INDENTURE OF LEASE

<Page>

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:

<Table>

<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

<Page>

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

-2-

<Page>

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-

<Page>

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

</Table>

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.

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

<Table>

<S> <C> <C>

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

-4-

<Page>

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

-5-

<Page>

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.

-6-

<Page>

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-

<Page>

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-

<Page>

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-

<Page>

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-

<Page>

"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

-20-

<Page>

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.

-21-

<Page>

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

-22-

<Page>

(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