**  Exhibit10.11.3**

**THIRDAMENDMENT OF LEASES**

THIS THIRDAMENDMENT OF LEASES (the “Third Amendment”) is made this 4th day of January, 2007, by and between **RB KENDALL FEE, LLC** (“Landlord”) and **GENZYME CORPORATION**, having a mailingaddress at 500 Kendall Street, Cambridge, Massachusetts 02139 (“Tenant”).

RECITALS:

Reference is madeto the following:

A.            One Kendall Realty Trust,predecessor-in-interest to Landlord, and Tenant entered into those certainleases (collectively, the “Leases”) described in the Amendment of Leases, datedDecember 17, 2004, between Landlord’s predecessor-in-interest and Tenant (the “FirstAmendment”) and the Second Amendment of Leases, dated July 25, 2005 (the “SecondAmendment”), by and between Landlord’s predecessor in title and Tenant  (collectively, the “Amendments”).  One of the Leases (the “Building 600 Lease”)relates to premises located in Building 600/650/700  (“Building 600”), One Kendall Square,Cambridge, Massachusetts (the “Complex”) and the other Lease relates to premiseslocated in Building 1400 (the “Building 1400 Lease”) in the Complex.  Capitalized terms used but not defined hereinshall have the same meaning as in the Lease or Amendments.

B.            Landlord and Tenant are the currentholders, respectively, of the lessor’s and lessee’s interests in the Lease.

C.            The term of the Leases with respectto Premises A and Premises B (all as defined in the Second Amendment), asextended in accordance with the terms of the First Amendment by notices fromTenant to Landlord dated May 31, 2006 and September 22, 2006, is set to expireon June 24, 2007.

D.            Landlord and Tenant want to extendthe term of the Leases with respect to certain portions of the demisedpremises, confirm the annual Base Rent payable during such extended term andfurther revise the Leases as set forth in this Third Amendment.

E.             Landlord and Tenant now desire toamend the Leases as set forth herein.

AGREEMENTS:

NOW, THEREFORE, inconsideration of the mutual covenants and agreements herein contained, and forother good and valuable consideration, the receipt and sufficiency of which arehereby acknowledged, Landlord and Tenant hereby agree to amend the Leases asfollows:

1.             Premises B.  The term of the Building 1400 Lease withrespect to Premises B, which contains 37,435 square feet, is hereby extendedfor an additional term commencing June 25, 2007 and expiring on February 28,2008 (the “Premises B Extended Term”). From the date hereof until the expiration of the Premises B ExtendedTerm, the annual Base Rent in respect of Premises B shall be $935,875.00,payable in monthly amounts of $77,989.58 in accordance with the terms of theBuilding 1400 Lease.

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2.             Revised Definition of Premises A.  The parties agrees that, for all purposesunder this Third Amendment, the demised premises comprising Premises A (asdefined in the Amendments) shall be redefined as follows:

                “Premises A 2007” shall consistof a portion of the premises currently demised under the Building 600 Lease andthe Building 1400 Lease, as amended by the Amendments, containing, in theaggregate, 84,280 rentable square feet, as shown on Exhibit A, Sheets 1, 2 and3, attached hereto, as follows:

a)                                         Aportion of the lower level of Building 600 containing 4,914 square feet ofspace;

b)                                        Aportion of the fourth (4th) andfifth (5th) floors(including a portion of the fourth (4th)floor mezzanine) of Building 600 containing 62,810 square feet of space; and 

c)                                         Aportion of the fifth (5th)floor of Building 1400 containing 16,556 square feet of space.

 

“PremisesA 2008” shall consist of a portion of the premises currently demised under theBuilding 600 Lease, as amended by the Amendments, containing, in the aggregate,36,036 rentable square feet in Building 600, as shown on Exhibit B, Sheets 1, 2and 3 attached hereto as follows:

a)                                         Aportion of the fourth (4th)floor containing 25,324 square feet of space;

b)                                        Aportion of the fourth (4th)floor containing 4,441 square feet of space;

c)                                         Aportion of the fourth (4th)floor mezzanine containing 1,841 square feet of space;

d)                                        Aportion of the fifth (5th)floor containing 4,329 square feet of space;

e)                                         Aportion of the fifth (5th)floor containing 101 square feet of space; and

f)                                           TheSecurity & IT Closets as shown on Sheet 3 of Exhibit B.

 

3.             Premises A 2007.  The term of the Leases with respect toPremises A 2007 is hereby extended for an additional term commencing June 25,2007 and expiring on September 30, 2007.   During the period commencing on the date hereof and expiring on March24, 2007, the annual Base Rent in respect of Premises A 2007 shall be$2,528,400.00, payable in monthly amounts of $210,700.00.  During the period commencing March 25, 2007and expiring September 30, 2007, the annual Base Rent in respect of Premises2007 A shall be $2,633,750.00, payable in monthly amounts of $219,479.16.

4.             Premises A 2008.  The term of the Building 600 Lease withrespect to Premises A 2008 is hereby extended for an additional term commencingJune 25, 2007 and expiring on February 28, 2008.  During the period commencing on the datehereof and expiring on March 24, 2007, the annual Base Rent in respect ofPremises A 2008 shall be $1,081,080.00, payable in monthly amounts of$90,090.00.  During the period commencingMarch 25, 2007 and expiring February 28, 2008, the annual Base Rent in respectof Premises A 2008 shall be $1,126,125.00, payable in monthly amounts of$93,843.75.

5.             No Further Extension Rights orRights of First Refusal.  Tenantacknowledges and agrees that it shall have no further right to extend the termof the Leases beyond the dates set forth in this Third Amendment and no rightsof first refusal on any space within the Complex.  Without limiting the foregoing, Sections 2.2,3.2 and 3.3 of the First Amendment shall be void and without further force oreffect.

6.             Tenant’s Proportionate Shares.  Throughout the term of the Leases, asextended herein, Tenant shall continue to pay Lessee’s Proportionate CAO LotShare, Lessee’s Proportionate Building Share and Tenant’s pro rata share ofreal estate taxes, with the calculation of said payment being adjusted 

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to reflect any decreasein rentable square footage leased by Tenant as Tenant surrenders space inaccordance with the provisions of this Third Amendment.  After the Tenant surrenders Premises A 2007to Landlord in accordance with the terms of the Building 600 Lease, Building1400 Lease, Amendments and this Third Amendment, the Lessee’s Proportionate CAOLot Share under the Building 600 Lease shall be 5.54%, Lessee’s ProportionateBuilding Share under the Building 600 Lease shall be 16.03%, Lessee’sProportionate CAO Lot Share under the Building 1400 Lease shall be 5.75%,Lessee’s Proportionate Building Share under the Building 1400 Lease shall be28.13% and Tenant’s pro rata share of real estate taxes under each of theLeases shall be the same percentages as set forth above.

7.             Utilities.  Tenant’s obligation to pay for utilities, asset forth in the Leases, shall continue throughout the term with any pro ratapayments being adjusted to reflect any decrease in rentable square footageleased by Tenant as Tenant surrenders space in accordance with the provisionsof this Third Amendment.  The partiesacknowledge that Landlord is unaware of the specifics of how electrical serviceis distributed by the utility company to the various premises leased byTenant.  Tenant agrees, however, that ifthe entirety of Premises A 2007 is not separately metered from Premises B andPremises A 2008, then after expiration of the term for Premises A 2007, and nolater than October 31, 2007, Tenant shall, at Tenant’s sole cost and expense,furnish and install any necessary metering equipment to measure the consumptionof electric current in Premises A 2007 separately from Premises B and PremisesA 2008.  If Landlord elects to take backthe Surrendered Space (as defined below), then Tenant shall, at Tenant’s solecost and expense and within thirty (30) days after the Surrender Date (asdefined below) (or such longer period as is reasonably necessary to completethe hereinafter described work, provided that Tenant has commenced and isdiligently pursuing the completion of such work and; further provided, thatsuch period shall not extend beyond ninety (90) days after the Surrender Date)furnish and install any necessary metering equipment to measure the consumptionof electric current in the Surrendered Space separately from the remainingportion of Premises A 2007 occupied by Tenant and separately from Premises Band Premises A 2008.

8.             No Interior Cleaning Service.  Landlord and Tenant acknowledge and agreethat Landlord does not provide, and is not obligated to provide, any interiorcleaning services for the Premises B, Premises A 2007 or Premises A 2008.  Landlord shall not charge Tenant for anyinterior cleaning services and such charges shall not be included in Lessee’sProportionate CAO Lot Share or Lessee’s Proportionate Building.

9.             Take Back Option.  Commencing January 1, 2007, Landlord has theoption, exercisable on thirty (30) days prior written notice to Tenant, to takeback the portion of Premises A 2007 consisting of 16,556 rentable square feeton the fifth (5th)floor of Building 1400 as shown on Exhibit A, Sheet 3 (the “Surrendered Space”).  Landlord’s notice shall set forth the date bywhich Tenant must yield up the Surrendered Space to Landlord in the conditionrequired under the Leases, Amendments and this Third Amendment (the “SurrenderDate”).  In no event shall the SurrenderDate be earlier than thirty (30) days after the date of Landlord’s notice.  If Tenant needs additional time todecommission the Surrendered Space, as required under this ThirdAmendment,  Tenant may extend theSurrender Date on a day-to day basis in order to complete its decommissioningwork provided Tenant has commenced such work prior to the original SurrenderDate and is working diligently to complete such work.  As of the Surrender Date, Lessee’sProportionate CAO Lot Share under the Building 600 Lease shall be 15.95%,Lessee’s Proportionate Building Share under the Building 600 Lease shall be 46.16%,Lessee’s Proportionate CAO Lot Share under the Building 1400 Lease shall be5.75%, Lessee’s Proportionate Building Share under the Building 1400 Leaseshall be 28.13% and Tenant’s pro rata share of real estate taxes under each ofthe Leases shall be the same percentages as set forth above.  As of the Surrender Date, the Leases shallautomatically terminate with respect only to the Surrendered Space as if theLeases had expired by its 

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terms with respect to theSurrendered Space and Tenant shall be automatically relieved from all furtherobligations with respect to the Surrendered Space as of the Surrender Date,except as to those obligations in the Leases that expressly survivetermination.

10.           Parking.  Throughout the term of the Leases, theLandlord will make available to Tenant one monthly parking pass for each 1,000rentable square feet of space currently leased by Tenant pursuant to the Leasesfor use in the One Kendall Square Garage (the “Garage”).  As of the date hereof, Tenant shall have theright to use 158 parking spaces in the Garage based on the square footage forPremises B, Premises A 2007 and Premises A 2008.  Tenant shall have no right to sublet, assign,or otherwise transfer said parking passes except in connection with anassignment of the Leases or sublease of the premises permitted pursuant to theprovisions of the Leases.  Said parkingpasses shall be paid for by Tenant at the then current prevailing rate in theGarage, as such rate may vary from time to time.  The current rate for such passes, as of thedate of this Third Amendment, is $200.00 per month.  If, for any reason, Tenant shall fail timelyto pay the charge for said parking passes, Landlord shall have the same rightsagainst Tenant as Landlord has with respect to the timely payment of Base Renthereunder.  Said parking passes will beon an unassigned, non-reserved basis, and shall be subject to reasonable rulesand regulations from time to time in force. Tenant shall have the right, from time to time, upon at least thirty (30)days prior written notice to Landlord, to surrender one or more of such parkingpasses, and upon such surrender, Tenant shall have no further rights orobligations with respect to such surrendered passes.  As Tenant surrenders portions of the demised premisesin accordance with this Third Amendment, Tenant shall also surrender thecorresponding parking passes.   Duringthe term of the Leases Landlord agrees to notify Tenant when additional parkingspaces become available in the Garage and Tenant shall have the option toutilize such spaces on a month-to-month basis at the then current prevailingrate in the Garage.  The provisions ofthis Paragraph 10 shall replace all others in the Leases relating to parkingspaces in the Garage.

11.           Removal of Signage.  Upon execution of this Third Amendment,Tenant shall commence, at its sole cost and expense,  the removal of any of its signage, if any,from the front entrance, glass awning entrance and the clock tower on Building1400.  At the expiration of the term ofthe Leases, Tenant shall remove, at its sole cost and expense, all of itsexterior signage, if any, from Building 600. The removal of such signage shall not damage the premises or Building1400 or Building 600, as the case may be, and the cost of repairing any damageto the premises or said buildings arising from such removal shall be paid byTenant.

12.           Decommissioning of Premises.  On or before the date of the expiration ofthe term for Premises B, Premises A 2007 or Premises A 2008 or the Surrender Dateif Landlord exercises its termination option in Paragraph 9 of this ThirdAmendment, Tenant shall:

a)             Cause those portions of Premises B,Premises A 2007, Premises A 2008 or the Surrendered Space, as the case may be,used for laboratory purposes to be decommissioned in accordance with theregulations of the U.S. Nuclear Regulatory Commission and/or the MassachusettsDepartment of Public Health for the control of radiation, cause such premisesto be released for unrestricted use by the Radiation Control Program of theMassachusetts Department of Public Health for the control of radiation, anddeliver to Landlord the report of a certified industrial hygienist or acertified health physicist, as the case may be, stating that he or she hasexamined such premises (including visual inspection, Geiger counter evaluationand airborne and surface monitoring) and found no evidence that such portion ofsuch premises contains Hazardous Materials, as defined in this Third Amendment,or is otherwise in violation of any Environmental Law, as also defined in thisThird Amendment hereof.

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b)            Provide to Landlord a copy of itsmost current chemical waste removal manifest and a certification from Tenantexecuted by an officer of Tenant that to the knowledge of such officer, afterdue investigation, no Hazardous Materials or other potentially dangerous orharmful chemicals brought onto such premises from and after the date thatTenant first took occupancy of the premises remain in such premises.

13.           Defined Terms.  As used herein the term “Environmental Law”means collectively all laws, statutes, ordinances, rules and regulations of anylocal, state or federal governmental authority having jurisdiction concerningenvironmental, health and safety matters, including, but not limited to, anydischarge into the air, surface, water, sewers, soil or groundwater of anyHazardous Materials.  As used herein, theterm “Hazardous Materials” means any hazardous or toxic substance, material orwaste or petroleum derivative which is or becomes regulated by anyEnvironmental Law, specifically including live organisms, viruses and fungi,medical waste, and so-called “biohazard” materials.  The term “Hazardous Materials” includes,without limitation, any material or substance which is (i) designated as a “hazardoussubstance” pursuant to Section 1311 of the Federal Water Pollution Control Act(33 U.S.C. Section 1317), (ii) defined as a “hazardous waste” pursuant toSection 1004 of the Federal Resource Conservation and Recovery Act, 42 U.S.C.Section 6901 et seq. (42 U.S.C. Section 6903), (iii) defined as a “hazardoussubstance” pursuant to Section 101 of the Comprehensive Environmental Response,Compensation and Liability Act, 42 U.S.C. Section 9601 et seq. (42 U.S.C.Section 9601), (iv) defined as “hazardous substance” or “oil” under Chapter 21Eof the General Laws of Massachusetts, or (v) a so-called “biohazard” or medicalwaste, or is contaminated with blood or other bodily fluids; and “EnvironmentalLaw” includes, without limitation, the laws listed in the preceding clauses (i)through (iv).

14.           Systems.  Upon the expiration of the term of theLeases, Tenant shall ensure that all mechanical systems remaining in PremisesB, Premises A 2007 and Premises A 2008, including, without limitation, Tenant’semergency medical and fire systems shall be in good, working order, normal wearand tear excepted as of such premises’ respective term expiration dates..

15.           Segregation of Premises.  In the event Landlord leases any portion ofPremises A 2007 after such premises are vacated by Tenant, Tenant and Landlordshall cooperate (a) in separating the vacated premises from the remainingpremises still occupied by Tenant with separate demising walls; (b) in ensuringthat the tenants leasing such premises have all necessary ingress and egress inand out of the premises as may be required by applicable laws and (c) inensuring that the vacant space meets applicable code requirements.  Any work required to be completed in PremisesA 2007, or in the adjacent premises still occupied by Tenant after vacatingPremises A 2007, in order to ensure such compliance and to segregate the vacantspace from the occupied space shall be performed by Landlord, at Landlord’scost, during normal business hours; provided, however, that Landlord shall usereasonable efforts to minimize any disruption to Tenant’s use of itspremises.  Subject to the provisionshereof, Tenant agrees to provide Landlord and its contractors with ready accessto the remaining premises occupied by Tenant, during normal business hours, tocomplete such work; provided, however, that Landlord shall use reasonableefforts to minimize any disruption to Tenant’s use of its premises.  Tenant acknowledges and agrees that theoperation of the plumbing and electric systems and the furnishing of heatingand air conditioning services to the premises still occupied by the Tenant maybe temporarily interrupted as a result of the work contemplated in thisparagraph.  Landlord shall exercisereasonable diligence to minimize any such interruption, and provided thatLandlord exercises such efforts, there shall be no diminution or abatement ofrent or other compensation due from Landlord to Tenant as a result of suchinterruption, nor shall the Leases be affected or any of Tenant’s obligationsunder the Leases be reduced, and Landlord shall have 

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no responsibility orliability for any such interruption of services or systems provided thatLandlord is acting with reasonable diligence as set forth herein.  Landlord, at Landlord’s sole cost andexpense, shall be responsible for any damage to Tenant’s property or thepremises caused in whole or in part by Landlord’s negligent act or omissionrelative to the segregation of the premises as contemplated by this paragraph15.  Notwithstanding any provision to thecontrary contained herein, Tenant shall have the right at all times to have anagent or representative of Tenant accompany Landlord, Landlord’s contractors,licensees, agents, servants, employees, invitees or visitors or anyone enteringany portion of Premises B, Premises A 2007 or Premises A 2008 at Landlord’sdiscretion or on Landlord’s behalf.

16.           Removal of Tenant’s Wiring.  Tenant agrees to reimburse Landlord forone-half of the actual cost reasonably incurred by Landlord for the removal ofall telecommunications lines and cabling installed by Tenant in Premises B,Premises A 2007 or Premises A 2008, including, without limitation, any suchlines and cabling installed in the plenum or risers of Building 600 and/orBuilding 1400 (“Tenant’s Wiring”). Landlord shall deliver a written statement to Tenant, providingreasonable detail of the work performed and the costs incurred byLandlord.  In no event shall Tenant’sreimbursement obligation exceed $100,000 in the aggregate.  Landlord shall not commence the removal ofTenant’s Wiring in a particular portion of the premises until after theexpiration of the term for the respective portion of the premises.  However, in the event Tenant vacates anyportion of Premises B, Premises A 2007 or Premises A 2008 prior to thescheduled expiration date of the term as set forth in this Third Amendment,Landlord shall be permitted to remove Tenant’s Wiring from the vacated spaceimmediately upon Tenant’s surrender of said space to Landlord provided Landlordcan complete such removal without unreasonably interfering with Tenant’sbusiness operations in the remaining space occupied by Tenant.

17.           Notices.  For all purposes of the Leases, the noticeaddress for Landlord shall hereafter be as follows: RB Kendall Fee, LLC, OneKendall Square, Cambridge, Massachusetts 02139. Any notices given to Landlord shall be delivered in accordance with theterms of the Leases to the foregoing address with copies to be delivered inlike manner to Landlord, c/o The Beal Companies, LLP, 177 Milk Street, Boston,Massachusetts, Attention: Stephen N. Faber, Vice President and to Sherin andLodgen, LLP, 101 Federal Street, Boston, Massachusetts 02110, Attention: PeterA. Spellios, Esquire.

For all purposesof the Leases, the notice address for Tenant shall hereafter be asfollows:  Genzyme Corporation, MetroWestSummit, 11 Pleasant Street Connector, Framingham, Massachusetts 01701, Attn:Henry Fitzgerald.  Any notices given toTenant shall be delivered in accordance with the terms of the Leases to theforegoing address with copies to be delivered in like manner to:  Genzyme Corporation, 500 Kendall Street,Cambridge, Massachusetts 02142, Attn: Bob Hesslein, Esq., and to Edwards AngellPalmer & Dodge, 111 Huntington Avenue, Boston, Massachusetts 02199, Attn:Thomas G. Schnorr, Esq.

Notwithstandingany provision in the Leases to the contrary, any notices or othercommunications under the Leases may be delivered in person, by nationallyrecognized commercial delivery service, next business day delivery, certifiedmail with return receipt requested or by registered mail, postage prepaid.

18.           Brokers.  Landlord and Tenant each warrant andrepresent to the other that they have dealt with no brokers in connection withthe negotiation or consummation of this Third Amendment other than LincolnProperty Company and Trammell Crow Company (the “Brokers”) and in the event ofany brokerage claim against either party by any person claiming to have dealtwith either Landlord or Tenant in connection with this Third Amendment, otherthan the Brokers, the party with whom such person claims to have dealt shalldefend and indemnify the other party against such claim.  Landlord shall pay any commission due theBrokers pursuant to a separate agreement.

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19.           In all other respects the Leasesshall remain unmodified and shall continue in full force and effect, as amendedhereby.  The parties hereby ratify,confirm, and reaffirm all of the terms and conditions of the Leases, as amendedhereby.

 

[Signatures appearon next page]

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IN WITNESS WHEREOF the parties hereto have executedthis Third Amendment of Leases on the date first written above in multiplecopies, each to be considered an original hereof, as a sealed instrument.
|            | ** ** | **LANDLORD:**       | ** **                                 | **TENANT:**         |
|------------|------------|---------------------|--------------------------------------------|---------------------|
| ** ** | ** ** | ** **          | ** **                                 | ** **          |
|       |       | RB KENDALL FEE, LLC |                                       | GENZYME CORPORATION |
|       |       |                |                                       |                |
|       |       | By:                 | Beal Kendall LLC, its authorized signatory |                |   |
|       |       |                |                                       |                |   |
|       |       | By:                 | /s/ Robert L. Beal                         |                | By: | /s/ Mark Bamforth |
|       |       |                | Robert L. Beal, its manager                |                | Name: | Mark Bamforth |
|       |       |                |                                       | Title:              | Senior Vice President |

 

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