EX-10.5





			
		  	

  

 Exhibit 10.5 

LEASE AGREEMENT 
 THIS LEASE
AGREEMENT (this “Lease”) is made this 31st day of August, 2016, between ARE-MA REGION NO. 24, LLC, a Delaware limited
liability company (“Landlord”), and HOMOLOGY MEDICINES, INC., a Delaware corporation (“Tenant”).  
  

			
	 Building:
	  	45 Wiggins Avenue, Bedford, MA 01730
		
	 Premises:
	  	That portion of the Building, containing approximately 23,000 rentable square feet, as determined by Landlord, as shown on Exhibit A. 
		
	 Project:
	  	The real property on which the Building in which the Premises are located, together with all improvements thereon and appurtenances thereto as described on Exhibit B. 
		
	 Base Rent:
	  	$36.00 per rentable square foot of the Premises per year

 Rentable Area of Premises: 23,000 sq. ft. 

Rentable Area of Building: 38,000 sq. ft. 
 Rentable
Area of Project: 171, 154 sq. ft. 
 Tenant’s Share of Operating Expenses of Building: 60.53% 

Building’s Share of Operating Expenses of Project: 13.44% 

Security Deposit: $276,000 
 Rent Adjustment Percentage:
3% 
  

			
	 Base Term:
	  	Beginning on the Commencement Date and ending 60 months and 14 days from the first day of the first full month after the Rent Commencement Date (as defined in Section 2) hereof.
		
	 Permitted Use:
	  	Research and development laboratory, related office, storage, and other related uses consistent with the character of the Project and otherwise in compliance with the provisions of Section 7 hereof.

  

			
	Address for Rent Payment:	  	Landlord’s Notice Address:
	P.O. Box 37526	  	385 E. Colorado Boulevard, Suite 299
	Baltimore, MD 21297-3526	  	Pasadena, CA 91101
		  	Attention: Corporate Secretary
		
	Tenant’s Notice Address	  	Tenant’s Notice Address
	Prior to the Commencement Date:	  	As of the Commencement Date:
	44 Hartwell Avenue, Suite 102	  	45 Wiggins Avenue
	Lexington, MA 02421	  	Bedford, MA 01730
	Attention: Sam Rasty	  	Attention: Sam Rasty


  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 The following Exhibits and Addenda are attached hereto and incorporated herein by this reference: 

 

							
	 [X]
	  	EXHIBIT A - PREMISES DESCRIPTION	  	[X]	  	EXHIBIT B- DESCRIPTION OF PROJECT
	 [X]
	  	EXHIBIT C - WORK LETTER	  	[X]	  	EXHIBIT D - COMMENCEMENT DATE
	 [X]
	  	EXHIBIT E - RULES AND REGULATIONS	  	[X]	  	EXHIBIT F - TENANT’S PERSONAL PROPERTY
	 [X]
	  	EXHIBIT G - INTENTIONALLY OMITTED	  	[X]	  	EXHIBIT H - LANDLORD’S FURNITURE

 1. Lease of Premises. Upon and subject to all of the terms and conditions hereof, Landlord hereby
leases the Premises to Tenant and Tenant hereby leases the Premises from Landlord. The portions of the Project which are for the non-exclusive use of tenants of the Project are collectively referred to herein
as the “Common Areas.” Landlord reserves the right to modify Common Areas, provided that such modifications do not materially adversely affect Tenant’s use of the Premises for the Permitted Use. Landlord shall endeavor to
provide Tenant with at least 30 days’ advance written notice of such modifications. 
 Tenant acknowledges and agrees that Landlord
may, in Landlord’s sole and absolute discretion, make significant changes to the exterior landscape, parking areas and ingress/egress routes for the Project (“Site Work”), which Site Work may include, at Landlord’s cost
and expense, the removal of the stone from the exterior portion of the Building described on Exhibit A attached hereto and the replacement of the stone with glazing (collectively, the “Building Work”). Tenant acknowledges
that Landlord may require access to a portion of the Premises following the Commencement Date in order to perform the Building Work. Landlord and its contractors shall have the right to enter the Premises following the Commencement Date to perform
the Building Work. Landlord shall use reasonable efforts to coordinate the Building Work with Tenant in order to minimize interference with Tenant’s operations at the Premises in connection with the Building Work. Tenant acknowledges that
Landlord’s performance of the Site Work and Building Work may adversely affect tenant’s use of the Common Areas of the Project and Landlord’s performance of the Building Work may adversely affect Tenant’s use and occupancy of the
Premises. Tenant waives all claims against Landlord in connection with the Site Work and the Building Work including, without limitation, claims for rent abatement. Nothing herein shall obligate Landlord to perform the Site Work or the Building
Work. 
 2. Delivery; Acceptance of Premises; Commencement Date. Landlord shall deliver the Premises to Tenant on or before the date
that is 2 business days after the mutual execution and delivery of this Lease by the parties, vacant (free of other tenants and occupants), free of all personal property and in broom clean condition for the construction of the Tenant Improvements by
Tenant (“Delivery” or “Deliver”). As used herein, the term “Tenant Improvements” shall have the meaning set forth for such term in the Work Letter. 

The “Commencement Date” shall be the date Landlord Delivers the Premises to Tenant. The “Rent Commencement Date”
shall be the earlier of (i) date that is 3 months and 14 days after the Commencement Date, or (ii) the date that Tenant commences doing business in any portion of the Premises. Upon request of Landlord, Tenant shall execute and deliver
a written acknowledgment of the Commencement Date, the Rent Commencement Date and the expiration date of the Term when such are established in the form of the “Acknowledgement of Commencement Date” attached to this Lease as Exhibit D;
provided, however, Tenant’s failure to execute and deliver such acknowledgment shall not affect Landlord’s rights hereunder. The “Term” of this Lease shall be the Base Term, as defined above on the first
page of this Lease and the Extension Term which Tenant may elect pursuant to Section 40 hereof. 
 Except as otherwise expressly
set forth in this Lease or in the Work Letter: (i) Tenant shall accept the Premises in their condition as of the Commencement Date, subject to all applicable Legal Requirements (as defined in Section 7 hereof); (ii) Landlord shall
have no obligation for any defects in the Premises; and (iii) Tenant’s taking possession of the Premises shall be conclusive evidence that Tenant accepts the Premises and that the Premises were in good condition at the time possession was
taken. Any occupancy of the Premises by Tenant before the Commencement Date shall be subject to all of the terms and conditions of this Lease, excluding the obligation to pay Base Rent and Operating Expenses. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 Notwithstanding anything to the contrary contained herein, for the period of 30 consecutive
days after the Commencement Date, Landlord shall, at its sole cost and expense (which shall not constitute an Operating Expense), be responsible for any repairs that are required to be made to the Building or Building Systems (as defined in
Section 13), unless Tenant or any Tenant Party was responsible for the cause of such repair, in which case Tenant shall pay the cost. 

During the Term, Tenant shall lease from Landlord, for $1.00 per year, the removable furniture located within the Premises as of the date of
this Lease and listed on Exhibit H attached hereto (“Landlord’s Furniture”). Tenant shall have no right to remove any of Landlord’s Furniture from the Premises without Landlord’s prior written consent and
Landlord’s Furniture shall be returned to Landlord at the expiration or earlier termination of the Term in substantially the same condition as received by Tenant, except for ordinary wear and tear. Notwithstanding the foregoing, if Tenant
elects to exercise its Extension Right pursuant to Section 40, then the ownership of Landlord’s Furniture shall be deemed transferred to Tenant and the same shall become Tenant’s property as of the first day of the Extension
Term. 
 Tenant agrees and acknowledges that neither Landlord nor any agent of Landlord has made any representation or warranty with respect
to the condition of all or any portion of the Premises or the Project, and/or the suitability of the Premises or the Project for the conduct of Tenant’s business, and Tenant waives any implied warranty that the Premises or the Project are
suitable for the Permitted Use. This Lease constitutes the complete agreement of Landlord and Tenant with respect to the subject matter hereof and supersedes any and all prior representations, inducements, promises, agreements, understandings and
negotiations which are not contained herein. Landlord in executing this Lease does so in reliance upon Tenant’s representations, warranties, acknowledgments and agreements contained herein. 

 

	 	3.	Rent. 

 (a) Base Rent. Base Rent for the month in which the Rent
Commencement Date occurs and the Security Deposit shall be due and payable on delivery of an executed copy of this Lease to Landlord. Tenant shall pay to Landlord in advance, without demand, abatement, deduction or
set-off, equal monthly installments of Base Rent on or before the first day of each calendar month during the Term hereof, in lawful money of the United States of America, at the office of Landlord for payment
of Rent set forth above, or to such other person or at such other place as Landlord may from time to time designate in writing. Payments of Base Rent for any fractional calendar month shall be prorated. The obligation of Tenant to pay Base Rent and
other sums to Landlord and the obligations of Landlord under this Lease are independent obligations. Tenant shall have no right at any time to abate, reduce, or set-off any Rent (as defined in
Section 5) due hereunder except for any abatement as may be expressly provided in this Lease. 
 Notwithstanding anything to the
contrary contained herein, for the period commencing on the Rent Commencement Date through last day of the 6th month following the Rent Commencement Date, Tenant shall only be required to pay Base
Rent in the amount of $18.00 per rentable square foot of the Premises per year. Tenant shall commence paying Base Rent in the amount set forth on page 1 of this Lease on the first day of the 7th
month after the Rent Commencement Date. 
 (b) Additional Rent. In addition to Base Rent, Tenant agrees to pay to Landlord as
additional rent (“Additional Rent”): (i) commencing on the Rent Commencement Date, Tenant’s Share of “Operating Expenses” (as defined in Section 5), and (ii) any and all other
amounts Tenant assumes or agrees to pay under the provisions of this Lease, including, without limitation, any and all other sums that may become due by reason of any default of Tenant or failure to comply with the agreements, terms, covenants and
conditions of this Lease to be performed by Tenant, after any applicable notice and cure period. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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	 	4.	Base Rent Adjustments.  

 (a) Annual Adjustments. Base Rent shall be
increased on each annual anniversary of the first day of the first full month following the Rent Commencement Date (each an “Adjustment Date”) by multiplying the Base Rent payable immediately before such Adjustment Date by
the Rent Adjustment Percentage and adding the resulting amount to the Base Rent payable immediately before such Adjustment Date. Base Rent, as so adjusted, shall thereafter be due as provided herein. Base Rent adjustments for any fractional calendar
month shall be prorated. 
 (b) Additional Allowance. In addition to the Tenant Improvement Allowance (as defined in the Work
Letter), Landlord shall, subject to the terms of the Work Letter, make available to Tenant the Additional Tenant Improvement Allowance (as defined in the Work Letter). Commencing on the Rent Commencement Date and continuing thereafter on the first
day of each month during the Base Term, Tenant shall pay the amount necessary to fully amortize the portion of the Additional Tenant Improvement Allowance actually funded by Landlord, if any, in equal monthly payments with interest at a rate of 8.5%
per annum over the Base Term, which interest shall begin to accrue on the date that Landlord first disburses such Additional Tenant Improvement Allowance or any portion(s) thereof. Any of the Additional Tenant Improvement Allowance and applicable
interest remaining unpaid as of the expiration or earlier termination of the Lease shall be paid to Landlord in a lump sum at the expiration or earlier termination of this Lease. 

5. Operating Expense Payments. Landlord shall deliver to Tenant a written estimate of Operating Expenses for each calendar year
during the Term (the “Annual Estimate”), which may be revised by Landlord from time to time during such calendar year. During each month of the Term, on the same date that Base Rent is due, Tenant shall pay Landlord an
amount equal to 1/12th of Tenant’s Share of the Annual Estimate. Payments for any fractional calendar month shall be prorated. 
 The
term “Operating Expenses” means all costs and expenses of any kind or description whatsoever incurred or accrued each calendar year by Landlord with respect to the Building (including the Building’s Share of all
costs and expenses of any kind or description incurred or accrued by Landlord with respect to the Project which are not specific to the Building or any other building located in the Project) (including, without duplication, Taxes (as defined in
Section 9), capital repairs and improvements amortized over the lesser of 10 years and the useful life of such capital items, and the costs of Landlord’s third party property manager or, if there is no third party property manager,
administration rent in the amount of 3.0% of Base Rent), excluding only: 
 (a) the original construction costs of the Project and
renovation prior to the date of the Lease and costs of correcting defects in such original construction or renovation; 
 (b) capital
expenditures for expansion of the Project; 
 (c) interest, principal payments of Mortgage (as defined in Section 27) debts of
Landlord, financing costs and amortization of funds borrowed by Landlord, whether secured or unsecured; 
 (d) depreciation of the Project
(except for capital improvements, the cost of which are includable in Operating Expenses); 
 (e) advertising, legal and space planning
expenses and leasing commissions and other costs and expenses incurred in procuring and leasing space to tenants for the Project, including any leasing office maintained in the Project, free rent and construction allowances for tenants; 

(f) legal and other expenses incurred in the negotiation or enforcement of leases; 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 (g) completing, fixturing, improving, renovating, painting, redecorating or other work, which
Landlord pays for or performs for other tenants within their premises, and costs of correcting defects in such work; 
 (h) costs to be
reimbursed by other tenants of the Project or Taxes to be paid directly by Tenant or other tenants of the Project, whether or not actually paid; 

(i) salaries, wages, benefits and other compensation paid to officers and employees of Landlord who are not assigned in whole or in part to
the operation, management, maintenance or repair of the Project; 
 (j) general organizational, administrative and overhead costs relating
to maintaining Landlord’s existence, either as a corporation, partnership, or other entity, including general corporate, legal and accounting expenses; 

(k) costs (including attorneys’ fees and costs of settlement, judgments and payments in lieu thereof) incurred in connection with
disputes with tenants, other occupants, or prospective tenants, and costs and expenses, including legal fees, incurred in connection with negotiations or disputes with employees, consultants, management agents, leasing agents, purchasers or
mortgagees of the Building; 
 (l) costs incurred by Landlord due to the violation by Landlord, its employees, agents or contractors or any
tenant of the terms and conditions of any lease of space in the Project or any Legal Requirement (as defined in Section 7); 

(m) penalties, fines or interest incurred as a result of Landlord’s inability or failure to make payment of Taxes and/or to file any tax
or informational returns when due, or from Landlord’s failure to make any payment of Taxes required to be made by Landlord hereunder before delinquency; 

(n) overhead and profit increment paid to Landlord or to subsidiaries or affiliates of Landlord for goods and/or services in or to the Project
to the extent the same exceeds the costs of such goods and/or services rendered by unaffiliated third parties on a competitive basis; 
 (o)
costs of Landlord’s charitable or political contributions, or of fine art maintained at the Project; 
 (p) costs in connection with
services (including electricity), items or other benefits of a type which are not standard for the Project and which are not available to Tenant without specific charges therefor, but which are provided to another tenant or occupant of the Project,
whether or not such other tenant or occupant is specifically charged therefor by Landlord; 
 (q) costs incurred in the sale or refinancing
of the Project; 
 (r) net income taxes of Landlord or the owner of any interest in the Project, franchise, capital stock, gift, estate or
inheritance taxes or any federal, state or local documentary taxes imposed against the Project or any portion thereof or interest therein; and 

(s) any expenses otherwise includable within Operating Expenses to the extent actually reimbursed by persons other than tenants of the Project
under leases for space in the Project. 
 Within 90 days after the end of each calendar year (or such longer period as may be reasonably
required), Landlord shall furnish to Tenant a statement (an “Annual Statement”) showing in reasonable detail: (a) the total and Tenant’s Share of actual Operating Expenses for the previous calendar year, and
(b) the total of Tenant’s payments in respect of Operating Expenses for such year. If Tenant’s Share of actual Operating Expenses for such year exceeds Tenant’s payments of Operating Expenses for such year, the excess shall be
due and payable by Tenant as Rent within 30 days after delivery of such Annual 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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Statement to Tenant. If Tenant’s payments of Operating Expenses for such year exceed Tenant’s Share of actual Operating Expenses for such year Landlord shall pay the excess to Tenant
within 30 days after delivery of such Annual Statement, except that after the expiration, or earlier termination of the Term or if Tenant is delinquent in its obligation to pay Rent, Landlord shall pay the excess to Tenant after deducting all other
amounts due Landlord. Landlord’s and Tenant’s obligations to pay any overpayments or deficiencies due pursuant to this paragraph shall survive the expiration or earlier termination of this Lease. 

The Annual Statement shall be final and binding upon Tenant unless Tenant, within 90 days after Tenant’s receipt thereof, shall contest
any item therein by giving written notice to Landlord, specifying each item contested and the reason therefor. If, during such 90 day period, Tenant reasonably and in good faith questions or contests the accuracy of Landlord’s statement of
Tenant’s Share of Operating Expenses, Landlord will provide Tenant with access to Landlord’s books and records in connection with the operation of the Project and such information in connection with the operation of the Project as Landlord
reasonably determines to be responsive to Tenant’s questions (the “Expense Information”). If after Tenant’s review of such Expense Information, Landlord and Tenant cannot agree upon the amount of
Tenant’s Share of Operating Expenses, then Tenant shall have the right to have an independent regionally recognized public accounting firm selected by Tenant and approved by Landlord (which approval shall not be unreasonably withheld or
delayed), working pursuant to a fee arrangement other than a contingent fee (at Tenant’s sole cost and expense), audit and/or review the Expense Information for the year in question (the “Independent Review”). The
results of any such Independent Review shall be binding on Landlord and Tenant. If the Independent Review shows that Tenant’s actual payments with respect to the Operating Expenses for the calendar year in question exceeded Tenant’s Share
of Operating Expenses for such calendar year, Landlord shall at Landlord’s option either (i) credit the excess amount to the next succeeding installments of estimated Operating Expenses or (ii) pay the excess to Tenant within 30 days
after delivery of such statement, except that after the expiration, or earlier termination of this Lease or if Tenant is delinquent in its obligation to pay Rent, Landlord shall pay the excess to Tenant after deducting all other amounts due
Landlord. If the Independent Review shows that Tenant’s payments with respect to Operating Expenses for such calendar year were less than Tenant’s Share of Operating Expenses for the calendar year, Tenant shall pay the deficiency to
Landlord within 30 days after delivery of such statement. If the Independent Review shows that Tenant has overpaid Tenant’s Share of Operating Expenses by more than 5% then Landlord shall reimburse Tenant for all costs incurred by Tenant for
the Independent Review. Operating Expenses for the calendar years in which Tenant’s obligation to share therein begins and ends shall be prorated. Notwithstanding anything set forth herein to the contrary, if the Building is not at least 95%
occupied on average during any year of the Term, Tenant’s Share of Operating Expenses for such year shall be computed as though the Building had been 95% occupied on average during such year. 

Tenant acknowledges and agrees that the Rentable Area of Premises and Tenant’s Share of Operating Expenses may be adjusted by Landlord by
written notice to Tenant (which written notice shall be binding on Tenant) to include “park common” rentable square footage of approximately 400 square feet attributable to a
“grab-and-go” food area which Landlord may install at the Project, to the extent such
“grab-and-go” food area is actually installed by Landlord. Nothing herein shall obligate Landlord to install any such “grab-and-go” food area at the Project. 
 “Tenant’s
Share” shall be the percentage set forth on the first page of this Lease as Tenant’s Share as reasonably adjusted by Landlord for changes in the physical size of the Premises or the Project occurring thereafter. Landlord may
equitably increase Tenant’s Share for any item of expense or cost reimbursable by Tenant that relates to a repair, replacement, or service that benefits only the Premises or only a portion of the Project that includes the Premises or that
varies with occupancy or use. Base Rent, Tenant’s Share of Operating Expenses and all other amounts payable by Tenant to Landlord hereunder are collectively referred to herein as “Rent.” 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 6. Security Deposit. Tenant shall deposit with Landlord, upon delivery of an
executed copy of this Lease to Landlord, a security deposit (the “Security Deposit”) for the performance of all of Tenant’s obligations hereunder in the amount set forth on page 1 of this Lease, which Security
Deposit shall be in the form of an unconditional and irrevocable letter of credit (the “Letter of Credit”): (i) in form and substance satisfactory to Landlord, (ii) naming Landlord as beneficiary,
(iii) expressly allowing Landlord to draw upon it at any time from time to time by delivering to the issuer notice that Landlord is entitled to draw thereunder, (iv) issued by an FDIC-insured financial institution satisfactory to Landlord,
and (v) redeemable by presentation of a sight draft in the state of Landlord’s choice. If Tenant does not provide Landlord with a substitute Letter of Credit complying with all of the requirements hereof at least 5 days before the stated
expiration date of any then current Letter of Credit, Landlord shall have the right to draw the full amount of the current Letter of Credit and hold the funds drawn in cash without obligation for interest thereon as the Security Deposit. The
Security Deposit shall be held by Landlord as security for the performance of Tenant’s obligations under this Lease. The Security Deposit is not an advance rental deposit or a measure of Landlord’s damages in case of Tenant’s default.
Upon each occurrence of a Default (as defined in Section 20), Landlord may use all or any part of the Security Deposit to pay delinquent payments due under this Lease, future rent damages, and the cost of any damage, injury, expense or
liability caused by such Default, without prejudice to any other remedy provided herein or provided by law. Landlord’s right to use the Security Deposit under this Section 6 includes the right to use the Security Deposit to pay
future rent damages following the termination of this Lease pursuant to Section 21(c) below. Upon any use of all or any portion of the Security Deposit, Tenant shall pay Landlord on demand the amount that will restore the Security
Deposit to the amount set forth on Page 1 of this Lease. Tenant hereby waives the provisions of any law, now or hereafter in force, which provide that Landlord may claim from a security deposit only those sums reasonably necessary to remedy defaults
in the payment of Rent, to repair damage caused by Tenant or to clean the Premises, it being agreed that Landlord may, in addition, claim those sums reasonably necessary to compensate Landlord for any other loss or damage, foreseeable or
unforeseeable, caused by the act or omission of Tenant or any officer, employee, agent or invitee of Tenant. Upon bankruptcy or other debtor-creditor proceedings against Tenant, the Security Deposit shall be deemed to be applied first to the payment
of Rent and other charges due Landlord for periods prior to the filing of such proceedings. If Tenant shall fully perform every provision of this Lease to be performed by Tenant, the Security Deposit, or any balance thereof (i.e., after deducting
therefrom all amounts to which Landlord is entitled under the provisions of this Lease), shall be returned to Tenant (or, at Landlord’s option, to the last assignee of Tenant’s interest hereunder) within 90 days after the expiration or
earlier termination of this Lease. 
 If Landlord transfers its interest in the Project or this Lease, Landlord shall either
(a) transfer any Security Deposit then held by Landlord to a person or entity assuming Landlord’s obligations under this Section 6, or (b) return to Tenant any Security Deposit then held by Landlord and remaining after the
deductions permitted herein. Upon such transfer to such transferee or the return of the Security Deposit to Tenant, Landlord shall have no further obligation with respect to the Security Deposit, and Tenant’s right to the return of the Security
Deposit shall apply solely against Landlord’s transferee. The Security Deposit is not an advance rental deposit or a measure of Landlord’s damages in case of Tenant’s default. Landlord’s obligation respecting the Security Deposit
is that of a debtor, not a trustee, and no interest shall accrue thereon. 
 If, as of the expiration of the 24th month after the Rent Commencement Date, (i) Tenant is not in Default of this Lease, and (ii) Tenant has not been in Default of this Lease at any time during the Term of this Lease
(collectively, the “Reduction Requirements” and each a “Reduction Requirement”), then the Security Deposit shall be reduced to $207,000 (the “Reduced Security
Deposit”). If Tenant provides Landlord with a written request to Landlord for such reduction of the Security Deposit, then, so long as all of the Reduction Requirements have been met, Landlord shall cooperate with Tenant, at no cost,
expense or liability to Landlord, to reduce the Letter of Credit then held by Landlord to the amount of the Reduced Security Deposit. If the Security Deposit is reduced as provided herein, then from and after the date of such reduction, the
“Security Deposit” shall be deemed to be the Reduced Security Deposit, for all purposes of this Lease. 
 7.
Use. The Premises shall be used solely for the Permitted Use set forth in the basic lease provisions on page 1 of this Lease, and in compliance with all laws, orders, judgments, ordinances, regulations, codes, directives, permits,
licenses, covenants and restrictions now or hereafter applicable to the Premises, and to the use and occupancy thereof, including, without limitation, the Americans With 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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Disabilities Act, 42 U.S.C. § 12101, et seq. (together with the regulations promulgated pursuant thereto, “ADA”) (collectively, “Legal
Requirements” and each, a “Legal Requirement”). Tenant shall, upon 5 days’ written notice from Landlord, discontinue any use of the Premises which is declared by any Governmental Authority (as defined in
Section 9) having jurisdiction to be a violation of a Legal Requirement. Tenant will not use or permit the Premises to be used for any purpose or in any manner that would void Tenant’s or Landlord’s insurance, increase the
insurance risk, or cause the disallowance of any sprinkler or other credits. Tenant shall not permit any part of the Premises to be used as a “place of public accommodation”, as defined in the ADA or any similar legal requirement. Tenant
shall reimburse Landlord promptly upon demand for any additional premium charged for any such insurance policy by reason of Tenant’s failure to comply with the provisions of this Section or otherwise caused by Tenant’s use and/or occupancy
of the Premises. Tenant will use the Premises in a careful, safe and proper manner and will not commit or permit waste, overload the floor or structure of the Premises, subject the Premises to use that would damage the Premises or obstruct or
interfere with the rights of Landlord or other tenants or occupants of the Project, including conducting or giving notice of any auction, liquidation, or going out of business sale on the Premises, or using or allowing the Premises to be used for
any unlawful purpose. Tenant shall cause any equipment or machinery to be installed in the Premises so as to reasonably prevent sounds or vibrations from the Premises from extending into Common Areas, or other space in the Project. Tenant shall not
place any machinery or equipment weighing 500 pounds or more in or upon the Premises or transport or move such items through the Common Areas of the Project or in the Project elevators without the prior written consent of Landlord. Tenant shall not,
without the prior written consent of Landlord, use the Premises in any manner which will require ventilation, air exchange, heating, gas, steam, electricity or water beyond the existing capacity of the Project as proportionately allocated to the
Premises based upon Tenant’s Share as usually furnished for the Permitted Use. 
 Landlord shall, at Landlord’s cost and not as
part of Operating Expenses, be responsible for the compliance of the Common Areas of the Project with Legal Requirements as of the Commencement Date. Following the Commencement Date, Landlord shall, as an Operating Expense (to the extent such Legal
Requirement is generally applicable to similar buildings in the area in which the Project is located) and at Tenant’s expense (to the extent such Legal Requirement is triggered by reason of Tenant’s, as compared to other tenants of the
Project, specific use of the Premises, the Tenant Improvements or Tenant’s Alterations) make any alterations or modifications to the Common Areas or the exterior of the Building that are required by Legal Requirements. Except as provided in the
2 immediately preceding sentences, Tenant, at its sole expense, shall make any alterations or modifications to the interior of the Premises that are required by Legal Requirements (including, without limitation, compliance of the Premises with the
ADA) related to Tenant’s specific use or occupancy of the Premises, the Tenant Improvements or Tenant’s Alterations. Notwithstanding any other provision herein to the contrary, Tenant shall be responsible for any and all demands, claims,
liabilities, losses, costs, expenses, actions, causes of action, damages or judgments, and all reasonable expenses incurred in investigating or resisting the same (including, without limitation, reasonable attorneys’ fees, charges and
disbursements and costs of suit) (collectively, “Claims”) arising out of or in connection with Legal Requirements related to Tenant’s specific use or occupancy of the Premises, the Tenant Improvements or
Tenant’s Alterations, and Tenant shall indemnify, defend, hold and save Landlord harmless from and against any and all Claims arising out of or in connection with any failure of the Premises to comply with any Legal Requirement related to
Tenant’s specific use or occupancy of the Premises, the Premises Improvements or Tenant’s Alterations. 
 8. Holding
Over. If, with Landlord’s express written consent, Tenant retains possession of the Premises after the termination of the Term, (i) unless otherwise agreed in such written consent, such possession shall be subject to immediate
termination by Landlord at any time, (ii) all of the other terms and provisions of this Lease (including, without limitation, the adjustment of Base Rent pursuant to Section 4 hereof) shall remain in full force and effect (excluding
any expansion or renewal option or other similar right or option) during such holdover period, (iii) Tenant shall continue to pay Base Rent in the amount payable upon the date of the expiration or earlier termination of this Lease or such other
amount as Landlord may indicate, in Landlord’s sole and absolute discretion, in such written consent, and (iv) all other payments shall continue under the terms of this Lease. If Tenant remains in possession of the Premises after the
expiration or earlier termination of the Term without the express written consent of 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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Landlord, (A) Tenant shall become a tenant at sufferance upon the terms of this Lease except that the monthly rental shall be equal to 150% of Rent in effect during the last 30 days of the
Term, and (B) Tenant shall be responsible for all damages suffered by Landlord resulting from or occasioned by Tenant’s holding over, including consequential damages; provided, however, that if Tenant delivers a written inquiry to Landlord
within 30 days prior to the expiration or earlier termination of the Term, Landlord will notify Tenant whether the potential exists for consequential damages. No holding over by Tenant, whether with or without consent of Landlord, shall operate to
extend this Lease except as otherwise expressly provided, and this Section 8 shall not be construed as consent for Tenant to retain possession of the Premises. Acceptance by Landlord of Rent after the expiration of the Term or earlier
termination of this Lease shall not result in a renewal or reinstatement of this Lease. 
 9. Taxes. Landlord shall pay, as
part of Operating Expenses, Tenant’s Share of all taxes, levies, fees, assessments and governmental charges of any kind, existing as of the Commencement Date or thereafter enacted (collectively referred to as “Taxes”),
imposed by any federal, state, regional, municipal, local or other governmental authority or agency, including, without limitation, quasi-public agencies (collectively, “Governmental Authority”) during the Term,
including, without limitation, all Taxes: (i) imposed on or measured by or based, in whole or in part, on rent payable to (or gross receipts received by) Landlord under this Lease and/or from the rental by Landlord of the Project or any portion
thereof, or (ii) based on the square footage, assessed value or other measure or evaluation of any kind of the Premises or the Project, or (iii) assessed or imposed by or on the operation or maintenance of any portion of the Premises or
the Project, including parking, or (iv) assessed or imposed by, or at the direction of, or resulting from Legal Requirements, or interpretations thereof, promulgated by any Governmental Authority, or (v) imposed as a license or other fee,
charge, tax, or assessment on Landlord’s business or occupation of leasing space in the Project. Landlord may contest by appropriate legal proceedings the amount, validity, or application of any Taxes or liens securing Taxes. Taxes shall not
include any net income taxes imposed on Landlord except to the extent such net income taxes are in substitution for any Taxes payable hereunder. If any such Tax is levied or assessed directly against Tenant, then Tenant shall be responsible for and
shall pay the same at such times and in such manner as the taxing authority shall require. Tenant shall pay, prior to delinquency, any and all Taxes levied or assessed against any personal property or trade fixtures placed by Tenant in the Premises,
whether levied or assessed against Landlord or Tenant. If any Taxes on Tenant’s personal property or trade fixtures are levied against Landlord or Landlord’s property, or if the assessed valuation of the Project is increased by a value
attributable to improvements in or alterations to the Premises, whether owned by Landlord or Tenant and whether or not affixed to the real property so as to become a part thereof, higher than the base valuation on which Landlord from time-to-time allocates Taxes to all tenants in the Project, Landlord shall have the right, but not the obligation, to pay such Taxes. Landlord’s determination of any
excess assessed valuation shall be binding and conclusive, absent manifest error. The amount of any such payment by Landlord shall constitute Additional Rent due from Tenant to Landlord immediately upon demand. 

10. Parking. Subject to all matters of record, Force Majeure, a Taking (as defined in Section 19 below) and the
exercise by Landlord of its rights hereunder, Tenant shall have the right, at no additional cost during the Term (including the Extension Term), in common with other tenants of the Project pro rata in accordance with the rentable area of the
Premises and the rentable areas of the Project occupied by such other tenants, to park in those areas designated for non-reserved parking on a first come first served basis, subject in each case to
Landlord’s rules and regulations. As of the Commencement Date, Tenant’s pro rata share of parking spaces is equal to 2.5 parking spaces per 1,000 rentable square feet of the Premises (or 57 parking spaces). Landlord may allocate parking
spaces among Tenant and other tenants in the Project pro rata as described above if Landlord determines that such parking facilities are becoming crowded. Landlord shall not be responsible for enforcing Tenant’s parking rights against any third
parties, including other tenants of the Project. Landlord shall have the right, exercisable by notice to Tenant given at any time during the Term, to relocate all or a portion of the parking spaces made available to Tenant hereunder to another
location within an approximately 2-minute walk of the Project. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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	 	11.	Utilities, Services.  

 (a) General. Landlord shall provide, subject
to the terms of this Section 11, water, electricity, heat, light, power, sewer, and other utilities (including gas and fire sprinklers to the extent the Project is plumbed for such services), refuse and trash collection and janitorial
services (collectively, “Utilities”). Landlord shall pay, as Operating Expenses or subject to Tenant’s reimbursement obligation, for all Utilities used on the Premises, Tenant’s Share of all maintenance
charges for Utilities, and any storm sewer charges or other similar charges for Utilities imposed by any Governmental Authority or Utility provider, and Tenant’s Share of any taxes, penalties, surcharges or similar charges thereon. Landlord may
cause, at Tenant’s expense, any Utilities to be separately metered or charged directly to Tenant by the provider. Tenant shall pay directly to the Utility provider, prior to delinquency, any separately metered Utilities and services which may
be furnished to Tenant or the Premises during the Term. Tenant shall pay, as part of Operating Expenses, its share of all charges for jointly metered Utilities based upon consumption, as reasonably determined by Landlord. No interruption or failure
of Utilities, from any cause whatsoever other than Landlord’s gross negligence or willful misconduct, shall result in eviction or constructive eviction of Tenant, termination of this Lease or the abatement of Rent. Tenant agrees to limit use of
water and sewer with respect to Common Areas to normal restroom use. Utilities shall be available to the Premises 24 hours per day, 7 days per week, except in the case of emergencies, as the result of Legal Requirements, the failure of any Utility
provider to provide such Utilities, the performance by Landlord or any Utility provider of any installation, maintenance or repairs, or any other temporary interruptions. 

(b) Generator. Landlord’s sole obligation for either providing emergency generators or providing emergency back-up power to Tenant shall be: (i) to provide emergency generators with not less than the capacity of the emergency generators located in the Building as of the Commencement Date, and (ii) to contract
with a third party to maintain the emergency generators as per the manufacturer’s standard maintenance guidelines. Landlord shall have no obligation to provide Tenant with operational emergency generators or
back-up power or to supervise, oversee or confirm that the third party maintaining the emergency generators is maintaining the generators as per the manufacturer’s standard guidelines or otherwise. During
any period of replacement, repair or maintenance of the emergency generators when the emergency generators are not operational, including any delays thereto due to the inability to obtain parts or replacement equipment, Landlord shall have no
obligation to provide Tenant with an alternative back-up generator or generators or alternative sources of back-up power. Tenant expressly acknowledges and agrees that
Landlord does not guaranty that such emergency generators will be operational at all times or that emergency power will be available to the Premises when needed. 

(c) Loading Dock. Tenant may use the loading dock exclusively serving the Premises 24 hours per day, 7 days per week, subject to
downtime to maintenance and repairs. 
 12. Alterations and Tenant’s Property. Any alterations, additions, or improvements made
to the Premises by or on behalf of Tenant, including additional locks or bolts of any kind or nature upon any doors or windows in the Premises, but excluding installation, removal or realignment of furniture systems (other than removal of furniture
systems owned or paid for by Landlord) not involving any modifications to the structure or connections (other than by ordinary plugs or jacks) to Building Systems (as defined in Section 13) (“Alterations”)
shall be subject to Landlord’s prior written consent, which may be given or withheld in Landlord’s sole discretion if any such Alteration affects the structure or Building Systems and shall not be otherwise unreasonably withheld. If
Landlord approves any Alterations, Landlord may impose such conditions on Tenant in connection with the commencement, performance and completion of such Alterations as Landlord may deem appropriate in Landlord’s sole and absolute discretion.
Any request for approval shall be in writing, delivered not less than 15 business days in advance of any proposed construction, and accompanied by plans, specifications, bid proposals, work contracts and such other information concerning the nature
and cost of the alterations as may be reasonably requested by Landlord, including the identities and mailing addresses of all persons performing work or supplying materials. Landlord’s right to review plans and specifications and to monitor
construction shall be solely for its own benefit, and Landlord shall have no duty to ensure that such plans 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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and specifications or construction comply with applicable Legal Requirements. Tenant shall cause, at its sole cost and expense, all Alterations to comply with insurance requirements and with
Legal Requirements and shall implement at its sole cost and expense any alteration or modification required by Legal Requirements as a result of any Alterations. Tenant shall pay to Landlord, as Additional Rent, on demand an amount equal to 2% of
all charges incurred by Tenant or its contractors or agents in connection with any Alteration to cover Landlord’s overhead and expenses for plan review, coordination, scheduling and supervision. Before Tenant begins any Alteration, Landlord may
post on and about the Premises notices of non-responsibility pursuant to applicable law. Tenant shall reimburse Landlord for, and indemnify and hold Landlord harmless from, any expense incurred by Landlord by
reason of faulty work done by Tenant or its contractors, delays caused by such work, or inadequate cleanup. 
 Tenant shall furnish security
or make other arrangements satisfactory to Landlord to assure payment for the completion of all Alterations work free and clear of liens, and shall provide (and cause each contractor or subcontractor to provide) certificates of insurance for
workers’ compensation and other coverage in amounts and from an insurance company satisfactory to Landlord protecting Landlord against liability for personal injury or property damage during construction. Upon completion of any Alterations,
Tenant shall deliver to Landlord: (i) sworn statements setting forth the names of all contractors and subcontractors who did the work and final lien waivers from all such contractors and subcontractors; and (ii) “as built” plans for
any such Alteration. 
 Except for Removable Installations (as hereinafter defined), all Installations (as hereinafter defined) shall be and
shall remain the property of Landlord during the Term and following the expiration or earlier termination of the Term, shall not be removed by Tenant at any time during the Term, and shall remain upon and be surrendered with the Premises as a part
thereof. Notwithstanding the foregoing, Landlord may, at the time its approval of any such Installation is requested, notify Tenant that Landlord requires that Tenant remove such Installation upon the expiration or earlier termination of the Term,
in which event Tenant shall remove such Installation in accordance with the immediately succeeding sentence. Upon the expiration or earlier termination of the Term, Tenant shall remove (i) all wires, cables or similar equipment which Tenant has
installed in the Premises or in the risers or plenums of the Building, (ii) any Installations for which Landlord has given Tenant notice of removal in accordance with the immediately preceding sentence, and (iii) all of Tenant’s
Property (as hereinafter defined), and Tenant shall restore and repair any damage caused by or occasioned as a result of such removal, including, without limitation, capping off all such connections behind the walls of the Premises and repairing any
holes. During any restoration period beyond the expiration or earlier termination of the Term, Tenant shall pay Rent to Landlord as provided herein as if said space were otherwise occupied by Tenant. If Landlord is requested by Tenant or any lender,
lessor or other person or entity claiming an interest in any of Tenant’s Property to waive any lien Landlord may have against any of Tenant’s Property, and Landlord consents to such waiver, then Landlord shall be entitled to be paid as
administrative rent a fee of $1,000 per occurrence for its time and effort in preparing and negotiating such a waiver of lien. 
 For
purposes of this Lease, (x) “Removable Installations” means any items listed on Exhibit F attached hereto and any items agreed by Landlord in writing to be included on Exhibit F in the future, (y)
“Tenant’s Property” means Removable Installations and, other than Installations, any personal property or equipment of Tenant that may be removed without material damage to the Premises, and (z) “Installations”
means all property of any kind paid for out of the Tl Fund, all Alterations, all fixtures, and all partitions, hardware, built-in machinery, built-in casework and
cabinets and other similar additions, equipment, property and improvements built into the Premises so as to become an integral part of the Premises, including, without limitation, fume hoods which penetrate the roof or plenum area, built-in cold rooms, built-in warm rooms, walk-in cold rooms, walk-in warm rooms, deionized
water systems, glass washing equipment, autoclaves, chillers, built-in plumbing, electrical and mechanical equipment and systems, and any power generator and transfer switch. 

13. Landlord’s Repairs. Landlord, as an Operating Expense, shall maintain all of the structural, exterior, parking and other
Common Areas of the Project, including HVAC, plumbing, fire sprinklers, elevators and all other building systems serving the Premises and other portions of the Project (including, without limitation, the RODI water system and the compressed air
system) (“Building  

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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Systems”), in good repair, reasonable wear and tear and uninsured losses and damages caused by Tenant, or by any of Tenant’s agents, servants, employees, invitees and contractors
(collectively, “Tenant Parties”) excluded. Losses and damages caused by Tenant or any Tenant Party shall be repaired by Landlord, to the extent not covered by insurance, at Tenant’s sole cost and expense. Landlord reserves the
right to stop Building Systems services when necessary (i) by reason of accident or emergency, or (ii) for planned repairs, alterations or improvements, which are, in the judgment of Landlord, desirable or necessary to be made, until said
repairs, alterations or improvements shall have been completed. Landlord shall have no responsibility or liability for failure to supply Building Systems services during any such period of interruption; provided, however, that Landlord
shall, except in case of emergency, make a commercially reasonable effort to give Tenant 48 hours advance notice of any planned stoppage of Building Systems services for routine maintenance, repairs, alterations or improvements. Landlord shall use
reasonable efforts to minimize interference with Tenant’s operations in the Premises during such planned stoppages of Building Systems. Tenant shall promptly give Landlord written notice of any repair required by Landlord pursuant to this
Section, after which Landlord shall make a commercially reasonable effort to effect such repair. Landlord shall not be liable for any failure to make any repairs or to perform any maintenance unless such failure shall persist for an unreasonable
time after Tenant’s written notice of the need for such repairs or maintenance. Tenant waives its rights under any state or local law to terminate this Lease or to make such repairs at Landlord’s expense and agrees that the parties’
respective rights with respect to such matters shall be solely as set forth herein. Repairs required as the result of fire, earthquake, flood, vandalism, war, or similar cause of damage or destruction shall be controlled by Section 18.

 14. Tenant’s Repairs. Subject to Section 13 hereof, Tenant, at its expense, shall repair, replace and maintain in
good condition all portions of the Premises, including, without limitation, entries, doors, ceilings, interior windows, interior walls, and the interior side of demising walls. Should Tenant fail to make any such repair or replacement or fail to
maintain the Premises, Landlord shall give Tenant notice of such failure. If Tenant fails to commence cure of such failure within 10 days of Landlord’s notice, and thereafter diligently prosecute such cure to completion, Landlord may perform
such work and shall be reimbursed by Tenant within 10 days after demand therefor; provided, however, that if such failure by Tenant creates or could create an emergency, Landlord may immediately commence cure of such failure and shall thereafter be
entitled to recover the costs of such cure from Tenant. Subject to Sections 17 and 18, Tenant shall bear the full uninsured cost of any repair or replacement to any part of the Project that results from damage caused by Tenant or any
Tenant Party and any repair that benefits only the Premises. 
 15. Mechanic’s Liens. Tenant shall discharge, by bond or
otherwise, any mechanic’s lien filed against the Premises or against the Project for work claimed to have been done for, or materials claimed to have been furnished to, Tenant within 10 days after the filing thereof, at Tenant’s sole cost
and shall otherwise keep the Premises and the Project free from any liens arising out of work performed, materials furnished or obligations incurred by Tenant. Should Tenant fail to discharge any lien described herein, Landlord shall have the right,
but not the obligation, to pay such claim or post a bond or otherwise provide security to eliminate the lien as a claim against title to the Project and the cost thereof shall be immediately due from Tenant as Additional Rent. If Tenant shall lease
or finance the acquisition of office equipment, furnishings, or other personal property of a removable nature utilized by Tenant in the operation of Tenant’s business, Tenant warrants that any Uniform Commercial Code Financing Statement filed
as a matter of public record by any lessor or creditor of Tenant will upon its face or by exhibit thereto indicate that such Financing Statement is applicable only to removable personal property of Tenant located within the Premises. In no event
shall the address of the Project be furnished on the statement without qualifying language as to applicability of the lien only to removable personal property, located in an identified suite held by Tenant. 

16. Indemnification. Tenant hereby indemnifies and agrees to defend, save and hold Landlord harmless from and against any and all
Claims for injury or death to persons or damage to property occurring within or about the Premises, arising directly or indirectly out of use or occupancy of the Premises or a breach or default by Tenant in the performance of any of its obligations
hereunder, except to the extent caused by the willful misconduct or negligence of Landlord. Landlord shall not be 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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liable to Tenant for, and Tenant assumes all risk of damage to, personal property (including, without limitation, loss of records kept within the Premises). Tenant further waives any and all
Claims for injury to Tenant’s business or loss of income relating to any such damage or destruction of personal property (including, without limitation, any loss of records). Landlord shall not be liable for any damages arising from any act,
omission or neglect of any tenant in the Project or of any other third party. 
 17. Insurance. Landlord shall maintain all risk
property and, if applicable, sprinkler damage insurance covering the full replacement cost of the Project. Landlord shall further procure and maintain commercial general liability insurance with a single loss limit of not less than $2,000,000 for
bodily injury and property damage with respect to the Project. Landlord may, but is not obligated to, maintain such other insurance and additional coverages as it may deem necessary, including, but not limited to, flood, environmental hazard and
earthquake, loss or failure of building equipment, errors and omissions, rental loss during the period of repair or rebuilding, workers’ compensation insurance and fidelity bonds for employees employed to perform services and insurance for any
improvements installed by Tenant or which are in addition to the standard improvements customarily furnished by Landlord without regard to whether or not such are made a part of the Project. All such insurance shall be included as part of the
Operating Expenses. The Project may be included in a. blanket policy (in which case the cost of such insurance allocable to the Project will be determined by Landlord based upon the insurer’s cost calculations). Tenant shall also reimburse
Landlord for any increased premiums or additional insurance which Landlord reasonably deems necessary as a result of Tenant’s use of the Premises. 

Tenant, at its sole cost and expense, shall maintain during the Term: all risk property insurance with business interruption and extra expense
coverage, covering the full replacement cost of all property and improvements installed or placed in the Premises by Tenant at Tenant’s expense; workers’ compensation insurance with no less than the minimum limits required by law;
employer’s liability insurance with such limits as required by law; and commercial general liability insurance, with a minimum limit of not less than $2,000,000 per occurrence for bodily injury and property damage with respect to the Premises.
The commercial general liability insurance policy shall name Alexandria Real Estate Equities, Inc., and Landlord, its officers, directors, employees, managers, agents, invitees and contractors (collectively, “Landlord Parties”), as
additional insureds; insure on an occurrence and not a claims-made basis; be issued by insurance companies which have a rating of not less than policyholder rating of A and financial category rating of at least Class X in “Best’s
Insurance Guide”; shall not be cancelable for nonpayment of premium unless 10 days prior written notice shall have been given to Landlord from the insurer; not contain a hostile fire exclusion; contain a contractual liability endorsement; and
provide primary coverage to Landlord (any policy issued to Landlord providing duplicate or similar coverage shall be deemed excess over Tenant’s policies). Copies of such policies (if requested by Landlord), or certificates of insurance showing
the limits of coverage required hereunder and showing Landlord as an additional insured, along with reasonable evidence of the payment of premiums for the applicable period, shall be delivered to Landlord by Tenant prior to (i) the earlier to
occur of (x) the Commencement Date, or (y) the date that Tenant accesses the Premises under this Lease, and (ii) each renewal of said insurance. Tenant’s policy may be a “blanket policy” with an aggregate per location
endorsement which specifically provides that the amount of insurance shall not be prejudiced by other losses covered by the policy. Tenant shall, at least 5 days prior to the expiration of such policies, furnish Landlord with renewal certificates.

 In each instance where insurance is to name Landlord as an additional insured, Tenant shall upon written request of Landlord also
designate and furnish certificates so evidencing Landlord as additional insured to: (i) any lender of Landlord holding a security interest in the Project or any portion thereof, (ii) the landlord under any lease wherein Landlord is tenant
of the real property on which the Project is located, if the interest of Landlord is or shall become that of a tenant under a ground or other underlying lease rather than that of a fee owner, and/or (iii) any management company retained by
Landlord to manage the Project. 
 The property insurance obtained by Landlord and Tenant shall include a waiver of subrogation by the
insurers and all rights based upon an assignment from its insured, against Landlord or Tenant, and their respective officers, directors, employees, managers, agents, invitees and contractors (“Related 


  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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Parties”), in connection with any loss or damage thereby insured against. Neither party nor its respective Related Parties shall be liable to the other for loss or damage caused by
any risk insured against under property insurance required to be maintained hereunder, and each party waives any claims against the other party, and its respective Related Parties, for such loss or damage. The failure of a party to insure its
property shall not void this waiver. Landlord and its respective Related Parties shall not be liable for, and Tenant hereby waives all claims against such parties for, business interruption and losses occasioned thereby sustained by Tenant or any
person claiming through Tenant resulting from any accident or occurrence in or upon the Premises or the Project from any cause whatsoever. If the foregoing waivers shall contravene any law with respect to exculpatory agreements, the liability of
Landlord or Tenant shall be deemed not released but shall be secondary to the other’s insurer. 
 Landlord may require insurance policy
limits to be raised to conform with requirements of Landlord’s lender and/or to bring coverage limits to levels then being generally required of new tenants within the Project; provided, however, that the increased amount of coverage is
consistent with coverage amounts then being required by institutional owners of similar projects with tenants occupying similar size premises in the geographical area in which the Project is located. 

18. Restoration. If, at any time during the Term, the Project or the Premises are damaged or destroyed by a fire or other casualty,
Landlord shall notify Tenant within 60 days after discovery of such damage as to the amount of time Landlord reasonably estimates it will take to restore the Project or the Premises, as applicable (the “Restoration Period”). If the
Restoration Period is estimated to exceed 12 months (the “Maximum Restoration Period”), Landlord may, in such notice, elect to terminate this Lease as of the date that is 75 days after the date of discovery of such damage or
destruction; provided, however, that notwithstanding Landlord’s election to restore, Tenant may elect to terminate this Lease by written notice to Landlord delivered within 5 business days of receipt of a notice from Landlord
estimating a Restoration Period for the Premises longer than the Maximum Restoration Period. Unless either Landlord or Tenant so elects to terminate this Lease, Landlord shall, subject to receipt of sufficient insurance proceeds (with any deductible
to be treated as a current Operating Expense), promptly restore the Premises (excluding the improvements installed by Tenant or by Landlord and paid for by Tenant), subject to delays arising from the collection of insurance proceeds, from Force
Majeure events or as needed to obtain any license, clearance or other authorization of any kind required to enter into and restore the Premises issued by any Governmental Authority having jurisdiction over the use, storage, handling, treatment,
generation, release, disposal, removal or remediation of Hazardous Materials (as defined in Section 30) in, on or about the Premises (collectively referred to herein as “Hazardous Materials Clearances”); provided,
however, that if repair or restoration of the Premises is not substantially complete as of the end of the Maximum Restoration Period or, if longer, the Restoration Period, Landlord may, in its sole and absolute discretion, elect not to
proceed with such repair and restoration, or Tenant may by written notice to Landlord delivered within 5 business days of the expiration of the Maximum Restoration Period or, if longer, the Restoration Period, elect to terminate this Lease, in which
event Landlord shall be relieved of its obligation to make such repairs or restoration and this Lease shall terminate as of the date that is 75 days after the later of: (i) discovery of such damage or destruction, or (ii) the date all
required Hazardous Materials Clearances are obtained, but Landlord shall retain any Rent paid and the right to any Rent payable by Tenant prior to such election by Landlord or Tenant. 

Tenant, at its expense, shall promptly perform, subject to delays arising from the collection of insurance proceeds, from Force Majeure (as
defined in Section 34) events or to obtain Hazardous Material Clearances, all repairs or restoration not required to be done by Landlord and shall promptly reenter the Premises and commence doing business in accordance with this Lease.
Notwithstanding the foregoing, either Landlord or Tenant may terminate this Lease upon written notice to the other if the Premises are damaged during the last year of the Term and Landlord reasonably estimates that it will take more than 2 months to
repair such damage; provided, however, that such notice is delivered within 10 business days after the date that Landlord provides Tenant with written notice of the estimated Restoration Period. Notwithstanding anything to the contrary contained
herein, Landlord shall also have the right to terminate this Lease if insurance proceeds are not available for such restoration. Rent shall be abated from the date all required Hazardous Material Clearances are obtained until the Premises are


  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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repaired and restored, in the proportion which the area of the Premises, if any, which is not usable by Tenant bears to the total area of the Premises, unless Landlord provides Tenant with
other space during the period of repair that is suitable for the temporary conduct of Tenant’s business. Such abatement shall be the sole remedy of Tenant, and except as otherwise provided in this Section 18, Tenant waives any right
to terminate the Lease by reason of damage or casualty loss. 
 The provisions of this Lease, including this Section 18,
constitute an express agreement between Landlord and Tenant with respect to any and all damage to, or destruction of, all or any part of the Premises, or any other portion of the Project, and any statute or regulation which is now or may hereafter
be in effect shall have no application to this Lease or any damage or destruction to all or any part of the Premises or any other portion of the Project, the parties hereto expressly agreeing that this Section 18 sets forth their entire
understanding and agreement with respect to such matters. 
 19. Condemnation. If the whole or any material part of the Premises or
the Project is taken for any public or quasi-public use under governmental law, ordinance, or regulation, or by right of eminent domain, or by private purchase in lieu thereof (a “Taking” or “Taken”), and the Taking
would in Landlord’s reasonable judgment, materially interfere with or impair Landlord’s ownership or operation of the Project or would in the reasonable judgment of Landlord and Tenant either prevent or materially interfere with
Tenant’s use of the Premises (as resolved, if the parties are unable to agree, by arbitration by a single arbitrator with the qualifications and experience appropriate to resolve the matter and appointed pursuant to and acting in accordance
with the rules of the American Arbitration Association), then upon written notice by Landlord or Tenant to the other this Lease shall terminate and Rent shall be apportioned as of said date. Landlord and Tenant agree that a Taking of more than 60%
of the Premises would constitute a material interference of Tenant’s use of the Premises. If part of the Premises shall be Taken, and this Lease is not terminated as provided above, Landlord shall promptly restore the Premises and the Project
as nearly as is commercially reasonable under the circumstances to their condition prior to such partial Taking and the rentable square footage of the Building, the rentable square footage of the Premises, Tenant’s Share of Operating Expenses
and the Rent payable hereunder during the unexpired Term shall be reduced to such extent as may be fair and reasonable under the circumstances. Upon any such Taking, Landlord shall be entitled to receive the entire price or award from any such
Taking without any payment to Tenant, and Tenant hereby assigns to Landlord Tenant’s interest, if any, in such award. Tenant shall have the right, to the extent that same shall not diminish Landlord’s award, to make a separate claim
against the condemning authority (but not Landlord) for such compensation as may be separately awarded or recoverable by Tenant for moving expenses and damage to Tenant’s trade fixtures, if a separate award for such items is made to Tenant.
Tenant hereby waives any and all rights it might otherwise have pursuant to any provision of state law to terminate this Lease upon a partial Taking of the Premises or the Project. 

20. Events of Default. Each of the following events shall be a default (“Default”) by Tenant under this Lease: 

(a) Payment Defaults. Tenant shall fail to pay any installment of Rent or any other payment hereunder when due; provided, however, that
Landlord will give Tenant notice and an opportunity to cure any failure to pay Rent within 5 days of any such notice not more than once in any 12 month period and Tenant agrees that such notice shall be in lieu of and not in addition to, or shall be
deemed to be, any notice required by law. 
 (b) Insurance. Any insurance required to be maintained by Tenant pursuant to this Lease
shall be canceled or terminated or shall expire or shall be reduced or materially changed, or Landlord shall receive a notice of nonrenewal of any such insurance and Tenant shall fail to obtain replacement insurance before the expiration of the
current coverage. 
 (c) Abandonment. Tenant shall abandon the Premises. Tenant shall not be deemed to have abandoned the Premises if
(i) Tenant provides Landlord with reasonable advance notice prior to vacating and, at the time of vacating the Premises, Tenant completes Tenant’s obligations with respect to 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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the Surrender Plan in compliance with Section 28, (ii) Tenant has made reasonable arrangements with Landlord for the security of the Premises for the balance of the Term, and
(iii) Tenant continues during the balance of the Term to satisfy all of its obligations under the Lease as they come due. 
 (d)
Improper Transfer. Tenant shall assign, sublease or otherwise transfer or attempt to transfer all or any portion of Tenant’s interest in this Lease or the Premises except as expressly permitted herein, or Tenant’s interest in this
Lease shall be attached, executed upon, or otherwise judicially seized and such action is not released within 90 days of the action. 
 (e)
Liens. Tenant shall fail to discharge or otherwise obtain the release of any lien placed upon the Premises in violation of this Lease within 10 days after any such lien is filed against the Premises. 

(f) Insolvency Events. Tenant or any guarantor or surety of Tenant’s obligations hereunder shall: (A) make a general
assignment for the benefit of creditors; (B) commence any case, proceeding or other action seeking to have an order for relief entered on its behalf as a debtor or to adjudicate it a bankrupt or insolvent, or seeking reorganization,
arrangement, adjustment, liquidation, dissolution or composition of it or its debts or seeking appointment of a receiver, trustee, custodian or other similar official for it or for all or of any substantial part of its property (collectively a
“Proceeding for Relief”); (C) become the subject of any Proceeding for Relief which is not dismissed within 90 days of its filing or entry; or (D) die or suffer a legal disability (if Tenant, guarantor, or
surety is an individual) or be dissolved or otherwise fail to maintain its legal existence (if Tenant, guarantor or surety is a corporation, partnership or other entity). 

(g) Estoppel Certificate or Subordination Agreement. Tenant fails to execute any document required from Tenant under Sections 23
or 27 within 5 days after a second notice requesting such document. 
 (h) Other Defaults. Tenant shall fail to comply with
any provision of this Lease other than those specifically referred to in this Section 20, and, except as otherwise expressly provided herein, such failure shall continue for a period of 10 days after written notice thereof from Landlord
to Tenant. 
 Any notice given under Section 20(h) hereof shall: (i) specify the alleged default, (ii) demand that Tenant cure such
default, (iii) be in lieu of, and not in addition to, or shall be deemed to be, any notice required under any provision of applicable law, and (iv) not be deemed a forfeiture or a termination of this Lease unless Landlord elects otherwise
in such notice; provided that if the nature of Tenant’s default pursuant to Section 20(h) is such that it cannot be cured by the payment of money and reasonably requires more than 10 days to cure, then Tenant shall not be
deemed to be in default if Tenant commences such cure within said 10 day period and thereafter diligently prosecutes the same to completion; provided, however, that such cure shall be completed no later than 30 days from the date of
Landlord’s notice. 
 21. Landlord’s Remedies.  

(a) Payment By Landlord; Interest. Upon a Default by Tenant hereunder, Landlord may, without waiving or releasing any obligation of
Tenant hereunder, make such payment or perform such act. All sums so paid or incurred by Landlord, together with interest thereon, from the date such sums were paid or incurred, at the annual rate equal to 12% per annum or the highest rate permitted
by law (the “Default Rate”), whichever is less, shall be payable to Landlord on demand as Additional Rent. 
 (b) Late
Payment Rent. Late payment by Tenant to Landlord of Rent and other sums due will cause Landlord to incur costs not contemplated by this Lease, the exact amount of which will be extremely difficult and impracticable to ascertain. Such costs
include, but are not limited to, processing and accounting charges and late charges which may be imposed on Landlord under any Mortgage covering the Premises. Therefore, if any installment of Rent due from Tenant is not received by Landlord within 5
days after the date such payment is due, Tenant shall pay to Landlord an additional sum equal to 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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6% of the overdue Rent as a late charge. Notwithstanding the foregoing, before assessing a late charge the first time in any calendar year, Landlord shall provide Tenant written notice of the
delinquency and will waive the right if Tenant pays such delinquency within 5 days thereafter. The parties agree that this late charge represents a fair and reasonable estimate of the costs Landlord will incur by reason of late payment by Tenant. In
addition to the late charge, Rent not paid when due shall bear interest at the Default Rate from the 5th day after the date due until paid. 

(c) Remedies. Upon the occurrence and during the continuance of a Default, Landlord, at its option, without further notice or demand to
Tenant, shall have in addition to all other rights and remedies provided in this Lease, at law or in equity, the option to pursue any one or more of the following remedies, each and all of which shall be cumulative and nonexclusive, without any
notice or demand whatsoever (except as otherwise expressly provided in Section 21(c)(v) with respect to Landlord’s Lump Sum Election). No cure in whole or in part of such Default by Tenant after Landlord has taken any action beyond
giving Tenant notice of such Default to pursue any remedy provided for herein (including retaining counsel to file an action or otherwise pursue any remedies) shall in any way affect Landlord’s right to pursue such remedy or any other remedy
provided Landlord herein or under law or in equity, unless Landlord, in its sole discretion, elects to waive such Default. 

(i) This Lease and the Term and estate hereby granted are subject to the limitation that whenever a Default shall have happened
and be continuing, Landlord shall have the right, at its election, then or thereafter while any such Default shall continue and notwithstanding the fact that Landlord may have some other remedy hereunder or at law or in equity, to give Tenant
written notice of Landlord’s intention to terminate this Lease on a date specified in such notice, which date shall be not less than 5 days after the giving of such notice, and upon the date so specified, this Lease and the estate hereby
granted shall expire and terminate with the same force and effect as if the date specified in such notice were the date hereinbefore fixed for the expiration of this Lease, and all right of Tenant hereunder shall expire and terminate, and Tenant
shall be liable as hereinafter in this Section 21(c) provided. If any such notice is given, Landlord shall have, on such date so specified, the right of re-entry and possession of the Premises and
the right to remove all persons and property therefrom and to store such property in a warehouse or elsewhere at the risk and expense, and for the account, of Tenant. Should Landlord elect to re-enter as
herein provided or should Landlord take possession pursuant to legal proceedings or pursuant to any notice provided for by law, Landlord may, subject to Section 21(c)(ii) from time to time re-let
the Premises or any part thereof for such term or terms and at such rental or rentals and upon such terms and conditions as Landlord may deem advisable, with the right to make commercially reasonable alterations in and repairs to the Premises. 

(ii) Landlord shall be deemed to have satisfied any obligation to mitigate its damages by hiring an experienced commercial real
estate broker to market the Premises and directing such broker to advertise and show the Premises to prospective tenants. 

(iii) In the event of any termination of this Lease as in this Section 21 provided or as required or permitted by
law or in equity, Tenant shall forthwith quit and surrender the Premises to Landlord, and Landlord may, without further notice, enter upon, re-enter, possess and repossess the same by summary proceedings,
ejectment or otherwise, and again have, repossess and enjoy the same as if this Lease had not been made, and in any such event Tenant and no person claiming through or under Tenant by virtue of any law or an order of any court shall be entitled to
possession or to remain in possession of the Premises. 
 (iv) If this Lease is terminated or if Landlord shall re-enter the Premises as aforesaid, or in the event of the termination of this Lease, or of re-entry, by or under any proceeding or action or any provision of law by reason of
a Default by Tenant, Tenant covenants and agrees forthwith to pay and be liable for, on the days originally fixed in this Lease for the payment thereof, amounts equal to the installments of Base Rent and all Additional Rent as they would, under the
terms of this Lease become due if this Lease had not been terminated or if Landlord 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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had not entered or re-entered, as aforesaid, and whether the Premises be relet or remain vacant, in whole or in part, or for a period less than the
remainder of the Term, or for the whole thereof, but in the event that the Premises be relet by Landlord, Tenant shall be entitled to a credit in the net amount of rent and other charges received by Landlord in reletting, after deduction of all of
Landlord’s expenses incurred in reletting the Premises (including, without limitation, tenant improvement, demising and remodeling costs, brokerage fees and the like), and in collecting the rent in connection therewith, in the following manner:
Amounts received by Landlord after reletting, if any, shall first be applied against such Landlord’s expenses, until the same are recovered, and until such recovery, Tenant shall pay, as of each day when a payment would fall due under this
Lease, the amount which Tenant is obligated to pay under the terms of this Lease (Tenant’s liability prior to any such reletting and such recovery by Landlord no in any way to be diminished as a result of the fact that such reletting might be
for a rent higher than the rent provided for in this Lease); when and if such expenses have been completely recovered by Landlord, the amounts received from reletting by Landlord as have not previously been applied shall be credited against
Tenant’s obligations as of each day when a payment would fall due under this Lease, and only the net amount thereof shall be payable by Tenant. Further, Tenant shall not be entitled to any credit of any kind for any period after the date when
the Term of this Lease is scheduled to expire according to its terms. 
 Actions, proceedings or suits for the recovery of damages, whether liquidated or
other damages, under this Lease, or any installments thereof, may be brought by Landlord from time to time at its election, and nothing contained herein shall be deemed to require Landlord to postpone suit until the date when the Term of this Lease
would have expired if it had not been terminated hereunder. 
 (v) In addition, Landlord, at its election, notwithstanding
any other provision of this Lease, by written notice to Tenant (the “Lump Sum Election”), shall be entitled to recover from Tenant, as and for liquidated damages, at any time following any termination of this Lease, a lump sum
payment representing, at the time of Landlord’s written notice of its Lump Sum Election, the sum of: 
 (A) the then
present value (calculated in accordance with accepted financial practice using as the discount rate the yield to maturity on United States Treasury Notes as set forth below) of the amount of unpaid Base Rent and Additional Rent that would have been
payable pursuant to this Lease for the remainder of the Term following Landlord’s Lump Sum Election if this Lease had not been terminated, and 

(B) all other damages and expenses (including attorneys’ fees and expenses), if any, which Landlord shall have sustained
by reason of the breach of any provision of this Lease; less 
 (C) the then present value (calculated in accordance with
accepted financial practice using as the discount rate the yield to maturity on United States Treasury Notes as set forth below) of the aggregate net fair market rent plus additional charges payable for the Premises (if less than the then present
value of Base Rent and Additional Rent that would have been payable pursuant to this Lease) for the remainder of the Term following Landlord’s Lump Sum Election, calculated as of the date of Landlord’s Lump Sum Election, and taking into
account reasonable estimates of the future costs to relet any then vacant portions of the Premises (except to the extent that Tenant has actually paid such costs pursuant to this Section 21) in order to calculate the net rental revenue
that Landlord may expect to obtain for the Premises for the balance of the Term. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 Landlord’s recovery under its Lump Sum Election shall be in addition to Tenant’s
obligations to pay Base Rent and Additional Rent due and costs incurred prior to the date of Landlord’s Lump Sum Election, and in lieu of any Base Rent and Additional Rent which would otherwise have been due under this Section from and after
the date of Landlord’s Lump Sum Election. The yield to maturity on United States Treasury Notes having a maturity date that is nearest the date that would have been the last day of the Term of the Lease, as reported in the Wall Street
Journal or a comparable publication if it ceases to publish such yields, shall be used in calculating present values for purposes of Landlord’s Lump Sum Election. For the purposes of this Section, if Landlord makes the Lump Sum Election to
recover liquidated damages in accordance with this Section, the total Additional Rent shall be computed by assuming Tenant’s Share of Operating Expenses and other Additional Rent to be the same as were payable for the twelve (12) calendar
months (or if less than twelve (12) calendar months have been elapsed since the date hereof, the partial year) immediately preceding the date of Landlord’s Lump Sum election. 

In the event Landlord makes a Lump Sum Election pursuant to this Section 21(c)(v) and Landlord subsequently relets
the Premises, Tenant shall be entitled to a credit in the net amount of rent and other charges to be received by Landlord in reletting the Premises, after deduction of all of Landlord’s reasonable expenses incurred in reletting the Premises
(including, without limitation, tenant improvement, demising and remodeling costs, brokerage fees and the like). This credit shall offset the lump sum amount otherwise owed by Tenant under this Section 21 (c)(v) and, in the event Tenant
has already paid the lump sum hereunder, Landlord shall refund such credit amount to Tenant within a reasonable period. 

(vi) Nothing herein contained shall limit or prejudice the right of Landlord, in any bankruptcy or insolvency proceeding, to
prove for and obtain as liquidated damages by reason of such termination an amount equal to the maximum allowed by any bankruptcy or insolvency proceedings, or to prove for and obtain as liquidated damages by reason of such termination, an amount
equal to the maximum allowed by any statute or rule of law, whether such amount shall be greater or less than the excess referred to above. · 

(vii) Nothing in this Section 21 shall be deemed to affect the right of either party to indemnifications pursuant
to this Lease. 
 (viii) If Landlord terminates this Lease upon the occurrence of a Default, Tenant will quit and surrender
the Premises to Landlord or its agents, and Landlord may, without further notice, enter upon, re-enter and repossess the Premises by summary proceedings, ejectment or otherwise. The words “enter”, “re-enter”, and “re-entry” are not restricted to their technical legal meanings. 

(ix) If either party shall be in default in the observance or performance of any provision of this Lease, and an action shall
be brought for the enforcement thereof in which it shall be determined that such party was in default, the party in default shall pay to the other party all reasonable, out of pocket fees, costs and other expenses which may become payable as a
result thereof or in connection therewith, including reasonable attorneys’ fees and expenses. 
 (x) If Default by
Tenant shall occur in the keeping, observance or performance of any covenant, agreement, term, provision or condition herein contained, Landlord, without thereby waiving such Default, may perform the same for the account and at the expense of Tenant
(a) immediately or at any time thereafter and with only such notice, if any, as may be practicable under the circumstances in the case of Emergency or in case such default will result in a violation of any legal or insurance requirements, or in
the imposition of any lien against all or any portion of the Premises or the Project not bonded over to Landlord’s satisfaction by Tenant within 10 business days after delivery of notice by Landlord to Tenant, and (b) in any other case if
such default continues after any applicable notice and cure period provided in Section 21. All reasonable costs and expenses incurred by Landlord in connection with any such performance by it for the account of Tenant and also all
reasonable costs and expenses, including attorneys’ fees and disbursements incurred by Landlord in any action or proceeding (including any summary 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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dispossess proceeding) brought by Landlord to enforce any obligation of Tenant under this Lease and/or right of Landlord in or to the Premises, shall be paid by Tenant to Landlord within 10 days
after demand. Landlord shall not be liable for, nor shall Tenant’s obligations hereunder be diminished because of, Landlord’s failure to relet the Premises or collect rent due in respect of such reletting or otherwise to mitigate any
damages arising by reason of Tenant’s Default. Landlord shall, however, use commercially reasonable efforts to mitigate the damages arising by reason of the termination of this Lease as a result of a Default by Tenant; provided, however, that
in no event shall mitigation require Landlord to consider, among other things, (i) any tenant which does not satisfy Landlord’s then current underwriting criteria, in the exercise of Landlord’s sole and absolute discretion, for
comparable size premises, (ii) subdividing the Premises unless Landlord elects in its sole and absolute discretion to do so, (iii) any change in use of the Premises or any alterations which would lessen the value of the leasehold
improvements, (iv) granting any tenant improvement allowances, free rent or other lease concessions, or (v) accepting any tenant if Landlord would have the right to reject such tenant if such tenant were a proposed assignee or sublessee of
Tenant including, without limitation, considering the factors described in Section 22(b). 
 (xi) Independent of the
exercise of any other remedy of Landlord hereunder or under applicable law, Landlord may conduct an environmental test of the Premises as generally described in Section 30(c). 

(xii) In the event that Tenant is in breach or Default under this Lease, whether or not Landlord exercises its right to
terminate or any other remedy, Tenant shall reimburse Landlord upon demand for any out of pocket costs and expenses that Landlord may incur in connection with any such breach or Default, as provided in this Section 21 (c). Such costs
shall include legal fees and costs incurred for the negotiation of a settlement, enforcement of rights or otherwise. Tenant shall also indemnify Landlord against and hold Landlord harmless from all costs, expenses, demands and liability, including
without limitation, legal fees and costs Landlord shall incur if Landlord shall become or be made a party to any claim or action instituted by Tenant against any third party, or by or against any person holding any interest under or using the
Premises by license of or agreement with Tenant. 
 Except as otherwise provided in this Section 21, no right or remedy herein
conferred upon or reserved to Landlord is intended to be exclusive of any other right or remedy, and every right and remedy shall be cumulative and in addition to any other legal or equitable right or remedy given hereunder, or now or hereafter
existing. No waiver by either party of any provision of this Lease shall be deemed to have been made unless expressly so made in writing by the party waiving such provision. Landlord and Tenant each shall be entitled, to the extent permitted by law,
to seek injunctive relief in case of the violation, or attempted or threatened violation, of any provision of this Lease, or to seek a decree compelling observance or performance of any provision of this Lease, or to seek any other legal or
equitable remedy. 
 22. Assignment and Subletting.  

(a) General Prohibition. Without Landlord’s prior written consent subject to and on the conditions described in this
Section 22, Tenant shall not, directly or indirectly, voluntarily or by operation of law, assign this Lease or sublease the Premises or any part thereof or mortgage, pledge, or hypothecate its leasehold interest or grant any concession or
license within the Premises, and any attempt to do any of the foregoing shall be void and of no effect. If Tenant is a corporation, partnership or limited liability company, the shares or other ownership interests thereof which are not actively
traded upon a stock exchange or in the over-the-counter market, a transfer or series of transfers whereby 50% or more of the issued and outstanding shares or other
ownership interests of such corporation are, or voting control is, transferred (but excepting transfers upon deaths of individual owners) from a person or persons or entity or entities which were owners thereof at time of execution of this Lease to
persons or entities who were not owners of shares or other ownership interests of the corporation, partnership or 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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limited liability company at time of execution of this Lease, shall be deemed an assignment of this Lease requiring the consent of Landlord as provided in this Section 22.
Notwithstanding the foregoing, Tenant shall have the right to obtain financing from institutional investors (including venture capital funding and corporate partners) which regularly invest in private biotechnology companies which results in a
change in control of Tenant without such change of control constituting an assignment under this Section 22 requiring Landlord consent, provided that (i) Tenant notifies Landlord in writing of the financing at least 5 business days
prior to the closing of the financing, and (ii) provided that in no event shall such financing result in a change in use of the Premises from the use contemplated by Tenant at the commencement of the Term. 

(b) Permitted Transfers. If Tenant desires to assign, sublease, hypothecate or otherwise transfer this Lease or sublet the Premises
other than pursuant to a Permitted Assignment (as defined below), then at least 15 business days, but not more than 45 business days, before the date Tenant desires the assignment or sublease to be effective (the “Assignment Date”),
Tenant shall give Landlord a notice (the “Assignment Notice”) containing such information about the proposed assignee or sublessee, including the proposed use of the Premises and any Hazardous Materials proposed to be used,
stored handled, treated, generated in or released or disposed of from the Premises, the Assignment Date, any relationship between Tenant and the proposed assignee or sublessee, and all material terms and conditions of the proposed assignment or
sublease, including a copy of any proposed assignment or sublease in its final form, and such other information as Landlord may deem reasonably necessary or appropriate to its consideration whether to grant its consent. Landlord may, by giving
written notice to Tenant within 15 business days after receipt of the Assignment Notice: (i) grant such consent (provided that Landlord shall further have the right to review and approve or disapprove the proposed form of sublease prior to the
effective date of any such subletting), (ii) refuse such consent, in its reasonable discretion; or (iii) terminate this Lease with respect to the space described in the Assignment Notice as of the Assignment Date (an “Assignment
Termination”). Among other reasons, it shall be reasonable for Landlord to withhold its consent in any of these instances: (1) the proposed assignee or subtenant is a governmental agency; (2) in Landlord’s reasonable
judgment, the use of the Premises by the proposed assignee or subtenant would entail any alterations that would lessen the value of the leasehold improvements in the Premises, or would require increased services by Landlord; (3) in
Landlord’s reasonable judgment, the proposed assignee or subtenant is engaged in areas of scientific research or other business concerns that are controversial; (4) in Landlord’s reasonable judgment, the proposed assignee or subtenant
lacks the creditworthiness to support the financial obligations it will incur under the proposed assignment or sublease; (5) in Landlord’s reasonable judgment, the character, reputation, or business of the proposed assignee or subtenant is
inconsistent with the desired tenant-mix or the quality of other tenancies in the Project or is inconsistent with the type and quality of the nature of the Building; (6) Landlord has received from any
prior landlord to the proposed assignee or subtenant a negative report concerning such prior landlord’s experience with the proposed assignee or subtenant; (7) Landlord has experienced previous defaults by or is in litigation with the
proposed assignee or subtenant; (8) the use of the Premises by the proposed assignee or subtenant will violate any applicable Legal Requirement; (9) the proposed assignee or subtenant, or any entity that, directly or indirectly, controls,
is controlled by, or is under common control with the proposed assignee or subtenant, is then an occupant of the Project; (10) the proposed assignee or subtenant is an entity with whom Landlord is negotiating to lease space in the Project; or
(11) the assignment or sublease is prohibited by Landlord’s lender. If Landlord delivers notice of its election to exercise an Assignment Termination, Tenant shall have the right to withdraw such Assignment Notice by written notice to
Landlord of such election within 5 business days after Landlord’s notice electing to exercise the Assignment Termination. If Tenant withdraws such Assignment Notice, this Lease shall continue in full force and effect. If Tenant does not
withdraw such Assignment Notice, this Lease, and the term and estate herein granted, shall terminate as of the Assignment Date with respect to the space described in such Assignment Notice. No failure of Landlord to exercise any such option to
terminate this Lease, or to deliver a timely notice in response to the Assignment Notice, shall be deemed to be Landlord’s consent to the proposed assignment, sublease or other transfer. Tenant shall pay to Landlord a fee equal to One Thousand
Five Hundred Dollars ($1,500) in connection with its consideration of any Assignment Notice and/or its preparation or review of any consent documents. Notwithstanding the foregoing, Landlord’s consent to an assignment of this Lease or a
subletting of any portion of the Premises to any entity controlling, controlled by or under common 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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control with Tenant (a “Control Permitted Assignment”) shall not be required, provided that Landlord shall have the right to approve the form of any such sublease or assignment,
which approval shall not be unreasonably withheld, conditioned or delayed. In addition, Tenant shall have the right to assign this Lease, upon 10 days prior written notice to Landlord but without obtaining Landlord’s prior written consent, to a
corporation or other entity which is a successor-in-interest to Tenant, by way of merger, consolidation or corporate reorganization, or by the purchase of all or
substantially all of the assets or the ownership interests of Tenant provided that (i) such merger or consolidation, or such acquisition or assumption, as the case may be, is for a good business purpose and not principally for the purpose of
transferring the Lease, and (ii) the net worth (as determined in accordance with generally accepted accounting principles (“GAAP”)) of the assignee is not less than the greater of the net worth (as determined in accordance with
GAAP) of Tenant as of (A) the Commencement Date, or (B) as of the date of Tenant’s most current quarterly or annual financial statements, and (iii) such assignee shall agree in writing to assume all of the terms, covenants and
conditions of this Lease (a “Corporate Permitted Assignment”). Control Permitted Assignments and Corporate Permitted Assignments are hereinafter referred to as “Permitted Assignments.”  

(c) Additional Conditions. As a condition to any such assignment or subletting, whether or not Landlord’s consent is required,
Landlord may require: 
 (i) that any assignee or subtenant agree, in writing at the time of such assignment or subletting,
that if Landlord gives such party notice that Tenant is in default under this Lease, such party shall thereafter make all payments otherwise due Tenant directly to Landlord, which payments will be received by Landlord without any liability except to
credit such payment against those due under the Lease, and any such third party shall agree to attorn to Landlord or its successors and assigns should this Lease be terminated for any reason; provided, however, in no event shall
Landlord or its successors or assigns be obligated to accept such attornment; and 
 (ii) A list of Hazardous Materials,
certified by the proposed assignee or sublessee to be true and correct, which the proposed assignee or sublessee intends to use, store, handle, treat, generate in or release or dispose of from the Premises, together with copies of all documents
relating to such use, storage, handling, treatment, generation, release or disposal of Hazardous Materials by the proposed assignee or subtenant in the Premises or on the Project, prior to the proposed assignment or subletting, including, without
limitation: permits; approvals; reports and correspondence; storage and management plans; plans relating to the installation of any storage tanks to be installed in or under the Project (provided, said installation of tanks shall only be permitted
after Landlord has given its written consent to do so, which consent may be withheld in Landlord’s sole and absolute discretion); and all closure plans or any other documents required by any and all federal, state and local Governmental
Authorities for any storage tanks installed in, on or under the Project for the closure of any such tanks. Neither Tenant nor any such proposed assignee or subtenant is required, however, to provide Landlord with any portion(s) of the such documents
containing information of a proprietary nature which, in and of themselves, do not contain a reference to any Hazardous Materials or hazardous activities. 

(d) No Release of Tenant, Sharing of Excess Rents. Notwithstanding any assignment or subletting, Tenant and any guarantor or surety of
Tenant’s obligations under this Lease shall at all times remain fully and primarily responsible and liable for the payment of Rent and for compliance with all of Tenant’s other obligations under this Lease. If the Rent due and payable by a
sublessee or assignee (or a combination of the rental payable under such sublease or assignment plus any bonus or other consideration therefor or incident thereto in any form) exceeds the sum of the rental payable under this Lease, (excluding
however, any Rent payable under this Section) and actual and reasonable brokerage fees, legal costs and any design or construction fees directly related to and required pursuant to the terms of any such sublease) (“Excess Rent”),
then Tenant shall be bound and obligated to pay Landlord as Additional Rent hereunder 50% of such Excess Rent within 10 days following receipt thereof by Tenant. If Tenant shall sublet the Premises or any part thereof, Tenant hereby immediately
and irrevocably assigns to Landlord, as security for Tenant’s obligations under this Lease, all rent from any such subletting, and Landlord as assignee and as
attorney-in-fact for Tenant, or a receiver for Tenant appointed on Landlord’s application, may collect such rent and apply it toward Tenant’s obligations under
this Lease; except that, until the occurrence of a Default, Tenant shall have the right to collect such rent. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 (e) No Waiver. The consent by Landlord to an assignment or subletting shall not
relieve Tenant or any assignees of this Lease or any sublessees of the Premises from obtaining the consent of Landlord to any further assignment or subletting nor shall it release Tenant or any assignee or sublessee of Tenant from full and primary
liability under the Lease. The acceptance of Rent hereunder, or the acceptance of performance of any other term, covenant, or condition thereof, from any other person or entity shall not be deemed to be a waiver of any of the provisions of this
Lease or a consent to any subletting, assignment or other transfer of the Premises. 
 (f) Prior Conduct of Proposed Transferee.
Notwithstanding any other provision of this Section 22, if (i) the proposed assignee or sublessee of Tenant has been required by any prior landlord, lender or Governmental Authority to take remedial action in connection with
Hazardous Materials contaminating a property, where the contamination resulted from such party’s action or use of the property in question, (ii) the proposed assignee or sublessee is subject to an enforcement order issued by any
Governmental Authority in connection with the use, storage, handling, treatment, generation, release or disposal of Hazardous Materials (including, without limitation, any order related to the failure to make a required reporting to any Governmental
Authority), or (iii) because of the existence of a pre-existing environmental condition in the vicinity of or underlying the Project, the risk that Landlord would be targeted as a responsible party in
connection with the remediation of such pre-existing environmental condition would be materially increased or exacerbated by the proposed use of Hazardous Materials by such proposed assignee or sublessee,
Landlord shall have the absolute right to refuse to consent to any assignment or subletting to any such party. 
 23. Estoppel
Certificate. Tenant shall, within 10 business days of written notice from Landlord, execute, acknowledge and deliver a statement in writing in any form reasonably requested by a proposed lender or purchaser, (i) certifying that this Lease
is unmodified and in full force and effect (or, if modified, stating the nature of such modification and certifying that this Lease as so modified is in full force and effect) and the dates to which the rental and other charges are paid in advance,
if any, (ii) acknowledging that there are not any uncured defaults on the part of Landlord hereunder, or specifying such defaults if any are claimed, and (iii) setting forth such further information with respect to the status of this Lease
or the Premises as may be requested thereon. Any such statement may be relied upon by any prospective purchaser or encumbrancer of all or any portion of the real property of which the Premises are a part. Tenant’s failure to deliver such
statement within such time shall, at the option of Landlord, constitute a Default under this Lease, and, in any event, shall be conclusive upon Tenant that the Lease is in full force and effect and without modification except as may be represented
by Landlord in any certificate prepared by Landlord and delivered to Tenant for execution. 
 24. Quiet Enjoyment. So long as Tenant
is not in Default under this Lease, Tenant shall, subject to the terms of this Lease, at all times during the Term, have peaceful and quiet enjoyment of the Premises against any person claiming by, through or under Landlord. 

25. Prorations. All prorations required or permitted to be made hereunder shall be made on the basis of a 360 day year and 30 day
months. 
 26. Rules and Regulations. Tenant shall, at all times during the Term and any extension thereof, comply with all
reasonable rules and regulations at any time or from time to time established by Landlord covering use of the Premises and the Project. The current rules and regulations are attached hereto as Exhibit E. If there is any conflict between said
rules and regulations and other provisions of this Lease, the terms and provisions of this Lease shall control. Landlord shall not have any liability or obligation for the breach of any rules or regulations by other tenants in the Project and shall
not enforce such rules and regulations in a discriminatory manner. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 27. Subordination. This Lease and Tenant’s interest and rights hereunder are
hereby made and shall be subject and subordinate at all times to the lien of any Mortgage now existing or hereafter created on or against the Project or the Premises, and all amendments, restatements, renewals, modifications, consolidations,
refinancing, assignments and extensions thereof, without the necessity of any further instrument or act on the part of Tenant; provided, however that so long as there is no Default hereunder, Tenant’s right to possession of the
Premises shall not be disturbed by the Holder of any such Mortgage. Tenant agrees, at the election of the Holder of any such Mortgage, to attorn to any such Holder. Tenant agrees upon demand to execute, acknowledge and deliver such instruments,
confirming such subordination, and such instruments of attornment as shall be requested by any such Holder, provided any such instruments contain appropriate non-disturbance provisions assuring Tenant’s
quiet enjoyment of the Premises as set forth in Section 24 hereof. Tenant hereby appoints Landlord attorney-in-fact for Tenant irrevocably (such power of
attorney being coupled with an interest) to execute, acknowledge and deliver any such instrument and instruments for and in the name of Tenant and to cause any such instrument to be recorded. Notwithstanding the foregoing, any such Holder may at any
time subordinate its Mortgage to this Lease, without Tenant’s consent, by notice in writing to Tenant, and thereupon this Lease shall be deemed prior to such Mortgage without regard to their respective dates of execution, delivery or recording
and in that event such Holder shall have the same rights with respect to this Lease as though this Lease had been executed prior to the execution, delivery and recording of such Mortgage and had been assigned to such Holder. The term
“Mortgage” whenever used in this Lease shall be deemed to include deeds of trust, security assignments and any other encumbrances, and any reference to the “Holder” of a Mortgage shall be deemed to include the
beneficiary under a deed of trust. 
 28. Surrender. Upon the expiration of the Term or earlier termination of Tenant’s right of
possession, Tenant shall surrender the Premises to Landlord in the same condition as received, subject to any Alterations or Installations permitted by Landlord to remain in the Premises, free of Hazardous Materials brought upon, kept, used, stored,
handled, treated, generated in, or released or disposed of from, the Premises by any person other than a Landlord Party (collectively, “Tenant HazMat Operations”) and released of all Hazardous Materials Clearances, broom clean,
ordinary wear and tear and casualty loss and condemnation covered by Sections 18 and 19 excepted. At least 3 months prior to the surrender of the Premises, Tenant shall deliver to Landlord a narrative description of the actions
proposed (or required by any Governmental Authority) to be taken by Tenant in order to surrender the Premises (including any Installations permitted by Landlord to remain in the Premises) at the expiration or earlier termination of the Term, free
from any residual impact from the Tenant HazMat Operations and otherwise released for unrestricted use and occupancy (the “Surrender Plan”). Such Surrender Plan shall be accompanied by a current listing of (i) all Hazardous
Materials licenses and permits held by or on behalf of any Tenant Party with respect to the Premises, and (ii) all Hazardous Materials used, stored, handled, treated, generated, released or disposed of from the Premises, and shall be subject to
the review and approval of Landlord’s environmental consultant. In connection with the review and approval of the Surrender Plan, upon the request of Landlord, Tenant shall deliver to Landlord or its consultant such additional non-proprietary information concerning Tenant HazMat Operations as Landlord shall request. On or before such surrender, Tenant shall deliver to Landlord evidence that the approved Surrender Plan shall have been
satisfactorily completed and Landlord shall have the right, subject to reimbursement at Tenant’s expense as set forth below, to cause Landlord’s environmental consultant to inspect the Premises and perform such additional procedures as may
be deemed reasonably necessary to confirm that the Premises are, as of the effective date of such surrender or early termination of the Lease, free from any residual impact from Tenant HazMat Operations. Tenant shall reimburse Landlord, as
Additional Rent, for the actual out-of pocket expense incurred by Landlord for Landlord’s environmental consultant to review and approve the Surrender Plan and to visit the Premises and verify
satisfactory completion of the same, which cost shall not exceed $2.500. Landlord shall have the unrestricted right to deliver such Surrender Plan and any report by Landlord’s environmental consultant with respect to the surrender of the
Premises to third parties. 
 If Tenant shall fail to prepare or submit a Surrender Plan approved by Landlord, or if Tenant shall fail to
complete the approved Surrender Plan, or if such Surrender Plan, whether or not approved by Landlord, shall fail to adequately address any residual effect of Tenant HazMat Operations in, on or about the Premises, Landlord shall have the right to
take such actions as Landlord may deem reasonable or 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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appropriate to assure that the Premises and the Project are surrendered free from any residual impact from Tenant HazMat Operations, the cost of which actions shall be reimbursed by Tenant as
Additional Rent, without regard to the limitation set forth in the first paragraph of this Section 28. 
 Tenant shall
immediately return to Landlord all keys and/or access cards to parking, the Project, restrooms or all or any portion of the Premises furnished to or otherwise procured by Tenant. If any such access card or key is lost, Tenant shall pay to Landlord,
at Landlord’s election, either the reasonable cost of replacing such lost access card or key or the reasonable cost of reprogramming the access security system in which such access card was used or changing the lock or locks opened by such lost
key. Any Tenant’s Property, Alterations and property not so removed by Tenant as permitted or required herein shall be deemed abandoned and may be stored, removed, and disposed of by Landlord at Tenant’s expense, and Tenant waives all
claims against Landlord for any damages resulting from Landlord’s retention and/or disposition of such property. All obligations of Tenant hereunder not fully performed as of the termination of the Term, including the obligations of Tenant
under Section 30 hereof, shall survive the expiration or earlier termination of the Term, including, without limitation, indemnity obligations, payment obligations with respect to Rent and obligations concerning the condition and repair
of the Premises. 
 29. Waiver of Jury Trial. TO THE EXTENT PERMITTED BY LAW, TENANT AND LANDLORD WAIVE ANY RIGHT TO TRIAL BY JURY OR
TO HAVE A JURY PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT, OR OTHERWISE, BETWEEN LANDLORD AND TENANT ARISING OUT OF THIS LEASE OR ANY OTHER INSTRUMENT, DOCUMENT, OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH
OR THE TRANSACTIONS RELATED HERETO. 
 30. Environmental Requirements.  

(a) Prohibition/Compliance/Indemnity. Tenant shall not cause or permit any Hazardous Materials (as hereinafter defined) to be brought
upon, kept, used, stored, handled, treated, generated in or about, or released or disposed of from, the Premises or the Project in violation of applicable Environmental Requirements (as hereinafter defined) by Tenant or any Tenant Party. If Tenant
breaches the obligation stated in the preceding sentence, or if the presence of Hazardous Materials in the Premises during the Term or any holding over results in contamination of the Premises, the Project or any adjacent property or if
contamination of the Premises, the Project or any adjacent property by Hazardous Materials brought into, kept, used, stored, handled, treated, generated in or about, or released or disposed of from, the Premises by anyone other than Landlord and
Landlord’s employees, agents and contractors otherwise occurs during the Term or any holding over, Tenant hereby indemnifies and shall defend and hold Landlord, its officers, directors, employees, agents and contractors harmless from any and
all actions (including, without limitation, remedial or enforcement actions of any kind, administrative or judicial proceedings, and orders or judgments arising out of or resulting therefrom), costs, claims, damages (including, without limitation,
punitive damages and damages based upon diminution in value of the Premises or the Project, or the loss of, or restriction on, use of the Premises or any portion of the Project), expenses (including, without limitation, attorneys’,
consultants’ and experts’ fees, court costs and amounts paid in settlement of any claims or actions), fines, forfeitures or other civil, administrative or criminal penalties, injunctive or other relief (whether or not based upon personal
injury, property damage, or contamination of, or adverse effects upon, the environment, water tables or natural resources), liabilities or losses (collectively, “Environmental Claims”) which arise during or after the Term as a
result of such contamination. This indemnification of Landlord by Tenant includes, without limitation, costs incurred in connection with any investigation of site conditions or any cleanup, treatment, remedial, removal, or restoration work required
by any federal, state or local Governmental Authority because of Hazardous Materials present in the air, soil or ground water above, on, or under the Premises. Without limiting the foregoing, if the presence of any Hazardous Materials on the
Premises, , the Building, the Project or any adjacent property caused or permitted by Tenant or any Tenant Party results in any contamination of the Premises, the Building, the Project or any adjacent property, Tenant shall promptly take all actions
at its sole expense and in accordance with applicable Environmental Requirements as are necessary to return the Premises, the Building, the Project or any adjacent property to the condition 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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existing prior to the time of such contamination, provided that Landlord’s approval of such action shall first be obtained, which approval shall not unreasonably be withheld so long as such
actions would not potentially have any material adverse long-term or short-term effect on the Premises, the Building or the Project. Notwithstanding anything to the contrary contained in this Section 30, Tenant shall not be responsible
for, and the indemnification and hold harmless obligation set forth in this paragraph shall not apply to (i) contamination in the Premises which Tenant can prove existed in the Premises immediately prior to the Commencement Date, or
(ii) the presence of any Hazardous Materials in the Premises which Tenant can prove migrated from outside of the Premises into the Premises, unless in either case, the presence of such Hazardous Materials (x) is the result of a breach by
Tenant of any of its obligations under this Lease, or (y) was caused, contributed to or exacerbated by Tenant or any Tenant Party. 

(b) Business. Landlord acknowledges that it is not the intent of this Section 30 to prohibit Tenant from using the Premises
for the Permitted Use. Tenant may operate its business according to prudent industry practices so long as the use or presence of Hazardous Materials is strictly and properly monitored according to all then applicable Environmental Requirements. As a
material inducement to Landlord to allow Tenant to use Hazardous Materials in connection with its business, Tenant agrees to deliver to Landlord prior to the Commencement Date a list identifying each type of Hazardous Materials to be brought upon,
kept, used, stored, handled, treated, generated on, or released or disposed of from, the Premises and setting forth any and all governmental approvals or permits required in connection with the presence, use, storage, handling, treatment,
generation, release or disposal of such Hazardous Materials on or from the Premises (“Hazardous Materials List”). Tenant shall deliver to Landlord an updated Hazardous Materials List at least once a year and shall also deliver an
updated list before any new Hazardous Material is brought onto, kept, used, stored, handled, treated, generated on, or released or disposed of from, the Premises. Tenant shall deliver to Landlord true and correct copies of the following documents
(the “Haz Mat Documents”) relating to the use, storage, handling, treatment, generation, release or disposal of Hazardous Materials prior to the Commencement Date, or if unavailable at that time, concurrent with the receipt from or
submission to a Governmental Authority: permits; approvals; reports and correspondence; storage and management plans, notice of violations of any Legal Requirements; plans relating to the installation of any storage tanks to be installed in or under
the Project (provided, said installation of tanks shall only be permitted after Landlord has given Tenant its written consent to do so, which consent may be withheld in Landlord’s sole and absolute discretion); all closure plans or any other
documents required by any and all federal, state and local Governmental Authorities for any storage tanks installed in, on or under the Project for the closure of any such tanks; and a Surrender Plan (to the extent surrender in accordance with
Section 28 cannot be accomplished in 3 months). Tenant is not required, however, to provide Landlord with any portion(s) of the Haz Mat Documents containing information of a proprietary nature which, in and of themselves, do not contain
a reference to any Hazardous Materials or hazardous activities. It is not the intent of this Section to provide Landlord with information which could be detrimental to Tenant’s business should such information become possessed by Tenant’s
competitors. 
 (c) Tenant Representation and Warranty. Tenant hereby represents and warrants to Landlord that (i) neither
Tenant nor any of its legal predecessors has been required by any prior landlord, lender or Governmental Authority at any time to take remedial action in connection with Hazardous Materials contaminating a property which contamination was permitted
by Tenant of such predecessor or resulted from Tenant’s or such predecessor’s action or use of the property in question, and (ii) Tenant is not subject to any enforcement order issued by any Governmental Authority in connection with
the use, storage, handling, treatment, generation, release or disposal of Hazardous Materials (including, without limitation, any order related to the failure to make a required reporting to any Governmental Authority). If Landlord determines that
this representation and warranty was not true as of the date of this lease, Landlord shall have the right to terminate this Lease in Landlord’s sole and absolute discretion. 

(d) Testing. Landlord shall have the right to conduct annual tests of the Premises to determine whether any contamination of the
Premises or the Project has occurred as a result of Tenant’s use. Tenant shall be required to pay the cost of such annual test of the Premises if there is violation of this Section 30 or if contamination for which Tenant is
responsible under this Section 30 is identified; provided, however, that if Tenant conducts its own tests of the Premises using third party contractors and 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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test procedures reasonably acceptable to Landlord which tests are certified to Landlord, Landlord shall accept such tests in lieu of the annual tests to be paid for by Tenant. In addition, at any
time, and from time to time, prior to the expiration or earlier termination of the Term, Landlord shall have the right to conduct appropriate tests of the Premises and the Project to determine if contamination has occurred as a result of
Tenant’s use of the Premises. In connection with such testing under this Section 30(d), upon the request of Landlord, Tenant shall deliver to Landlord or its consultant such non-proprietary
information concerning the use of Hazardous Materials in or about the Premises by Tenant or any Tenant Party. If contamination has occurred for which Tenant is liable under this Section 30, Tenant shall pay all costs to conduct such
tests. If no such contamination is found, Landlord shall pay the costs of such tests (which shall not constitute an Operating Expense). Landlord shall provide Tenant with a copy of all third party,
non-confidential reports and tests of the Premises made by or on behalf of Landlord during the Term without representation or warranty and subject to a confidentiality agreement. Tenant shall, at its sole cost
and expense, promptly and satisfactorily remediate any environmental conditions identified by such testing in accordance with all Environmental Requirements. Landlord’s receipt of or satisfaction with any environmental assessment in no way
waives any rights which Landlord may have against Tenant. 
 (e) Control Areas. Tenant shall be allowed to utilize up to its pro rata
share of the Hazardous Materials inventory within any control area or zone (located within the Premises), as designated by the applicable building code, for chemical use or storage. As used in the preceding sentence, Tenant’s pro rata share of
any control areas or zones located within the Premises shall be determined based on the rentable square footage that Tenant leases within the applicable control area or zone. For purposes of example only, if a control area or zone contains 10,000
rentable square feet and 2,000 rentable square feet of a tenant’s premises are located within such control area or zone (while such premises as a whole contains 5,000 rentable square feet), the applicable tenant’s pro rata share of such
control area would be 20%. 
 (f) Underground Tanks. Tenant shall have no right to use or install any underground or other storage
tanks at the Project. 
 (g) Tenant’s Obligations. Tenant’s obligations under this Section 30 shall survive the
expiration or earlier termination of the Lease. During any period of time after the expiration or earlier termination of this Lease required by Tenant or Landlord to complete the removal from the Premises of any Hazardous Materials (including,
without limitation, the release and termination of any licenses or permits restricting the use of the Premises and the completion of the approved Surrender Plan), Tenant shall continue to pay the full Rent in accordance with this Lease for any
portion of the Premises not relet by Landlord in Landlord’s sole discretion, which Rent shall be prorated daily. 
 (h) Definitions.
As used herein, the term “Environmental Requirements” means all applicable present and future statutes, regulations, ordinances, rules, codes, judgments, orders or other similar enactments of any Governmental Authority
regulating or relating to health, safety, or environmental conditions on, under, or about the Premises or the Project, or the environment, including without limitation, the following: the Comprehensive Environmental Response, Compensation and
Liability Act; the Resource Conservation and Recovery Act; and all state and local counterparts thereto, and any regulations or policies promulgated or issued thereunder. As used herein, the term “Hazardous Materials” means and
includes any substance, material, waste, pollutant, or contaminant listed or defined as hazardous or toxic, or regulated by reason of its impact or potential impact on humans, animals and/or the environment under any Environmental Requirements,
asbestos and petroleum, including crude oil or any fraction thereof, natural gas liquids, liquefied natural gas, or synthetic gas usable for fuel (or mixtures of natural gas and such synthetic gas). As defined in Environmental Requirements, Tenant
is and shall be deemed to be the “operator” of Tenant’s “facility” and the “owner” of all Hazardous Materials brought on the Premises by Tenant or any Tenant Party, and the wastes, by-products, or residues generated, resulting, or produced therefrom. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 31. Tenant’s Remedies/Limitation of Liability. Landlord shall not be in default
hereunder unless Landlord fails to perform any of its obligations hereunder within 30 days after written notice from Tenant specifying such failure (unless such performance will, due to the nature of the obligation, require a period of time in
excess of 30 days, then, so long as Landlord continues to use reasonable efforts to perform, after such period of time as is reasonably necessary). Upon any default by Landlord, Tenant shall give notice by registered or certified mail to any Holder
of a Mortgage covering the Premises and to any landlord of any lease of property in or on which the Premises are located and Tenant shall offer such Holder and/or landlord a reasonable opportunity to cure the default, including time to obtain
possession of the Project by power of sale or a judicial action if such should prove necessary to effect a cure; provided Landlord shall have furnished to Tenant in writing the names and addresses of all such persons who are to receive such
notices. All obligations of Landlord hereunder shall be construed as covenants, not conditions; and, except as may be otherwise expressly provided in this Lease, Tenant may not terminate this Lease for breach of Landlord’s obligations
hereunder. 
 All obligations of Landlord under this Lease will be binding upon Landlord only during the period of its ownership of the
Premises and not thereafter. The term “Landlord” in this Lease shall mean only the owner for the time being of the Premises. Upon the transfer by such owner of its interest in the Premises, such owner shall thereupon be released and
discharged from all obligations of Landlord thereafter accruing, but such obligations shall be binding during the Term upon each new owner for the duration of such owner’s ownership. 

32. Inspection and Access. Subject to the terms and conditions of this Section 32, Landlord and its agents,
representatives, and contractors may enter the Premises at any reasonable time to inspect the Premises and to make such repairs as may be required or permitted pursuant to this Lease and for any other business purpose. Landlord and Landlord’s
representatives may enter the Premises during business hours on not less than 48 hours advance written notice (except in the case of emergencies in which case no such notice shall be required and such entry may be at any time) for the purpose of
effecting any such repairs, inspecting the Premises, showing the Premises to prospective purchasers and, during the last year of the Term, to prospective tenants or for any other business purpose. Landlord may erect a suitable sign (i) on the
Premises stating the Premises are available to let during the last 9 months of the Term and (ii) at the Project stating that the Project is available for sale. Landlord may grant easements, make public dedications, designate Common Areas and
create restrictions on or about the Premises, provided that no such easement, dedication, designation or restriction materially, adversely affects Tenant’s use or occupancy of the Premises for the Permitted Use. At Landlord’s
request, Tenant shall execute such instruments as may be necessary for such easements, dedications or restrictions. Tenant shall at all times, except in the case of emergencies, have the right to escort Landlord or its agents, representatives,
contractors or guests while the same are in the Premises, provided such escort does not materially and adversely affect Landlord’s access rights hereunder. During Landlord’s access of the Premises, Landlord shall use reasonable efforts to
comply with Tenant’s reasonable safety and security requirements; provided, however, that Tenant has notified Landlord of such safety and security requirements prior to Landlord’s entry into the Premises. 

33. Security. Tenant acknowledges and agrees that security devices and services, if any, while intended to deter crime may not in given
instances prevent theft or other criminal acts and that Landlord is not providing any security services with respect to the Premises. Tenant agrees that Landlord shall not be liable to Tenant for, and Tenant waives any claim against Landlord with
respect to, any loss by theft or any other damage suffered or incurred by Tenant in connection with any unauthorized entry into the Premises or any other breach of security with respect to the Premises. Tenant shall be solely responsible for the
personal safety of Tenant’s officers, employees, agents, contractors, guests and invitees while any such person is in, on or about the Premises and/or the Project. Tenant shall at Tenant’s cost obtain insurance coverage to the extent
Tenant desires protection against such criminal acts. 
 34. Force Majeure. Except for the payment of Rent, neither Landlord nor
Tenant shall be held responsible or liable for delays in the performance of its obligations hereunder when caused by, related to, or arising out of acts of God, sinkholes or subsidence, strikes, lockouts, or other labor disputes, embargoes,
quarantines, weather, national, regional, or local disasters, calamities, or catastrophes, inability to obtain labor or materials (or reasonable substitutes therefor) at reasonable costs or failure of,


  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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or inability to obtain, utilities necessary for performance, governmental restrictions, orders, limitations, regulations, or controls, national emergencies, delay in issuance or revocation of
permits, enemy or hostile governmental action, terrorism, insurrection, riots, civil disturbance or commotion, fire or other casualty, and other causes or events beyond their reasonable control (“Force Majeure”).  

35. Brokers. Landlord and Tenant each represents and warrants that it has not dealt with any broker, agent or other person
(collectively, “Broker”) in connection with this transaction and that no Broker brought about this transaction, other than Jones Lang LaSalle and Transwestern RBJ. Landlord and Tenant each hereby agree to indemnify and hold the
other harmless from and against any claims by any Broker, other than Jones Lang LaSalle and Transwestern RBJ, claiming a commission or other form of compensation by virtue of having dealt with Tenant or Landlord, as applicable, with regard to this
leasing transaction. Landlord shall be responsible for all commissions due to Jones Lang LaSalle and Transwestern RBJ arising out of the execution of this Lease in accordance with the terms of separate written agreement(s) between Landlord and the
brokers named in this Section 35. 
 36. Limitation on Landlord’s Liability. NOTWITHSTANDING ANYTHING SET FORTH
HEREIN OR IN ANY OTHER AGREEMENT BETWEEN LANDLORD AND TENANT TO THE CONTRARY: (A) LANDLORD SHALL NOT BE LIABLE TO TENANT OR ANY OTHER PERSON FOR (AND TENANT AND EACH SUCH OTHER PERSON ASSUME ALL RISK OF) LOSS, DAMAGE OR INJURY, WHETHER ACTUAL
OR CONSEQUENTIAL TO: TENANT’S PERSONAL PROPERTY OF EVERY KIND AND DESCRIPTION, INCLUDING, WITHOUT LIMITATION TRADE FIXTURES, EQUIPMENT, INVENTORY, SCIENTIFIC RESEARCH, SCIENTIFIC EXPERIMENTS, LABORATORY ANIMALS, PRODUCT, SPECIMENS, SAMPLES,
AND/OR SCIENTIFIC, BUSINESS, ACCOUNTING AND OTHER RECORDS OF EVERY KIND AND DESCRIPTION KEPT AT THE PREMISES AND ANY AND ALL INCOME DERIVED OR DERIVABLE THEREFROM; (B) THERE SHALL BE NO PERSONAL RECOURSE TO LANDLORD FOR ANY ACT OR OCCURRENCE
IN, ON OR ABOUT THE PREMISES OR ARISING IN ANY WAY UNDER THIS LEASE OR ANY OTHER AGREEMENT BETWEEN LANDLORD AND TENANT WITH RESPECT TO THE SUBJECT MATTER HEREOF AND ANY LIABILITY OF LANDLORD HEREUNDER SHALL BE STRICTLY LIMITED SOLELY TO
LANDLORD’S INTEREST IN THE PROJECT OR ANY PROCEEDS FROM SALE OR CONDEMNATION THEREOF AND ANY INSURANCE PROCEEDS PAYABLE IN RESPECT OF LANDLORD’S INTEREST IN THE PROJECT OR IN CONNECTION WITH ANY SUCH LOSS; AND (C) IN NO EVENT SHALL
ANY PERSONAL LIABILITY BE ASSERTED AGAINST LANDLORD IN CONNECTION WITH THIS LEASE NOR SHALL ANY RECOURSE BE HAD TO ANY OTHER PROPERTY OR ASSETS OF LANDLORD OR ANY OF LANDLORD’S OFFICERS, DIRECTORS, EMPLOYEES, AGENTS OR CONTRACTORS. UNDER NO
CIRCUMSTANCES SHALL LANDLORD OR ANY OF LANDLORD’S OFFICERS, DIRECTORS, EMPLOYEES, AGENTS OR CONTRACTORS BE LIABLE FOR INJURY TO TENANT’S BUSINESS OR FOR ANY LOSS OF INCOME OR PROFIT THEREFROM. 

37. Severability. If any clause or provision of this Lease is illegal, invalid or unenforceable under present or future laws, then and
in that event, it is the intention of the parties hereto that the remainder of this Lease shall not be affected thereby. It is also the intention of the parties to this Lease that in lieu of each clause or provision of this Lease that is illegal,
invalid or unenforceable, there be added, as a part of this Lease, a clause or provision as similar in effect to such illegal, invalid or unenforceable clause or provision as shall be legal, valid and enforceable. 

38. Signs; Exterior Appearance. Tenant shall not, without the prior written consent of Landlord, which may be granted or withheld in
Landlord’s sole discretion: (i) attach any awnings, exterior lights, decorations, balloons, flags, pennants, banners, painting or other projection to any outside wall of the Project, (ii) use any curtains, blinds, shades or screens
other than Landlord’s standard window coverings, (iii) coat or otherwise sunscreen the interior or exterior of any windows, (iv) place any bottles, parcels, or other articles on the window sills, (v) place any equipment,
furniture or other items of personal property on any exterior balcony, or (vi) paint, affix or exhibit on any part of the Premises or the Project any signs, notices, window or door lettering, placards, decorations, or advertising media of any
type which can be viewed from the exterior of the Premises. Interior signs on doors and the directory tablet shall be inscribed, painted or affixed for Tenant at Landlord’s cost, and shall be of a size, color and type reasonably acceptable to
Landlord. Nothing may be placed on the exterior of corridor walls or corridor doors other than Landlord’s standard lettering. The directory tablet shall be provided exclusively for the display of the name and location of tenants. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 Tenant shall have the exclusive right to display, at Tenant’s cost and expense, one
(1) sign bearing Tenant’s name and/or logo (each, a “Building Sign”) at one (1) location on the building facade reasonably acceptable to Landlord and Tenant. Notwithstanding the foregoing, Tenant acknowledges and
agrees that the Building Sign including, without limitation, the size, color and type, shall be subject to Landlord’s prior written approval, which shall not be unreasonably withheld, conditioned or delayed, shall be consistent with
Landlord’s signage program at the Project and shall be subject to any and all other required approvals and applicable Legal Requirements. Landlord shall cooperate with Tenant, at no cost or expense to Landlord, in Tenant’s efforts to
obtain approvals for Tenant’s Building Sign from the applicable Governmental Authorities. Tenant shall be responsible, at Tenant’s sole cost and expense, for the maintenance of the Building Sign, for the removal of the Building Sign at the
expiration or earlier termination of this Lease and for the repair of all damage resulting from such removal. The Building Sign shall be personal to Homology Medicines, Inc., except that such right may be assigned in connection with any Permitted
Assignment. 
 Tenant shall have the non-exclusive right to display, at Landlord’s cost and
expense, Tenant’s name on the monument sign at the Project serving the Building (“Monument Sign”). Tenant acknowledges and agrees that Tenant’s signage on the Monument Sign including, without limitation, the location,
size, color and type, shall be subject to Landlord’s prior written approval, which shall not be unreasonably withheld and shall be consistent with Landlord’s signage program at the Project and applicable Legal Requirements. Tenant shall be
responsible, at Tenant’s sole cost and expense, for the maintenance of Tenant’s signage on the Monument Sign, for the removal of Tenant’s signage from the Monument Sign at the expiration or earlier termination of this Lease and for
the repair of all damage resulting from such removal. Landlord agrees that the corporate logo, graphics and colors which are registered and in use by Tenant as of the date of this Lease have been approved by Landlord for use on Tenant’s signage
at the Project. 
 39. Right to Expand in Building.  

(a) Expansion in the Building. Following the first time after the date of this Lease that Landlord leases the Expansion
Space to a third party, Tenant shall thereafter during the Base Term have an ongoing right, but not the obligation, to expand the Premises (the “Expansion Right”) to include the Expansion Space upon the terms and conditions set
forth in this Section. For purposes of this Section 39(a), “Expansion Space” shall mean any space in the Building located directly adjacent to the Premises, which is not occupied by a tenant or which is occupied by a
then-existing tenant whose lease is expiring within 9 months or less and such tenant does not wish to renew (whether or not such tenant has a right to renew) its occupancy of such space. If there is any Expansion Space after the initial lease up by
Landlord of such Expansion Space to a third party, Landlord shall, at such time as Landlord shall elect so long as Tenant’s rights hereunder are preserved, deliver to Tenant written notice (the “Expansion Notice”) of such
Expansion Space, together with the terms and conditions on which Landlord is prepared to lease Tenant the Expansion Space; provided that Base Rent for the Expansion Space shall be at the Market Rate (as defined in Section 40(a) below)
and the leasing of the Expansion Space to Tenant shall incorporate market concessions and tenant improvements allowances (collectively, “Market Terms”). Tenant shall be entitled to exercise its right under this
Section 39(a) only with respect to the entire Expansion Space identified in the Expansion Notice (“Identified Expansion Space”). Tenant shall have 10 days following delivery of the Expansion Notice to deliver to Landlord
written notification of Tenant’s exercise of the Expansion Right (“Exercise Notice”) with respect to the Identified Expansion Space. Tenant shall be entitled to lease the Identified Expansion Space upon the terms and conditions
set forth in the Expansion Notice and otherwise consistent with the terms of this Lease. If Landlord and Tenant are unable to agree on the Market Terms for the Identified Expansion Space after negotiating in good faith within 5 business days after
Tenant’s delivery of an Exercise Notice, the applicable Market Terms 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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will be determined through arbitration in accordance with Section 40(b) below. If Tenant’s Expansion Right is exercised during the first 24 months of the Base Term, then the term
of the Lease with respect to the Identified Expansion Space shall be co-terminous with the Term of the Lease with respect to the then-existing Premises. If Tenant’s Expansion Right is exercised after the
expiration of the 24th month of the Base Term, then the Term of the lease with respect to the Identified Expansion Space may not be co-terminous with the
Term of the Lease with respect to the then-existing Premises. Notwithstanding anything to the contrary contain herein, in no event shall the Work Letter apply to the Identified Expansion Space. If Tenant fails to deliver an Exercise Notice to
Landlord for the Identified Expansion Space within the required 10 day period, Tenant shall be deemed to have waived its rights under this Section 39(a) to lease the Expansion Space, and Landlord shall have the right to lease the
Expansion Space to any third party on any terms and conditions acceptable to Landlord. Notwithstanding anything to the contrary contained herein, Tenant shall have no right to exercise the Expansion Right and the provisions of this
Section 39(a) shall no longer apply after the date that is 9 months prior to the expiration of the Base Term if Tenant has not exercised its Extension Right pursuant to Section 40. 

(b) Amended Lease. If: (i) Tenant fails to timely deliver an Exercise Notice, or (ii) following Tenant’s delivery of an
exercise notice to Landlord, Landlord tenders to Tenant an amendment to this Lease for the rental of the Identified Expansion Space reasonably acceptable to Landlord and Tenant, each in their reasonable discretion, and Tenant fails to execute such
Lease amendment within 10 business days following such tender, Tenant shall be deemed to have waived its right to lease the Identified Expansion Space. 

(c) Exceptions. Notwithstanding the above, the Expansion Right shall, at Landlord’s option, not be in effect and may not be
exercised by Tenant: 
 (i) during any period of time that Tenant is in Default under any provision of the Lease; or 

(ii) if Tenant has been in Default under any provision of the Lease 3 or more times, whether or not the Defaults are cured,
during the 12 month period prior to the date on which Tenant seeks to exercise the Expansion Right. 
 (d) Termination. The Expansion
Right shall, at Landlord’s option, terminate and be of no further force or effect even after Tenant’s due and timely exercise of the Expansion Right, if, after such exercise, but prior to the commencement date of the lease of the
Identified Expansion Space, (i) Tenant fails to timely cure any default by Tenant under the Lease; or (ii) Tenant has Defaulted 3 or more times during the period from the date of the exercise of the Expansion Right to the date of the
commencement of the lease of the Identified Expansion Space, whether or not such Defaults are cured. 
 (e) Rights Personal. The
Expansion Right is personal to Tenant and is not assignable without Landlord’s consent, which may be granted or withheld in Landlord’s sole discretion separate and apart from any consent by Landlord to an assignment of Tenant’s
interest in the Lease, except that they may be assigned in connection with any Permitted Assignment of this Lease. 
 (f) No Extensions.
The period of time within which the Expansion Right may be exercised shall not be extended or enlarged by reason of Tenant’s inability to exercise the Expansion Right. 

40. Right to Extend Term. Tenant shall have the right to extend the Term of the Lease upon the following terms and conditions: 

(a) Extension Rights. Tenant shall have 1 right (the “Extension Right”) to extend the term of this Lease for 3 years
(the “Extension Term”) on the same terms and conditions as this Lease (other than with respect to Base Rent and the Work Letter) by giving Landlord written notice of its election to exercise each Extension Right at least 9 months
prior to the expiration of the Base Term of the Lease. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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Upon the commencement of the Extension Term, Base Rent shall be payable at the Market Rate (as defined below). Base Rent shall thereafter be adjusted on each annual anniversary of the
commencement of such Extension Term by a percentage as agreed upon by Landlord and Tenant at the time the Market Rate is determined. As used herein, “Market Rate” shall mean the rate that comparable landlords of comparable buildings
have accepted in current transactions from non-equity (i.e., not being offered equity in the buildings) and nonaffiliated tenants of similar financial strength for space of comparable size, quality (including
Alterations and other improvements) and floor height in laboratory/office buildings in the Bedford area for a comparable term, with the determination of the Market Rate to take into account all relevant factors, including tenant inducements,
percentage of laboratory and office space, views, project amenities, parking costs, leasing commissions, allowances or concessions, if any. Notwithstanding anything to the contrary contained herein, in no event shall the Market Rate for the first
year of the Extension Term be less than the Base Rent payable as of the date immediately preceding the commencement of the Extension Term as increased by the Rent Adjustment Percentage. 

If, on or before the date which is 240 days prior to the expiration of the Base Term of this Lease, Tenant has not agreed with Landlord’s
determination of the Market Rate and the rent escalations during the Extension Term after negotiating in good faith, Tenant shall be deemed to have elected arbitration as described in Section 40(b). Tenant acknowledges and agrees that,
if Tenant has elected to exercise the Extension Right by delivering notice to Landlord as required in this Section 40(a), Tenant shall have no right thereafter to rescind or elect not to extend the term of the Lease for the Extension
Term. 
 (b) Arbitration.  

(i) Within 10 days of Tenant’s notice to Landlord of its election (or deemed election) to arbitrate Market Rate and
escalations, each party shall deliver to the other a proposal containing the Market Rate and escalations that the submitting party believes to be correct (“Extension Proposal”). If either party fails to timely submit an Extension
Proposal, the other party’s submitted proposal shall determine the Base Rent and escalations for the Extension Term. If both parties submit Extension Proposals, then Landlord and Tenant shall meet within 7 days after delivery of the last
Extension Proposal and make a good faith attempt to mutually appoint a single Arbitrator (and defined below) to determine the Market Rate and escalations. If Landlord and Tenant are unable to agree upon a single Arbitrator, then each shall, by
written notice delivered to the other within 10 days after the meeting, select an Arbitrator. If either party fails to timely give notice of its selection for an Arbitrator, the other party’s submitted proposal shall determine the Base Rent for
the Extension Term. The 2 Arbitrators so appointed shall, within 5 business days after their appointment, appoint a third Arbitrator. If the 2 Arbitrators so selected cannot agree on the selection of the third Arbitrator within the time above
specified, then either party, on behalf of both parties, may request such appointment of such third Arbitrator by application to any state court of general jurisdiction in the jurisdiction in which the Premises are located, upon 10 days prior
written notice to the other party of such intent. 
 (ii) The decision of the Arbitrator(s) shall be made within 30 days
after the appointment of a single Arbitrator or the third Arbitrator, as applicable. The decision of the single Arbitrator shall be final and binding upon the parties. The average of the two closest Arbitrators in a three Arbitrator panel shall be
final and binding upon the parties. Each party shall pay the fees and expenses of the Arbitrator appointed by or on behalf of such party and the fees and expenses of the third Arbitrator shall be borne equally by both parties. If the Market Rate and
escalations are not determined by the first day of the Extension Term, then Tenant shall pay Landlord Base Rent in an amount equal to the Base Rent in effect immediately prior to the Extension Term and increased by the Rent Adjustment Percentage
until such determination is made. After the determination of the Market Rate and escalations, the parties shall make any necessary adjustments to such payments made by Tenant. Landlord and Tenant shall then execute an amendment recognizing the
Market Rate and escalations for the Extension Term. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 (iii) An “Arbitrator” shall be any person appointed by or on
behalf of either party or appointed pursuant to the provisions hereof and: (i) shall be (A) a member of the American Institute of Real Estate Appraisers with not less than 10 years of experience in the appraisal of improved office and high
tech industrial real estate in the greater Lexington, Bedford and Waltham metropolitan area, or (B) a licensed commercial real estate broker with not less than 15 years experience representing landlords and/or tenants in the leasing of high
tech or life sciences space in the greater Lexington, Bedford and Waltham metropolitan area, (ii) devoting substantially all of their time to professional appraisal or brokerage work, as applicable, at the time of appointment and (iii) be
in all respects impartial and disinterested. Any Arbitrator who has worked in any capacity for either Landlord or Tenant in the preceding five (5) years shall be disqualified from serving as an Arbitrator under this Section 39(b).

 (c) Rights Personal. The Extension Rights is personal to Tenant and is not assignable without Landlord’s consent, which may
be granted or withheld in Landlord’s sole discretion separate and apart from any consent by Landlord to an assignment of Tenant’s interest in the Lease, except that they may be assigned in connection with any Permitted Assignment of this
Lease. 
 (d) Exceptions. Notwithstanding anything set forth above to the contrary, the Extension Right shall, at Landlord’s
option, not be in effect and Tenant may not exercise the Extension Right: 
 (i) during any period of time that Tenant is in
Default under any provision of this Lease; or 
 (ii) if Tenant has been in Default under any provision of this Lease 3 or
more times, whether or not the Defaults are cured, during the 12 month period immediately prior to the date that Tenant intends to exercise the Extension Right, whether or not the Defaults are cured. 

(e) No Extensions. The period of time within which the Extension Right may be exercised shall not be extended or enlarged by reason of
Tenant’s inability to exercise the Extension Right. 
 (f) Termination. The Extension Right shall, at Landlord’s option,
terminate and be of no further force or effect even after Tenant’s due and timely exercise of the Extension Right, if, after such exercise, but prior to the commencement date of the Extension Term, (i) Tenant fails to timely cure any
default by Tenant under this Lease; or (ii) Tenant has Defaulted 3 or more times during the period from the date of the exercise of the Extension Right to the date of the commencement of the Extension Term, whether or not such Defaults are
cured. 
 41. Intentionally Omitted.  

42. Intentionally Omitted.  

43. Roof Equipment. As long as Tenant is not in default under this Lease, Tenant shall have the right at its sole cost and expense,
subject to compliance with all Legal Requirements, to install, maintain, and remove on the top of the roof of the Building (based on Tenant’s proportionate share of the space available on the roof) one or more satellite dishes, communication
antennae, HVAC or other equipment (all of which having a diameter and height acceptable to Landlord) required to support Tenant’s operations within the Premises (collectively, the “Roof Equipment”) on the following terms and
conditions: 
 (a) Requirements. Tenant shall submit to Landlord (i) the plans and specifications for the installation of the
Roof Equipment, (ii) copies of all required governmental and quasi-governmental permits, licenses, and authorizations that Tenant will and must obtain at its own expense, with the cooperation of Landlord, if necessary for the installation and
operation of the Roof Equipment, and (iii) an insurance policy or certificate of insurance evidencing insurance coverage as required by this Lease and any other insurance as reasonably required by Landlord for the installation and operation of
the Roof 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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Equipment. Landlord shall not unreasonably withhold or delay its approval for the installation and operation of the Roof Equipment; provided, however, that Landlord may reasonably
withhold its approval if the installation or operation of the Roof Equipment (A) may damage the structural integrity of the Building, (B) may void, terminate, or invalidate any applicable roof warranty, (C) may interfere with any
service provided by Landlord or any tenant of the Building, (D) may reduce the leasable space in the Building, (E) is not properly screened from the viewing public, or (E) generate excessive noise. 

(b) No Damage to Roof. If installation of the Roof Equipment requires Tenant to make any roof cuts or perform any other roofing work,
such cuts shall only be made to the roof area of the Building located directly above the Premises and only in the manner designated in writing by Landlord; and any such installation work (including any roof cuts or other roofing work) shall be
performed by Tenant, at Tenant’s sole cost and expense by a roofing contractor designated by Landlord. If Tenant or its agents shall otherwise cause any damage to the roof during the installation, operation, and removal of the Roof Equipment
such damage shall be repaired promptly at Tenant’s expense and the roof shall be restored in the same condition it was in before the damage. Landlord shall not charge Tenant Additional Rent for the installation and use of the Roof Equipment.
If, however, Landlord’s insurance premium or Tax assessment increases as a result of the Roof Equipment, Tenant shall pay such increase as Additional Rent within ten (10) days after receipt of a reasonably detailed invoice from Landlord.
Tenant shall not be entitled to any abatement or reduction in the amount of Rent payable under this Lease if for any reason Tenant is unable to use the Roof Equipment. In no event whatsoever shall the installation, operation, maintenance, or removal
of the Roof Equipment by Tenant or its agents void, terminate, or invalidate any applicable roof warranty. 
 (c) Protection. The
installation, operation, and removal of the Roof Equipment shall be at Tenant’s sole risk. Tenant shall indemnify, defend, and hold Landlord harmless from and against any and all claims, costs, damages, liabilities and expenses (including,
·but not limited to, attorneys’ fees) of every kind and description that may arise out of or be connected in any way with Tenant’s installation, operation, or removal of the Roof Equipment. 

(d) Removal. At the expiration or earlier termination of this Lease or the discontinuance of the use of the Roof Equipment by Tenant,
Tenant shall, at its sole cost and expense, remove the Roof Equipment from the Building. Tenant shall leave the portion of the roof where the Roof Equipment was located in good order and repair, reasonable wear and tear excepted. If Tenant does not
so remove the Roof Equipment, Tenant hereby authorizes Landlord to remove and dispose of the Roof Equipment and charge Tenant as Additional Rent for all costs and expenses incurred by Landlord in such removal and disposal. Tenant agrees that
Landlord shall not be liable for any Roof Equipment or related property disposed of or removed by Landlord. 
 (e) No Interference.
The Roof Equipment shall not interfere with the proper functioning of any telecommunications equipment or devices that have been installed or will be installed by Landlord or for any other tenant or future tenant of the Building. Tenant
acknowledges that other tenant(s) may have approval rights over the installation and operation of telecommunications equipment and devices on or about the roof, and that Tenant’s right to install and operate the Roof Equipment is subject and
subordinate to the rights of such other tenants. Tenant agrees that any other tenant of the Building that currently has or in the future takes possession of any portion of the Building will be permitted to install such telecommunication equipment
that is of a type and frequency that will not cause unreasonable interference to the Roof Equipment. 
 (f) Relocation. Landlord
shall have the right, at its expense and after 60 days prior notice to Tenant, to relocate the Roof Equipment to another site on the roof of the Building as long as such site reasonably meets Tenant’s sight line and interference requirements
and does not unreasonably interfere with Tenant’s use and operation of the Roof Equipment. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 (g) Access. Landlord grants to Tenant the right of ingress and egress on a 24 hour 7
day per week basis to install, operate, and maintain the Roof Equipment. Before receiving access to the roof of the Building, Tenant shall give Landlord at least 24 hours’ advance written or oral notice, except in emergency situations, in which
case 2 hours’ advance oral notice shall be given by Tenant. Landlord shall supply Tenant with the name, telephone, and pager numbers of the contact individual(s) responsible for providing access during emergencies. 

(h) Appearance. If permissible by Legal Requirements, the Roof Equipment shall be painted the same color as the Building so as to
render the Roof Equipment virtually invisible from ground level. 
 (i) No Assignment. The right of Tenant to use and operate the
Roof Equipment shall be personal solely to Homology Medicines, Inc., and (i) other than in connection with a Permitted Assignment, no other person or entity shall have any right to use or operate the Roof Equipment, and (ii) Tenant shall
not assign, convey, or otherwise transfer to any person or entity any right, title, or interest in all or any portion of the Roof Equipment or the use and operation thereof, other than in connection with a Permitted Assignment. 

44. Miscellaneous.  
 (a)
Notices. All notices or other communications between the parties shall be in writing and shall be deemed duly given upon delivery or refusal to accept delivery by the addressee thereof if delivered in person, or upon actual receipt if
delivered by reputable overnight guaranty courier, addressed and sent to the parties at their addresses set forth above. Landlord and Tenant may from time to time by written notice to the other designate another address for receipt of future
notices. 
 (b) Joint and Several Liability. If and when included within the term “Tenant,” as used in this
instrument, there is more than one person or entity, each shall be jointly and severally liable for the obligations of Tenant. 
 (c)
Financial Information. Tenant shall furnish Landlord with true and complete copies of (i) Tenant’s most recent audited annual financial statements within 180 days of the end of each of Tenant’s fiscal years during the Term, and
(ii) Tenant’s most recent unaudited quarterly financial statements within 90 days of the end of each of Tenant’s first three fiscal quarters of each of Tenant’s fiscal years during the Term, all of which shall be treated by
Landlord as confidential information belonging to Tenant. So long as Tenant is a “public company” and its financial information is publicly available, then the foregoing delivery requirements of this Section 43(c) shall not
apply. 
 (d) Recordation. Neither this Lease nor a memorandum of lease shall be filed by or on behalf of Tenant in any public
record. Landlord may prepare and file, and upon request by Landlord Tenant will execute, a memorandum of lease. 
 (e) Interpretation.
The normal rule of construction to the effect that any ambiguities are to be resolved against the drafting party shall not be employed in the interpretation of this Lease or any exhibits or amendments hereto. Words of any gender used in this
Lease shall be held and construed to include any other gender, and words in the singular number shall be held to include the plural, unless the context otherwise requires. The captions inserted in this Lease are for convenience only and in no way
define, limit or otherwise describe the scope or intent of this Lease, or any provision hereof, or in any way affect the interpretation of this Lease. 

(f) Not Binding Until Executed. The submission by Landlord to Tenant of this Lease shall have no binding force or effect, shall not
constitute an option for the leasing of the Premises, nor confer any right or impose any obligations upon either party until execution of this Lease by both parties. 

(g) Limitations on Interest. It is expressly the intent of Landlord and Tenant at all times to comply with applicable law governing the
maximum rate or amount of any interest payable on or in connection with this Lease. If applicable law is ever judicially interpreted so as to render usurious any 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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	Net Multi-Tenant Office/Laboratory	  	45 Wiggins/Homology Medicines - Page 36

  

 
interest called for under this Lease, or contracted for, charged, taken, reserved, or received with respect to this Lease, then it is Landlord’s and Tenant’s express intent that all
excess amounts theretofore collected by Landlord be credited on the applicable obligation (or, if the obligation has been or would thereby be paid in full, refunded to Tenant), and the provisions of this Lease immediately shall be deemed reformed
and the amounts thereafter collectible hereunder reduced, without the necessity of the execution of any new document, so as to comply with the applicable law, but so as to permit the recovery of the fullest amount otherwise called for hereunder.

 (h) Choice of Law. Construction and interpretation of this Lease shall be governed by the internal laws of the state in which the
Premises are located, excluding any principles of conflicts of laws. 
 (i) Time. Time is of the essence as to the performance of
Tenant’s obligations under this Lease. 
 (j) OFAC. Tenant and all beneficial owners of Tenant are currently (a) in
compliance with and shall at all times during the Term of this Lease remain in compliance with the regulations of the Office of Foreign Assets Control (“OFAC”) of the U.S. Department of Treasury and any statute, executive order, or
regulation relating thereto (collectively, the “OFAC Rules”), (b) not listed on, and shall not during the term of this Lease be listed on, the Specially Designated Nationals and Blocked Persons List, Foreign Sanctions Evaders List,
or the Sectoral Sanctions Identification List, which are all maintained by OFAC and/or on any other similar list maintained by OFAC or other governmental authority pursuant to any authorizing statute, executive order, or regulation, and (c) not
a person or entity with whom a U.S. person is prohibited from conducting business under the OFAC Rules. 
 (k) Incorporation by
Reference. All exhibits and addenda attached hereto are hereby incorporated into this Lease and made a part hereof. If there is any conflict between such exhibits or addenda and the terms of this Lease, such exhibits or addenda shall control.

 (I) Entire Agreement. This Lease, including the exhibits attached hereto, constitutes the entire agreement between Landlord and
Tenant pertaining to the subject matter hereof and supersedes all prior and contemporaneous agreements, understandings, letters of intent, negotiations and discussions, whether oral or written, of the parties, and there are no warranties,
representations or other agreements, express or implied, made to either party by the other party in connection with the subject matter hereof except as specifically set forth herein. 

(m) No Accord and Satisfaction. No payment by Tenant or receipt by Landlord of a lesser amount than the monthly installment of Base
Rent or any Additional Rent will be other than on account of the earliest stipulated Base Rent and Additional Rent, nor will any endorsement or statement on any check or letter accompanying a check for payment of any Base Rent or Additional Rent be
an accord and satisfaction. Landlord may accept such check or payment without prejudice to Landlord’s right to recover the balance of such Rent or to pursue any other remedy provided in this Lease. 

(n) Hazardous Activities. Notwithstanding any other provision of this Lease, Landlord, for itself and its employees, agents and
contractors, reserves the right to refuse to perform any repairs or services in any portion of the Premises which, pursuant to Tenant’s routine safety guidelines, practices or custom or prudent industry practices, require any form of protective
clothing or equipment other than safety glasses. In any such case, Tenant shall contract with parties who are acceptable to Landlord, in Landlord’s reasonable discretion, for all such repairs and services, and Landlord shall, to the extent
required, equitably adjust Tenant’s Share of Operating Expenses in respect of such repairs or services to reflect that Landlord is not providing such repairs or services to Tenant. 

[Signatures on next page] 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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	Net Multi-Tenant Office/Laboratory	  	45 Wiggins/Homology Medicines - Page 37

  

 IN WITNESS WHEREOF, Landlord and Tenant have executed this Lease as of the day and year first
above written. 
  

									
	 TENANT:

	
	 HOMOLOGY MEDICINES, INC.,

	 a Delaware corporation

		
	 By:
	 	/s/Arthur Tzianabos, Ph.D.
	 Its:
	 	President & CEO
	
	 LANDLORD:

	
	 ARE-MA REGION NO. 24,
LLC,

	 a Delaware limited liability company

		
	 By:
	 	ALEXANDRIA REAL ESTATE EQUITIES, L.P.,
	 	 	a Delaware limited partnership,
	 	 	managing member
				
		 		 	By:	 	ARE-QRS CORP.,
		 		 		 	a Maryland corporation,
		 		 		 	general partner


 
									
			
		 	By:	 	 /s/ Eric S. Johnson

		 	Its:	 	 Senior Vice President

RE Legal Affairs




  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 EXHIBIT A TO LEASE 

DESCRIPTION OF PREMISES 
  





 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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		  	45 Wiggins/Homology Medicines - Page 2

  

 



 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 EXHIBIT B TO LEASE 

DESCRIPTION OF PROJECT 
  





 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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		  	45 Wiggins/Homology Medicines - Page 1

  

 EXHIBIT C TO LEASE 

WORK LETTER 
 THIS
WORK LETTER (this “Work Letter”) is incorporated into that certain Lease Agreement (the “Lease”) dated as of                 ,
2016, by and between ARE-MA REGION NO. 24, LLC, a Delaware limited liability company (“Landlord”), and HOMOLOGY MEDICINES, INC., a Delaware corporation (“Tenant”).
Any initially capitalized terms used but not defined herein shall have the meanings given them in the Lease. 
 1. General
Requirements.  
 (a) Tenant’s Authorized Representative. Tenant designates Michael Silver (“Tenant’s
Representative”) as the only person authorized to act for Tenant pursuant to this Work Letter. Landlord shall not be obligated to respond to or act upon any request, approval, inquiry or other communication (“Communication”)
from or on behalf of Tenant in connection with this Work Letter unless such Communication is in writing from Tenant’s Representative. Tenant may change Tenant’s Representative at any time upon not less than 5 business days advance
written notice to Landlord. 
 (b) Landlord’s Authorized Representative. Landlord designates Tim White and Dawn Leaman (either
such individual acting alone, “Landlord’s Representative”) as the only persons authorized to act for Landlord pursuant to this Work Letter. Tenant shall not be obligated to respond to or act upon any request, approval, inquiry
or other Communication from or on behalf of Landlord in connection with this Work Letter unless such Communication is in writing from Landlord’s Representative. Landlord may change either Landlord’s Representative at any time upon not less
than 5 business days advance written notice to Tenant. 
 (c) Architects, Consultants and Contractors. Landlord and Tenant hereby
acknowledge and agree that the architect (the “Tl Architect”) for the Tenant Improvements (as defined in Section 2(a) below), the general contractor and any subcontractors for the Tenant Improvements shall be selected by
Tenant, subject to Landlord’s approval, which approval shall not be unreasonably withheld, conditioned or delayed. Landlord hereby approves Tenant’s use of The Richmond Group as the general contractor for the Tenant Improvements. Landlord
shall be named a third party beneficiary of any contract entered into by Tenant with the Tl Architect, any consultant, any contractor or any subcontractor, and of any warranty made by any contractor or any subcontractor. 

2. Tenant Improvements.  

(a) Tenant Improvements Defined. As used herein, “Tenant Improvements” shall mean (i) all improvements to the
Premises desired by Tenant of a fixed and permanent nature, and (ii) the removal of the VCT tile throughout the Premises and the installation of replacement flooring mutually agreed upon by Landlord and Tenant, each in their reasonable
discretion (the “VCT Tile Replacement”). Other than funding the Tl Allowance (as defined below) as provided herein, Landlord shall not have any obligation whatsoever with respect to the finishing of the Premises for Tenant’s
use and occupancy. Landlord shall pay the contractor performing the VCT Tile Replacement following Tenant’s delivery to Landlord of a draw request in Landlord’s standard form, containing such certifications, conditional lien waivers,
inspection reports and other matters as Landlord customarily obtains, to the extent of Landlord’s approval thereof for payment, no later than 30 days following receipt of such draw request. 

(b) Tenant’s Space Plans. Tenant shall deliver to Landlord schematic drawings and outline specifications (the “Tl Design
Drawings”) detailing Tenant’s requirements for the Tenant Improvements within 30 days of the date hereof. Not more than 5 days thereafter, Landlord shall deliver to Tenant any reasonable written objections, questions or comments of
Landlord and the Tl Architect with regard to the Tl Design Drawings. Tenant shall cause the Tl Design Drawings to be revised to address any such reasonable written comments and shall resubmit said drawings to Landlord for approval within 5 days
thereafter. Such process shall continue until Landlord has approved the Tl Design Drawings. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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 (c) Working Drawings. Not later than 15 business days following the approval of the Tl
Design Drawings by Landlord, Tenant shall cause the Tl Architect to prepare and deliver to Landlord for review and comment construction plans, specifications and drawings for the Tenant Improvements (“Tl Construction Drawings”),
which Tl Construction Drawings shall be prepared substantially in accordance with the Tl Design Drawings. Tenant shall be solely responsible for ensuring that the Tl Construction Drawings reflect Tenant’s requirements for the Tenant
Improvements. Landlord shall deliver its written comments on the Tl Construction Drawings to Tenant not later than 10 business days after Landlord’s receipt of the same; provided, however, that Landlord may not disapprove any matter that is
consistent with the Tl Design Drawings. Tenant and the Tl Architect shall consider all such comments in good faith and shall, within 10 business days after receipt, notify Landlord how Tenant proposes to respond to such comments. Any disputes in
connection with such comments shall be resolved in accordance with Section 2(d) hereof. Provided that the design reflected in the Tl Construction Drawings is consistent with the Tl Design Drawings, Landlord shall approve the Tl Construction
Drawings submitted by Tenant. Once approved by Landlord, subject to the provisions of Section 4 below, Tenant shall not materially modify the Tl Construction Drawings except as may be reasonably required in connection with the issuance
of the Tl Permit (as defined in Section 3(a) below). 
 (d) Approval and Completion. If any dispute regarding the design of
the Tenant Improvements is not settled within 10 business days after notice of such dispute is delivered by one party to the other, Tenant may make the final decision regarding the design of the Tenant Improvements, provided (i) Tenant acts
reasonably and such final decision is either consistent with or a compromise between Landlord’s and Tenant’s positions with respect to such dispute, (ii) that all costs and expenses resulting from any such decision by Tenant shall be
payable out of the Tl Fund (as defined in Section 5(d) below), and (iii) Tenant’s decision will not affect the base Building, structural components of the Building or any Building systems (in which case Landlord shall make the final
decision). Any changes to the Tl Construction Drawings following Landlord’s and Tenant’s approval of same requested by Tenant shall be processed as provided in Section 4 hereof. 

3. Performance of the Tenant Improvements.  

(a) Commencement and Permitting of the Tenant Improvements. Tenant shall commence construction of the Tenant Improvements upon
obtaining and delivering to Landlord a building permit (the “Tl Permit”) authorizing the construction of the Tenant Improvements consistent with the Tl Construction Drawings approved by Landlord. The cost of obtaining the Tl Permit
shall be payable from the Tl Fund. Landlord shall assist Tenant in obtaining the Tl Permit. Prior to the commencement of the Tenant Improvements, Tenant shall deliver to Landlord a copy of any contract with Tenant’s contractors (including the
Tl Architect), and certificates of insurance from any contractor performing any part of the Tenant Improvement evidencing industry standard commercial general liability, automotive liability, “builder’s risk”, and workers’
compensation insurance. Tenant shall cause the general contractor to provide a certificate of insurance naming Landlord, Alexandria Real Estate Equities, Inc., and Landlord’s lender (if any) as additional insureds for the general
contractor’s liability coverages required above. 
 (b) Selection of Materials, Etc. Where more than one type of material or
structure is indicated on the Tl Construction Drawings approved by Tenant and Landlord, the option will be within Tenant’s reasonable discretion if the matter concerns the Tenant Improvements, and within Landlord’s sole and absolute
subjective discretion if the matter concerns the structural components of the Building or any Building system. 
 (c) Tenant Liability.
Tenant shall be responsible for correcting any deficiencies or defects in the Tenant Improvements. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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		  	45 Wiggins/Homology Medicines - Page 3

  

 (d) Substantial Completion. Tenant shall substantially complete or cause to be
substantially completed the Tenant Improvements in a good and workmanlike manner, in accordance with the Tl Permit subject, in each case, to Minor Variations and normal “punch list” items of a
non-material nature which do not interfere with the use of the Premises (“Substantial Completion” or “Substantially Complete”). Upon Substantial Completion of the Tenant
Improvements, Tenant shall require the Tl Architect and the general contractor to execute and deliver, for the benefit of Tenant and Landlord, a Certificate of Substantial Completion in the form of the American Institute of Architects
(“AIA”) document G704. For purposes of this Work Letter, “Minor Variations” shall mean any modifications reasonably required: (i) to comply with all applicable Legal Requirements and/or to obtain or to comply
with any required permit (including the Tl Permit); (ii) to comport with good design, engineering, and construction practices which are not material; or (iii) to make reasonable adjustments for field deviations or conditions encountered during
the construction of the Tenant Improvements. 
 4. Changes. Any changes requested by Tenant to the Tenant Improvements after the
delivery and approval by Landlord of the Tl Design Drawings, shall be requested and instituted in accordance with the provisions of this Section 4 and shall be subject to the written approval of Landlord, which approval shall not be
unreasonably withheld, conditioned or delayed. 
 (a) Tenant’s Right to Request Changes. If Tenant shall request changes
(“Changes”), Tenant shall request such Changes by notifying Landlord in writing in substantially the same form as the AIA standard change order form (a “Change Request”), which Change Request shall detail the nature
and extent of any such Change. Such Change Request must be signed by Tenant’s Representative. Landlord shall review and approve or disapprove such Change Request within 10 business days thereafter, provided that Landlord’s approval shall
not be unreasonably withheld, conditioned or delayed. 
 (b) Implementation of Changes. If Landlord approves such Change and Tenant
deposits with Landlord any Excess Tl Costs (as defined in Section 5(d) below) required in connection with such Change, Tenant may cause the approved Change to be instituted. If any Tl Permit modification or change is required as a result
of such Change, Tenant shall promptly provide Landlord with a copy of such Tl Permit modification or change. 
 5. Costs.  

(a) Budget For Tenant Improvements. Before the commencement of construction of the Tenant Improvements, Tenant shall obtain a detailed
breakdown, by trade, of the costs incurred or that will be incurred, in connection with the design and construction of the Tenant Improvements (the “Budget”), and deliver a copy of the Budget to Landlord for Landlord’s
approval, which shall not be unreasonably withheld, conditioned or delayed. The Budget shall be based upon the Tl Construction Drawings approved by Landlord. If the Budget is greater than the Tl Allowance, Tenant shall deposit with Landlord the
difference, in cash, prior to the commencement of construction of the Tenant Improvements, for disbursement by Landlord as described in Section 5(d). 

(b) Tl Allowance. Landlord shall provide to Tenant a tenant improvement allowance (collectively, the “Tl Allowance”)
as follows: 
 1. a “Tenant Improvement Allowance” in the maximum amount of $15.00 per rentable square foot in the
Premises, or $345,000 in the aggregate, which is included in the Base Rent set forth in the Lease; and 
 2. an “Additional Tenant
Improvement Allowance” in the maximum amount of $15.00 per rentable square foot in the Premises, or $345,000 in the aggregate, which shall, to the extent used, result in Additional Rent as set forth in Section 4(b) of the Lease.


  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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		  	45 Wiggins/Homology Medicines - Page 4

  

 Before commencing the Tenant Improvements, Tenant shall notify Landlord how much Additional
Tenant Improvement Allowance Tenant has elected to receive from Landlord. Such election shall be final and binding on Tenant, and may not thereafter be modified without Landlord’s consent, which may be granted or withheld in Landlord’s
sole and absolute subjective discretion The Tl Allowance shall be disbursed in accordance with this Work Letter. 
 Tenant shall have no
right to the use or benefit (including any reduction to Base Rent) of any portion of the Tl Allowance not required for the construction of (i) the Tenant Improvements described in the Tl Construction Drawings approved pursuant to
Section 2(d) or (ii) any Changes pursuant to Section 4; provided, however, that to the extent that any portion of the Tl Allowance remains unused following the completion of the Tenant Improvements and payment in full of
all Tl Costs, Tenant may use such unused portion of the Tl Allowance to pay for the cost of Alterations performed by Tenant under Section 12 of the Lease within 12 months after the Commencement Date. Tenant shall have no right to any
portion of the Tl Allowance that is not disbursed before the last day of the month that is 12 months after the Commencement Date. 
 In
addition to the Tl Allowance, Landlord shall reimburse Tenant for the reasonable costs of the VCT Tile Replacement. 
 (c) Costs
lncludable in Tl Fund. The Tl Fund shall be used solely for the payment of design, permits and construction costs in connection with the construction of the Tenant Improvements, including, without limitation, the cost of electrical power and
other utilities used in connection with the construction of the Tenant Improvements, the cost of preparing the Tl Design Drawings and the Tl Construction Drawings, all costs set forth in the Budget, including the cost of Changes (collectively,
“Tl Costs”). Notwithstanding anything to the contrary contained herein, the Tl Fund shall not be used to purchase any furniture, personal property or other non-Building system materials or
equipment, including, but not be limited to, non-ducted biological safety cabinets and other scientific equipment not incorporated into the Tenant Improvements; provided, however, that a portion of the Tl Fund
may be used for Tenant’s voice and data cabling. 
 (d) Excess Tl Costs. Landlord shall have no obligation to bear any portion
of the cost of any of the Tenant Improvements except to the extent of the Tl Allowance. If at any time and from time-to-time, the remaining Tl Costs under the Budget
exceed the remaining unexpended Tl Allowance, Tenant shall deposit with Landlord, as a condition precedent to Landlord’s obligation to fund the Tl Allowance, 100% of the then current Tl Cost in excess of the remaining Tl Allowance
(“Excess Tl Costs”). If Tenant fails to deposit, or is late in depositing any Excess Tl Costs with Landlord, Landlord shall have all of the rights and remedies set forth in the Lease for nonpayment of Rent (including, but not
limited to, the right to interest at the Default Rate and the right to assess a late charge). For purposes of any litigation instituted with regard to such amounts, those amounts will be deemed Rent under the Lease. The Tl Allowance and Excess Tl
Costs is herein referred to as the “Tl Fund.” Funds deposited by Tenant shall be the first thereafter disbursed to pay Tl Costs. Notwithstanding anything to the contrary set forth in this Section 5(d), Tenant shall be
fully and solely liable for Tl Costs and the cost of Minor Variations in excess of the Tl Allowance. If upon Substantial Completion of the Tenant Improvements and the payment of all sums due in connection therewith there remains any undisbursed
portion of the Tl Fund, Tenant shall be entitled to such undisbursed Tl Fund solely to the extent of any Excess Tl Costs deposit Tenant has actually made with Landlord. 

(e) Payment for Tl Costs. During the course of design and construction of the Tenant Improvements, Landlord shall reimburse Tenant for
Tl Costs once a month against a draw request in Landlord’s standard form, containing evidence of payment of such Tl Costs by Tenant and such certifications, lien waivers (including a conditional lien release for each progress payment and
unconditional lien releases for the prior month’s progress payments), inspection reports and other matters as Landlord customarily obtains, to the extent of Landlord’s approval thereof for payment, no later than 30 days following receipt
of such draw request. Upon completion of the Tenant Improvements (and prior to any final disbursement of the Tl Fund), Tenant shall deliver to Landlord: (i) sworn statements setting forth the names of all contractors and first tier
subcontractors who did the work and final, unconditional lien waivers from all such contractors and first tier subcontractors; (ii) as-built plans (one copy in print format


  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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		  	45 Wiggins/Homology Medicines - Page 5

  

 
and two copies in electronic CAD format) for such Tenant Improvements; (iii) a certification of substantial completion in Form AIA G704, (iv) a certificate of occupancy for the Premises; and
(v) copies of all operation and maintenance manuals and warranties affecting the Premises. 
 6. Miscellaneous.  

(a) Consents. Whenever consent or approval of either party is required under this Work Letter, that party shall not unreasonably
withhold, condition or delay such consent or approval, except as may be expressly set forth herein to the contrary. 
 (b) Modification.
No modification, waiver or amendment of this Work Letter or of any of its conditions or provisions shall be binding upon Landlord or Tenant unless in writing signed by Landlord and Tenant. 

(c) No Default Funding. In no event shall Landlord have any obligation to fund any portion of the Tl Allowance during any period that
Tenant is in Default under the Lease. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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		  	45 Wiggins/Homology Medicines - Page 1

  

 EXHIBIT D TO LEASE 

ACKNOWLEDGMENT OF COMMENCEMENT DATE 

This ACKNOWLEDGMENT OF COMMENCEMENT DATE is made this          day of
                ,         , between ARE-MA REGION NO. 24, LLC, a
Delaware limited liability company (“Landlord”), and HOMOLOGY MEDICINES, INC., a Delaware corporation (“Tenant”), and is attached to and made a part of the Lease dated
                ,          (the “Lease”), by and between Landlord and Tenant. Any initially
capitalized terms used but not defined herein shall have the meanings given them in the Lease. 
 Landlord and Tenant hereby acknowledge and
agree, for all purposes of the Lease, that the Commencement Date of the Base Term of the Lease is                 ,
        , the Rent Commencement Date is                 ,         ,
and the termination date of the Base Term of the Lease shall be midnight on                 ,         . In case of
a conflict between the terms of the Lease and the terms of this Acknowledgment of Commencement Date, this Acknowledgment of Commencement Date shall control for all purposes. 

IN WITNESS WHEREOF, Landlord and Tenant have executed this ACKNOWLEDGMENT OF COMMENCEMENT DATE to be effective on the date first above
written. 
  

							
	TENANT:
	
	HOMOLOGY MEDICINES, INC.,
	 a Delaware corporation

		
	By:	 	 
	Its:	 	 
	
	LANDLORD:
	
	ARE-MA REGION NO. 24, LLC,
	a Delaware limited liability company
		
	By:	 	ALEXANDRIA REAL ESTATE EQUITIES, L.P.,
	 	 	a Delaware limited partnership,
	 	 	managing member
			
	 	 	By:	 	ARE-QRS CORP.,
	 	 	 	 	a Maryland corporation,
	 	 	 	 	general partner


 
							
			
		 		 	By:                                   
                  
		 		 	Its:                                   
                  



  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
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	Rules and Regulations	  	45 Wiggins/Homology Medicines - Page 1

  

 EXHIBIT E TO LEASE 

Rules and Regulations 

1. The sidewalk, entries, and driveways of the Project shall not be obstructed by Tenant, or any Tenant Party, or used by them for any purpose
other than ingress and egress to and from the Premises. 
 2. Tenant shall not place any objects, including antennas, outdoor furniture,
etc., in the parking areas, landscaped areas or other areas outside of its Premises, or on the roof of the Project. 
 3. Except for animals
assisting the disabled, no animals shall be allowed in the offices, halls, or corridors in the Project. 
 4. Tenant shall not disturb the
occupants of the Project or adjoining buildings by the use of any radio or musical instrument or by the making of loud or improper noises. 

5. If Tenant desires telegraphic, telephonic or other electric connections in the Premises, Landlord or its agent will direct the electrician
as to where and how the wires may be introduced; and, without such direction, no boring or cutting of wires will be permitted. Any such installation or connection shall be made at Tenant’s expense. 

6. Tenant shall not install or operate any steam or gas engine or boiler, or other mechanical apparatus in the Premises, except as
specifically approved in the Lease. The use of oil, gas or inflammable liquids for heating, lighting or any other purpose is expressly prohibited. Explosives or other articles deemed extra hazardous shall not be brought into the Project. 

7. Parking any type of recreational vehicles is specifically prohibited on or about the Project. Except for the overnight parking of operative
vehicles, no vehicle of any type shall be stored in the parking areas at any time. In the event that a vehicle is disabled, it shall be removed within 48 hours. There shall be no “For Sale” or other advertising signs on or about any parked
vehicle. All vehicles shall be parked in the designated parking areas in conformity with all signs and other markings. All parking will be open parking, and no reserved parking, numbering or lettering of individual spaces will be permitted except as
specified by Landlord. 
 8. Tenant shall use commercially reasonable efforts to maintain the Premises free from rodents, insects and other
pests. 
 9. Landlord reserves the right to exclude or expel from the Project any person who, in the judgment of Landlord, is intoxicated or
under the influence of liquor or drugs or who shall in any manner do any act in violation of the Rules and Regulations of the Project. 

10. Tenant shall not cause any unnecessary labor by reason of Tenant’s carelessness or indifference in the preservation of good order and
cleanliness. Landlord shall not be responsible to Tenant for any loss of property on the Premises, however occurring, or for any damage done to the effects of Tenant by the janitors or any other employee or person. 

11. Tenant shall give Landlord prompt notice of any defects in the water, lawn sprinkler, sewage, gas pipes, electrical lights and fixtures,
heating apparatus, or any other service equipment affecting the Premises. 
 12. Tenant shall not permit storage outside the Premises,
including without limitation, outside storage of trucks and other vehicles, or dumping of waste or refuse or permit any harmful materials to be placed in any drainage system or sanitary system in or about the Premises. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
	Copyright © 2005, Alexandria Real Estate Equities, Inc. ALL 

RIGHTS RESERVED. Confidential and Proprietary – Do Not

Copy or Distribute. Alexandria and the Alexandria Logo are   

registered trademarks of Alexandria Real Estate Equities, Inc.
	 
  

 
  












			
	Rules and Regulations	  	45 Wiggins/Homology Medicines - Page 2

  

 13. All moveable trash receptacles provided by the trash disposal firm for the Premises must
be kept in the trash enclosure areas, if any, provided for that purpose. 
 14. No auction, public or private, will be permitted on the
Premises or the Project. 
 15. No awnings shall be placed over the windows in the Premises except with the prior written consent of
Landlord. 
 16. The Premises shall not be used for lodging, sleeping or cooking (except that Tenant may use microwave ovens, toasters and
coffee makers in the Premises for the benefit of Tenant’s employees and contractors in an area designated for such items, but only if the use thereof is at all times supervised by the individual using the same) or for any immoral or illegal
purposes or for any purpose other than that specified in the Lease. No gaming devices shall be operated in the Premises. 
 17. Tenant shall
ascertain from Landlord the maximum amount of electrical current which can safely be used in the Premises, taking into account the capacity of the electrical wiring in the Project and the Premises and the needs of other tenants, and shall not use
more than such safe capacity. Landlord’s consent to the installation of electric equipment shall not relieve Tenant from the obligation not to use more electricity than such safe capacity. 

18. Tenant assumes full responsibility for protecting the Premises from theft, robbery and pilferage. 

19. Tenant shall not install or operate on the Premises any machinery or mechanical devices of a nature not directly related to Tenant’s
ordinary use of the Premises and shall keep all such machinery free of vibration, noise and air waves which may be transmitted beyond the Premises. 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
	Copyright © 2005, Alexandria Real Estate Equities, Inc. ALL 

RIGHTS RESERVED. Confidential and Proprietary – Do Not

Copy or Distribute. Alexandria and the Alexandria Logo are   

registered trademarks of Alexandria Real Estate Equities, Inc.
	 
  

 
  












			
		  	45 Wiggins/Homology Medicines - Page 1

  

 EXHIBIT F TO LEASE 

TENANT’S PERSONAL PROPERTY 

Production Basics lab tables 
 15 - 72” x 30” 

3 – 48” x 30” 
 1 – 60”x 30” 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
	Copyright © 2005, Alexandria Real Estate Equities, Inc. ALL 

RIGHTS RESERVED. Confidential and Proprietary – Do Not

Copy or Distribute. Alexandria and the Alexandria Logo are   

registered trademarks of Alexandria Real Estate Equities, Inc.
	 
  

 
  












			
		  	45 Wiggins/Homology Medicines - Page 1

  

 EXHIBIT G TO LEASE 

INTENTIONALLY OMITTED 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
	Copyright © 2005, Alexandria Real Estate Equities, Inc. ALL 

RIGHTS RESERVED. Confidential and Proprietary – Do Not

Copy or Distribute. Alexandria and the Alexandria Logo are   

registered trademarks of Alexandria Real Estate Equities, Inc.
	 
  

 
  












			
		  	45 Wiggins/Homology Medicines - Page 1

  

 EXHIBIT H TO LEASE 

LANDLORD’S FURNITURE 
 Chairs 64
(combined office, conf room and café) 
 Desks 62 (combined private offices, shipping area, open office work stations) 

Reception desk 1 
 Conference room tables 3 

Café tables 2 
 Small round tables 4 

Filing cabinets 14 
 Bookshelves 17 

  

											
		 		  	  
  
	  
 




	  
  
	  	 
 


 
	Copyright © 2005, Alexandria Real Estate Equities, Inc. ALL 

RIGHTS RESERVED. Confidential and Proprietary – Do Not

Copy or Distribute. Alexandria and the Alexandria Logo are   

registered trademarks of Alexandria Real Estate Equities, Inc.
	 
  

 
  










 Exhibit C 

Participation Rights Agreement 
 See
attached. 







 ALEXANDRIA 

Alexandria Equities, LLC 

385 E. Colorado Boulevard 

Suite 299 
 Pasadena,
California 91101 
 August     , 2016 

Homology Medicines, Inc. 
 Attention: Chief Executive Officer 

Re:     45 Wiggins Avenue, Bedford, MA 

Ladies and Gentlemen: 
 Reference is made to the
Letter of Intent, dated July 13, 2016 (“Letter of Intent”), entered into between ARE-MA Region No. 24, LLC, a Delaware limited liability company (“Landlord”), and
Homology Medicines, Inc., a Delaware corporation (“Tenant”), relating to the lease of premises at the above-referenced address (the “Lease”). Pursuant to the Letter of Intent, Landlord, or a nominee of Landlord, is
to be granted certain rights with respect to Tenant’s next round of equity financing following the date hereof. Landlord hereby designates Alexandria Equities, LLC (“Alexandria”) as its nominee under the Letter of Intent with
respect to the foregoing rights. This letter agreement (this “Participation Rights Agreement”) is intended to implement the foregoing provisions of the Letter of Intent and to replace and/or supersede any prior participation rights
agreement entered into by and between Alexandria and/or Landlord on the one hand and Tenant on the other hand. 
 1. Participation in
Future Financing. In exchange for good and valuable consideration, the receipt and sufficiency of which Tenant hereby acknowledges, Tenant hereby grants Alexandria the right, but not the obligation, to purchase any amount up to a maximum of
$2,000,000 of New Securities (as defined below) that Tenant offers to sell in its next bona fide private equity financing round following the date of this Participation Rights Agreement (the “Qualified Financing”) at a price per
share and on other terms and conditions that are no less favorable to Alexandria than those upon which the New Securities are sold by Tenant to any other investor in such Qualified Financing; provided that Alexandria is an “accredited
investor’’ at the time of the Qualified Financing. “New Securities” means any shares of Tenant’s equity securities, whether or not currently authorized, as well as rights, options, or warrants to purchase such equity
securities, or securities of any type whatsoever that are, or may become, convertible or exchangeable into or exercisable for such equity securities, but shall not include (i) any Exempted Securities, as such term is defined in Tenant’s
certificate of incorporation as in effect from time to time, (ii) any shares issued in the IPO (as defined below) or (iii) any shares issued pursuant to that certain Series A Preferred Stock Purchase Agreement among Tenant and the
Purchasers party thereto dated December 22, 2015 (including, without limitation, the Milestone Closing Shares, as defined therein). 

Tenant shall offer to sell the New Securities to Alexandria by sending written notice of such offer to investments@are.com (a “New
Securities Notice”). Any New Securities Notice shall describe the provisions of the New Securities in reasonable detail and shall specify the terms and conditions upon which they shall be sold by Tenant. Alexandria may purchase the
applicable amount of New Securities by sending written notice to Tenant of Alexandria’s election to purchase, specifying the amount of such purchase, within 20 days after receipt of the New 







 
Securities Notice, provided that Alexandria agrees (i) to execute and deliver all necessary documents in connection with such Qualified Financing reasonably requested of Alexandria,
including a definitive purchase agreement, voting agreement and such other financing agreements as shall be agreed upon by Tenant and the other investors participating in such Qualified Financing and (ii) if applicable, to tranche its
investment in the same proportion as the other investors in such Qualified Financing. Any New Securities not purchased by Alexandria may thereafter be offered for sale and sold by Tenant, on terms and conditions that are no less favorable to Tenant
than those specified in the New Securities Notice, at any time within 120 days after the expiration of Alexandria’s 20 day response period. Tenant hereby covenants that it will not enter into any agreement that conflicts with this Participation
Rights Agreement. Alexandria hereby acknowledges and agrees that the participation rights granted to certain of Tenant’s existing stockholders pursuant to that certain Investors’ Rights Agreement between Tenant and the Investors party
thereto dated November 22, 2015 (as may be amended or amended and restated from time to time) do not conflict with this Participation Rights Agreement. 

2. No Conflicts: Further Assurances. Neither the execution and delivery of this Participation Rights Agreement, nor performance of its
terms, will directly or indirectly contravene, conflict with or result in a violation of (i) any of the provisions of Tenant’s articles or certificate of incorporation or bylaws, (ii) any resolution adopted by Tenant’s
stockholders, Tenant’s board of directors or any committee thereof, or (iii) any contract or agreement of the Tenant. Tenant agrees to execute and deliver, by the proper exercise of its corporate, limited liability company, partnership or
other powers, all such other and additional instruments and documents and do all such other acts and things as may be necessary to more fully effectuate this Participation Rights Agreement and its obligations hereunder. Tenant shall use its
commercially reasonable efforts to fully effectuate the intent of this Agreement and shall not intentionally take any action to circumvent or avoid its obligations hereunder. 

3. Termination. This Participation Rights Agreement shall terminate, and be of no further force or effect, upon the earlier to occur of
the following: (i) the final closing of the Qualified Financing, whether or not Alexandria elects to purchase New Securities, but only if Tenant delivers a New Securities Notice to Alexandria and Alexandria has an opportunity to purchase the
New Securities, each as set forth in Section 1 above; (ii) immediately prior to the closing date of a transaction that qualifies as a Sale of Tenant (as defined below); (iii) immediately prior to the effective date of Tenant’s first
underwritten public offering of its securities under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (the “IPO”); and (iv) when Tenant first becomes subject to the periodic reporting
requirements of Section 12(g) or 15(d) of the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder. A “Sale of Tenant” shall mean either: (a) a transaction or series of related
transactions in which shares representing more than fifty percent of the outstanding voting power of Tenant are acquired; or (b) a transaction that qualifies as a Deemed Liquidation Event, as defined in Tenant’s then effective certificate
of incorporation. 
 4. Governing Law. The terms and conditions of this Participation Rights Agreement shall be governed by and
construed in accordance with Delaware law, without regard to the conflict of laws provisions thereof. 
 5. Successors and Assigns.
The terms and provisions of this Participation Rights Agreement shall be binding upon Alexandria, Landlord and Tenant and their respective successors and assigns, subject at all times to the restrictions set forth herein. Alexandria may not assign
this Participation Rights Agreement or any of its rights or obligations hereunder without the prior written consent of Tenant. 







 6. Confidentiality. Tenant agrees that, except with the prior written consent of
Alexandria, it shall at all times keep confidential the terms of this Participation Rights Agreement and the discussions or negotiations relating to this Participation Rights Agreement; provided that Tenant may disclose the terms of this
Participation Rights Agreement to its attorneys, accountants and other professional advisors, stockholders, and existing or prospective investors. In addition, Tenant hereby agrees that, except with the prior written consent of Alexandria, it shall
not participate in or generate any press release or other release of information to the general public relating to this Participation Rights Agreement or any transactions contemplated by this Participation Rights Agreement. 

7. Counterparts. This Participation Rights Agreement may be executed in as many counterparts as the parties hereto deem necessary or
convenient, each of which counterparts shall be deemed an original but all of which, together, shall constitute but one and the same document. 

8. Entire Agreement. This Participation Rights Agreement constitutes the entire agreement among the parties with respect to the subject
matter hereof and supersede all other prior agreements and understandings, both written and oral, between the parties with respect to such subject matter. 

[signature page follows] 







 [signature page] 

If you agree that the foregoing accurately sets forth our agreement, please execute this Participation Rights Agreement in the space provided
below, whereupon it will become a binding contract between us. 
  

			
	ALEXANDRIA EQUITIES, LLC,
	a Delaware limited liability company
		
	 By:
	 	Alexandria Real Estate Equities, Inc.,
a Maryland corporation,
its managing member
		
	 By:
	 	 
	 Name:
	 	 
	 Title:
	 	 


 ACCEPTED AND AGREED TO: 

HOMOLOGY MEDICINES, INC. 

a Delaware corporation 

			
		
	 By:
	 	 
	 Name:
	 	 
	 Title: