negligence of the Contractor, Tenant, Landlord or any other party entitled to be indemnified as aforesaid except to the extent specifically prohibited by law (and any such prohibition shall not void this Agreement but shall be applied only to the minimum extent required by law).

2. Contractor shall provide and maintain at its own expense, until completion of the Work, the following insurance:

(a) Worker’s Compensation (including coverage for Occupational Disease) and Employers Liability Insurance covering each and every xxxxxxx employed in, about or upon the Work, as provided for in each and every statute applicable to Workmen’s Compensation and Employers’ Liability Insurance.

(b) Comprehensive General Liability Insurance including coverages for Protective and Contractual liability (to specifically include coverage for the indemnification clause of this Agreement) for not less than the following limits:

(c) Personal Injury: $3,000,000 per person, $5,000,000 per occurrence

(d) Property Damage: $3,000,000 per occurrence $3,000,000 aggregate

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(e) Comprehensive Automobile Liability Insurance (covering all owned, non-owned and/or hired motor vehicles to be used in connection with the Work) for not less than the following limits:

(i) Bodily Injury: $1,000,000 per person, $1,000,000 per occurrence

(ii) Property Damage: $1,000,000 per occurrence

(f) Contractor shall furnish a certified from its insurance carrier or carriers to the Building office before commencing the Work, showing that it has complied with the above requirements regarding insurance and providing that the insurer will endeavor to give Landlord ten (10) days’ prior written notice of the cancellation of any of the foregoing policies.

(g) Contractor shall require all of its subcontractors engaged in the Work to provide the following insurance:

(i) Comprehensive General Liability Insurance including Protective and Contractual Liability coverages with limits of liability at least equal to the limits stated in paragraph 2(b).

(ii) Comprehensive Automobile Liability Insurance (covering all owned, non-owned and/or hired motor vehicles to be used in connection with the Work) with limits of liability at least equal to the limits stated in paragraph 2(c).

[Remainder of Page Left Blank Intentionally]

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Upon the request of Landlord, Contractor shall require all of its subcontractors engaged in the Work to execute an Insurance Requirements Agreement in the same form as this Agreement.

Agreed to and executed this                  day of                     , 20 .

LANDLORD:

Waltham Winter Street 890 LP, a Delaware limited partnership

By:		Waltham Winter Street LLC, a Delaware limited liability company, its General Partner
		By: Clarion Partners LLC, a New York limited       liability company, its Manager
		By:                                                                         Name:
		Title:

CONTRACTOR:

By:

Name:

Title:

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