AGREEMENT FOR PURCHASE OF REAL ESTATE

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EXHIBIT 10.1

AGREEMENT FOR PURCHASE OF

REAL ESTATE

THIS AGREEMENT FOR PURCHASE OF REAL ESTATE (this "Agreement") is made

and entered into as of the 15th day of April, 2005, by and between The Lyme

Timber Company, a New Hampshire Limited Partnership, having offices at 23 South

Main Street, 3rd Floor, Hanover, New Hampshire 03755 ("Seller"), and Biomed

Realty, L.P., a Maryland limited partnership, having offices at 17140 Bernardo

Center Drive, Suite 222, San Diego, California 92128 ("Purchaser"). In addition

to Seller and Purchaser, this Agreement contains certain provisions enumerating

the rights and obligations of the Joint Ventures (as defined below). The

agreement of the Joint Ventures to accept such rights and be bound by such

obligations is addressed in Section 8 hereof.

RECITALS

A. Seller and its wholly-owned subsidiaries set forth on Schedule 1 are

the owners of, or own interests in, the Properties set forth opposite their

names on Schedule 1. Additionally, Seller owns certain interests in joint

ventures (the "Joint Ventures") that in turn are the owners of, or whose

subsidiaries are the owners of, the Properties set forth opposite their names on

Schedule 1. Each such wholly-owned subsidiary of Seller, Joint Venture, or

subsidiary of a Joint Venture set forth on Schedule 1 is hereinafter referred to

as a "Subsidiary" and collectively as "Subsidiaries".

B. Seller desires to sell, and/or cause its Subsidiaries to sell, the

Properties set forth opposite their names on Schedule 1 to Purchaser by deed

conveyance of such Properties, and Purchaser desires to so purchase such

Properties as specified on Schedule 1 from Seller or its Subsidiaries, as

applicable, each upon and subject to the terms and conditions of this Agreement.

C. Section 15 contains a table of defined terms, Section 16 contains a

list of Exhibits and Section 17 contains a list of Schedules with respect to

this Agreement.

NOW THEREFORE, in consideration of the terms, covenants and conditions

contained in this Agreement, and other good and valuable consideration, the

receipt and sufficiency of which are hereby acknowledged, Seller, the Joint

Ventures and Purchaser agree as follows:

1. PURCHASE AND SALE OF PROPERTY

Subject to the terms and conditions of this Agreement (including,

without limitation, Section 13(B)), Seller shall sell and convey, or shall cause

its Subsidiaries to sell and convey, and Purchaser shall purchase, the

Properties as specified on Schedule 1 opposite the names of the Seller and its

Subsidiaries. Each parcel of property set forth on Schedule 1 (each, a

"Property" and collectively, the "Properties") shall consist of:

(A) all right, title and interest of Seller or its Subsidiaries, as

applicable, in and to those certain tracts of real estate described on the

attached Schedule 1, upon which are situated

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certain buildings, garages or other improvements, which real estate is legally

described in the attached Schedule 1(A), together with all and singular

easements, covenants, agreements, rights, privileges, tenements, hereditaments

and appurtenances thereunto now or hereafter belonging or appertaining thereto

(collectively, the "Land"); and

(B) all right, title and interest of Seller or its Subsidiaries, as

applicable, in and to any land lying in the bed of any street, alley, road or

avenue (whether open, closed or proposed) adjoining the Land or any of it (all

of the foregoing being included within the term "Land"); and

(C) all right, title and interest of Seller or its Subsidiaries, as

applicable, in and to all of the buildings, structures, fixtures, facilities,

installations and other improvements of every kind and description now or

hereafter located on the Land, including, without limitation, any and all

plumbing, air conditioning, heating, ventilating, mechanical, electrical and

other utility systems, parking lots and facilities, landscaping, roadways,

sidewalks, security devices, signs and light fixtures (collectively, the

"Improvements"; the Land and Improvements being collectively referred to as the

"Premises"); and

(D) all right, title and interest of Seller or its Subsidiaries, as

applicable, in and to the items of personal property now or hereafter located in

and used in connection with the operation, ownership or management of the

Premises, including the items of personal property set forth on Schedule 1(D)-1

attached to this Agreement (the "Personal Property"), but specifically excluding

(i) any items of personal property listed on Schedule 1(D)-2 (the "Excluded

Property") and (ii) any items of personal property owned or leased (from anyone

other than Seller) by Seller's property manager or any tenant at or on the

Premises, provided that Seller shall have thirty (30) days after the Closing

Date to remove any Excluded Property located at the Premises and Purchaser shall

reasonably cooperate with Seller in connection with such removals; and

(E) all right, title and interest of Seller or its Subsidiaries, as

applicable, in and to all existing surveys, blue prints, drawings, plans and

specifications (including, without limitation, structural, HVAC, mechanical and

plumbing plans and specifications) and other documentation for or with respect

to the Property; all marketing artwork and construction drawings concerning the

Property, in each case, to the extent available and in the possession and

control of Seller or its Subsidiaries, as applicable; all tenant lists and data,

correspondence with past, present and prospective tenants, vendors, suppliers,

utility companies and other third parties, booklets, manuals and promotional and

advertising materials concerning the Property or any part thereof, in each case,

to the extent available and in the possession and control of Seller or its

Subsidiaries, as applicable; and such other existing books, records and

documents (including, without limitation, those relating to ad valorem taxes and

leases) used solely in connection with the operation of the Property to the

extent available and in the possession and control of Seller or its

Subsidiaries, as applicable; all trade names and trade marks associated with any

Property or by which any Property is commonly known or designated (each, a

"Property Name"); provided, however, that (i) none of Seller, Joint Ventures or

any of their Subsidiaries makes any representations or warranties whatsoever

with respect to the Property Names and (ii) for the avoidance of doubt, Seller

and Purchaser each acknowledge that patents, trademarks, trade names, copyrights

or other intellectual property other than the Property Names

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(collectively, "Intellectual Property"), including, without limitation, the

trade names "Lyme," "Lyme Properties," and "Kendall Square" shall not be

transferred from Seller to Purchaser under this Agreement; and

(F) all right, title and interest of Seller or its Subsidiaries, as

applicable, in and to the leases affecting the Premises (the "Leases") and the

Other Documents affecting the Premises and the other intangible personal

property (other than Intellectual Property) now or hereafter owned by Seller or

its Subsidiaries, as applicable, and solely relating to the Property.

2. PURCHASE PRICE

(A) Purchase Price.

The total consideration to be paid by Purchaser to Seller and the Joint

Ventures for the Properties is Five Hundred Twenty-Four Million Dollars

($524,000,000) (the "Purchase Price"), which is allocated among the Properties

as indicated on the attached Schedule 1 (the amount allocated to each Property

on Schedule 1 being the "Allocated Purchase Price" for such Property).

Purchaser, Seller and the Joint Ventures agree that (i) the allocation of the

Purchase Price among the Properties set forth on Schedule 1 reflects Purchaser's

determination of the fair market value of each Property, and (ii) no portion of

the Purchase Price shall be allocated to the Personal Property. The Purchase

Price shall be paid as follows:

(B) Earnest Money.

(i) Upon the execution of this Agreement by Seller and

Purchaser, Purchaser shall either (a) deposit in an account (the "Escrow

Account") designated by the New York City office of the Title Insurer

("Escrowee") the sum of Two Million Dollars ($2,000,000) in immediately

available funds, or (b) deliver to Escrowee a Letter of Credit in the stated

amount of Two Million Dollars ($2,000,000) (such funds, together with any

interest earned thereon, net of investment costs, or such Letter of Credit, the

"Earnest Money"). Upon the expiration of the Due Diligence Date (as defined in

Section 13(B)), Purchaser shall either (x) deposit in the Escrow Account the

additional sum of Thirteen Million Dollars ($13,000,000) in immediately

available funds, or (y) deliver to Escrowee an additional Letter of Credit in

the stated amount of Thirteen Million Dollars ($13,000,000) or an amended and

restated Letter of Credit in the amount of Fifteen Million Dollars ($15,000,000)

(in which case, with respect to the amended and restated Letter of Credit the

Escrowee shall return the original Letter of Credit to Purchaser) (such funds,

together with any interest earned thereon, net of investment costs, or such

Letter of Credit, the "Second Deposit"), which Second Deposit shall become part

of the Earnest Money. The Earnest Money shall be held by Escrowee pursuant to

the escrow instructions in the form attached hereto as Exhibit A (the "Earnest

Money Escrow Instructions"). If at any time any portion of the Earnest Money is

not represented by a Letter of Credit, Escrowee shall invest such portion of the

Earnest Money in an interest-bearing savings account or short-term U.S. Treasury

Bills or similar cash-equivalent securities, as directed by Purchaser and

Seller. Any and all interest earned on the Earnest Money shall be reported to

Purchaser's federal tax identification number and shall become part of the

Earnest Money. "Letter of Credit" shall mean an irrevocable, unconditional,

transferable, clean sight draft letter of credit in a form reasonably acceptable

to Seller issued or confirmed for direct payment by a financial institution

acceptable

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to Seller, that expires no later than three (3) months after the Closing, in

favor of Seller entitling Seller to draw thereon based solely on a statement

purportedly executed by an officer of Seller stating that it has the right to

draw thereon.

(C) Notwithstanding anything herein to the contrary, if this Agreement

is terminated pursuant to Sections 4(B)(iv), 4(D), 4(F), 6(A), 8(A)(iii), 8(C),

8(E), 8(H), 8(I), 10(A)(ii) or 13(B), the Earnest Money shall be delivered by

the Escrowee to Purchaser. This Section 2(C) shall survive the termination of

this Agreement.

(i) If this Agreement is terminated pursuant to Section 10(C),

the Earnest Money shall be delivered by the Escrowee to an account or accounts

designated by Seller. This Section 2(C)(i) shall survive the termination of this

Agreement.

(ii) At the Closing, the Earnest Money shall be delivered by

the Escrowee to an account or accounts designated by Seller (subject to the next

sentence) as payment toward the Purchase Price. For convenience in determining

the Cash Balance, only interest earned through the fifth (5th) business day

prior to the scheduled Closing Date (even if such Closing Date should be

adjourned) shall be delivered to an account or accounts designated by Seller and

taken into account in determining the Cash Balance and the remaining interest

with respect to the Earnest Money shall be delivered to Purchaser.

(D) Cash Balance.

At the Closing, Purchaser shall pay to Seller (or such other parties as

directed by Seller) the Purchase Price less (i) the amount delivered to Seller

under Section 2(C)(ii), and (ii) the aggregate principal amount outstanding

under the Assumed Loans as of the Closing Date, such sum to be paid by wire

transfer of immediately available funds transferred to an account or accounts

designated by Seller in writing by notice received by Purchaser not less than

one (1) business day prior to the Closing Date, subject, however, to such

prorations and adjustments as are required by this Agreement (such amount to be

paid to Seller (or such other parties as directed by Seller), as adjusted, being

referred to as the "Cash Balance").

3. OPERATION OF PROPERTY THROUGH CLOSING

From the date of this Agreement through the Closing Date, Seller

covenants that (and, as applicable, Purchaser covenants that):

(A) Except as otherwise provided in this Section 3, Seller and the

Joint Ventures shall, or shall cause their respective Subsidiaries, as

applicable, to manage, operate and maintain the Properties in a manner

consistent with past practices. Seller and the Joint Ventures will not, and will

cause their respective Subsidiaries, as applicable, not to make any change in

their normal and customary billing practices or apply any security deposits

against rent delinquencies or other Lease defaults (other than for tenants who

either vacate their spaces or with whom Seller, the Joint Ventures or their

respective Subsidiaries engage in litigation) without notice to Purchaser.

(B) Without the prior written consent of Purchaser or except as

otherwise provided in this Section 3, Seller and the Joint Ventures shall not,

and shall cause their respective

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Subsidiaries, as applicable, not to sell, mortgage, pledge, hypothecate or

otherwise transfer or dispose of all or any part of the Properties (except for

(x) such items of tangible Personal Property as become obsolete, consumed or are

disposed of in the ordinary course of business, or (y) due to a Condemnation

(for which Section 6 shall govern)). Purchaser's consent to the actions

described in this Section 3(B) shall not be unreasonably withheld conditioned or

delayed, provided that (I) such consent shall be deemed given if Purchaser does

not respond within five (5) days after request for consent from Seller or a

Joint Venture, as applicable, and (II) any denial of consent shall be

accompanied by an explanation as to why such consent was denied.

(C) Without the prior written consent of Purchaser, Seller and the

Joint Ventures shall not, and shall cause their respective Subsidiaries, as

applicable, not to (i) terminate any Lease (except in the case of (x) a default

or to relocate a tenant and otherwise in the ordinary course of business or (y)

such Lease terminating by its terms) or (ii) modify, extend, amend or renew any

Lease or enter into any new Lease. Purchaser's consent to the actions described

in this Section 3(C) shall not be unreasonably withheld conditioned or delayed,

provided that (I) such consent shall be deemed given if Purchaser does not

respond within five (5) business days after request for consent from Seller or a

Joint Venture, as applicable, and (II) any denial of consent shall be

accompanied by an explanation as to why such consent was denied; provided,

however, Purchaser's denial of consent shall be considered reasonable if,

assuming the Closing were to occur, any action could jeopardize BioMed Realty

Trust, Inc., a Maryland corporation ("Purchaser's REIT Entity") status as a real

estate investment trust within the meaning of Sections 856 through 860 of the

Internal Revenue Code of 1986 (the "Code") or cause the Purchaser REIT Entity to

be in receipt of income that does not constitute "rent from real property"

within the meaning Section 856(d) of the Code. Notwithstanding the foregoing,

Purchaser approves of the proposed Lease amendments on Schedule 3(C) and Seller

or its applicable Subsidiary shall have the right, but not the obligation, to

enter into such Lease amendments without further consent of Purchaser at any

time prior to Closing. At Closing, Purchaser shall assume the obligations of

Seller, the Joint Ventures, and their respective Subsidiaries, as applicable,

under all of the Leases affecting the Properties that exist as of the Closing

(including the Leases that exist as of the date hereof (other than those that

expired or were duly terminated) and such Leases affecting the Properties that

are entered into, amended, modified or renewed after the date hereof not in

violation of this Agreement).

(D) Prior to the Closing Date, except as described in Sections

8(A)-8(C), without the prior written consent of Purchaser, Seller and the Joint

Ventures shall not, and shall cause their respective Subsidiaries, as

applicable, not to (i) terminate any of the Assumed Loan Documents or Other

Documents, except for such Assumed Loan Documents or Other Documents which

mature or expire by their terms prior to the Closing Date, (ii) modify, extend,

amend or renew any Assumed Loan Document or Other Document, or (iii) unless

otherwise required by the applicable lender and subject to Seller paying off any

financing with respect to any Property which is not an Assumed Loan, make any

payments other than regularly scheduled payments on the Assumed Loans.

Purchaser's consent to the actions described in this Section 3(D) shall not be

unreasonably withheld conditioned or delayed, provided that (I) such consent

shall be deemed given if Purchaser does not respond within five (5) business

days after request for consent from Seller or a Joint Venture, as applicable,

and (II) any denial of consent shall be accompanied by an explanation as to why

such consent was denied; provided, however, Purchaser's denial of consent shall

be considered reasonable if, assuming the Closing were to

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occur, any action could jeopardize Purchaser's REIT Entity's status as a real

estate investment trust within the meaning of Sections 856 through 860 of the

Code or cause the Purchaser REIT Entity to be in receipt of income that does not

constitute "rent from real property" within the meaning Section 856(d) of the

Code. At Closing, Purchaser shall assume the obligations of Seller, the Joint

Ventures, and their respective Subsidiaries, as applicable, under the Assumed

Loan Documents and Other Documents affecting the Properties.

(E) Not less than five (5) business days prior to the Due Diligence

Date, Purchaser shall have the right to provide Seller with a list of Service

Contracts which Purchaser wishes to have assigned to it by Seller, the Joint

Ventures or the Subsidiaries, as applicable, at the Closing (the "Assigned

Contracts"). Purchaser has elected not to assume any management and leasing

commission agreements (subject to Purchaser's obligations under Section

5(C)(i)(c) hereunder) affecting the Property. Seller and the Joint Ventures

shall, or shall cause the Subsidiaries to (i) assign the Assigned Contracts to

Purchaser at Closing to the extent the terms of such contracts permit such

assignment (and Purchaser shall assume the obligations of Seller, the Joint

Ventures and their respective Subsidiaries, as applicable, under the Assigned

Contracts), and (ii) terminate or otherwise assume, and hold Purchaser harmless

from and against, all claims with respect to the Service Contracts which are not

Assigned Contracts as of the Closing. Seller will not enter into or amend,

terminate, waive any default under, or grant concessions regarding any contract

or agreement that will be an obligation affecting the Property or binding on

Purchaser after the Closing (unless the same is terminable on 30 days prior

notice without penalty or premium) without Purchaser's prior written consent,

which shall not be unreasonably withheld conditioned or delayed and which

consent shall be deemed given if Purchaser does not respond within five (5)

business days after request for consent from Seller or a Joint Venture, as

applicable. Any denial of consent shall be accompanied by an explanation as to

why such consent was denied.

(F) Seller and the applicable Joint Venture shall, and shall cause

their respective Subsidiaries to, continue to have the construction and repair

work performed that is set forth on Schedule 3(F)-1 in accordance with the terms

of that certain Lease to Genzyme Corporation (the "Genzyme Lease") for space at

the Property located at 500 Kendall Street, Cambridge, Massachusetts. If the

total amount expended by Seller, such Joint Venture and their respective

Subsidiaries, collectively, for such construction and repair work prior to the

Closing Date is less than $582,884, then the Purchase Price shall be reduced by

an amount equal to the difference between $582,884 and such amount actually

expended. At or prior to Closing, Seller shall provide purchaser with reasonable

back-up documentation substantiating such expenditures. The parties acknowledge

that certain work, that is described on Schedule 3(F)-2, may be performed after

the Closing Date by Seller (or its subsidiaries or affiliates), which work would

result in an increased rent under the Genzyme Lease (such work that increases

such rent to be referred to as the "Genzyme Work"). From time to time, and as

and when Seller (or its applicable subsidiary or affiliate) intends to perform

the Genzyme Work (or any portion thereof), such performing party shall have the

right to give Purchaser a notice (a "Genzyme Work Payment Request") demanding

that Purchaser pay the amounts then required to perform such work (but in no

event more than $1,800,000 in the aggregate), which notice shall be accompanied

by reasonable documentation substantiating the costs contained in such notice.

Purchaser shall pay to such performing party the amount set forth in such

Genzyme Work Payment Request within thirty (30) days after receiving such

notice. Upon completion of the

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applicable Genzyme Work (or applicable portion thereof), Seller shall (or shall

cause its applicable subsidiary or affiliate performing such work to) provide

Purchaser with evidence of such completion that is reasonably required for

Purchaser to enforce its rights under the Genzyme Lease to increase the rent

thereunder based upon such work performed; provided that (i) nothing contained

herein shall obligate Seller or any subsidiary or affiliate to perform the

Genzyme Work unless and to the extent that Purchaser has been given a Genzyme

Work Payment Request and Purchaser has paid the amounts due thereunder when

required hereunder to Seller (or Seller's applicable subsidiary or affiliate

performing such work) and (ii) neither Seller nor any Subsidiary have any

liability hereunder if Purchaser is unable to obtain such increased rent. The

provisions of this Section 3(F) shall survive the Closing.

(G) Seller and the Joint Ventures shall, and shall cause their

respective Subsidiaries to continue in full force and effect existing insurance

coverages for the Properties as disclosed to Purchaser on Schedule 7(A)(iv) or

replacement insurance with coverage that is not materially less favorable.

(H) Estoppel Certificates.

(i) Seller and the Joint Ventures shall use good faith,

commercially reasonable efforts to obtain estoppel letters from all tenants

under Leases demising 50,000 square feet or more, in substantially the form

annexed hereto as Exhibit B or in the form called for under the applicable Lease

if the applicable tenant refuses to execute one substantially in the form

annexed hereto as Exhibit B after being requested to do so by Seller or the

applicable Joint Venture (the "Tenant Estoppels"). If, with respect to a

particular Lease, Seller or the applicable Joint Venture has failed to obtain a

Tenant Estoppel required hereunder, Seller or such Joint Venture may elect to

satisfy the requirement to obtain such estoppel by delivering a seller estoppel

certificate in the form attached hereto as Exhibit C (each, a "Seller Tenant

Estoppel Certificate") as a substitute for any remaining Tenant Estoppels that

have not been obtained; provided, however, that Seller or the applicable Joint

Venture may not provide Seller Tenant Estoppel Certificates with respect to (I)

the Genzyme Lease and (II) any Leases to Vertex Pharmaceuticals Incorporated

("Vertex") to satisfy the Tenant Estoppel condition to Closing hereunder with

respect to such two tenants. Any Seller Tenant Estoppel Certificate shall

survive for the Representation Survival Period and Seller's or the applicable

Joint Venture's liability with respect all Seller Tenant Estoppel Certificates

shall be capped at the Damage Cap (together with any other amounts credited

against such cap); provided, however, that at any time prior to the expiration

of the Representation Survival Period if Seller or a Joint Venture shall receive

and deliver a Tenant Estoppel from any tenant covered in any such Seller Tenant

Estoppel Certificate, then such Seller Tenant Estoppel Certificate shall be

returned to Seller or the applicable Joint Venture and shall be deemed null and

void and of no further force or effect.

(ii) Seller agrees to request, or cause the Subsidiaries to

request, that each of the lenders under the Assumed Loans execute an estoppel

certificate addressed to Purchaser stating (i) that the applicable Assumed Loan

Documents have not been amended, (ii) the outstanding principal balance of the

applicable Assumed Loan and the amounts of all reserve and impound accounts and

(iii) that there are no material defaults under the applicable Assumed Loan (the

"Lender Estoppels"). Seller agrees to use good faith commercially reasonable

efforts to obtain each of the Lender Estoppels. If, with respect to a particular

Assumed Loan, Seller has

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failed to obtain a Lender Estoppel, Seller may elect to satisfy the requirement

to obtain such estoppel by delivering a seller lender estoppel certificate

making the same statements as would have been in the Lender's Estoppel (each, a

"Seller Lender Estoppel Certificate") as a substitute for any remaining Lender

Estoppels that have not been obtained. Any Seller Lender Estoppel Certificate

shall survive the Closing indefinitely and not be subject to the Damage Cap;

provided, however, that at any time if Seller shall receive and deliver a Lender

Estoppel from the lender covered in any such Seller Lender Estoppel

Certificates, then such Seller Lender Estoppel Certificate shall be returned to

Seller and shall be deemed null and void and of no further force or effect.

(iii) Seller agrees to request, or cause the Joint Ventures

and the Subsidiaries to request, that each counterparty ("CER Counterparty") to

that certain Declaration of Covenants, Easements and Restrictions, dated July

17, 2002 (the "CER") and recorded against the Properties which are part of the

development known as "Kendall Square" execute an estoppel certificate (the "CER

Estoppels") addressed to Purchaser in the form required by the CER which shows

no material defaults by KS Parcel A, LLC and KS Parcel D, LLC under the CER. If,

with respect to a particular CER Counterparty, Seller has failed to obtain a CER

Estoppel, Seller may elect to satisfy the requirement to obtain such estoppel by

delivering a seller CER estoppel certificate making the same statements as would

have been in the CER Estoppel (each, a "Seller CER Estoppel Certificate") as a

substitute for any remaining CER Estoppels that have not been obtained. Any

Seller CER Estoppel Certificate shall survive the Closing indefinitely and not

be subject to the Damage Cap; provided, however, that at any time if Seller

shall receive and deliver a CER Estoppel from the CER Counterparty covered in

any such Seller CER Estoppel Certificates, then such Seller CER Estoppel

Certificate shall be returned to Seller and shall be deemed null and void and of

no further force or effect.

(I) Seller shall use commercially reasonable efforts to maintain in

existence all current licenses, permits and approvals, if any, in its name

necessary or reasonably appropriate to the ownership, operation or improvement

of the Properties.

(J) So long as this Agreement is in effect and Purchaser is not in

default hereunder, Seller shall: (i) remove each of the Properties from the

market, and (ii) not actively solicit or negotiate with any other prospective

purchasers of any Property.

4. STATUS OF TITLE OF PROPERTY

(A) State of Title.

At Closing, Purchaser shall accept title to the Premises, subject only

to the following enumerated exceptions (collectively referred to as the

"Permitted Exceptions"):

(i) those agreements, covenants, conditions, restrictions,

encroachments and other matters that are shown on any Title Commitment or

Survey, except to the extent that Seller or the applicable Joint Venture or

Subsidiary is obligated to remove the same pursuant to the express terms of

Sections 4(B) or 4(C) ("Seller Removal Obligations");

(ii) those agreements, covenants, conditions, restrictions and

other matters which are not shown on any Title Commitment or Survey that do not

affect (x) the

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Seller's, a Joint Venture's or any of their respective Subsidiaries' title to

such Premises or (y) the use of such Premises for commercial purposes, in either

case other than to a de minimis extent, but shall not include the Seller Removal

Obligations. The matters set forth on Schedule 4(A)(ii) shall be deemed to be

Permitted Exceptions hereunder;

(iii) the lien of general real estate taxes, personal property

taxes and all water, sewer, utility, trash and other similar charges and

assessments which are not yet due and payable;

(iv) the Leases, Assigned Contracts and Other Documents that

exist as of the Closing (including the Leases and Assigned Contracts that exist

as of the date hereof (other than those that expired or were duly terminated)

and such Leases and Assigned Contracts that are entered into, modified or

renewed after the date hereof not in violation of this Agreement);

(v) all notes or notices of violation of law or municipal

ordinances, orders or requirements that have been noted in or issued by any

federal, state or municipal department having jurisdiction over the Properties

prior to the date hereof;

(vi) any liens, encumbrances or other defects or exceptions to

title insurance coverage caused by Purchaser, by any of Purchaser's

Representatives or by Seller, any Joint Venture, any of their respective

Subsidiaries or any of their respective representatives at Purchaser's or any

Purchaser's Representative's prior request;

(vii) any leases by which Seller, the Joint Ventures or their

respective Subsidiaries hold the right to possess and use any of the Personal

Property;

(viii) the notes, mortgages, indentures and other documents

relating to the financings listed on Schedule 7(A)(xi) attached hereto (such

financings, the "Assumed Loans"; such notes, mortgages, indentures and other

documents related to the Assumed Loans, the "Assumed Loan Documents");

(ix) any state of facts which an accurate survey or personal

inspection of the Property might reveal, provided same do not render title

unmarketable, other than the Seller Removal Obligations;

(x) all rights or easements, if any, of the applicable

jurisdiction or municipality or any public or private utility company, to

maintain telephone wires, pipes, conduits or other facilities which enter or

cross the Properties.

(xi) any lien, encumbrance or governmental obligation which

either affects solely the property of a tenant under a Lease or is the

obligation of such a tenant to discharge, cure or comply with; and

(xii) all laws, regulations, ordinances and deed restrictions

including, without limitation, all environmental, building and zoning

restrictions affecting the Properties or the ownership, use or operation thereof

adopted by any governmental authority having jurisdiction over the Properties or

the ownership, use or operation thereof, and all amendments or

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additions thereto now in effect or which may be in force and effect on the

Closing Date with respect to such Properties.

(B) Preliminary Evidence of Title.

(i) Purchaser acknowledges that it has received the

commitments (each, a "Title Commitment" and collectively, the "Title

Commitments") listed on Schedule 4(B)(i), issued by Stewart Title Guaranty

Company (the "Title Insurer").

(ii) Purchaser acknowledges that it has received copies of all

documents referred to in the Title Commitments and all other documents

evidencing or relating to matters reflected in the Title Commitments.

(iii) Purchaser acknowledges that it has received the as-built

survey (the "Survey") for each of the Premises as listed on Schedule 4(B)(iii).

(iv) Purchaser shall have until the Due Diligence Date to

review the Title Commitments and the Surveys. If, prior to the Due Diligence

Date, Purchaser objects to any matter or condition shown on any Title Commitment

or Survey or otherwise discovers any exceptions to title other than Permitted

Exceptions with respect to any Property, Purchaser shall notify Seller and the

Joint Ventures promptly upon making such determination and, in any event, not

later than 5:00 p.m. (New York City time) on the Due Diligence Date. The

Purchaser's notice (the "Purchaser's Title Objection Notice") shall include an

explanation of such matter, condition or exception. Seller or such Joint

Venture, as applicable shall have until 5:00 p.m. (New York City time) on the

date that is five (5) business days after the delivery of Purchaser's Title

Objection Notice to respond in writing (the "Seller's Title Objection Response")

either that (x) it will cure or correct such matter, condition or exception

prior to Closing, or (y) it is unable or unwilling to cure or correct such

matter, condition or exception (and failure to respond will deemed to be an

election of option (y)). If Seller or such Joint Venture delivers (or is deemed

to have delivered) a Seller's Title Objection Response indicating that it will

not cure or correct such matter, condition or exception, Purchaser shall have

until 5:00 p.m. (New York City time) on the date that is three (3) business days

from the date on which the Seller's Title Objection Response was delivered, or

is deemed to have been delivered, to (i) waive the original Purchaser's Title

Objection Notice, in which event such matter, condition or exception shall be

deemed a Permitted Exception; or (ii) terminate this Agreement by written notice

to Seller and the Joint Ventures. If Seller or such Joint Venture delivers a

Seller's Title Objection Response indicating it will cure or correct such

matter, condition or exception, then Seller or such Joint Venture shall, or

shall cause their respective subsidiaries to, cure or correct such matter,

condition or exception to the reasonable satisfaction of Purchaser on or prior

to the Closing Date. If Purchaser terminates this Agreement pursuant to this

Section, this Agreement shall become null and void and no party shall have any

further rights or obligations under this Agreement, except for the return of the

Earnest Money to Purchaser and the provisions that are expressly stated to

survive the termination of this Agreement. If Purchaser does not elect to

terminate this Agreement (including by not delivering Purchaser's Title

Objection Notice within the required time period) in accordance with this

Section 4(B)(iv), Purchaser shall be deemed to have accepted all matters shown

on the Title Commitments and the Surveys and all other exceptions to title with

respect to

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the Properties which were discovered by Purchaser prior to the Due Diligence

Date, without any change to the other terms of this Agreement.

(C) Title Report and Survey.

Purchaser may elect to obtain a new preliminary title report

or new Title Commitment for each of the Properties, provided that such new

report or Title Commitment shall be obtained from the Title Insurer and not from

any other title insurance company. Purchaser agrees to purchase its title

insurance at Closing from the Title Insurer. Purchaser may also elect to obtain

new Surveys or revise, modify, or re-certify existing Surveys as necessary in

order for the Title Insurer to delete the survey exception from the Title Policy

or otherwise satisfy Purchaser's objectives.

(D) Title Defects.

After the Due Diligence Date, if any revision or update of any

Title Commitment or Survey, including the new preliminary title reports, Title

Commitments and Surveys obtained pursuant to Section 4(C) above, discloses

exceptions to title other than Permitted Exceptions, Purchaser shall so notify

Seller on or before the fifth (5th) business day after receipt of same, or at

Closing, if less than five (5) business days remain from receipt of same and

Closing (the "Objection Cut Off Date"), time being of the essence, and Seller,

or a Joint Venture, as applicable, shall have until Closing (and may adjourn the

Closing for such reasonable periods, not to exceed sixty (60) days in the

aggregate) to have each such exception that is not a Permitted Exception to

title removed or corrected in each case to the reasonable satisfaction of

Purchaser, but subject to Section 4(E). Nothing herein shall require Seller or

the Joint Ventures or any of their Subsidiaries to (i) bring any action or

proceeding to remove any exception that is not a Permitted Exception or (ii)

take any steps, or otherwise incur any expense, in excess of $100,000 for any

one Property and $400,000 in the aggregate for all Properties (such cap amounts

collectively, the "Title and Violations Cure Cap") to remove any exception that

is not a Permitted Exception (except that Seller or a Joint Venture, as

applicable, shall be obligated to remove any and all liens voluntarily placed by

Seller or such Joint Venture or their respective Subsidiaries against any

Property after the date of the applicable Title Commitment in violation of this

Agreement and shall remove any other exceptions that are not Permitted

Exceptions that: (I) are for liquidated amounts, (II) can be removed by the mere

payment of money, and (III) would cost not more than the Title and Violations

Cure Cap to remove). Any exception to title which Purchaser does not raise on or

before the Objection Cut Off Date shall be deemed a Permitted Exception. If

Seller or a Joint Venture, as applicable, fails to have each such exception that

is not a Permitted Exception removed or corrected at or prior to Closing (as

adjourned), Purchaser may at its sole and exclusive option at Closing (as

adjourned), either (a) terminate this Agreement by written notice to Seller and

the Joint Ventures, whereupon all rights and obligations hereunder of each party

shall cease and terminate and be of no further force or effect except those

rights and obligations hereunder that expressly survive the termination of this

Agreement, or (b) elect to accept title to the Property as it then is without

any reduction in, abatement of, or credit against the Purchase Price and such

exceptions shall be deemed Permitted Exceptions; if Purchaser fails to make

either such election at Closing, Purchaser shall be deemed to have elected

option (b).

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(E) Discharge of Title Objections.

Notwithstanding anything herein to the contrary, Seller or a Joint

Venture, as applicable, shall be deemed to have removed or corrected each

matter, condition or exception that is not a Permitted Exception if, in Seller's

or such Joint Venture's discretion and at its sole cost and expense, Seller or

such Joint Venture either (a) causes the Title Insurer to remove such matter,

condition or exception that is not a Permitted Exception as an exception to

title in the title policy issued at Closing or affirmatively insure against the

same in a manner reasonably acceptable to Purchaser, in each case without any

additional cost to Purchaser, whether such insurance is made available in

consideration of payment, bonding, indemnity of Seller or otherwise, or (b)

delivers (i) its own funds (or directs that a portion of the Purchase Price be

delivered) in an amount needed to fully discharge any such matter, condition or

exception to the Title Insurer with instructions for the Title Insurer to apply

such funds to fully discharge any such matter, condition or exception, and (ii)

if required by the Title Insurer, such instruments, in recordable form, as are

necessary to enable the Title Insurer to discharge such matter, condition or

exception of record.

(F) Notices of Violations.

If Seller, the Joint Ventures or their Subsidiaries receive any notes

or notices of material violation (a "Material Violation") of law or municipal

ordinances, orders or requirements that have been noted in or issued by any

federal, state or municipal department having jurisdiction over the Properties

during the period between the date hereof and the Closing Date (exclusive of any

notice or further notice related to matters set forth on Schedule 7(A)(ii))

(each such note or notice, a "Material Violation Notice"), Seller or the

applicable Joint Venture shall so notify Purchaser on or before the fifth (5th)

business day after receipt of same, or at Closing, if less than five (5)

business days remain from receipt of same and Closing, time being of the

essence, and Seller or the applicable Joint Venture shall have until Closing

(and may adjourn the Closing for such reasonable periods, not to exceed sixty

(60) days in the aggregate) to cure or correct each such Material Violation, in

each case as required by the applicable Material Violation Notice. Nothing

herein shall require Seller or the Joint Ventures or any of their Subsidiaries

to (i) bring any action or proceeding to cure or correct any Material Violation,

or (ii) take any steps, or otherwise incur any expense, in excess of the Title

and Violations Cure Cap to cure or correct any Material Violation (except that

Seller or a Joint Venture, as applicable, shall be obligated to cure or correct

any and all Material Violations voluntarily committed by Seller or such Joint

Venture or their respective Subsidiaries with respect to any Property after the

date hereof in violation of this Agreement and shall cure or correct any other

Material Violations that: (I) are for liquidated amounts, (II) can be removed by

the mere payment of money, and (III) would cost not more than the Title and

Violations Cure Cap to cure or correct). If Seller or a Joint Venture, as

applicable, fails to have each such Material Violation cured or corrected at or

prior to Closing (as adjourned), Purchaser may at its sole and exclusive option

at Closing (as adjourned), either (a) terminate this Agreement by written notice

to Seller and the Joint Ventures, whereupon all rights and obligations hereunder

of each party shall cease and terminate and be of no further force or effect

except those rights and obligations hereunder that expressly survive the

termination of this Agreement, or (b) elect to proceed with the Closing without

any reduction in, abatement of, or credit against the Purchase Price and any

obligations of Seller, the Joint Ventures or their subsidiaries to correct or

cure such Material Violations shall be deemed waived

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by Purchaser; if Purchaser fails to make either such election at Closing,

Purchaser shall be deemed to have elected option (b). For the avoidance of

doubt, the Title and Violations Cure Cap shall apply to the aggregate amount, if

any, required to be expended by Seller, the Joint Ventures and their

Subsidiaries hereunder both to (i) remove or correct exceptions to title

discovered after the Due Diligence Date that are not Permitted Exceptions, and

(ii) to correct or cure Material Violations.

5. CLOSING

(A) Closing Date.

Subject to Section 13(B), the "Closing" of the transaction

contemplated by this Agreement (that is, the payment of the Purchase Price, the

transfer of title to the Properties, and the satisfaction of all other terms and

conditions of this Agreement) shall occur at 9:00 a.m. on the date that is

thirty (30) days after the Due Diligence Date (or, if such date is not a

business day, then the next succeeding business day), or as adjourned in

accordance with the express provisions of this Agreement (the "Closing Date") at

the offices of Seller's counsel in New York, New York, or at such other time and

place as Seller, the Joint Ventures and Purchaser shall agree in writing. Five

(5) business days prior to Closing the parties hereto will begin pre-closing the

transaction.

PURCHASER RECOGNIZES THAT IT IS A MATERIAL CONDITION TO THE

OBLIGATIONS OF SELLER AND THE JOINT VENTURES UNDER THIS AGREEMENT THAT THE

CLOSING OCCUR NOT LATER THAN THE CLOSING DATE. ACCORDINGLY, PURCHASER AGREES

THAT, EXCEPT AS EXPRESSLY SET FORTH HEREIN, PURCHASER SHALL NOT BE ENTITLED TO

ANY ADJOURNMENT OF THE CLOSING, TIME BEING OF THE ESSENCE AS TO THE PERFORMANCE

OF THE OBLIGATIONS OF PURCHASER HEREUNDER ON OR PRIOR TO SUCH DATE.

(B) Closing Deliveries.

(i) Seller. At the Closing, Seller and the Joint Ventures

shall deliver or cause to be delivered with respect to each Property or all of

the Properties, as applicable:

(a) to Purchaser, (i), for each Property located in

Massachusetts, a quitclaim deed substantially in the form attached hereto as

Exhibit D-1, and (ii) for each Property located in New Hampshire, (x) a warranty

deed substantially in the form attached hereto as Exhibit D-2, and (y) to the

Title Insurer or the appropriate authority, a real estate excise or transfer tax

affidavit (or other required forms), as required by law and any environmental

disclosure forms, as required by law;

(b) to Purchaser, an omnibus bill of sale and

assignment and assumption of Leases, security deposits, Assigned Contracts,

Personal Property, Other Documents and other property being conveyed pursuant to

this Agreement in the form attached hereto as Exhibit E;

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(c) to Purchaser, a letter advising tenants under the

Leases of the change in ownership of the Premises and where security deposits

will be held, and directing them to pay rent to Purchaser or as Purchaser may

direct (the form of same shall be prepared by Purchaser subject to Seller's

reasonable approval);

(d) to Purchaser, to the extent that the following

are in the possession or control of Seller, a Joint Venture or their respective

Subsidiaries or its property managers, all of the original (or copies if only a

copy is available) Leases, Other Documents, Assumed Loan Documents and Assigned

Contracts, and any and all building plans, surveys, site plans, engineering

plans and studies, utility plans, landscaping plans, development plans,

specifications, drawings, marketing artwork, construction drawings, complete

warranty book including all contractors and subcontractors and other

documentation concerning all or any part of the Property (provided, however,

Seller and the Joint Ventures may keep copies of any of the foregoing); provided

however, at Purchaser's request, Seller and the Joint Ventures will provide any

of such information in electronic format, if same is in the possession or

control of Seller, a Joint Venture or their respective Subsidiaries unless same

is in a proprietary format of a computer program, other computer software or

under a licensing agreement that Seller and the Joint Ventures are not

transferring;

(e) to Purchaser, any transferable bonds, warranties

or guaranties that relate to the Property and in Seller's, a Joint Venture's or

any of their respective Subsidiaries' possession and control;

(f) to Purchaser, a corporate resolution authorizing

the sale and the execution of closing documents, and a certificate of authority

of individuals authorized to consummate the sale on behalf of Seller, the Joint

Ventures and their respective Subsidiaries, or such other reasonable evidence of

Seller's, the Joint Ventures' and their respective Subsidiaries' power and

authority;

(g) to Purchaser, an affidavit from each of the

Subsidiaries that is the owner of a Property, in the form attached hereto as

Exhibit F stating, under penalty of perjury, such entity's U.S. taxpayer

identification number and that such entity is not a foreign person within the

meaning of Section 1445 of the Internal Revenue Code;

(h) to Purchaser, all other documents reasonably

required by Purchaser in order to perfect the conveyance, transfer and

assignment of the Properties to Purchaser as contemplated by this Agreement,

including without limitation, any assignments of tax certiorari claims or Net

Proceeds that are required pursuant to this Agreement; and

(i) to the extent a Property is transferred subject

to an Assumed Loan and/or Other Documents, but subject to the terms of Article

8, to Purchaser and the holder of such Assumed Loan and/or the third parties to

the Other Documents, as applicable, such assignments related to the Assumed

Loan, the Assumed Loan Documents and the Other Documents as shall be required to

transfer to Purchaser all of the right, title, interest and obligations of

Seller, the Joint Ventures and their respective Subsidiaries, as applicable,

with respect to the Assumed Loan, the Assumed Loan Documents and the Other

Documents, which

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shall include any documents required to effectuate the assignment, assumption,

release and other matters set forth on Schedule 8(F).

(j) an assignment of all of the amounts in the

reserve and/or impound accounts held by any lender in connection with any of the

Assumed Loans in form and substance reasonably acceptable to Purchaser and

Seller shall receive a credit at Closing for such amounts pursuant to Section

5(C)(i)(h).

(k) such conveyancing or transfer tax forms or

returns, if any, as are required to be delivered or signed by Seller by

applicable state and local law in connection with the conveyance of the

Property.

(l) an assignment of all of the letters of credit

held by Seller in connection with any of the Leases, including, without

limitation, in connection with the Vertex, Genzyme, Metabolix or Dartmouth

College Leases, if any.

(m) any additional documents that Escrow Agent or the

Title Company may reasonably and customarily require for the proper consummation

of the transaction contemplated by this Agreement.

(ii) Purchaser. At Closing, Purchaser shall deliver or cause

to be delivered, with respect to each Property or all of the Properties, as

applicable:

(a) to Seller (or such parties as may be directed by

Seller), the Cash Balance as required pursuant to Section 2(D) above;

(b) to Seller and the Joint Ventures, executed

counterparts of any other documents listed in Section 5(B)(i) required to be

signed by Purchaser;

(c) to Seller, its applicable Subsidiaries and the

holders of the Assumed Loans and the third parties under the Other Documents,

any Assumption Documents and Instruments or other documents that Purchaser or

its affiliates are required to execute and deliver pursuant to Article 8

hereunder;

(d) to Seller and its applicable Subsidiaries any

Assumed Loan Indemnities that Purchaser is required to execute and deliver

pursuant to Article 8 hereunder; and

(e) to Seller and the Joint Ventures, all other

documents reasonably required by Seller and the Joint Ventures in order to

perfect the conveyance, transfer and assignment of the Properties to Purchaser,

as contemplated by this Agreement, including without limitation any transfer tax

documents and IRS Form 1099.

(iii) Seller and the Joint Ventures shall, at no cost or

expense to them (other than costs that are expressly the obligations of Seller

or the Joint Ventures hereunder) reasonably cooperate with Purchaser in

obtaining the items listed in Section 5(B)(ii)(c)-(e).

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(C) Closing Prorations and Adjustments.

(i) A statement of prorations and other adjustments shall be

prepared by Seller and Purchaser together in conformity with the provisions of

this Agreement not less than ten (10) business days prior to the Closing Date.

For purposes of prorations, Seller, the Joint Ventures and their respective

Subsidiaries, as applicable, shall be deemed the owner of the Properties on the

Closing Date. In addition to prorations and other adjustments that may otherwise

be provided for in this Agreement, including, without limitation, pursuant to

Section 3, the following items are to be prorated or adjusted, as the case may

require, as of 11:59pm on the Closing Date:

(a) Taxes: real estate and personal property taxes

and assessments (initially prorated on the basis of the most recent

ascertainable bill, but subject to re-proration upon issuance of the actual bill

therefor to effect the actual proration). If any tenant in occupancy at the

Closing Date is obligated to pay any Impositions (defined below) directly to the

applicable taxing authority, such Impositions shall not be apportioned.

(b) Rents: Rents and other charges payable by tenants

under the Leases ("Rents") shall be apportioned as and when collected. Any Rents

collected by Purchaser (which shall include Rents collected by any agent acting

for Purchaser) subsequent to the Closing (whether due and payable prior to or

subsequent to the Closing Date) shall be adjusted as of the 11:59 p.m. on the

Closing Date (the "Adjustment Point"), and any portion thereof properly

allocable to periods prior to the Adjustment Point, net of costs of collection

properly allocable thereto, if any, shall be paid by Purchaser to Seller (or

such parties as may be directed by Seller) promptly after the collection thereof

by Purchaser, but subject to the further provisions of this Section in the case

of Rents due prior to the Adjustment Point. If prior to the Closing Seller, the

Joint Ventures and their respective Subsidiaries shall have collected any Rents

(which shall include Rents collected by any agent acting for such parties) which

are properly allocable in whole or in part to periods subsequent to the

Adjustment Point, the portion thereof so allocable to periods subsequent to the

Adjustment Point, net of costs of collection properly allocable thereto, if any,

shall be credited to Purchaser by Seller at the Closing. As used in this Section

the term "costs of collection" shall mean and include reasonable attorneys' fees

and other costs incurred by Purchaser or Seller, the Joint Ventures and their

respective Subsidiaries in collecting any Rents, but shall not include the

regular fees payable to any property manager for the Property, the payroll costs

of any of Seller's, the Joint Ventures' or Purchaser's employees or any other

internal costs or overhead of Seller, the Joint Ventures and their respective

Subsidiaries or Purchaser.

1) Ten (10) business days prior to the Closing,

Seller shall deliver to Purchaser a list of all

tenants which are delinquent in payment of Rents as

of the Adjustment Point, which list shall set forth

the amount of each such delinquency, the period to

which each such delinquency relates and the nature of

the amount due itemizing separately, as applicable,

fixed monthly rent, tax reimbursements, common area

maintenance, operating expense escalations, electric

charges, charges for tenant services, charges for

overtime services, percentage rent and other charges,

if any.

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Any amount collected by Purchaser after the Closing

Date, from tenants who owe Rents for periods prior to

the Closing Date, shall be applied (i) first, in

payment of Rents for the month in which the Closing

Date occurs (the "Closing Month"), (ii) second, in

payment of Rents for the periods preceding the

Closing Month, and (iii) third, in payment of Rents

for the periods following the Closing Month. Each

such amount, less any costs of collection (including

reasonable counsel fees) reasonably allocable

thereto, shall be adjusted and prorated as provided

above, and the party who receives such amount shall

promptly pay over to the other party the portion

thereof to which it is so entitled.

2) Purchaser shall use commercially reasonable

efforts to bill and collect any delinquencies set

forth on the list delivered by Seller pursuant to

this Section for a period of six (6) months after the

Closing and the amount thereof, as, when and to the

extent collected by Purchaser, shall, if due to

Seller or the Joint Ventures pursuant to the

provisions of this Section, be paid by Purchaser to

Seller (or such parties as directed by Seller), less

any costs of collection (including reasonable counsel

fees) reasonably allocable thereto, promptly after

the collection thereof by Purchaser. In no event

shall Purchaser be obligated to institute any actions

or proceedings or to seek the eviction of any tenant

in order to collect any such delinquencies.

Thereafter, Seller and the Joint Ventures shall have

the right to sue tenants to collect such

delinquencies and Purchaser shall cooperate (but

shall not be obligated to spend any money unless

Seller or the Joint Ventures have agreed to reimburse

Purchaser therefor) with Seller and the Joint

Ventures to the extent reasonably necessary,

provided, however, Seller shall have no right to

cause any such tenant to be evicted or to exercise

any other "landlord" remedy (as set forth in the

Lease) against such tenant other than to sue for

collection.

3) Following the Closing and upon the written request

of Seller and the Joint Ventures, as applicable,

Purchaser shall submit or cause to be submitted to

Seller, within thirty (30) days after the end of each

calendar quarter up to and including the calendar

quarter which includes the date that is six (6)

months after the Closing Date, but only so long as

any delinquencies shall be owed to Seller or the

Joint Ventures, a statement which sets forth all

collections made by Purchaser from the tenants which

owe such delinquencies through the end of such

calendar quarter. Seller shall have the right from

time to time following the Closing until ninety (90)

days after receipt by Seller of the last quarterly

statement required hereunder, at Seller's expense, to

examine and audit so much of the books and records of

Purchaser as relate to

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such delinquencies in order to verify the collections

reported by Purchaser in such quarterly statements.

4) Purchaser agrees not to waive or settle any

delinquency owed in whole or in part to Seller or the

Joint Ventures without the prior written consent of

Seller, which consent may be granted or withheld in

Seller's sole discretion.

5) With respect to that portion of Rents which are

payable on an annual, semiannual or other non-monthly

basis, all such payments which become due after the

Closing, to the extent allocable to periods prior to

the Adjustment Point, shall be paid by Purchaser to

Seller (or such parties as may be directed by Seller)

promptly after receipt thereof, subject to costs of

collection, if any, properly allocable thereto. With

respect to that portion of Rents that are

attributable to payments of expenses such as common

area maintenance charges, association charges or

advertising and promotional charges, such Rents shall

be apportioned based on which party paid or will pay

the correlating expenses for the relevant period.

With respect to that portion of Rents which are

billed on an index-based formula or on an estimated

basis during the fiscal or other period for which

paid, at the end of such fiscal or other period

Purchaser shall determine whether the items in

question have been over billed or under billed (or

over- or under-estimated, as applicable). If there

has been an over billing or over-estimation and an

over billed/estimated amount has been received,

Seller shall, promptly after request by Purchaser,

pay to Purchaser the portion of such over

billed/estimated amount which is properly allocable

to the period prior to the Adjustment Point (to the

extent such amount was actually received), and

promptly thereafter Purchaser shall reimburse the

entire over billed/estimated amount to the tenants

which paid the same. If there has been an under

billing or under-estimation, the additional amount

shall be billed by Purchaser to the tenants and any

amount received by Purchaser, net of costs of

collection, if any, to the extent properly allocable

to periods prior to the Adjustment Point shall

promptly be paid by Purchaser to Seller (or such

parties as may be directed by Seller). In the event

that a tenant requires an audit with respect to an

over-billing or under-billing that relates to the

time period prior to the Adjustment Point, Purchaser

shall promptly notify Seller and Seller may either

(i) conduct such audit at its sole cost and expense,

in which case Seller shall consult with Purchaser in

the conduct of same and Purchaser shall reasonably

cooperate with Seller and provide Seller with

reasonable access to any books and records reasonably

necessary to conduct such audit or (ii) decline to

conduct such audit, in which case Seller shall

reimburse Purchaser for the reasonable costs incurred

by Purchaser to

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conduct such audit relating to the time period prior

to the Adjustment Point.

6) Notwithstanding anything to the contrary set forth

in this Section, Seller (or such parties as may be

directed by Seller) shall be entitled to receive, and

Purchaser shall pay to Seller (or such parties as may

be directed by Seller) promptly after receipt

thereof, net of costs of collection and reasonable

attorneys' fees, if any, properly allocable thereto,

(i) all amounts payable by tenants on account of all

real estate and personal property taxes, general and

special assessments, water and sewer charges, license

fees and other fees and charges assessed or imposed

by governmental authorities upon the Properties (the

"Impositions") which, pursuant to the terms of this

Section, it is Seller's obligation to pay and

discharge (to the extent Seller either paid such

amounts or Purchaser received a credit therefor

pursuant to this Section), which amounts shall be

apportioned between Seller and Purchaser in the same

manner as the Impositions to which they relate and

(ii) all amounts payable by tenants on account of

utilities which, pursuant to the terms of this

Section, it is Seller's obligation to pay and

discharge (to the extent Seller either paid such

amounts or Purchaser received a credit therefor

pursuant to this Section), which amounts shall be

apportioned between Seller or such Joint Venture and

Purchaser in the same manner as the utilities to

which they relate. Notwithstanding anything to the

contrary set forth in this Section, Purchaser shall

be entitled to receive, and Seller shall pay to

Purchaser promptly after receipt thereof, net of

costs of collection and reasonable attorneys' fees,

if any, properly allocable thereto, (i) all amounts

payable by tenants on account of Impositions which,

pursuant to the terms of this Section, it is

Purchaser's obligation to pay and discharge (to the

extent Purchaser either paid such amounts or Seller

received a credit therefor pursuant to this Section),

which amounts shall be apportioned between Seller and

Purchaser in the same manner as the Impositions to

which they relate and (ii) all amounts payable by

tenants on account of utilities which, pursuant to

the terms of this Section, it is Purchaser's

obligation to pay and discharge (to the extent

Purchaser either paid such amounts or Seller (or a

party designated by Seller) received a credit

therefor pursuant to this Section), which amounts

shall be apportioned between Seller and Purchaser in

the same manner as the utilities to which they

relate.

7) Any advance rental deposits or payments held by

Seller, a Joint Venture or their respective

Subsidiaries on the Closing Date and applicable to

periods of time subsequent to the Adjustment Point,

and any security deposits held by such parties on the

Closing Date, together with interest thereon, if any,

which, under the terms

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of the applicable Leases, is payable to the tenants

thereunder, shall be paid or credited to Purchaser at

the Closing.

(c) Leasing Costs:

1) Seller and the Joint Ventures shall pay and

indemnify Purchaser in respect of all unpaid leasing

commissions in respect of the initial terms of all

Leases and Lease amendments which were fully executed

and delivered on or prior to the Due Diligence Date

and renewals or extensions thereof executed on or

prior to the Due Diligence Date; provided, however,

that Purchaser, rather than Seller and the Joint

Ventures, shall be responsible for all other leasing

commissions, costs of tenant alterations and

improvements performed or to be performed for tenants

under Leases at the expense of the landlord thereof,

moving and other allowances and inducements, if any,

and fees and disbursements of architects, engineers

and attorneys (collectively "Leasing Costs"),

including all Leasing Costs on behalf of Seller and

the Joint Ventures in respect of any Lease renewal or

extension which occurs pursuant to the exercise after

the Due Diligence Date of any tenant's renewal or

extension option under any Lease which was fully

executed and delivered on or prior to the Due

Diligence Date. At the Closing, Seller shall deliver

an itemized statement, in form and substance

reasonably satisfactory to Purchaser, certifying (i)

all Leasing Costs paid by Seller and the Joint

Ventures pursuant to this Section after the date

hereof and on or prior to the Closing Date, (ii) the

remaining unpaid Leasing Costs for which Seller and

the Joint Ventures are responsible under this Section

and (iii) attaching documentation reasonably

sufficient to demonstrate the payment of such Leasing

Costs. The aggregate unpaid amount of Leasing Costs

so certified shall be deducted from and reduce the

Purchase Price at Closing, and Seller and the Joint

Ventures shall have no further liability under this

Section following the Closing other than for any

inaccuracy in the aforesaid itemized statement or

documentation and Purchaser shall assume the

obligation to pay such unpaid Leasing Costs.

Notwithstanding the provisions of this Section

5(C)(i)(c), (I) Seller, as opposed to Purchaser,

shall be obligated to pay the Leasing Costs

associated with the lease amendments listed on

Schedule 3(C) and Purchaser shall receive a credit at

Closing for any such amounts that have not been paid

by Seller at or prior to Closing and (II) Seller

shall receive a credit at Closing, not to exceed

Seventy-Five Thousand Dollars ($75,000), for any

amounts actually expended by Seller, the Joint

Ventures or their Subsidiaries in connection with the

installation of a reception desk in the lobby of the

Premises located at 675 West Kendall Street,

Cambridge, MA, and Seller shall provide Purchaser

with

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reasonable substantiating backup documentation

regarding the same at Closing.

2) If the Closing shall occur, Purchaser shall and

hereby does assume and agree to pay and indemnify

Seller and the Joint Ventures in respect of (i) all

Leasing Costs payable by Purchaser pursuant to this

Section and (ii) all Leasing Costs payable in respect

of any Leases or Lease amendments which are fully

executed and delivered after the date hereof. If any

Leasing Costs shall be paid by Seller or the Joint

Ventures prior to the Closing, which, in accordance

with this Section, it is Purchaser's obligation to

pay, Purchaser shall reimburse Seller (or such

parties as may be directed by Seller) for the

documented amount thereof at the Closing. Purchaser's

obligation to pay any Leasing Costs that Purchaser is

obligated to pay hereunder shall survive the Closing

indefinitely.

(d) Utilities and fuel charges, including, without

limitation, water, telephone, sewer, steam, electricity, gas, oil charges and

fuel on hand and any assignable deposits with utility companies, on the basis of

current bills and readings obtained by Seller or the Joint Ventures within

thirty (30) days prior to the Adjustment Point (or, if none, on the basis of the

most recent previous bills and readings); provided that, upon the taking of

subsequent actual readings that are as of a date closer in time to the Closing

Date than the date of the readings used to determine the adjustment made at the

Closing pursuant to this sentence, such adjustment shall be recalculated based

upon the subsequent readings, and any necessary compensating adjustments shall

be made to the Purchase Price. No apportionment shall be made in respect of any

utility or fuel, the charges for which are payable by any tenant directly to the

provider of such utility pursuant to the terms of its Lease, unless the tenant

is not current in its payment obligations under its Lease on the Closing Date.

(e) amounts due and prepayments under the Assigned

Contracts and equipment leases.

(f) amounts due, prepayments and the costs of

performing the obligations of Seller or a Joint Venture, as applicable, under

the Assigned Contracts and the Other Documents. Seller shall receive a credit

towards the Purchase Price for any funds deposited with or in escrow with

respect to the Assigned Contracts or Other Documents that are assigned to

Purchaser at Closing, in each case that are not returned to Seller, the Joint

Ventures or their respective Subsidiaries.

(g) assignable license and permit fees.

(h) if a Property is sold subject to an Assumed Loan,

all interest payments related to same and any fees or expenses that have accrued

and remain unpaid or have been paid as of the Closing Date under the Assumed

Loan Documents. In addition, Seller and the Joint Ventures, as applicable, shall

receive a credit towards the Purchase Price for any escrowed funds or funds in

any reserve or impound accounts with respect to the Assumed

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Loans that are assigned to Purchaser at Closing and that are not returned to

Seller, the Joint Ventures or their respective Subsidiaries.

(i) other expenses of operation and similar items,

including without limitation, advertising and marketing expenses.

(j) any other operating expenses and any other items

relating to a Property which, in accordance with customary business practice,

customarily would be apportioned between sellers and buyers of real estate.

(k) any common area maintenance charges with respect

to the Properties located at 675 West Kendall Street, Cambridge, MA and 500

Kendall Street, Cambridge, MA, which are payable under the CER.

(l) except as otherwise specifically provided in this

Agreement or in any other written agreement that may be entered into between

Seller and Purchaser, Seller has paid or will pay in full, prior to Closing (but

subject to apportionment hereunder), all bills and invoices for labor, goods,

material and services of any kind relating to the Properties and utility charges

(except if and to the extent such utility charges are billed directly to

tenants), that are due and payable on or prior to the Closing, and Purchaser

will pay in full, after the Closing (but subject to apportionment hereunder),

all bills and invoices for labor, goods, material and services of any kind

relating to the Properties and utility charges (except if and to the extent such

utility charges are billed directly to tenants), that are due and payable after

Closing.

(ii) Certiorari: Purchaser acknowledges that proceedings for

certiorari or other proceedings to determine the assessed value of the Premises

or the real property taxes payable with respect to each Property as indicated on

Schedule 5(C)(ii) have been commenced prior to the date hereof and may be

continuing as of the Closing Date. Seller and the Joint Ventures, as applicable,

shall be entitled to control the prosecution of any such proceeding or

proceedings for the years prior to but not including the year in which the

Closing occurs to completion and to settle or compromise any Claim therein.

Purchaser, subject to the reasonable consent and approval of Seller and the

Joint Ventures, as applicable, shall be entitled to control the prosecution of

any such proceeding or proceedings for the year in which the Closing occurs to

completion and to settle or compromise any Claim therein, subject to the

reasonable consent of Seller. Purchaser shall keep Seller informed on a timely

basis of all matters with respect to any such proceeding and seek Seller's

consent and approval as required hereunder. The parties hereto agree to

cooperate with each other and to execute any and all documents reasonably

requested by the other parties in furtherance of the foregoing. Seller and the

Joint Ventures, as applicable, shall be entitled to any awards for the years

prior to the year in which the Closing occurs. With respect to any awards for

the year in which the Closing occurs, Seller, the Joint Ventures and their

respective Subsidiaries shall be entitled to first recover the reasonable costs

they have expended in obtaining such awards and Purchaser shall then be entitled

to recover the reasonable cost it has expended in obtaining any such awards and

then, Seller, the Joint Ventures and Purchaser shall apportion the remainder of

such awards between the period prior to Closing and the period subsequent to

Closing. In connection with the foregoing, Seller, the Joint Ventures and their

respective Subsidiaries agree to assign, subject to the provisions of this

Section, to Purchaser at the Closing all of their respective right, title and

interest to the foregoing

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certiorari proceedings that are for the year in which the Closing occurs and all

refunds relating thereto. Each party shall promptly remit to the other monies

received which are to be paid and/or shared as provided herein. No party will

settle or compromise any proceeding that involves an impact to a tax year in

which another party has the right to control, without the consent of such other

party. Notwithstanding the other terms of this Section 5(C)(ii), Seller, the

Joint Ventures and Purchaser each covenants to comply with any terms of any

Lease regarding the obligation of the lessor thereunder to refund any sums

recovered in connection with or as a result of any tax certiorari proceedings

with respect to the Properties. Nothing contained in this paragraph shall be

interpreted to diminish any tenant's right to control an applicable certiorari

proceeding to the extent such tenant has such right under any Lease and has

exercised the same. The provisions of this Section 5(C)(ii) shall survive

Closing until all proceedings with respect to the tax year of the Closing and

prior years are resolved.

(iii) Except with respect to general real estate and personal

property taxes (which shall be re-prorated upon the issuance of the actual

bills, if necessary), any other proration which must be estimated at Closing

shall be re-prorated and finally adjusted as soon as practicable after the

Closing Date but no later than one (1) year from the Closing Date; otherwise all

prorations shall be final.

(iv) The provisions of this Section 5(C) shall survive Closing

for one (1) year, except if a longer time is stated herein.

(D) Closing Costs.

Seller and the Joint Ventures shall be responsible for (i)

their own legal counsel expenses, (ii) all costs incurred to repay any liens and

other expenses due from or incurred by Seller or the Joint Ventures, if

applicable, in connection with the transaction (including prepayment fees or

expenses, if any, regarding any existing liens or mortgages on the Properties,

other than Permitted Exceptions and the Assumed Loans), (iii) one-half of the

escrow fee, if any, which may be charged by the Escrow Agent; (iv) any and all

real estate excise or transfer taxes that are incurred in connection with the

transfer of the Properties and (v) any reasonable and customary attorneys fees

and loan processing fees required by the holders of the Assumed Loans in

connection with the assumption of the Assumed Loans in connection with this

transaction and any fees to Seller's mortgage broker Peter Goedecke ("Goedecke")

in connection with this transaction. Notwithstanding anything to the contrary

contained in this Section, Sell