INSTRUMENT IS AN INDENTURE OF LEASE

 

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                                                                    Exhibit 10.8

 

 

 

                               91 HARTWELL AVENUE

                            LEXINGTON, MASSACHUSETTS

 

                          Lease Dated January 13, 2005

 

          THIS INSTRUMENT IS AN INDENTURE OF LEASE in which the Landlord and the

Tenant are the parties hereinafter named, and which relates to space in a

certain building (the "Building") known as, and with an address at, 91 Hartwell

Avenue, Lexington, Massachusetts.

 

         The parties to this Indenture of Lease hereby agree with each other as

follows:

 

                                    ARTICLE I

                                    ---------

 

                                 REFERENCE DATA

                                  --------------

 

1.1       SUBJECTS REFERRED TO.

         ---------------------

 

         Each reference in this Lease to any of the following subjects shall be

         construed to incorporate the data stated for that subject in this

          Article:

 

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<S>                                                        <C>

         Landlord:                                         Mortimer B. Zuckerman and Edward H. Linde, Trustees

                                                          of 91 Hartwell Avenue Trust under Declaration of

                                                          Trust dated September 28, 1981 filed with the

                                                          Middlesex South Registry as Document No. 616455 as

                                                          amended by instruments dated December 10, 1984 and

                                                          April 17, 1991 respectively filed with said Registry

                                                           District as Document Nos. 675674 and 844541 but not

                                                          individually.

 

         Landlord's Original Address:                      c/o Boston Properties Limited Partnership

                                                           111 Huntington Avenue, Suite 300

                                                          Boston, Massachusetts 02199-7610

 

         Landlord's Construction Representative:           Michael Schumacher

 

         Tenant:                                           Synta Pharmaceuticals, Inc., a Delaware corporation.

 

         Tenant's Original Address:                        45 Hartwell Avenue

                                                          Lexington, Massachusetts 02421

 

 

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         Tenant's Construction Representative:

                                                          ------------------------------------

 

         Commencement Date:                                January 15, 2005

 

          Second Floor Premises Rent                        February 15, 2005

         Commencement Date:

 

         Third Floor Premises Rent                         July 1, 2005

         Commencement Date:

 

         Original Term:                                     Twenty-five (25) calendar months (plus

                                                          the partial month, if any, immediately

                                                          following the Commencement Date),

                                                           unless extended or sooner terminated as

                                                          provided in this Lease.

 

         Extension Option:                                 One (1) period of one (1) year as provided in and on

                                                          the terms set forth in Section 2.4.1 hereof.

 

         Term or Lease Term:                               All references in this Lease or to the Term

                                                           or Lease Term shall mean the Original Term

                                                          and if extended pursuant to Section 2.4.1, the Original

                                                          Term as extended by the exercise of the extension option

                                                          unless otherwise specifically provided in this Lease.

 

         The Site:                                         That certain parcel of land known as and numbered 91

                                                          Hartwell Avenue, Lexington, Middlesex Count, Massachusetts,

                                                          being more particularly described in Exhibit A attached

                                                           hereto. The Building (as defined below) is the only structure

                                                          located on the Site.

 

         The Building:                                     The Building known as and numbered 91 Hartwell

                                                          Avenue, Lexington, Massachusetts.

 

         The Complex:                                      The Building together with all surface parking areas,

                                                           the Site and all improvements (including landscaping)

                                                          thereon and thereto.

 

         Tenant's Space:                                   A portion of the second (2nd) floor of the Building

                                                          (the "Second Floor Premises") and a portion of the

                                                          third (3rd) floor of the Building (the "Third Floor

                                                           Premises"), in

 

 

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                                                          accordance with the floor plan annexed

                                                           hereto as Exhibit D and incorporated herein by

                                                          reference.

 

         Number of Parking Spaces:                         Seventy-six (76) spaces.

 

         Annual Fixed Rent:                                 (a)   With respect to the Second Floor Premises, for

                                                          the period commencing on the Second Floor Premises

                                                          Rent Commencement Date and ending on the last day of

                                                          the Original Term of this Lease at the annual rate of

                                                          $268,398.00, being the product of (i) $19.50 and (ii)

                                                          the "Rentable Floor Area of the Second Floor

                                                          Premises" (hereinafter defined in this Section 1.1).

 

                                                           (b) With respect to the Third Floor Premises, for the

                                                          period commencing on the Third Floor Premises Rent

                                                          Commencement Date and ending on the last day

                                                          of the Original Term of this Lease at the annual rate of

                                                          $157,326.00, being the product of (i) $19.50

                                                           and (ii) the "Rentable Floor Area of the Third Floor

                                                          Premises" (hereinafter defined in this Section 1.1).

 

                                                           (c)   During the extension option period (if

                                                          exercised), as determined pursuant to Section 2.4.1).

 

         Operating Expenses:                               As provided in Section 2.6 hereof.

 

         Real Estate Taxes:                                As provided in Section 2.7 hereof.

 

         Tenant Electricity:                               Initially as provided in Section 2.5 subject to

                                                           adjustment as provided in Section 2.8 hereof.

 

         Additional Rent:                                  All charges and other sums payable by Tenant as set

                                                          forth in this Lease, in addition to Annual Fixed Rent.

 

         Rentable Floor Area of Tenant's Space             21,832 rentable square feet, consisting of 13,764

         (sometimes also called "Rentable Floor            square feet of rentable floor area in the Second

         Area of the Premises"):                           Floor Premises (the "Rentable Floor Area of the

                                                          Second Floor Premises") and 8,068 square feet of

                                                           rentable floor area in the Third Floor Premises (the

                                                          "Rentable Floor Area of the Third Floor Premises").

 

 

                                      -3-

 

 

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         Total Rentable Floor Area of the Building:        122,328 rentable square feet.

 

         Permitted Use:                                    General office purposes.

 

         Initial Minimum Limits of Tenant's                $5,000,000.00 combined single limit per occurrence on

          Commercial General Liability Insurance:           a per location basis.

 

         Broker:                                           Richards Barry Joyce & Partners

                                                          53 State Street, 29th Floor

                                                           Boston, Massachusetts 02110

 

         Security Deposit:                                 $35,477.00

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1.2       EXHIBITS.

         ---------

 

         There are incorporated as part of this Lease:

 

         Exhibit A          --        Description of Site

 

         Exhibit B          --        Intentionally Omitted

 

         Exhibit C          --        Landlord's Services

 

         Exhibit D          --        Floor Plan

 

         Exhibit E          --         Intentionally Omitted

 

         Exhibit F          --        Form of Lien Waivers

 

 

1.3       TABLE OF ARTICLES AND SECTIONS.

         -------------------------------

 

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         ARTICLE I.......................................................................................1

                  REFERENCE DATA..................................................................................1

                           1.1       SUBJECTS REFERRED TO..........................................................1

                           1.2       EXHIBITS......................................................................4

                            1.3       TABLE OF ARTICLES AND SECTIONS................................................4

 

         ARTICLE II......................................................................................6

                  BUILDING, PREMISES, TERM AND RENT...............................................................6

                           2.1       THE PREMISES..................................................................6

 

 

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                            2.2       RIGHTS TO USE COMMON FACILITIES...............................................6

                           2.3       LANDLORD'S RESERVATIONS.......................................................7

                           2.4       HABENDUM......................................................................8

                           2.5       FIXED RENT PAYMENTS...........................................................8

                           2.6       OPERATING EXPENSES............................................................9

                           2.7       REAL ESTATE TAXES............................................................11

                           2.8       TENANT ELECTRICITY...........................................................14

 

         ARTICLE III....................................................................................15

                  CONDITION OF PREMISES; ALTERATIONS.............................................................15

                            3.1       CONDITION OF PREMISES........................................................15

                           3.2       QUALITY AND PERFORMANCE OF WORK..............................................15

                           3.3       SPECIAL ALLOWANCE............................................................15

 

         ARTICLE IV.....................................................................................16

                  LANDLORD'S COVENANTS; INTERRUPTIONS AND DELAYS.................................................16

                           4.1       LANDLORD COVENANTS:..........................................................16

                           4.2       INTERRUPTIONS AND DELAYS IN SERVICES AND REPAIRS, ETC........................17

 

         ARTICLE V......................................................................................18

                  TENANT'S COVENANTS.............................................................................18

                            5.1       PAYMENTS.....................................................................18

                           5.2       REPAIR AND YIELD UP..........................................................18

                           5.3        USE..........................................................................18

                           5.4       OBSTRUCTIONS; ITEMS VISIBLE FROM EXTERIOR; RULES AND REGULATIONS.............19

                           5.5       SAFETY APPLIANCES............................................................19

                           5.6       ASSIGNMENT; SUBLEASE.........................................................19

                           5.7       INDEMNITY; INSURANCE.........................................................25

                           5.8       PERSONAL PROPERTY AT TENANT'S RISK...........................................26

                           5.9       RIGHT OF ENTRY...............................................................26

                           5.10      FLOOR LOAD; PREVENTION OF VIBRATION AND NOISE................................27

                           5.11      PERSONAL PROPERTY TAXES......................................................27

                            5.12      COMPLIANCE WITH LAWS.........................................................27

                           5.13      PAYMENT OF LITIGATION EXPENSES...............................................27

                           5.14      ALTERATIONS..................................................................28

                           5.15      VENDORS......................................................................29

 

         ARTICLE VI.....................................................................................30

                  CASUALTY AND TAKING............................................................................30

                           6.1       DAMAGE RESULTING FROM CASUALTY...............................................30

                           6.2       UNINSURED CASUALTY...........................................................31

                           6.3       RIGHTS OF TERMINATION FOR TAKING.............................................31

                           6.4       AWARD........................................................................32

 

 

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         ARTICLE VII....................................................................................32

                  DEFAULT   32

                           7.1       TENANT'S DEFAULT.............................................................32

                           7.2       LANDLORD'S DEFAULT...........................................................36

 

         ARTICLE VIII...................................................................................37

                  MISCELLANEOUS PROVISIONS.......................................................................37

                            8.1       EXTRA HAZARDOUS USE..........................................................37

                           8.2       WAIVER.......................................................................37

                           8.3       CUMULATIVE REMEDIES..........................................................37

                           8.4       QUIET ENJOYMENT..............................................................38

                           8.5       NOTICE TO MORTGAGEE AND GROUND LESSOR........................................39

                           8.6       ASSIGNMENT OF RENTS..........................................................39

                           8.7       SURRENDER....................................................................40

                           8.8       BROKERAGE....................................................................40

                           8.9       INVALIDITY OF PARTICULAR PROVISIONS..........................................40

                           8.10      PROVISIONS BINDING, ETC......................................................40

                           8.11      RECORDING....................................................................41

                            8.12      NOTICES......................................................................41

                           8.13      WHEN LEASE BECOMES BINDING...................................................42

                           8.14      SECTION HEADINGS.............................................................42

                           8.15      RIGHTS OF MORTGAGEE..........................................................42

                           8.16      STATUS REPORTS AND FINANCIAL STATEMENTS......................................43

                           8.17      SELF-HELP....................................................................43

                           8.18      HOLDING OVER.................................................................44

                           8.19      NON-SUBROGATION..............................................................44

                           8.20      SECURITY DEPOSIT.............................................................44

                           8.21      LATE PAYMENT.................................................................45

                           8.22      TENANT'S PAYMENTS............................................................45

                            8.23      WAIVER OF TRIAL BY JURY......................................................46

                           8.24      GOVERNING LAW................................................................46

</Table>

 

                                    ARTICLE II

                                   ----------

 

                        BUILDING, PREMISES, TERM AND RENT

                        ---------------------------------

 

2.1       THE PREMISES.

 

         Landlord hereby demises and leases to Tenant, and Tenant hereby hires

         and accepts from Landlord, Tenant's Space in the Building excluding

         exterior faces of exterior walls, the common stairways and stairwells,

         elevators and elevator wells, fan rooms, electric and telephone

         closets, janitor closets, 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.

 

 

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         Tenant's Space with such exclusions is hereinafter referred to as the

         "Premises." The term "Building" means the Building identified on the

         first page, and which is the subject of this Lease; the term "Site"

         means all, and also any part of the Land described in Exhibit A, plus

         any additions or reductions thereto resulting from the change of any

         abutting street line and all parking areas and structures. The term

         "Property" means the Building and the Site.

 

2.2       RIGHTS TO USE COMMON FACILITIES.

         -------------------------------

 

         Subject to Landlord's right to change or alter any of the following in

         Landlord's discretion as herein provided, Tenant shall have, as

         appurtenant to the Premises, the non-exclusive right 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 loading area of the Building, and the pipes, ducts,

         conduits, wires and appurtenant meters and equipment serving the

         Premises in common with others, (b) common walkways and driveways

         necessary for access to the Building, and (c) if the Premises include

         less than the entire rentable floor area of any floor, the common

         toilets, corridors and elevator lobby of such floor. Notwithstanding

         anything to the contrary herein, Landlord has no obligation to allow

         any particular telecommunication service provider to have access to the

         Building or to the Premises except as may be required by applicable

         law. If Landlord permits such access, Landlord may condition such

         access upon the payment to Landlord by the service provider of fees

         assessed by Landlord in its sole discretion.

 

         2.2.1     TENANT'S PARKING.

                  ----------------

 

                  In addition, Tenant shall have the right to use the Number of

                  Parking Spaces (referred to in Section 1.1) of the parking

                  area, in common with use by other tenants from time to time of

                  the Complex; provided, however, Landlord shall not be

                  obligated to furnish stalls or spaces in any parking area

                  specifically designated for Tenant's use. Tenant covenants and

                  agrees that it and all persons claiming by, through and under

                  it, shall at all times abide by all reasonable rules and

                  regulations promulgated by Landlord with respect to the use of

                  the parking areas on the Site. The parking privileges granted

                  herein are non-transferable except to a permitted assignee or

                   subtenant as provided in Section 5.6 through Section 5.6.6.

                  Further, Landlord assumes no responsibility whatsoever for

                  loss or damage due to fire, theft or otherwise to any

                  automobile(s) parked on the Site or to any personal property

                  therein, however caused, and Tenant covenants and agrees, upon

                  request from Landlord from time to time, to notify its

                  officers, employees, agents and invitees of such limitation of

                  liability. Tenant acknowledges and agrees that a license only

                  is hereby granted, and no bailment is intended or shall be

                  created.

 

2.3       LANDLORD'S RESERVATIONS.

         -----------------------

 

         Landlord reserves the right from time to time, without unreasonable

         interference with Tenant's use: (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

 

 

                                      -7-

 

 

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         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. Except in the event of an emergency,

         Landlord shall provide Tenant with forty-eight (48) hours advance

         notice of the above-referenced work if such work shall adversely

         affect Tenant's use of or access to the Premises, the common areas of

         the Site and/or the parking area.

 

2.4       HABENDUM.

         --------

 

         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 Article VI or Article VII or unless extended as provided

         in Section 2.4.1.

 

         2.4.1     EXTENSION OPTION.

                   ----------------

 

                  (A) On the conditions (which conditions Landlord may waive by

                  written notice to Tenant) that both at the time of exercise of

                  the option to extend and at the commencement date of the

                  extension option period (i) there exists no Event of Default

                  (defined in Section 7.1), (ii) this Lease is still in full

                  force and effect, and (iii) Tenant has not assigned this

                   (except for an assignment permitted without Landlord's consent

                  under Section 5.6.1 hereof), Tenant shall have the right to

                  extend the Term hereof upon all the same Annual Fixed Rent,

                  terms, conditions, covenants and agreements herein contained

                  (except that the only extension option shall be as set forth

                  in this Section 2.4.1) for one (1) period of one (1) year as

                  hereinafter set forth. Such option period is sometimes herein

                  referred to as an "Extended Term." Notwithstanding any

                  implication to the contrary Landlord has no obligation to make

                  any additional payment to Tenant in respect of any

                   construction allowance or the like or to perform any work to

                  the Premises as a result of the exercise by Tenant of such

                  option.

 

                  (B) If Tenant desires to exercise the option to extend the

                  Term, then Tenant shall give notice to Landlord, not earlier

                  than twelve (12) months nor later than six (6) months prior to

                  the expiration of the Original Term. Upon the giving of such

                   notice, this Lease and the Term hereof shall be extended for

                  the option period, without the necessity for the execution of

                  any additional documents (except that Landlord and Tenant

                  agree to enter into an instrument in writing setting forth the

                  fixed rent); and in such event all references herein to the

                  Term or the term of this Lease shall be construed as referring

                  to the Term, as so extended, unless the context clearly

                  otherwise requires.

 

2.5       FIXED RENT PAYMENTS.

         -------------------

 

         Tenant agrees to pay to Landlord, or as directed by Landlord, at

         Landlord's Original Address specified in Section 1.1 hereof, or at such

         other place as Landlord shall from time to time designate by notice,

         (1)(a) on the Second Floor Premises Rent

 

 

                                      -8-

 

 

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         Commencement Date with respect to the Second Floor Premises and on the

         Third Floor Premises Rent Commencement Date with respect to the Third

         Floor Premises, respectively, and thereafter monthly, in advance, on

         the first day of each and every calendar month during the Original

         Term, a sum equal to one twelfth (1/12th) of the applicable Annual

         Fixed Rent (sometimes hereinafter referred to as "fixed rent") and (b)

         on the Commencement Date and thereafter monthly, in advance, on the

         first day of each and every calendar month during the Original Term, a

         sum equal to one twelfth (1/12th) of $1.00 per annum for each square

         foot of Rentable Floor Area of Tenant's Space for tenant electricity

         subject to escalation as provided in Section 2.8 and (2) on the first

         day of each and every calendar month during the extension option

         period (if exercised), a sum equal to (a) one twelfth (1/12th) of the

         Annual Fixed Rent as determined in Section 2.4.1 for the extension

         option period plus (b) then applicable monthly electricity charges

         (subject to escalation for electricity as provided in Section 2.8

         hereof). Until notice of some other designation is given, fixed rent

         and all other charges for which provision is herein made shall be paid

         by remittance to or for the order of Boston Properties Limited

         Partnership, Agents at P.O. Box 3557, Boston, Massachusetts

         02241-3557, and all remittances received by Boston Properties Limited

         Partnership, as Agents as aforesaid, or by any subsequently designated

         recipient, shall be treated as payment to Landlord.

 

         Annual Fixed Rent for any partial month shall be paid by Tenant to

          Landlord at such rate on a pro rata basis, and, if the Second Floor

         Premises Rent Commencement Date and/or the Third Floor Premises Rent

         Commencement Date are a day other than the first day of a calendar

         month, the first payment of Annual Fixed Rent which Tenant shall make

         to Landlord shall be a payment equal to a proportionate part of such

         monthly Annual Fixed Rent for the partial month from the Second Floor

         Premises Rent Commencement Date and/or the Third Floor Premises Rent

         Commencement Date, as applicable, to the first day of the succeeding

         calendar month.

 

         Additional Rent payable by Tenant on a monthly basis, as hereinafter

         provided, likewise shall be prorated, and the first payment on account

         thereof shall be determined in similar fashion but shall commence on

         the Commencement Date; and other provisions of this Lease calling for

         monthly payments shall be read as incorporating this undertaking by

         Tenant.

 

         Notwithstanding that the payment of Annual Fixed Rent payable by Tenant

         to Landlord with respect to the Second Floor Premises shall not

         commence until the Second Floor Premises Rent Commencement Date and

         with respect to the Third Floor Premises shall not commence until the

         Third Floor Premises Rent Commencement Date, respectively, Tenant shall

         be subject to, and shall comply with, all other provisions of this

         Lease as and at the times provided in this Lease.

 

         The Annual Fixed Rent and all other charges for which provision is

         herein made shall be paid by Tenant to Landlord, without offset,

         deduction or abatement except as otherwise specifically set forth in

         this Lease.

 

 

                                      -9-

 

 

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2.6       OPERATING EXPENSES.

         ------------------

 

         "Landlord's Operating Expenses" means the cost of operation of the

         Building and the Site which shall exclude costs of special services

         rendered to tenants (including Tenant) for which a separate charge is

         made, but shall include, without limitation, the following: premiums

         for insurance carried with respect to the Building and the Site

         (including, without limitation, liability insurance, insurance against

         loss in case of fire or casualty and insurance of monthly installments

         of fixed rent and any Additional Rent which may be due under this Lease

         and other leases of space in the Building for not more than 12 months

         in the case of both fixed rent and Additional Rent and if there be any

         first mortgage of the Property, including such insurance as may be

         required by the holder of such first mortgage); compensation and all

         fringe benefits, worker's compensation insurance premiums and payroll

         taxes paid to, for or with respect to all persons engaged in the

         operating, maintaining or cleaning of the Building or Site, water,

         sewer, electric, gas, oil and telephone charges (excluding utility

         charges separately chargeable to tenants for additional or special

         services); cost of building and cleaning supplies and equipment; cost

         of maintenance, cleaning and repairs (other than repairs directly

         chargeable to other tenants or not properly chargeable against income

         or reimbursed from contractors under guarantees); cost of snow removal

         and care of landscaping; payments under service contracts with

         independent contractors; 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, cleaning and maintenance of the Building and the Site and

         properly chargeable against income, provided, however, there shall be

         included (a) depreciation for capital expenditures made by Landlord (i)

         to reduce Landlord's Operating Expenses if Landlord shall have

         reasonably determined that the annual reduction in Landlord's Operating

         Expenses shall exceed depreciation therefor or (ii) to comply with

         applicable laws, rules, regulations, requirements, statutes,

         ordinances, by-laws and court decisions of all public authorities which

         are now or hereafter in force; plus (b) in the case of both (i) and

         (ii) an interest factor, reasonably determined by Landlord, as being

         the interest rate then charged for long term mortgages by institutional

         lenders on like properties within the locality in which the Building is

         located; depreciation in the case of both (i) and (ii) shall be

         determined by dividing the original cost of such capital expenditure by

         the number of years of useful life of the capital item acquired and the

         useful life shall be reasonably determined by Landlord in accordance

         with generally accepted accounting principles and practices in effect

         at the time of acquisition of the capital item.

 

         "Tenant's Share" shall mean 17.85%.

 

         "Operating Expenses Allocable to the Premises" shall mean Tenant's

         Share of Landlord's Operating Expenses for and pertaining to the

         Building and the Site.

 

         "Base Operating Expenses" shall mean Landlord's Operating Expenses for

         calendar year 2005 (that is, the period beginning January 1, 2005 and

         ending December 31, 2005). Base Operating Expenses shall not include

         market-wide cost increases due to extraordinary circumstances, included

         but not limited to Force Majeure (as defined in Section 6.1),

         conservation surcharges, boycotts, strikes, embargoes or shortages.

 

 

                                      -10-

 

 

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         "Base Operating Expenses Allocable to the Premises" shall mean Tenant's

         Share of Base Operating Expenses.

 

          If with respect to any calendar year falling within the Term, or

         fraction of a calendar year falling within the Term at the beginning or

         end thereof, the Operating Expenses Allocable to the Premises for a

         full calendar year exceed Base Operating Expenses Allocable to the

         Premises or for any such fraction of a calendar year exceed the

         corresponding fraction of Base Operating Expenses Allocable to the

         Premises (such amount being hereinafter sometimes referred to as the

         "Operating Cost Excess") then, Tenant shall pay to Landlord, as

         Additional Rent, the amount of such excess. Such payments shall be made

         at the times and in the manner hereinafter provided in this Section

         2.6. (The Base Operating Expenses Allocable to the Premises do not

         include the $1.00 for tenant electricity to be paid by Tenant together

         with Annual Fixed Rent and for which provision is made in Section 2.5

         hereof, separate provision being made in Section 2.8 of this Lease for

         Tenant's share of increases in electricity costs.)

 

         Not later than one hundred and twenty (120) days after the end of the

         first calendar year or fraction thereof ending December 31 and of each

         succeeding calendar year during the Term or fraction thereof at the end

         of the Term, Landlord shall render Tenant a statement in reasonable

         detail and according to generally accepted accounting practices

         certified by a representative of Landlord, showing for the preceding

         calendar year or fraction thereof, as the case may be, Base Operating

         Expenses, Landlord's Operating Expenses and Operating Expenses

         Allocable to the Premises. Said statement to be rendered to Tenant

         shall also show for the preceding year or fraction thereof as the case

         may be the amounts of operating expenses already paid by Tenant as

         Additional Rent on account of the operating expenses and the amount of

         the Operating Cost Excess remaining due from, or overpaid by, Tenant

         for the year or other period covered by the statement. Within thirty

         (30) days after the date of delivery of such statement, Tenant shall

          pay to Landlord the balance of the amounts, if any, required to be paid

         pursuant to the above provisions of this Section 2.6 with respect to

         the preceding year or fraction thereof, or Landlord shall credit any

         amounts overpaid by Tenant against (i) monthly installments of fixed

         rent next thereafter coming due or (ii) any sums then due from Tenant

         to Landlord under this Lease (or refund such portion of the overpayment

         as aforesaid if the Term has ended and Tenant has no further obligation

         to Landlord).

 

         In addition, Tenant shall make payments monthly on account of Tenant's

         share of increases in Landlord's Operating Expenses anticipated for the

         then current year at the time and in the fashion herein provided for

         the payment of fixed rent. The amount to be paid to Landlord shall be

         an amount reasonably estimated annually by Landlord to be sufficient to

         cover, in the aggregate, a sum equal to the Operating Cost Excess for

         each calendar year during the Term.

 

         Notwithstanding the foregoing provisions, no decrease in Landlord's

         Operating Expenses shall result in a reduction of the amount otherwise

         payable by Tenant if and to the extent said decrease is attributable to

         vacancies in the Building rather than to any other causes.

 

 

                                      -11-

 

 

<Page>

 

 

2.7       REAL ESTATE TAXES.

         -----------------

 

         If with respect to any full Tax Year or fraction of a Tax Year falling

         within the Term, Landlord's Tax Expenses Allocable to the Premises (as

         hereinafter defined) for a full Tax Year exceed Base Taxes Allocable to

         the Premises or for any such fraction of a Tax Year exceed the

         corresponding fraction of Base Taxes Allocable to the Premises (such

         amount being hereinafter sometimes referred to as the "Tax Excess")

         then, on or before the thirtieth (30th) day following receipt by Tenant

         of the certified statement referred to below in this Section 2.7, then

         Tenant shall pay to Landlord, as Additional Rent, the amount of the Tax

         Excess. Not later than ninety (90) days after Landlord's Tax Expenses

         Allocable to the Premises are determined for the first such Tax Year or

         fraction thereof and for each succeeding Tax Year or fraction thereof

         during the Term, Landlord shall render Tenant a statement in reasonable

         detail certified by a representative of Landlord showing for the

         preceding year or fraction thereof, as the case may be, real estate

         taxes on the Building and the Site and abatements and refunds of any

         taxes and assessments. Expenditures for legal fees and for other

         expenses incurred in seeking the tax refund or abatement may be charged

         against the tax refund or abatement before the adjustments are made for

         the Tax Year. Said statement to be rendered to Tenant shall also show

         for the preceding Tax Year or fraction thereof as the case may be the

         amounts of real estate taxes already paid by Tenant as Additional Rent,

         and the amount of real estate taxes remaining due from, or overpaid by,

         Tenant for the year or other period covered by the statement. Within

         thirty (30) days after the date of delivery of the foregoing statement,

         Tenant shall pay to Landlord the balance of the amounts, if any,

         required to be paid pursuant to the above provisions of this Section

         2.7 with respect to the preceding Tax Year or fraction thereof, or

         Landlord shall credit any amounts due from it to Tenant pursuant to the

         provisions of this Section 2.7 against (i) monthly installments of

         fixed rent next thereafter coming due or (ii) any sums then due from

         Tenant to Landlord under this Lease (or refund such portion of the

         over-payment as aforesaid if the Term has ended and Tenant has no

         further obligation to Landlord).

 

         In addition, payments by Tenant on account of increases in real estate

         taxes anticipated for the then current year shall be made monthly at

         the time and in the fashion herein provided for the payment of fixed

         rent. The amount so to be paid to Landlord shall be an amount

         reasonably estimated by Landlord to be sufficient to provide Landlord,

         in the aggregate, a sum equal to Tenant's share of such increases, at

         least ten (10) days before the day on which such payments by Landlord

         would become delinquent.

 

         To the extent that real estate taxes shall be payable to the taxing

         authority in installments with respect to periods less than a Tax Year,

         the foregoing statement shall be rendered and payments made on account

         of such installments. Notwithstanding the foregoing provisions, no

         decrease in Landlord's Tax Expenses with respect to any Tax Year shall

         result in a reduction of the amount otherwise payable by Tenant if and

         to the extent said decrease is attributable to vacancies in the

         Building or partial completion of the Building rather than to any other

         causes.

 

 

                                      -12-

 

 

<Page>

 

 

         Terms used herein are defined as follows:

 

         (i)    "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.

 

         (ii)   "Tenant's Tax Share" means 18.79%.

 

         (iii) "Landlord's Tax Expenses Allocable to the Premises" shall mean

               Tenant's Tax Share of Landlord's Tax Expenses.

 

         (iv)   "Landlord's Tax Expenses" with respect to any Tax Year means the

               aggregate real estate taxes on the Building and Site with respect

               to that Tax Year, reduced by any abatement receipts with respect

               to that Tax Year.

 

         (v)    "Base Taxes" means Landlord's Tax Expenses (hereinbefore defined)

               for fiscal tax year 2006 (that is, the period beginning July 1,

               2005 and ending June 30, 2006).

 

         (vi)   "Base Taxes Allocable to the Premises" means Tenant's Tax Share

               of Base Taxes.

 

         (vii) "Real estate taxes" means all taxes and special assessments of

               every kind and nature and user fees and other like fees assessed

               by any governmental authority on the Building or Site which the

               Landlord shall become obligated to pay because of or in

               connection with the ownership, leasing or operation of the Site,

               the Building and the Property (including, without limitation, if

               applicable the excise prescribed by Mass Gen Laws Chapter 121A,

               Section 10 and amounts in excess thereof paid to the Town of

               Lexington pursuant to agreement between Landlord and the Town)

               and reasonable expenses of and fees for any formal or informal

               proceedings for negotiation or abatement of taxes (collectively,

               "Abatement Expenses"), which Abatement Expenses shall be excluded

               from Base 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 late fees or penalties, and income, estate, succession,

               inheritance and transfer taxes; provided, however, that if at any

               time during the Term the present system of ad valorem taxation of

               real property shall be changed so that in lieu of, or in addition

               to, 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 Site 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 the jurisdiction in

               which the Property is located) measured by or based, in whole or

               in part, upon any such gross rents, then any and all of such

               taxes, assessments, levies or charges, to the extent so measured

                or based, shall be

 

 

                                      -13-

 

 

<Page>

 

 

               deemed to be included within the term "real estate taxes" but

               only to the extent that the same would be payable if the Site and

                Building were the only property of Landlord.

 

        (viii) If during the Lease Term the Tax Year is changed by applicable

               law to less than a full 12-month period, the Base Taxes and Base

               Taxes Allocable to the Premises shall each be proportionately

               reduced.

 

2.8       TENANT ELECTRICITY.

         ------------------

 

         The current cost of furnishing electricity to the base building

         components of the Building and the Site is approximately $1.36 per

         square foot of the Total Rentable Floor Area of the Building and the

         current cost of furnishing electricity to the tenant spaces in the

         Building is approximately $1.15 per square foot of the Total Rentable

         Floor Area of the Building. The costs of electricity consumption

         chargeable to the tenants of the Building are based on the costs

         charged to Landlord by the local utility company providing service to

         the Building and the Site and are passed through to the tenants without

         mark-up. If with respect to any calendar year falling within the Term

         or fraction of a calendar year falling within the Term at the beginning

         or end thereof, the cost of furnishing electricity to the Building and

         the Site, including common areas and facilities and space occupied by

         tenants, (but expressly excluding utility charges separately chargeable

         to tenants for additional or special services) for a full calendar year

         exceeds $1.00 per square foot of Rentable Floor Area of the Building,

         or for any such fraction of a calendar year exceeds the corresponding

         fraction of $1.00 per square foot of Rentable Floor Area of the

         Building, then Tenant shall pay to Landlord, as Additional Rent, on or

         before the thirtieth (30th) day following receipt by Tenant of the

         statement referred to below in this Section 2.8, its proportionate

         share of the amount of such excess (i.e. the same proportion of such

         excess as the Rentable Floor Area of Tenant's Space bears to the Total

         Rentable Floor Area of the Building). In no event shall Tenant be

         responsible for any increases in the cost of electricity caused by

         another tenant's excessive use. Payments by Tenant on account of such

         excess shall be made monthly at the time and in the fashion herein

         provided for the payment of Annual Fixed Rent. The amount so to be paid

         to Landlord shall be an amount from time to time reasonably estimated

         by Landlord to be sufficient to cover, in the aggregate, a sum equal to

         such excess for each calendar year during the Term. If the Landlord

         shall reasonably determine that the cost of electricity furnished to

         the Tenant at the Premises exceeds the amount being paid under Sections

         2.5 and 2.8, then the Landlord may charge the Tenant for such excess

         and the Tenant shall promptly pay the same upon billing therefor.

 

         Not later than ninety (90) days after the end of the first calendar

         year or fraction thereof ending December 31 and of each succeeding

         calendar year during the Term or fraction thereof at the end of the

         Term, Landlord shall render Tenant a reasonably detailed accounting

         certified by a representative of Landlord showing for the preceding

         calendar year, or fraction thereof, as the case may be, the costs of

         furnishing electricity to the Building. Said statement to be rendered

         to Tenant also shall show for the preceding year or fraction thereof,

         as the case may be, the amount already paid by Tenant on account of

         electricity, and the amount remaining due from, or overpaid by, Tenant

         for the year or

 

 

                                      -14-

 

 

<Page>

 

 

         other period covered by the statement. Within thirty (30) days after

         the date of the delivery of such statement, Tenant shall pay to

         Landlord the balance of the amounts, if any required to be paid

         pursuant to the above provisions of this Section 2.8 with respect to

         the preceding year, or fraction thereof, or Landlord shall credit any

         amounts due from it to Tenant pursuant to the above provisions of this

         Section 2.8 against monthly installments of Annual Fixed Rent or

         Additional Rent next thereafter coming due unless the Lease Term has

         expired and Tenant has no other or further obligations to Landlord, in

         which case Landlord shall promptly refund such amount to Tenant.

 

                                   ARTICLE III

                                   -----------

 

                       CONDITION OF PREMISES; ALTERATIONS

                       ----------------------------------

 

3.1       CONDITION OF PREMISES.

         ---------------------

 

         Tenant shall accept the Premises in their As-Is condition without any

         obligation on the Landlord's part to perform any additions,

         alterations, improvements, demolition or other work therein or

         pertaining thereto.

 

3.2       QUALITY AND PERFORMANCE OF WORK.

         -------------------------------

 

         All construction work required or permitted by this Lease shall be done

         in a good and workmanlike manner and in compliance with all applicable

         laws, ordinances, rules, regulations, statutes, by-laws, court

         decisions, and orders and requirements of all public authorities

         ("Legal Requirements") and all Insurance Requirements (as defined in

         Section 5.14 hereof). All of Tenant's work shall be coordinated with

         any work being performed by or for Landlord and in such manner as to

         maintain harmonious labor relations. Each party may inspect the work of

         the other at reasonable times and shall promptly give notice of

         observed defects. Each party authorizes the other to rely in connection

         with design and construction upon approval and other actions on the

         party's behalf by any Construction Representative of the party named in

         Section 1.1 or any person hereafter designated in substitution or

         addition by notice to the party relying. Except to the extent to which

         Tenant shall have given Landlord notice of respects in which Landlord

         has not performed Landlord's construction obligations under this

         Article III (if any) (i) not later than the end of the sixth (6th) full

         calendar month next beginning after the Commencement Date with respect

         to the heating, ventilating and air conditioning systems servicing the

         Premises, and (ii) not later than the third (3rd) full calendar month

         next beginning after the Commencement Date with respect to Landlord's

         construction obligations under this Article III not referenced in (i)

         above, Tenant shall be deemed conclusively to have approved Landlord's

         construction and shall have no claim that Landlord has failed to

         perform any of Landlord's obligations under this Article III (if any).

         Landlord agrees to correct or repair at its expense items which are

         then incomplete or do not conform to the work contemplated under the

         Plans and as to which, in either case, Tenant shall have given notice

         to Landlord, as aforesaid.

 

 

                                      -15-

 

 

<Page>

 

 

3.3       SPECIAL ALLOWANCE.

         -----------------

 

          Landlord shall provide to Tenant a special allowance equal to the

         product of (i) $6.00 and (ii) the Rentable Floor Area of the Premises

         (the "Tenant Allowance"). The Tenant Allowance shall be used and

         applied by Tenant solely on account of the cost of work performed by or

         on behalf of Tenant ("Tenant's Work"), which such Tenant's Work shall

         be performed in accordance with the terms of this Lease. Provided that

         the Tenant (i) has opened for business in the Premises, (ii) has

         completed all of such Tenant's Work in accordance with the terms of

         this Lease, has paid for all of such Tenant's Work in full and has

         delivered to Landlord lien waivers from all persons who might have a

          lien as a result of such work, in the recordable forms attached hereto

         as Exhibit F, (iii) has delivered to Landlord its certificate

         specifying the cost of such Tenant's Work and all contractors,

         subcontractors and supplies involved with Tenant's Work, together with

         evidence of such cost in the form of paid invoices, receipts and the

         like, (iv) has satisfied the requirements of (i) through (iii) above

         and made request for such payment on or before May 1, 2006, (v) is not

         otherwise in default under this Lease, and (vi) there are no liens

         (unless bonded to the reasonable satisfaction of Landlord) against

         Tenant's interest in the Lease or against the Building or the Site

          arising out of Tenant's Work or any litigation in which Tenant is a

         party, then within thirty (30) days after the satisfaction of the

         foregoing conditions, the Landlord shall pay to the Tenant the lesser

         of the amount of such costs so certified or the amount of the Tenant

         Allowance. Notwithstanding the foregoing, Tenant shall have the option

         to request Landlord to make two separate disbursements of the Tenant

         Allowance (one prior to final completion of the Tenant's Work and one

         upon completion of the same), provided that in the case of the request

         made prior to final completion (1) Tenant has satisfied the

         requirements of items (ii) through (vi) above with respect to that

         portion of the Tenant's Work completed prior to the date of the request

         and (2) the disbursement requested by Tenant equals $21,832.00 or more.

         For the purposes hereof, the cost to be so reimbursed by Landlord shall

         include (x) the cost of leasehold improvements, engineering fees,

         architectural fees and third-party supervision or management fees and

         (y) up to $21,832.00 towards the cost of Tenant's voice and data

         cabling, personal property, trade fixtures or trade equipment, moving

         expenses or any so-called soft costs.

 

         Notwithstanding the foregoing, Landlord shall be under no obligation to

         apply any portion of the Tenant Allowance for any purposes other than

         as provided in this Section 3.4, nor shall Landlord be deemed to have

         assumed any obligations, in whole or in part, of Tenant to any

         contractors, subcontractors, suppliers, workers or materialmen.

         Further, in no event shall Landlord be required to make application of

         any portion of the Tenant Allowance on account of any supervisory fees,

         overhead, management fees or other payments to Tenant, or any partner

         or affiliate of Tenant. In the event that such cost of Tenant's Work is

         less than the Tenant Allowance, Tenant shall not be entitled to any

         payment or credit nor shall there be any application of the same toward

         Annual Fixed Rent or Additional Rent owed by Tenant under this Lease.

 

 

                                      -16-

 

 

<Page>

 

 

                                   ARTICLE IV

                                   ----------

 

                 LANDLORD'S COVENANTS; INTERRUPTIONS AND DELAYS

                 ----------------------------------------------

 

4.1       LANDLORD COVENANTS:

         ------------------

 

         4.1.1     SERVICES FURNISHED BY LANDLORD.

                  ------------------------------

 

                  To furnish services, utilities, facilities and supplies set

                  forth in Exhibit C equal to those customarily provided by

                  landlords in high quality buildings in the Boston West

                  Suburban Market subject to escalation reimbursement in

                  accordance with Section 2.6.

 

         4.1.2     ADDITIONAL SERVICES AVAILABLE TO TENANT.

                  ---------------------------------------

 

                  To furnish, at Tenant's expense, reasonable additional

                  Building operation services which are usual and customary in

                  similar office buildings in the Boston West Suburban Market

                  upon reasonable advance request of Tenant at reasonable and

                  equitable rates from time to time established by Landlord.

                  Tenant agrees to pay to Landlord, as Additional Rent, the

                  reasonable cost of any such additional Building services

                  requested by Tenant and for the reasonable cost of any

                  additions, alterations, improvements or other work performed

                  by Landlord in the Premises at the request of Tenant within

                  thirty (30) days after being billed therefor.

 

         4.1.3     ROOF, EXTERIOR WALL, FLOOR SLAB AND COMMON FACILITY REPAIRS.

                  -----------------------------------------------------------

 

                  Except for (a) normal and reasonable wear and use and (b)

                  damage caused by fire and casualty and by eminent domain, and

                  except as otherwise provided in Article VI and subject to the

                  escalation provisions of Section 2.6, (i) to make such repairs

                  to the structural portions of the Building (including but not

                   limited to the roof, exterior walls and floor slabs) and to

                  the common areas and facilities as may be necessary to keep

                  them in serviceable condition and (ii) to maintain the

                  Building (exclusive of Tenant's responsibilities under this

                  Lease) in a first class manner comparable to the maintenance

                  of similar properties in the Boston West Suburban Market.

 

         4.1.4     DOOR SIGNS.

                  ----------

 

                  To provide and install, at Landlord's expense, letters or

                  numerals on the exterior doors to the Premises to identify

                  Tenant's official name and Building address; all such letters

                  and numerals shall be in the building standard graphics and no

                  others shall be used or permitted on the Premises.

 

 

                                      -17-

 

 

<Page>

 

 

4.2       INTERRUPTIONS AND DELAYS IN SERVICES 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, including without limitation the causes set forth in Section

         3.2 hereof as being reasonably beyond Landlord's control, Landlord

         shall not be liable to Tenant therefor, nor, except as expressly

         otherwise provided in Article VI, shall Tenant be entitled to any

         abatement or reduction of rent by reason thereof, or right to terminate

         this Lease, 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.

 

         In the event that the electrical, heating, ventilating, air

         conditioning, or all elevator service to the Premises shall be shut

         down for more than five (5) full and consecutive business days, but

         only as a result of causes which are covered by Landlord's loss of

         rentals insurance, then, Tenant shall be entitled to an abatement of

          Annual Fixed Rent equal to the "Insurance Amount" (hereinafter

         defined). The "Insurance Amount" shall be an amount equal to the

         payment actually received by Landlord (but only allocable to and on

         account of the Premises) for such shut down of electricity service to

         the Premises from Landlord's insurance carrier providing such loss of

         rents insurance less the amount of any deductible contained in such

         loss of rents insurance coverage. Notwithstanding anything herein

         contained to the contrary, in no event shall any of the events referred

         to in this Section give rise to a claim in Tenant's favor that such

         failure constitutes actual or constructive, total or partial, eviction

          from the Premises.

 

 

                                      -18-

 

 

<Page>

 

 

                                    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 (except as otherwise provided

         in Exhibit C) and, further, as Additional Rent, all charges for

         additional services rendered pursuant to Section 4.1.2.

 

5.2       REPAIR AND YIELD UP.

          -------------------

 

         Except as otherwise provided in Article VI and Section 4.1.3, to keep

         the Premises in good order, repair and condition, damage by casualty

         and reasonable wear and tear only excepted, and all glass in windows

         (except glass in exterior walls 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 similar type and

         quality as that injured or broken, damage by fire or taking under the

         power of eminent domain only excepted, and at the expiration or

         termination of this Lease peaceably to yield up the Premises all

         construction, work, improvements, and all alterations and additions

         thereto in good order, repair and condition, reasonable wear and tear

         only excepted, first removing all goods and effects of Tenant and, to

         the extent specified by Landlord by notice to Tenant given at the time

          Landlord approves Tenant's plans for the installation of the same that

         removal will be required upon the expiration or earlier termination of

         the Lease Term, the wiring for Tenant's computer, telephone and other

         communication systems and equipment whether located in the Premises or

         in any other portion of the Building, including all risers and all

         alterations and additions made by Tenant and all partitions. Tenant

         shall repair any damage caused by such removal and shall restore the

         Premises and leave them clean and neat. Tenant shall not permit or

         commit any waste, and Tenant shall be responsible for the cost of

         repairs which may be made necessary by reason of damage to common areas

         in the Building or to the Site caused by Tenant, Tenant's agents,

         contractors, employees, sublessees, licensees, concessionaires or

         invitees.

 

5.3       USE.

         ---

 

         Continuously from the commencement of the Term, to use and occupy the

         Premises for the Permitted Use only, and not to injure or deface the

         Premises, Building, the Site or any other part of the Complex nor to

         permit in the Premises or on the Site any auction sale, vending machine

         (except for two (2) vending machines exclusively for use by Tenant's

         employees, one per on each floor occupied by Tenant; provided, however,

         that (i) Landlord shall have the right to approve the location of each

          such vending machine and (ii) Tenant shall be required to remove the

         vending machines upon the expiration or earlier termination of this

         Lease and repair any damage to the Premises caused by their

         installation and removal), or inflammable fluids or chemicals, or

         nuisance, or the emission from the Premises of any objectionable noise

         or odor, nor to permit in the Premises anything which will in any way

         result in the leakage of fluid or the growth of mold, and not to use or

         devote the Premises or any part thereof for any purpose other than the

         Permitted Uses, nor for any use thereof which is inconsistent with

         maintaining the Building as a first class office building in the

          quality of its maintenance, use and occupancy, or which is improper,

         offensive, contrary to law or ordinance or liable to render necessary

         any alteration or addition to the Building. Further, (i) Tenant shall

         not,

 

 

                                       -19-

 

 

<Page>

 

 

         nor shall Tenant permit its employees, invitees, agents, independent

         contractors, contractors, assignees or subtenants to, keep, maintain,

         store or dispose of (into the sewage or waste disposal system or

         otherwise) or engage in any activity which might produce or generate

         any substance which is or may hereafter be classified as a hazardous

         material, waste or substance (collectively "Hazardous Materials"),

         under federal, state or local laws, rules and regulations, including,

         without limitation, 42 U.S.C. Section 6901 et seq., 42 U.S.C. Section

         9601 et seq., 42 U.S.C. Section 2601 et seq., 49 U.S.C. Section 1802

         et seq. and Massachusetts General Laws, Chapter 21E and the rules and

         regulations promulgated under any of the foregoing, as such laws,

         rules and regulations may be amended from time to time (collectively

         "Hazardous Materials Laws"), (ii) Tenant shall immediately notify

         Landlord of any incident in, on or about the Premises, the Building or

         the Site that would require the filing of a notice under any Hazardous

         Materials Laws, (iii) Tenant shall comply and shall cause its

         employees, invitees, agents, independent contractors, contractors,

         assignees and subtenants to comply with each of the foregoing and (iv)

         Landlord shall have the right upon forty-eight (48) hours notice

         (except in the event of an emergency) to make such inspections

         (including testing) as Landlord shall reasonably determine are

         necessary from time to time to determine that Tenant is complying with

         the foregoing.

 

5.4       OBSTRUCTIONS; ITEMS VISIBLE FROM EXTERIOR; RULES AND REGULATIONS.

         ----------------------------------------------------------------

 

         Not to obstruct in any manner any portion of the Building not hereby

         leased or any portion thereof or of the Site used by Tenant in common

         with others; 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 all 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 Site 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.

 

5.5       SAFETY APPLIANCES.

         -----------------

 

         To keep the Premises equipped with all safety appliances required by

         any public authority because of any use made by Tenant other than for

         Tenant's Permitted 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 Use.

 

5.6       ASSIGNMENT; SUBLEASE.

         --------------------

 

          Except as otherwise expressly provided herein, Tenant covenants and

         agrees that it shall not assign, mortgage, pledge, hypothecate or

         otherwise transfer this Lease and/or Tenant's interest in this Lease or

         sublet (which term, without limitation, shall include granting of

         concessions, licenses or the like) the whole or any part of the

         Premises. Any assignment, mortgage, pledge, hypothecation, transfer or

         subletting not expressly

 

 

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         permitted in or consented to by Landlord under Sections 5.6.1-5.6.6

         shall be void, ab initio; shall be of no force and effect; and shall

         confer no rights on or in favor of third parties. In addition,

         Landlord shall be entitled to seek specific performance of or other

         equitable relief with respect to the provisions hereof.

 

         5.6.1 Notwithstanding the provisions of Section 5.6 above and the

               provisions of Section 5.6.2, 5.6.3 and 5.6.5 below, Tenant shall

               have the right to assign this Lease or to sublet the Premises (in

               whole or in part) to any parent or subsidiary corporation of

               Tenant or to any corporation into which Tenant may be converted

               or with which it may merge, provided that the entity to which

               this Lease is so assigned or which so sublets the Premises has a

               credit worthiness (e.g. assets on a pro forma basis using

               generally accepted accounting principles consistently applied and

               using the most recent financial statements) which is the same or

               better than Tenant as of the date of this Lease. If any parent or

                subsidiary corporation of Tenant to which this Lease is assigned

               or the Premises sublet (in whole or in part) shall cease to be

               such a parent or subsidiary corporation, such cessation shall be

               considered an assignment or subletting requiring Landlord's

               consent, which consent shall not be unreasonably withheld,

               delayed or conditioned. Any such assignment or subletting shall

               be subject to the provisions of Section 5.6.4 and Section 5.6.6

               below.

 

         5.6.2 Notwithstanding the provisions of Section 5.6 above, in the

               event Tenant desires to assign this Lease or to sublet the

               Premises (in whole or in part), Tenant shall give Landlord a

               Proposed Transfer Notice (as defined in Section 5.6.4 hereof) and

               Landlord shall have the right at its sole option, to be exercised

               within fifteen (15) days after receipt of Tenant's Proposed

                Transfer Notice (the "Acceptance Period"), to terminate this

               Lease as of a date specified in a notice to Tenant, which date

               shall not be earlier than sixty (60) days nor later than one

               hundred and twenty (120) days after Landlord's notice to Tenant;

               provided, however, that upon the termination date as set forth in

               Landlord's notice, all obligations relating to the period after

               such termination date (but not those relating to the period

               before such termination date) shall cease and promptly upon being

               billed therefor by Landlord, Tenant shall make final payment of

               all rent and Additional Rent due from Tenant through the

               termination date. Notwithstanding the foregoing, in the event

               that Tenant shall propose to sublease a portion of the Premises,

               Landlord shall only have the right to so terminate this Lease

               with respect to the portion of the Premises which Tenant proposes

               to sublease (the "Terminated Portion of the Premises") and from

               and after the termination date the Rentable Floor Area of the

               Premises shall be reduced to the rentable floor area of the

               remainder of the Premises and the definition of Rentable Floor

               Area of the Premises shall be so amended and after such

               termination all references in this Lease to the "Premises" or the

               "Rentable Floor Area of the Premises" shall be deemed to be

               references to the remainder of the Premises and accordingly

               Tenant's payments for Annual Fixed Rent, operating costs, real

               estate taxes and electricity shall be reduced on a pro rata basis

               to reflect the size of the remainder of the Premises.

 

 

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               In the event that Landlord elects to terminate this Lease as

               aforesaid, Tenant shall have the right upon written notice

               delivered to Landlord within fifteen (15) days from receipt of

               Landlord's termination notice, to rescind its Proposed Transfer

               Notice, at which point Landlord's termination notice shall be

               deemed null and void and this Lease shall continue in full force

               and effect.

 

               In the event that Landlord shall not exercise its termination

                rights as aforesaid, or shall fail to give any or timely notice

               pursuant to this Section the provisions of Sections 5.6.3-5.6.6

               shall be applicable. This Section 5.6.2 shall not be applicable

               to an assignment or sublease pursuant to Section 5.6.1.

 

         5.6.3 Notwithstanding the provisions of Section 5.6 above, but subject

               to the provisions of this Section 5.6.3 and the provisions of

               Sections 5.6.4, 5.6.5 and 5.6.6 below, in the event that Landlord

               shall not have exercised the termination right as set forth in

               Section 5.6.2, or shall have failed to give any or timely notice

               under Section 5.6.2, then for a period of ninety (90) days (i)

               after the receipt of Landlord's notice stating that Landlord does

               not elect the termination right, or (ii) after the expiration of

               the Acceptance Period in the event Landlord shall not give any or

                timely notice pursuant to Section 5.6.2, as the case may be,

               Tenant shall have the right to assign this Lease or sublet the

               Premises in accordance with the Proposed Transfer Notice given as

               provided in Section 5.6.4 provided that, in each instance, Tenant

               first obtains the express prior written consent of Landlord,

               which consent shall not be unreasonably withheld or delayed.

               Without limiting the foregoing standard, Landlord shall not be

               deemed to be unreasonably withholding its consent to such a

               proposed assignment or subleasing if:

 

               (a)   if Landlord has comparable space available for lease in the

                    Building, the proposed assignee or subtenant is a tenant in

                    the Building or is in active negotiation with Landlord for

                    premises in the Building, or

 

               (b)   the proposed assignee or subtenant is not of good character

                    and reputation or is not of a character consistent with the

                    operation of a first class office building (by way of

                    example Landlord shall not be deemed to be unreasonably

                     withholding its consent to an assignment or subleasing to

                    any governmental or quasi-governmental agency which is open

                    to the public), or

 

               (c)   the proposed assignee does not possess adequate financial

                    capability to perform the Tenant obligations as and when due

                    or required or the proposed subtenant does not possess

                    adequate financial capability to perform the subtenant

                    obligations under the sublease as and when due or required,

                    or

 

               (d)   the assignee or subtenant proposes to use the Premises (or

                    part thereof) for a purpose other than the purpose for which

                     the Premises may be used as stated in Section 1.1 hereof, or

 

 

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               (e)   the character of the business to be conducted or the

                    proposed use of the Premises by the proposed subtenant or

                    assignee shall (i) be likely to increase Landlord's

                    Operating Expenses beyond that which Landlord now incurs for

                    use by Tenant; (ii) be likely to increase the burden on

                     elevators or other Building systems or equipment over the

                    burden prior to such proposed subletting or assignment; or

                    (iii) violate or be likely to violate any provisions or

                    restrictions contained herein relating to the use or

                    occupancy of the Premises, or

 

               (f)   there shall be existing an Event of Default (defined in

                    Section 7.1), or

 

               (g)   any part of the rent payable under the proposed assignment

                    or sublease shall be based in whole or in part on the income

                    or profits derived from the Premises or if any proposed

                    assignment or sublease shall potentially have any adve