Document:

EX-10.20

 Exhibit 10.20 

SUBLEASE 
 BETWEEN

 TWITTER, INC. 

AND 
 SOLID BIOSCIENCES,
LLC 
 141 Portland Street, Cambridge, Massachusetts 

Fifth (5th) Floor 
  

 SUBLEASE 

THIS SUBLEASE (“Sublease”) is entered into as of January 30, 2018 (the “Effective Date”), by and between TWITTER,
INC., a Delaware corporation (“Sublandlord”) and SOLID BIOSCIENCES, LLC, a Delaware limited liability company (“Subtenant”), with reference to the following facts: 

A. Pursuant to that certain Lease dated as of September 10, 2013 (the “Original Master Lease”), as amended by that
certain First Amendment to Lease Agreement dated as of January 24, 2018 (the “First Amendment”) (as amended, the “Master Lease”),Kendall Square Entity, Inc. (“Landlord”), as Landlord, leases to
Sublandlord, as Subtenant, certain space (the “Master Lease Premises”) consisting of 47,631 rentable square feet (“RSF”) and consisting of 15,877 RSF on the fifth (5th) floor of the Building (defined below) (the
“5th Floor Premises”), 15,877 RSF on the sixth (6th) floor of the Building (the “6th Floor Premises”) and 15,877 RSF on the seventh (7th) floor of the Building (the “7th Floor Premises”); as used
herein, the “Building” shall mean the building located at 141 Portland Street, Cambridge, Massachusetts. 
 B. Subtenant
wishes to sublease from Sublandlord, and Sublandlord wishes to sublease to Subtenant, the 5th Floor Premises, said space being more particularly identified and described on the floor plan attached hereto as Exhibit A and incorporated herein
by reference (and hereafter referred to as the “Subleased Premises”). 
 NOW, THEREFORE, in consideration of the foregoing,
and for other good and valuable consideration, the receipt and adequacy of which are hereby acknowledged by the parties, Sublandlord and Subtenant hereby agree as follows: 

1. Sublease. Sublandlord hereby subleases to Subtenant and Subtenant hereby subleases from Sublandlord for the term, at the rental, and
upon all of the conditions set forth herein, the Subleased Premises, together with rights of ingress and egress thereto, and with the right in common with others to use, to the extent applicable, the elevators and common passageways, stairways and
vestibules, and to pass over and park on that portion of land owned by Landlord and designated by Landlord for Sublandlord’s parking. 

2. Term. 
 (a)
Generally. The term of this Sublease (the “Term”) shall commence on the date (the “Commencement Date”) that is the later to occur of (i) the date that Sublandlord delivers possession of the Subleased
Premises to Subtenant with Sublandlord’s Pre-Delivery Work (defined in Section 14(a) below) completed (the “Delivery Date” and such delivery, “Delivery”) and
(ii) the date upon which Sublandlord or Landlord delivers Landlord’s fully executed Consent (as defined in Section 26 of this Sublease) to Subtenant; the parties anticipate that the Commencement Date will be January 15, 2018
(the “Anticipated Commencement Date”). Unless sooner terminated pursuant to any provision hereto, the Term will end on the later of either (x) February 28, 2019 or, (y) if Sublandlord and Landlord mutually execute and
deliver an amendment to the Master Lease pursuant to which the term of the Master Lease is extended to at least February 28, 2022, then, subject to Landlord’s consent, the Term will expire February 28, 2022 (the “Expiration
Date”). Upon the determination of the Commencement 

  
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Date and the Expiration Date, Sublandlord and Subtenant will enter into a letter agreement in the form of Exhibit B attached hereto. If Sublandlord and Landlord fail by March 31, 2018
to mutually execute and deliver an amendment to the Master Lease, pursuant to which the term of the Master Lease is extended to at least February 28, 2022, then Subtenant shall have the right to negotiate directly with Landlord for the
extension of the Expiration Date beyond February 28, 2019. 
 (b) Delivery Conditions. If, as of the date that Sublandlord would
otherwise achieve Delivery as described in clause (i) of Section 2(a) above, Subtenant has not delivered to Sublandlord (x) the prepaid Base Rent pursuant to the provisions of Section 3(a) below, (y) the Security Deposit
pursuant to the provisions of Section 4 below and (z) evidence of Subtenant’s procurement of all insurance coverage required hereunder (the “Delivery Conditions”), then Sublandlord will have no obligation to Deliver
the Subleased Premises to Subtenant, but the failure on the part of Sublandlord to so Deliver possession of the Subleased Premises to Subtenant in such event will not serve to delay the occurrence of the Commencement Date and the commencement of
Subtenant’s obligations to pay Rent (defined below) hereunder. 
 (c) Late Delivery. If the Commencement Date does not occur as
of the Anticipated Commencement Date for any reason other than due to Subtenant’s failure to fulfill the Delivery Conditions, or to execute the Consent, Subtenant shall be entitled to a day-for-day delay in the Rent Commencement Date (defined in Section 3(a) below). 
 (d)
First Right to Negotiate Extension. If both (y) the term of the Master Lease expires more than one (1) month after the Expiration Date and (z) Sublandlord determines in good faith that Sublandlord will not reoccupy the
Subleased Premises for the conduct of Sublandlord’s business following the Expiration Date, Sublandlord will provide written notice to Subtenant of such determination (a “Non-Occupancy
Notice”) no later than three (3) months prior to the Expiration Date; thereafter, Subtenant shall have the right to provide written notice to Sublandlord within fifteen (15) days of Subtenant’s receipt of such notice if it
desires to negotiate to extend the Term. If Subtenant fails to timely notify Sublandlord of Subtenant’s desire to extend the Term, Sublandlord shall be free to negotiate with third parties regarding the sublease of the Subleased Premises on
such terms and conditions as Sublandlord in its good faith discretion may determine to be acceptable. If, however, Subtenant timely notifies Sublandlord of Subtenant’s desire to extend the Term, Subtenant shall have the exclusive right to
negotiate with Sublandlord for a period of two (2) weeks (the “Negotiation Period”) following Subtenant’s notice to Sublandlord, regarding the terms upon which the Term may be so extended, with Subtenant paying the same
rental rate payable by Sublandlord under the Master Lease, for a term to be mutually agreed upon by Sublandlord and Subtenant. During the Negotiation Period, the parties will attempt in good faith to reach agreement on such extension and any
corresponding change to the Security Deposit; if, at the expiration of the Negotiation Period, the parties have not reached an agreement, Sublandlord shall be free to negotiate with third parties regarding the sublease of the Subleased Premises on
such terms and conditions as Sublandlord in its good faith discretion may determine to be acceptable. For avoidance of doubt, if Sublandlord fails to timely deliver a Non-Occupancy Notice but, in fact, has
determined that Sublandlord will not reoccupy the Subleased Premises as described above, Sublandlord will not enter into any sublease for the period following the Expiration Date with any third party for the Subleased Premises without initially
providing Subtenant the right to engage in the negotiation of a potential extension of this Sublease during a Negotiation Period. 

  
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 3. Rent. 

(a) Rent Payments. From and after April 1, 2018 (the “Rent Commencement Date”) Subtenant shall pay to Sublandlord
as base rent for the Subleased Premises during the Term (“Base Rent”) the following: 
  

									
	 Period
	  	Rate Per RSF
Per Annum	 	  	Monthly
Base Rent	 
	 Rent Commencement Date - February 28, 2019
	  	$	60.00	 	  	$	79,385.00	 

 Base Rent shall be paid in advance on the first day of each month of the Term from and after the Rent Commencement Date,
except that Subtenant shall pay one (1) month’s Base Rent to Sublandlord (i.e., $79,385.00) upon execution of this Sublease and delivery of this Sublease to Sublandlord; said pre-paid Base Rent will
be applied to the first (1st) month’s Base Rent due and payable hereunder. If the Term is extended pursuant to the provisions of clause (y) of Section 2(a) above, then, during such extended portion of the Term, Subtenant will pay the
same Base Rent rate per RSF per annum that Sublandlord is obligated to pay pursuant to the provisions of the Master Lease during such extended Term, but in no event will such amounts exceed the following: 

 

					
	 Period
	  	Maximum Base Rent
Per RSF Per Annum	 
	 March 1, 2019 - February 29, 2020
	  	$	78.00	 
	 March 1, 2020 - February 28, 2021
	  	$	79.00	 
	 March 1, 2021 - February 28, 2022
	  	$	80.00	 

 Rent for any partial month shall be prorated as necessary based upon the actual number of days in such month which fall within
the Term. All Rent shall be payable in lawful money of the United States by electronic funds transfer, ACH or wire transfer to an account designated by Sublandlord, or by regular bank check of Subtenant, to Sublandlord at the following address: 

Twitter, Inc. 
 c/o SRS - Cresa
Lease Administration, LLC 
 Inwood National Bank 

P.O. Box 852724 
 Richardson,
Texas 75085 
 or to such other persons or at such other places as Sublandlord may designate in writing. 

(b) Operating Costs. 

(i) Definitions. For purposes of this Sublease and in addition to the terms defined elsewhere in this Sublease, the following terms
shall have the meanings set forth below: 
 (1) “Additional Rent” shall mean the sums payable pursuant to
Section 3(b)(ii) below. 

  
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 (2) “Base Operating Costs” shall mean Operating Costs payable by
Sublandlord to Landlord for the Master Lease Premises during the Base Year. 
 (3) “Base Year” shall mean the
calendar year 2018, however, if the Term is extended as described in clause (y) of Section 2(a) above, then, during such extended portion of the Term, the Base Year hereunder shall be the same Base Year as is applicable under the Master
Lease, as the Master Lease is modified to effect such extension. 
 (4) “Operating Costs” shall mean the aggregate
of Operating Expenses and Taxes (as such terms are defined in the Original Master Lease) charged by Landlord to Sublandlord pursuant to the Master Lease. 

(5) “Rent” shall mean, collectively, Base Rent, Additional Rent, and all other sums payable by Subtenant to
Sublandlord under this Sublease, whether or not expressly designated as “rent”, all of which are deemed and designated as rent pursuant to the terms of this Sublease. 

(6) “Subtenant’s Percentage Share” shall mean 33.33% (i.e., 15,877/47,631); provided, however, that if at any
time the RSF of the Master Lease Premises or the Subleased Premises shall change as a consequence to the change in the physical dimensions of either the Master Lease Premises or the Subleased Premises, then Subtenant’s Percentage Share shall be
recalculated to reflect the ratio, expressed as a percentage, that the RSF of the Subleased Premises then bears to the RSF of the Master Lease Premises. 

(ii) Payment of Additional Rent. In addition to the Base Rent payable hereunder, from and after the expiration of the Base Year,
Subtenant shall pay, as Additional Rent, Subtenant’s Percentage Share of the amount by which Operating Costs payable by Sublandlord for the then current calendar year exceed Base Operating Costs. Sublandlord shall provide Subtenant with written
notice of Sublandlord’s estimate of the amount of Additional Rent per month payable for each calendar year after the Base Year promptly following the Sublandlord’s receipt of Landlord’s estimate of the Operating Costs payable under
the Master Lease. Thereafter, the Additional Rent payable shall be determined and adjusted in accordance with the provisions below. 

(iii) Procedure. The determination and adjustment of Additional Rent payable hereunder shall be made in accordance with the following
procedures: 
 (1) Delivery of Estimate; Payment. Upon receipt of a statement from Landlord specifying the estimated Operating Costs
to be charged to Sublandlord under the Master Lease with respect to each calendar year, or as soon after receipt of such statement as practicable, Sublandlord shall give Subtenant written notice of its estimate of Additional Rent for the ensuing
calendar year, which estimate shall be prepared based on the estimate received from Landlord (as Landlord’s estimate may change from time to time), together with a copy of the statement received from Landlord. On or before the first day of each
month during each calendar year, Subtenant shall pay to Sublandlord as Additional Rent one-twelfth (l/12th) of such estimated amount together with the Base Rent. 

  
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 (2) Sublandlord’s Failure to Deliver Estimate. In the event Sublandlord’s
notice is not given on or before December 1 of the calendar year preceding the calendar year for which Sublandlord’s notice is applicable, as the case may be, then until the calendar month after such notice is delivered by Sublandlord,
Subtenant shall continue to pay to Sublandlord monthly, during the ensuing calendar year, estimated payments equal to the amounts payable hereunder during the calendar year just ended. Upon receipt of any such post-December 1 notice Subtenant shall
(i) commence as of the immediately following calendar month, and continue for the remainder of the calendar year, to pay to Sublandlord monthly such new estimated payments and (ii) if the monthly installment of the new estimate of such
Additional Rent is greater than the monthly installment of the estimate for the previous calendar year, pay to Sublandlord within thirty (30) days of the receipt of such notice an amount equal to the difference of such monthly installment
multiplied by the number of full and partial calendar months of such year preceding the delivery of such notice. 
 (iv) Year End
Reconciliation. Following the receipt by Sublandlord of a final statement of Operating Costs from Landlord with respect to each calendar year, Sublandlord shall deliver to Subtenant a statement of any adjustment to be made for the calendar year
just ended (“Sublandlord’s Annual Statement”), together with a copy of any corresponding Landlord’s statement of actual Operating Expense and Taxes received by Sublandlord (“Landlord’s Statement”). If
on the basis of Sublandlord’s Annual Statement,Subtenant owes an amount that is less than the estimated payments actually made by Subtenant for the calendar year just ended, Sublandlord shall credit such excess to the next payments of Rent
coming due or, if the Sublease Term will expire before such credit offsets the full excess, refund any remaining excess to Subtenant within thirty (30) days after the expiration of the Sublease Term. If on the basis of such Sublandlord’s
Annual Statement Subtenant owes an amount that is more than the estimated payments for the calendar year just ended previously made by Subtenant, Subtenant shall pay the deficiency to Sublandlord within thirty (30) days after delivery of the
Sublandlord’s Annual Statement from Sublandlord to Subtenant. 
 (v) Reliance on Landlord’s Calculations. 

(1) Generally. In calculating Operating Costs payable hereunder by Subtenant, Sublandlord shall have the right to rely upon the
calculations of Landlord made in determining Operating Expenses and Taxes pursuant to the provisions of the Master Lease and Subtenant shall have no direct right to audit or review Landlord’s calculation of Operating Expenses and Taxes. 

(2) Subtenant’s Right to Request Audit. 

a. Notwithstanding the provisions of Section 3(b)(v)(l) above, provided Subtenant is not in Default hereunder and no notice of Default
from Sublandlord to Subtenant is then currently outstanding and uncured, and further provided that Subtenant delivers Subtenant’s Audit Request Notice (defined below) at least thirty (30) days prior to the date of expiration of
Sublandlord’s right to request a review of Landlord’s books and records pursuant to the provisions of Section 5 of Exhibit C to the Original Master Lease, if in 

  
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any year Sublandlord’s Annual Statement reflects an increase in Operating Costs in excess of five percent (5%) over the Operating Costs for the immediately preceding year, Subtenant shall
have the right, to be exercised by written notice delivered to Sublandlord (“Subtenant’s Audit Request Notice”) to request that Sublandlord exercise its rights to review Landlord’s books and records regarding Operating
Expenses and Taxes as set forth in Section 5 of Exhibit C to the Original Master Lease. In such event, Sublandlord will promptly exercise Sublandlord’s rights set forth in Section 5 of Exhibit C to the Original Master Lease. In the
event of any such exercise by Sublandlord pursuant to the provisions of this Section 3(b)(v)(2) the following provisions will apply: 

b. Sublandlord will select a certified public accountant selected by Sublandlord to review Landlord’s books and records in accordance
with the provisions of Section 5 of Exhibit C to the Original Master Lease, following which Sublandlord and Subtenant will confer in good faith regarding the results of such review; thereafter, if the parties deem it necessary, then
Sublandlord, will endeavor in good faith to resolve with Landlord any necessary clarification or dispute raised by Subtenant in Subtenant’s Audit Request Notice. All costs of any such review shall be borne solely by Subtenant as additional Rent
hereunder, unless Landlord is liable for the costs of the audit pursuant to Section 5 of Exhibit C to the Original Master Lease. Any additional amounts will be due within thirty (30) days after Sublandlord’s delivery of an invoice to
Subtenant. If, following the completion of any such audit, it is determined that Sublandlord is entitled to the reimbursement of Operating Expenses and Taxes under the Master Lease, any such reimbursement shall be applied, first, to the audit costs
previously paid by Subtenant, and second, to any such reasonable out of pocket cost incurred by Sublandlord which have not then been reimbursed by Subtenant or Landlord to Sublandlord, and, thereafter, the remaining refund will be equitably
allocated between Sublandlord and Subtenant in accordance with the ratio that their respective overpayments of Operating Expenses and Taxes (in the case of Sublandlord) and Operating Costs (in the case of Subtenant) compare to each other. For
avoidance of doubt, if, as of the date that Subtenant delivers a Subtenant’s Audit Request, Sublandlord has already notified Landlord of Sublandlord’s exercise of the review rights described in Section 5 of Exhibit C to the Original
Master Lease, then Subtenant shall have no independent right to require any such review of Landlord’s books and records, but Sublandlord agrees to: (A) promptly provide Subtenant with any report prepared by Sublandlord’s accounting
firm or accountant on the basis of any such review of Landlord’s books and records (subject to Landlord’s consent to such disclosure) and, (B) allocate to Subtenant any net refund of Operating Expenses and Taxes attributable to an
overpayment by Sublandlord following Sublandlord’s recovery from any aggregate refund of all costs associated with such review, as may then be equitable given any corresponding overpayment of Operating Costs by Subtenant and in such event,
Subtenant shall have no obligation to reimburse Sublandlord for the costs of the review initiated solely by Sublandlord. 
 (vi)
Survival. The expiration or earlier termination of this Sublease shall not affect the obligations of Sublandlord and Subtenant pursuant to this Section 3(b), and such obligations shall survive, remain to be performed after, any
expiration or earlier termination of this Sublease. 

  
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 (c) Electricity. Pursuant to the Master Lease, the cost of all electrical consumption
in the Master Lease Premises is borne by Sublandlord. During the Term, Subtenant shall be obligated to pay for the cost of electrical consumption in the Subleased Premises (i.e., such cost will not be included in Operating Costs). Sublandlord will
invoice Subtenant, on a monthly basis, for the cost of the electrical consumption as shown on an existing submeter measuring electrical consumption in the Subleased Premises. Subtenant shall pay such costs as additional Rent hereunder within thirty
(30) days following Sublandlord’s delivery of an invoice therefor to Subtenant. 
 (d) Janitorial. As of the Effective
Date, Sublandlord (as opposed to Landlord), at Sublandlord’s sole cost and expense, provides janitorial services to the Subleased Premises. During the Sublease Term, Subtenant will provide janitorial services to the Subleased Premises using a
janitorial contractor approved in advance by Sublandlord (not to be unreasonably withheld) and Landlord pursuant to a separate contract between Subtenant and such janitorial contractor. Subtenant will be responsible for the cost of such janitorial
service. Such services will be provided in a manner reasonably commensurate in scope, level of service and frequency of services as, and not less than the scope, level of service and frequency of services than, the services provided by Landlord
elsewhere in the Building. 
 4. Security Deposit. Concurrently with Subtenant’s execution of this Sublease, Subtenant shall
deposit with Sublandlord the sum of $79,385.00 (the “Security Deposit”); however, if the Term is extended pursuant to the provisions of clause (y) of Section 2(a) above, the Security Deposit will be increased to the sum of
$209,047.00, and Subtenant will deliver to Sublandlord the sum of $129,662.17 within ten (10) calendar days following Sublandlord’s request. The Security Deposit shall be held by Sublandlord as security for the faithful performance by
Subtenant of all the provisions of this Sublease to be performed or observed by Subtenant. If a Default exists hereunder, Sublandlord may use, apply or retain all or any portion of the Security Deposit for the payment of any past-due sum or for the payment of any other sum to which Sublandlord may become obligated by reason of Subtenant’s Default, or to compensate Sublandlord for any loss or damage which Sublandlord may suffer
thereby. If Sublandlord so uses or applies all or any portion of the Security Deposit, Subtenant shall within ten (10) days after demand therefor deposit cash with Sublandlord in an amount sufficient to restore the Security Deposit to the full
amount thereof and Subtenant’s failure to do so shall be a Default without the necessity of the passage of any additional cure period. The Security Deposit, or so much thereof as has not theretofore been applied by Sublandlord, shall be
returned, without interest, to Subtenant (or, at Sublandlord’s option, to the last assignee, if any, of Subtenant’s interest hereunder) within thirty (30) days following the later to occur of (a) the expiration of the Term, and
(b) Subtenant’s vacation from the Subleased Premises and completion of all removal,repair and restoration obligations that may be required by this Sublease. No trust relationship is created herein between Sublandlord and Subtenant with
respect to the Security Deposit. 
 5. Use and Occupancy. 

(a) Use. The Subleased Premises shall be used and occupied only for general office use purposes and other uses provided under the
Master Lease. 

  
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 (b) Compliance with Master Lease. Subtenant will occupy the Subleased Premises in
accordance with the terms of the Master Lease and will not suffer to be done, or omit to do, any act which may result in a violation of or an Event of Default (as defined in the Original Master Lease) under the Master Lease, or render Sublandlord
liable for any damage, charge or expense thereunder. Subtenant will indemnify, defend protect and hold Sublandlord harmless from and against any loss, cost, damage or liability (including reasonable attorneys’ fees) of any kind or nature
arising out of, by reason of, or resulting from, Subtenant’s failure to perform or observe any of the terms and conditions of the Master Lease (unless such failure is due to Sublandlord’s breach of this Sublease or the Master Lease) or
this Sublease. Sublandlord will indemnify, defend protect and hold Subtenant harmless from and against any loss, cost, damage or liability (including reasonable attorneys’ fees) of any kind or nature arising out of, by reason of, or resulting
from, Sublandlord’s failure to perform or observe any of the terms and conditions of the Master Lease or this Sublease (unless such failure is due to Subtenant’s breach of this Sublease or the Master Lease). Any other provision in this
Sublease to the contrary notwithstanding, Subtenant shall pay to Sublandlord as Rent hereunder any and all sums which Sublandlord may be required to pay the Landlord in accordance with the Master Lease arising out of a request by Subtenant for, or
the use by Subtenant of, additional or over-standard Building services from Landlord to the extent attributable to the Subleased Premises (for example, but not by way of limitation, charges associated with after-hour HVAC usage and overstandard
electrical charges). 
 (c) Landlord’s Obligations. Subtenant agrees that Sublandlord shall not be required to perform any of
the covenants, agreements and/or obligations of Landlord under the Master Lease, including, without limitation, the provision of services provided in the Master Lease, and, insofar as any of the covenants, agreements and obligations of Sublandlord
hereunder are required to be performed under the Master Lease by Landlord thereunder, Subtenant acknowledges and agrees that Sublandlord shall be entitled to look to Landlord for such performance; provided that Sublandlord shall reasonably cooperate
with Subtenant to coordinate any request for services or enforcing any other covenant of Landlord under the Master Lease. In addition, Sublandlord shall have no obligation to perform any repairs or any other obligation of Landlord under the Master
Lease, nor shall any representations or warranties made by Landlord under the Master Lease be deemed to have been made by Sublandlord. Sublandlord shall not be responsible for any failure or interruption, for any reason whatsoever, of the services
or facilities that may be appurtenant to or supplied at the Building by Landlord or otherwise, including, without limitation, heat, air conditioning, ventilation, life-safety, water, electricity, elevator service and cleaning service, if any; and no
failure to furnish, or interruption of, any such services or facilities shall give rise to any (i) abatement, diminution or reduction of Subtenant’s obligations under this Sublease (provided that if Sublandlord is entitled to an abatement
of Rent payable under the Master Lease with respect to the Subleased Premises as a result of an interruption in services to the Subleased Premises, then Subtenant will be entitled to a parallel abatement of Rent payable hereunder) or
(ii) liability on the part of Sublandlord. Notwithstanding the foregoing, Sublandlord shall use good faith efforts, under the circumstances, to secure such performance upon Subtenant’s request to Sublandlord to do so and shall thereafter
diligently prosecute such performance on the part of Landlord; provided, however, that this sentence will not be interpreted to require Sublandlord to commence any legal proceeding, arbitration or any other similar form of process unless
Sublandlord, in Sublandlord’s sole discretion, determines that commencement of such action is necessary and appropriate. 

  
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 (d) Access. Access to the Building is provided through the use of a key fob that is
provided by Landlord (Sublandlord shall, at no cost to Sublandlord, coordinate Subtenant’s procurement of such key fobs from Landlord); the charge for each Landlord-issued key fob is, as of the Effective Date, $25.00, and Subtenant will be
responsible for the costs of any such key fobs. Landlord-issued key fobs are also used to access the Building’s parking garage. Subtenant acknowledges that elevator access to the fifth (5th) floor of the Building is, as of the Effective Date,
controlled by Sublandlord’s card reader system; (i.e., an individual cannot cause the elevator to stop at the fifth (5th) floor without using a Sublandlord-issued access badge). Prior to Delivery, Sublandlord, at Sublandlord’s sole cost
and expense, shall terminate Sublandlord’s elevator access controls with respect to the fifth (5th) floor such that the fifth (5th) floor will have open access. Additionally, the Subleased Premises currently has several card readers and cameras
installed; Sublandlord will leave these devices and the associated cabling in the Subleased Premises upon delivery to Subtenant. Sublandlord’s card reader system cannot be reprogrammed to differentiate Subtenant access cards from the access
cards of Sublandlord and other occupants of the Building, but Subtenant will be entitled to install, and Sublandlord hereby approves in concept, its own “head end” security system (subject to any necessary approval of plans and
specifications therefor to be obtained from Sublandlord to the extent required under Section 14(b) below and from Landlord to the extent required under the Master Lease) which Subtenant will be required to remove at the end of the Term.
Sublandlord will respond to any request from Subtenant for approval of Subtenant’s proposed security system within five (5) business days and will use reasonable efforts to obtain Landlord’s agreement to expedite its review of such
security system (Subtenant acknowledges that Landlord is not required to respond in five (5) business days). 
 6. Master Lease and
Sublease Terms. 
 (a) Subject to Master Lease. This Sublease is and shall be at all times subject and subordinate to the Master
Lease. Subtenant acknowledges that Subtenant has reviewed and is familiar with all of the terms, agreements, covenants and conditions of the Master Lease. During the Term and for all periods subsequent thereto with respect to obligations which have
arisen prior to the termination of this Sublease, Subtenant agrees to perform and comply with, for the benefit of Sublandlord and Landlord, the obligations of Sublandlord under the Master Lease which pertain to the Subleased Premises and/or this
Sublease, except for those provisions of the Master Lease which are directly contradicted by this Sublease, in which event the terms of this Sublease shall control over the Master Lease. 

(b) Incorporation of Terms of Master Lease. The terms, conditions and respective obligations of Sublandlord and Subtenant to each other
under this Sublease shall be the terms and conditions of the Master Lease, except for those provisions of the Master Lease which are directly contradicted by this Sublease, in which event the terms of this Sublease shall control over the Master
Lease. Therefore, for the purposes of this Sublease, wherever in the Master Lease the word “Landlord” is used it shall be deemed to mean Sublandlord and wherever in the Master Lease the word “Tenant” is used it shall be deemed to
mean Subtenant. Additionally, wherever in the Master Lease the word “Premises” is used it shall be deemed to mean the Subleased Premises. Any non-liability, release, indemnity or hold harmless
provision in the Master Lease for the benefit of Landlord that is incorporated herein by reference, shall be deemed to inure to the benefit of Sublandlord, Landlord, and any other person intended to be benefited by said provision, for the purpose of
incorporation by reference in this Sublease. Any right of Landlord under the Master Lease (a) of access or inspection, (b) to do work in the Master 

  
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Lease Premises or in the Building, (c) in respect of rules and regulations, and construction standards, as updated from time to time, which are incorporated herein by reference, shall be
deemed to inure to the benefit of Sublandlord, Landlord, and any other person intended to be benefited by said provision, for the purpose of incorporation by reference in this Sublease. 

(c) Modifications. For the purposes of incorporation herein, the terms of the Master Lease are subject to the following additional
modifications: 
 (i) Approvals. In all provisions of the Master Lease (under the terms thereof and without regard to modifications
thereof for purposes of incorporation into this Sublease) requiring the approval or consent of Landlord, Subtenant shall be required to obtain the approval or consent of both Sublandlord and Landlord. 

(ii) Deliveries. In all provisions of the Master Lease requiring Tenant to submit, exhibit to, supply or provide Landlord with
evidence, certificates, or any other matter or thing, Subtenant shall be required to submit, exhibit to, supply or provide, as the case may be,the same to both Landlord and Sublandlord. 

(iii) Damage; Condemnation. Sublandlord shall have no obligation to restore or rebuild any portion of the Subleased Premises after any
destruction or taking by eminent domain. Any rights of Subtenant to abatement of rent shall be conditioned upon Sublandlord’s ability to abate rent for the Subleased Premises under the terms of the Master Lease. 

(iv) Insurance. In all provisions of the Master Lease requiring Tenant to designate Landlord as an additional or named insured on its
insurance policy, Subtenant shall be required to so designate Landlord and Sublandlord on its insurance policy. Sublandlord shall have no obligation to maintain the insurance to be maintained by Landlord under the Master Lease. 

(d) Exclusions. Notwithstanding the terms of Section 6(b) above, Subtenant shall have no rights nor obligations under the
following parts, Sections and Exhibits of the Master Lease: 
 (i) Original Master Lease: Articles 1, 2, 3 (except Section 3.2),
4 (except to the extent necessary to implement Section 3(b)(ii) above), 5, Sections 7.1 (reference to “Delivery Condition” only), 7.2, 10.1 (references to “Second Request” and deemed approval of Alterations only), 10.4
(superceded by Section 14.1 below), 10.5, 10.6, 11.2 (provided that Sublandlord will request Building passes for Subtenant’s employees from Landlord and will use reasonable efforts to assist Subtenant in obtaining such Building passes from
Landlord), 12.2, 13.1 (references to deemed approval only), 16.4, 17.5 (provided that if Sublandlord is entitled to an abatement of rent payable under the Master Lease pursuant to Section 17.5 as a consequence of an Abatement Event [defined in
the Original Master Lease] which affects the Subleased Premises, Subtenant will be entitled to a parallel abatement of Rent payable hereunder), Articles 18 (clauses (a) and (b) only, which are superceded by Section 8 below), 22, 24, 27,
28, Section 29.5, Articles 30 (except to the extent necessary to implement Section 16 below), 31 and 32, Exhibit A, Exhibit B, Exhibit C (except to the extent necessary to implement Section 3(b) above), Exhibit E, Exhibit F, Exhibit
G, Exhibit H, Exhibit I; and 

  
 10 

 (ii) First Amendment: Section 3, Section 4 (except to the extent necessary to
implement Section 3(b)(ii) above), Sections 5, 8, 9, 10, 11 and 12 and Exhibit A. 
 (e) Sublandlord’s Representations.
Sublandlord represents to Subtenant that (i) attached hereto as Exhibit D is a true, accurate and complete (subject to redaction of certain financial terms) copy of the Master Lease and all amendments thereto and the same have not been
further modified, (ii) Sublandlord is the “Tenant” under the Master Lease, (iii) as of the Effective Date, the Master Lease is in full force and effect, (iv) as of the Effective Date, Sublandlord is not in default in the
payment of any rent or other sums due under the Master Lease, (A) Sublandlord has not received any notice of default under the Master Lease which remains uncured as of the Effective Date, (B) to the best of Sublandlord’s knowledge,
Landlord is not in default thereunder, and (C) to the best of Sublandlord’s knowledge, no Hazardous Materials are present in the Subleased Premises in violation of any of the provisions of the Master Lease, and (v) subject to the
consent of Landlord, Sublandlord has full right and authority to sublease the Subleased Premises to Subtenant on the terms and conditions set forth herein. 

(f) Sublandlord’s Compliance with Master Lease. Sublandlord shall perform all covenants and obligations required to be performed
by Sublandlord under the Master Lease in accordance with the terms and provisions thereof and, so long as Subtenant is not in Default hereunder, shall not cause the Master Lease to terminate or expire before the scheduled date of expiration of this
Sublease. Upon Sublandlord’s knowledge thereof, Sublandlord shall promptly provide Subtenant with written notice of any violation or default of any of the terms of the Master Lease and provide Subtenant with a copy of any default notices
received by Sublandlord from Landlord. 
 7. Assignment and Subletting. Subtenant shall not assign Subtenant’s interest in this
Sublease or further sublet all or any part of the Subleased Premises except subject to and in compliance with all of the terms and conditions of the Master Lease, and Sublandlord (in addition to Landlord) shall have the same rights with respect to
assignment and subleasing as Landlord has under the Master Lease; provided, however that Sublandlord shall not unreasonably withhold, condition or delay its consent to any such proposed assignment or sublease. Subtenant shall pay all fees and costs
payable to Landlord pursuant to the Master Lease in connection with any proposed assignment, sublease or transfer of the Subleased Premises (or any portion), together with all of Sublandlord’s reasonable out-of-pocket costs relating to any proposed assignment, sublease or transfer of the Subleased Premises (or any portion) regardless of whether consent is granted (or is required), and the effectiveness of any
assignment, sublease or transfer by Subtenant will be conditioned upon Landlord’s and Sublandlord’s receipt of all such fees and costs. Subtenant agrees that it would be reasonable for Sublandlord to refuse to consent to any assignment of
this Sublease or a sub-subletting of the Subleased Premises to a Competitor (defined below) of Sublandlord or an Affiliate of any such Competitor. If, at any time, Subtenant desires to sublease all or any
portion of the Subleased Premises or assign its interest in this Sublease to a particular entity and desires to have Sublandlord determine whether such entity is a Competitor, Subtenant may deliver notice to Sublandlord stating the identity of the
proposed assignee or subtenant and Sublandlord will notify Subtenant whether such entity is a Competitor within ten (10) business days of Sublandlord’s receipt of such request. As used herein, a “Competitor” is an entity
(or an affiliate of an entity) which Sublandlord deems to be a business competitor of Sublandlord or any of Sublandlord’s affiliates. 

  
 11 

 8. Default. Except as expressly set forth herein, Subtenant shall perform all
obligations in respect of the Subleased Premises that Sublandlord would be required to perform pursuant to the Master Lease. It shall constitute a “Default” hereunder if Subtenant fails to perform any obligation hereunder
(including, without limitation, the obligation to pay Rent), or any obligation under the Master Lease which has been incorporated herein by reference, and, in each instance, Subtenant has not remedied such failure (i) in the case of any
monetary Default, three (3) business days after delivery of written notice and (ii) in the case of any other Default, ten (10) business days after delivery of written notice; provided, however, that if the Default is incapable of cure
within ten (10) business days, then for so long as Sublandlord has not received notice from Landlord stating that Landlord will treat such Default as an “Event of Default” under the Master Lease, Subtenant shall not be in Default
hereunder if Subtenant commences the cure within the ten (10) business day period and thereafter diligently prosecutes the cure to completion; however, if at any time Sublandlord receives notice from Landlord that the Default will be treated as
an “Event of Default” under the Master Lease, Subtenant’s cure period will immediately be deemed to expire ten (10) days before the date of expiration of Sublandlord’s cure period as set forth in Landlord’s notice of
default to Sublandlord. 
 9. Remedies. In the event of any Default hereunder by Subtenant, Sublandlord shall have all remedies
provided to the “Landlord” in the Master Lease as if a default had occurred thereunder and all other rights and remedies otherwise available at law and in equity. Sublandlord may resort to its remedies cumulatively or in the
alternative. 
 10. Right to Cure Defaults. If Subtenant fails to perform any of its obligations under this Sublease. after
expiration of applicable grace or cure periods, then Sublandlord may, but shall not be obligated to, perform any such obligations for Subtenant’s account. All reasonable costs and expenses incurred by Sublandlord in performing any such
act for the account of Subtenant shall be deemed Rent payable by Subtenant to Sublandlord upon demand, together with interest thereon at the lesser of (i) the Default Rate (as defined in the Original Master Lease) per annum or
(ii) the maximum rate allowable under law from the date of the expenditure until repaid. If Sublandlord undertakes to perform any of Subtenant’s obligations for the account of Subtenant pursuant hereto, the taking of such action shall not
constitute a waiver of any of Sublandlord’s remedies. 
 11. Consents and Approvals. In any instance when Sublandlord’s
consent or approval is required under this Sublease, Sublandlord’s refusal to consent to or approve any matter or thing shall be deemed reasonable if, among other matters, such consent or approval is required under the provisions of the
Master Lease incorporated herein by reference but has not been obtained from Landlord. Except as otherwise provided herein, Sublandlord shall not unreasonably withhold, condition or delay its consent to or approval of a matter if such consent or
approval is required under the provisions of the Master Lease and Landlord has consented to or approved of such matter. 

  
 12 

 12. Liability. 

(a) Limitation of Liability. Notwithstanding any other term or provision of this Sublease, the liability of Sublandlord to Subtenant
for any default in Sublandlord’s obligations under this Sublease shall be limited to actual, direct damages, and under no circumstances shall Subtenant, its partners, members, shareholders, directors, agents, officers, employees, contractors,
sublessees, successors and/or assigns be entitled to recover from Sublandlord (or otherwise be indemnified by Sublandlord) for (i) any losses, costs, claims, causes of action, damages or other liability incurred in connection with a failure of
Landlord, its partners, members, shareholders, directors, agents, officers, employees, contractors, successors and /or assigns to perform or cause to be performed Landlord’s obligations under the Master Lease, (ii) lost revenues, lost
profit or other consequential, special or punitive damages arising in connection with this Sublease for any reason, or (iii) any damages or other liability arising from or incurred in connection with the condition of the Subleased Premises or
suitability of the Subleased Premises for Subtenant’s intended uses. Subtenant shall, however, have the right to seek any injunctive or other equitable remedies as may be available to Subtenant under applicable law. Notwithstanding any other
term or provision of this Sublease, except as set forth below, the liability of Subtenant to Sublandlord for any default in Subtenant’s obligations under this Sublease shall be limited to actual, direct damages, and under no circumstances shall
Sublandlord, its partners, members, shareholders, directors, agents, officers, employees, contractors, sublessees, successors and/or assigns be entitled to recover from Subtenant (or otherwise be indemnified by Subtenant) for lost revenues, lost
profit or other consequential, special or punitive damages arising in connection with this Sublease for any reason; the foregoing limitation will not, however, apply to the liability of Subtenant with respect to any holding over in the Subleased
Premises by Subtenant beyond the expiration or sooner termination of this Sublease or the use by Subtenant of Hazardous Material (defined in Article 8 of the Original Master Lease) in violation of the provisions of the Master Lease. Notwithstanding
any other term or provision of this Sublease, no personal liability shall at any time be asserted or enforceable against Sublandlord’s shareholders, directors, officers, or partners on account of any of Sublandlord’s obligations or actions
under this Sublease. Notwithstanding any other term or provision of this Sublease, no personal liability shall at any time be asserted or enforceable against Subtenant’s shareholders, directors, officers, or partners on account of any of
Subtenant’s obligations or actions under this Sublease. In the event of any assignment or transfer of the Sublandlord’s interest under this Sublease, Sublandlord shall be and hereby is entirely relieved of all covenants and obligations of
Sublandlord hereunder accruing subsequent to the date of the transfer and it shall be deemed and construed, without further agreement between the parties hereto, that any transferee has assumed and shall carry out all covenants and obligations
thereafter to be performed by Sublandlord hereunder. Sublandlord may transfer and deliver any then existing Security Deposit or Letter of Credit, as applicable, to the transferee of Sublandlord’s interest under this Sublease, and thereupon
Sublandlord shall be discharged from any further liability with respect thereto. 
 (b) Sublandlord Default. Sublandlord shall be in
default hereunder only if Sublandlord has not commenced and pursued with reasonable diligence the cure of any failure of Sublandlord to meet its obligations hereunder within thirty (30) days after the receipt by Sublandlord of written notice
from Subtenant. In no event shall Subtenant have the right to terminate or rescind this Sublease as a result of Sublandlord’s default as to any covenant or agreement contained in this Sublease. Subtenant hereby waives such remedies of
termination and rescission. 

  
 13 

 13. Attorneys’ Fees. If Sublandlord or Subtenant brings an action to enforce the
terms hereof or to declare rights hereunder, the prevailing party who recovers substantially all of the damages, equitable relief or other remedy sought in any such action on trial and appeal shall be entitled to receive from the other party its
costs associated therewith, including, without limitation, reasonable attorney’s fees and costs from the other party. Without limiting the generality of the foregoing, if Sublandlord utilizes the services of an attorney for the purpose of
collecting any Rent hereunder which is, in fact, past due and unpaid by Subtenant, Subtenant will be obligated to pay Sublandlord reasonable actual attorneys’ fees incurred in connection therewith, irrespective of whether any legal action may
be commenced or filed by Sublandlord. 
 14. Delivery of Possession. 

(a) Generally. Sublandlord shall deliver, and Subtenant shall accept, possession of the Subleased Premises in their “AS IS”
condition as the Subleased Premises exists on the Effective Date, but broom clean, free of all occupants; provided however, that prior to Delivery, Sublandlord will (i) relocate the MDF room equipment currently located in the Subleased
Premises, (ii) install a barrier enclosing the interconnecting stairwell between the fifth (5th) floor and the sixth (6th) floor, (iii) leave all cabling located within the Subleased Premises but will remove all network equipment (i.e.,
WAPS, network gear in IDF’s, etc.) (collectively, “Sublandlord’s Pre-Delivery Work”). To Sublandlord’s knowledge, the Building Systems (defined in the Original Master
Lease) serving the Subleased Premises, as well as the existing lighting fixtures therein, will be in good working order and condition as of the date of Sublandlord’s delivery of the Subleased Premises to Subtenant. All of Sublandlord’s Pre-Delivery Work shall be done (1) at Sublandlord’s sole cost and expense, (2) in a workmanlike manner, and (3) in accordance with all applicable laws. Except for Sublandlord’s Pre-Delivery Work, Sublandlord shall have no obligation to furnish, render or supply any work, labor, services, materials, furniture, other than the Furniture (defined below), fixtures, equipment, decorations or
other items to make the Subleased Premises ready or suitable for Subtenant’s occupancy. Sublandlord does not represent or warrant that any cabling located in the Subleased Premises is suitable for Subtenant’s use. Subtenant acknowledges
that Landlord may require that Sublandlord, on or about the expiration of the Master Lease and at no cost to Subtenant, perform restoration work related to the stairwell between the fifth (5th) floor and sixth (6th) floor, and in such event,
Sublandlord will provide notice to Subtenant and use reasonable efforts to minimize any disruption to Subtenant’s business operations; Subtenant will reasonably cooperate with Sublandlord’s stairway work. Additionally, Sublandlord and
Subtenant will mutually cooperate during the performance of any such work to limit access from the sixth (6th) floor to the fifth (5th) floor, including cooperating to establish access procedures to be followed by Sublandlord’s vendors who need
access to the fifth (5th) floor in order to perform such work. Access from the sixth (6th) floor to the fifth (5th) floor shall be limited to only that which is necessary to conduct the stairway work and such access shall be completely prohibited
upon completion of the stairway work, and all work and procedures that may reasonably be required to effectuate such limitation on access shall be at Sublandlord’s sole cost and expense. In making and executing this Sublease, Subtenant has
relied solely on such investigations, examinations and inspections as Subtenant has chosen to make or has made and has not relied on any representation or warranty 

  
 14 

 
concerning the Subleased Premises or the Building, except as expressly set forth in this Sublease. Subtenant acknowledges that Sublandlord has afforded Subtenant the opportunity for full and
complete investigations, examinations and inspections of the Subleased Premises and the common areas of the Building. Subtenant acknowledges that it is not authorized to make or do any alterations or improvements in or to the Subleased Premises
except as permitted by the provisions of this Sublease and the Master Lease and that upon termination of this Sublease, Subtenant shall deliver the Subleased Premises to Sublandlord in the same condition as the Subleased Premises were at the
commencement of the Term, reasonable wear and tear, casualty and condemnation excepted; Subtenant acknowledges that Subtenant shall, at either Sublandlord’s election (to be made, if at all, concurrently with Sublandlord’s approval of any
applicable Subtenant Improvements (defined below) or Landlord’s election), remove from the Subleased Premises some or all of the Subtenant Improvements constructed therein by Subtenant. Additionally, at Subtenant’s cost, Subtenant will
remove all telecommunications and data cabling installed by or for the benefit of Subtenant. Sublandlord acknowledges that Subtenant intends to construct or install eight (8) modular, demountable private offices in the Subleased Premises (the
“Modular Offices”); Sublandlord’s consent to the installation of Modular Offices will not be unreasonably withheld. 

(b) Subtenant’s Improvements. 

(i) Generally. If Subtenant desires to construct improvements within the Subleased Premises (“Subtenant
Improvements”), all Subtenant Improvements will be carried out in accordance with the applicable provisions of the Master Lease and Landlord’s then-current construction guidelines. Sublandlord will have the right to reasonably
approve the plans, specifications and contractor submittals for any proposed Subtenant Improvements, as well as any architects/designers and contractors whom Subtenant proposes to retain to perform such work. Subtenant will submit all such
information for Sublandlord’s review and written approval prior to commencement of any such work; Sublandlord will similarly submit such information to Landlord for review and approval. Subtenant will bear all costs imposed by Landlord under
the Master Lease, as well as all reasonable costs incurred by Sublandlord, in connection with any Subtenant Improvements. Promptly following the completion of any Subtenant Improvements or subsequent alterations or additions by or on behalf of
Subtenant, Subtenant will deliver to Sublandlord two (2) sets of reproducible “as built” drawings of such work, together with a CAD file of the “as-built” drawings meeting
Sublandlord’s (CAD Format Requirements (defined below). Subtenant acknowledges that it is not authorized to make or perform any alterations or improvements in or to the Subleased Premises except as permitted by the provisions of this Sublease
and the Master Lease and that upon termination of this Sublease, Subtenant may be obligated to remove from the Subleased Premises any Alterations. Subtenant expressly acknowledges that, in addition to Landlord’s rights under the Master Lease,
Sublandlord will have the right to require that Subtenant remove any Subtenant Improvement constructed by or on behalf of Subtenant on or before the date of expiration or sooner termination of this Sublease; for the purposes of this sentence, the
provisions of Section 10.4 of the Original Master Lease restricting removal obligations to “Specialty Alterations” (as defined in the Original Master Lease) constructed therein by Subtenant will not be deemed to limit
Sublandlord’s right to require removal of any Subtenant Improvements, in being acknowledged that Subtenant will be required to remove any Subtenant Improvements (and restore the applicable area(s) to its (their) condition existing prior to the
installation of such Subtenant 

  
 15 

 
Improvements) if so elected (a) by Landlord pursuant to the terms of the Master Lease or (b) by Sublandlord. Notwithstanding the foregoing, (x) Sublandlord agrees that if Subtenant
expressly requests Sublandlord’s determination as to whether any Subtenant Improvement(s) will be required to be removed at the expiration or sooner termination of this Sublease (specifically referencing this Section 14(b)(i)), at
Subtenant’s written request for the consent to such Subtenant Improvement(s), Sublandlord will make its determination concurrently with Sublandlord’s approval of such Subtenant Improvement(s) (assuming that such Subtenant Improvement(s) is
approved by Sublandlord) and (y) in no event will Subtenant be obligated to remove any improvements existing in the Subleased Premises as of the date that Sublandlord delivers the Subleased Premises to Subtenant. As used herein,
“Sublandlord’s CAD Format Requirements” shall mean, as of the Effective Date (but subject to subsequent adjustment) (a) the version is no later than current Autodesk version of AutoCAD plus the most recent release version,
(b) files must be unlocked and fully accessible (no “cad-lock”, read-only, password protected or “signature” files), (c) files must be in “dwg” format, and (d) if the
data was electronically in a non-Autodesk product, then files must be converted into “dwg” files when given to Sublandlord. 

(ii) Code-Required Work. If the performance of any Subtenant Improvements or other work by Subtenant within the Subleased Premises
“triggers” a requirement for code-related upgrades to or improvements of any portion of the Building, Subtenant shall be responsible for the cost of such code-required upgrade or improvements. 

15. Holding Over. If Subtenant fails to surrender the Subleased Premises at the expiration or earlier termination of this Sublease,
occupancy of the Subleased Premises after the termination or expiration shall be that of a tenancy at sufferance. Subtenant’s occupancy of the Subleased Premises during the holdover shall be subject to all the terms and provisions of this
Sublease and Subtenant shall pay an amount equal to 150% of the sum of the Base Rent due for the period immediately preceding the holdover. No holdover by Subtenant or payment by Subtenant after the expiration or early termination of this Sublease
shall be construed to extend the Term or prevent Sublandlord from immediate recovery of possession of the Subleased Premises by summary proceedings or otherwise. In addition to the payment of the amounts provided above, if Sublandlord is unable to
deliver possession of the Subleased Premises to a new subtenant or to Landlord, as the case may be, or to perform improvements for a new subtenant, as a result of Subtenant’s holdover, Subtenant shall be liable to Sublandlord for all damages,
including, without limitation, consequential damages, that Sublandlord suffers from the holdover; Subtenant expressly acknowledges that such damages may include all of the holdover rent charged by Landlord under the Master Lease as a result of
Subtenant’s holdover, which Master Lease holdover rent may apply to the entire Master Lease Premises. 
 16. Parking. During the
Term, Subtenant shall have the right, but not the obligation, to initially use up to sixteen (16) of the parking spaces allocated to Sublandlord pursuant to the Master Lease and Subtenant will be responsible for the current monthly rate charged
by Landlord or Landlord’s parking garage operator (without any mark-up by Sublandlord) for such spaces that Subtenant elects to lease, as additional Rent. If and to the extent that Subtenant does not
initially use any of said sixteen (16) spaces, but subsequently desires to use some or all of those spaces which Subtenant did not initially use, Sublandlord will use reasonable efforts, at Subtenant’s sole cost, to assist Subtenant in
obtaining the rights to such spaces, but Sublandlord 

  
 16 

 
does not guaranty that such spaces will be available, and Sublandlord will have no liability for any lack of availability of such spaces, Subtenant expressly acknowledges that Subtenant will be
required to pay Landlord or Landlord’s parking garage operator for any such spaces which Subtenant initially elects to use prior to the commencement of Subtenant’s obligation to pay Base Rent hereunder. 

17. Notices: Any notice by either party to the other required, permitted or provided for herein shall be valid only if in writing and
shall be deemed to be duly given only if (a) delivered personally, or (b) sent by means of Federal Express, UPS Next Day Air or another reputable express mail delivery service guaranteeing next day delivery, or (c) sent by United
States certified or registered mail, return receipt requested, addressed: (i) if to Sublandlord, at the following addresses: 
  

			
		 	Twitter, Inc.
		 	1355 Market Street, Suite 900
		 	San Francisco, California 94103
		 	Attn:     Legal Department
		
	with a copy to:	 	
		 	Twitter, Inc.
		 	1355 Market Street, Suite 900
		 	San Francisco, California 94103
		 	Attn:     Head of Real Estate Workplace
		
	and with a copy to:	 	
		 	Shartsis Friese LLP
		 	One Maritime Plaza, 18th Floor
		 	San Francisco, California 94111
		 	Attn:      Jonathan M. Kennedy and
		 	     Kathleen K. Bryski

 

			
	and (ii) if to Subtenant, at the following addresses:
		
	Prior to the Commencement Date:	 	161 First Street, Suite 3A
		 	Cambridge, MA 02142
		 	Attn: General Counsel
		
	From and after the Commencement Date:	 	141 Portland Street, 5th Fl.
		 	Cambridge, MA 02139
		 	Attn: General Counsel

 or at such other address for either party as that party may designate by notice to the other. A notice shall be deemed given
and effective, if delivered personally, upon hand delivery thereof (unless such delivery takes place after hours or on a holiday or weekend, in which event the notice shall be deemed given on the next succeeding business day), if sent via overnight
courier, on the business day next succeeding delivery to the courier, and if mailed by United States certified or registered mail, three (3) business days following such mailing in accordance with this Section. 

  
 17 

 18. Furniture. During the Term, at no charge to Subtenant, Subtenant shall be
permitted to use the existing furniture located in the Subleased Premises and described in more particular detail in Exhibit C attached hereto, as well as all equipment and data cabling associated therewith (the “Furniture”).
Subtenant shall accept the Furniture in its current condition without any warranty of fitness from Sublandlord (Subtenant expressly acknowledges that no warranty is made by Sublandlord with respect to the condition of any cabling currently located
in or serving the Subleased Premises). For purposes of documenting the current condition of the Furniture, Subtenant and Sublandlord shall, prior to the Commencement Date, conduct a joint walk-through of the Subleased Premises in order to inventory
items of damage or disrepair. Subtenant shall use the Furniture only for the purposes for which such Furniture is intended and shall be responsible for the proper maintenance, insurance, care and repair of the Furniture, at Subtenant’s sole
cost and expense, using maintenance contractors specified by Sublandlord. Subtenant shall not modify, reconfigure or relocate any of the Furniture except with the advance written permission of Sublandlord, and any work of modifying any Furniture
(including, without limitation, changing the configuration of, “breaking down” or reassembly of cubicles or other modular furniture) shall be performed at Subtenant’s sole cost using Sublandlord’s specified vendors or an
alternate vendor approved in writing by Sublandlord (such approval to be granted or withheld on Sublandlord’s good faith discretion, based upon Sublandlord’s assessment of factors which include, without limitation, whether the performance
by such vendor will void applicable warranties for such Furniture and whether such vendor is sufficiently experienced in the design of such Furniture). No item of Furniture shall be removed from the Subleased Premises without Sublandlord’s
prior written consent. Prior to or promptly following the expiration or earlier termination of the Sublease, Sublandlord and Subtenant shall conduct a joint walk-through of the Subleased Premises to catalog any items of damage, disrepair, misuse or
loss among the Furniture (reasonable wear and tear excepted), and Subtenant shall be responsible, at Subtenant’s sole cost and expense, for curing any such items (including, with respect to loss, replacing any lost item with a substantially
similar new item reasonably acceptable to Sublandlord). 
 19. Signage. Subtenant shall be entitled to Building-standard lobby
directory signage (to be initially installed at Sublandlord’s sole cost and expense, provided that any changes requested by Subtenant shall be at Subtenant’s sole cost and expense consistent with Landlord’s signage program). Any
Subtenant installed signage will be removed at the end of the Term at Subtenant’s sole cost. 
 20. Brokers. Subtenant
represents that it has dealt directly with and only with Newmark Knight Frank (“Subtenant’s Broker”), as a broker in connection with this Sublease. Sublandlord represents that it has dealt directly with and only with CRESA
(“Sublandlord’s Broker”), as a broker in connection with this Sublease. Sublandlord and Subtenant shall indemnify and hold each other harmless from all claims of any brokers other than Subtenant’s Broker and
Sublandlord’s Broker claiming to have represented Sublandlord or Subtenant in connection with this Sublease. Subtenant and Sublandlord agree that Subtenant’s Broker and Sublandlord’s Broker shall be paid commissions by Sublandlord in
connection with this Sublease pursuant to a separate agreement. 

  
 18 

 21. Complete Agreement. There are no representations, warranties, agreements,
arrangements or understandings, oral or written, between the parties or their representatives relating to the subject matter of this Sublease which are not fully expressed in this Sublease. This Sublease cannot be changed or terminated nor may any
of its provisions be waived orally or in any manner other than by a written agreement executed by both parties. 
 22.
Confidentiality. Sublandlord and Subtenant acknowledge that the content of this Sublease and any related documents (including, without limitation, the terms and conditions of the Master Lease) are confidential information. Sublandlord and
Subtenant shall keep such confidential information strictly confidential and shall not disclose such confidential information to any person or entity other than their respective financial, legal and space planning consultants, or their respective
directors, officers, employees, attorneys, or accountants, to potential sub-subtenants (in the case of Subtenant), to Landlord and Landlord’s lenders (in the case of Sublandlord) and to potential
assignees of the Master Lease or this Sublease, or to the extent that disclosure is mandated by applicable laws. Notwithstanding the foregoing, the restriction on disclosure described in this Section 21 will not apply with respect to
(i) information which is or becomes generally available to the public other than as a result of a disclosure by a party hereto, or (ii) the inclusion by either party of a reference to this Sublease and/or information regarding the rent
payable hereunder in such party’s financial statement(s) which are compiled in a normal course of such party’s business (and the subsequent submission of such financial statements to governmental authorities as required by applicable law
and/or potential investors). 
 23. Interpretation. Irrespective of the place of execution or performance, this Sublease shall be
governed by and construed in accordance with the laws of the Commonwealth of Massachusetts. If any provision of this Sublease or the application thereof to any person or circumstance shall, for any reason and to any extent, be invalid or
unenforceable, the remainder of this Sublease and the application of that provision to other persons or circumstances shall not be affected but rather shall be enforced to the extent permitted by law. The table of contents, captions, headings and
titles, if any, in this Sublease are solely for convenience of reference and shall not affect its interpretation. This Sublease shall be construed without regard to any presumption or other rule requiring construction against the party causing this
Sublease or any part thereof to be drafted. If any words or phrases in this Sublease shall have been stricken out or otherwise eliminated, whether or not any other words or phrases have been added, this Sublease shall be construed as if the words or
phrases so stricken out or otherwise eliminated were never included in this Sublease and no implication or inference shall be drawn from the fact that said words or phrases were so stricken out or otherwise eliminated. Each covenant, agreement,
obligation or other provision of this Sublease shall be deemed and construed as a separate and independent covenant of the party bound by, undertaking or making same, not dependent on any other provision of this Sublease unless otherwise expressly
provided. All terms and words used in this Sublease, regardless of the number or gender in which they are used, shall be deemed to include any other number and any other gender as the context may require. The word “person” as used in this
Sublease shall mean a natural person or persons, a partnership, a corporation or any other form of business or legal association or entity. 

24. USA Patriot Act Disclosures. Subtenant is currently in compliance with and shall at all times during the Term remain in compliance
with the regulations of the Office of Foreign Asset Control (“OFAC”) of the Department of the Treasury (including those named on OFAC’s Specially Designated and Blocked Persons List) and any statute, executive order (including
the September 24, 2001, Executive Order Blocking Property and Prohibiting Transactions with Persons Who Commit, Threaten to Commit, or Support Terrorism), or other governmental action relating thereto. 

  
 19 

 25. Counterparts. This Sublease may be executed in multiple counterparts, each of
which is deemed an original but which together constitute one and the same instrument. This Sublease shall be fully executed when each party whose signature is required has signed and delivered to each of the parties at least one counterpart, even
though no single counterpart contains the signatures of all of the parties hereto. This Sublease may be executed in so-called “pdf” format and each party has the right to rely upon a pdf counterpart
of this Sublease signed by the other party to the same extent as if such party had received an original counterpart. 
 26. Landlord
Consent, Notwithstanding anything to the contrary contained in this Sublease, this Sublease is subject to and contingent upon Landlord’s written consent to this Sublease in accordance with the Master Lease (the “Consent”),
which Sublandlord shall attempt to obtain with commercially reasonable diligence, at its sole cost and expense, by no later than January 22, 2018. Sublandlord acknowledges that Subtenant may decline to execute any proposed Consent, and at
Subtenant’s option, the Consent shall be deemed not to have been delivered, in which Landlord does not (1) conceptually consent (subject to final review and approval of the specific plans therefor) to the installation by Subtenant of
(x) Subtenant’s proposed security system as described in Section 5(d) above and (y) the Modular Offices in accordance with Section 14(b)(i) (2) approve of the Term of this Sublease as it may be extended in accordance
with Section 2(a) above and (3) inform Subtenant if the Modular Offices will need to be removed at the end of the Term of this Sublease. If a fully executed Consent is not delivered by Landlord, or is deemed not to have been delivered in
accordance with this Section 26 above (a “Deemed Consent Failure”), by January 31, 2018, then either party hereto will have the right to terminate this Sublease by providing written notice to the other any time prior to the
delivery by Landlord to Sublandlord and Subtenant of a fully executed Consent (provided, however, that Sublandlord’s ability to terminate this Sublease pursuant to the provisions of this sentence shall be conditioned upon Sublandlord having
used diligent good faith efforts to obtain the Consent from Landlord) and, upon such termination, this Sublease shall automatically become null and void and of no further force and effect and Sublandlord and Subtenant shall have no further
obligations or liabilities hereunder. Notwithstanding anything to the contrary contained herein, Sublandlord shall not have the right to terminate this Sublease in accordance with this Section 26 in the event of a Deemed Consent Failure. 

[Remainder of Page Intentionally Left Blank.] 

  
 20 

 IN WITNESS WHEREOF, the parties hereto hereby execute this Sublease as of the Effective
Date. 
  

			
	SUBLANDLORD:	 	TWITTER, INC.,
		 	a Delaware corporation

  

			
		
	By:	 	/s/ Ned Segal
	Print Name:	 	Ned Segal
	Title:	 	CFO

  

			
	SUBTENANT:	 	SOLID BIOSCIENCES, LLC,
		 	a Delaware limited liability company

  

			
		
	By:	 	/s/ Ilan Ganot
	Print Name:	 	Ilan Ganot
	Title:	 	CEO

  
 21 

 EXHIBIT A 

Subleased Premises 
  

 
 This plan represents a depiction of the location of the subject space but not a representation of the size or location of
specific improvements or features of such space (such as, by way of example, furniture doors and interior walls). 

  
 1 

 EXHIBIT B 

Commencement Date Agreement 
  

					
	Date	 	 	 	
			
	Subtenant	 	 Solid Biosciences, LLC 
	 	
	Address	 	 	 	
		 	 	 	
		 	 	 	

  

	Re:	Commencement Date Letter Agreement with respect to that certain Sublease dated as of                      ,
2018, by and between TWITTER, INC., a Delaware corporation, as Sublandlord, and SOLID BIOSCIENCES, LLC, a Delaware limited liability company, as Subtenant, for 15,877 rentable square feet on the 5th floor of the Building located at 141
Portland Street, Cambridge, Massachusetts. 

 Dear
                         : 

In accordance with the terms and conditions of the above referenced Sublease, Subtenant accepts possession of the Subleased Premises and
agrees: 
  

	 	1.	The Commencement Date is                     , 2018; 

 

	 	2.	The Rent Commencement Date is                      , 2018; and 

 

	 	3.	The Expiration Date is                     , 20    . 

Please acknowledge your acceptance of possession and agreement to the terms set forth above by signing this Commencement Letter in the space
provided and returning a fully executed counterpart (a scanned signature sent in PDF or similar format to                  @twitter.com will suffice) to my
attention. 
  

	
	Sincerely,
	
	   

	Sublandlord Authorized Signatory
	
	Agreed and Accepted:

  

			
	Subtenant:	 	SOLID BIOSCIENCES, LLC
		
	By:	 	[EXHIBIT — DO NOT SIGN]
	Name:	 	 
	Title:	 	 
	Date: 	 	 

  
 1 

 EXHIBIT C 

Furniture 

  
 1 

					
	 Furniture
	  	Quantity	 
	 OVERALL
	  			
	 Desk Chair
	  	 	130	 
	 Pedestal Filing Cabinet
	  	 	102	 
	 Credenza
	  	 	13	 
	 Grey Upholstered Chair
	  	 	26	 
	 Wood Cube Side Table
	  	 	2	 
	 High Top Table
	  	 	2	 
	 High Top Stool
	  	 	8	 
	 Height Adjustable Desk
	  	 	22	 
	 Metal Stool
	  	 	2	 
	 Mobile White Board (A)
	  	 	7	 
	 Wood Octagon Side Table
	  	 	4	 
	 Coat Rack
	  	 	3	 
	 Micro Kitchen Stool
	  	 	5	 
	 Puzzle Wood Cube
	  	 	2	 
	 Rectangle Wood Side Table
	  	 	2	 
	 Book Shelf
	  	 	1	 
	 Filing Cabinet
	  	 	1	 
	 Ping Pong Table
	  	 	1	 
	 Mobile White Board (B)
	  	 	1	 
	 Conference Room Side Table
	  	 	2	 
	 Round Conference Table (A)
	  	 	3	 
	 Conference Chair
	  	 	30	 
	 Round Conference Table (B)
	  	 	2	 
	 Board Room Table
	  	 	1	 
	 Board Room Chair
	  	 	12	 
	 Wood Credenza
	  	 	1	 
	 Upholstered Sofa
	  	 	1	 
	 Grey Conference Chair
	  	 	20	 
	 Long White table (A)
	  	 	1	 
	 Long White Table (B)
	  	 	1	 
	 Merchandiser Refrigerator
	  	 	1	 
	 Standard Refrigerator
	  	 	1	 
	 Kegerator
	  	 	1	 
	 Dishwasher
	  	 	1	 
	 Water/Ice Machine
	  	 	1	 
	 Microwave
	  	 	2	 
	 Shelving Wall Unit
	  	 	2	 
	 Free Standing Table
	  	 	1	 
	 TV Rack
	  	 	1	 
	 AV Rack
	  	 	2	 
	 Conf Large Credenza
	  	 	1	 

					
	 ITEMIZED
	  			
	 Conference Room 509
	  			
	 Wood Side Table
	  	 	1	 
	 Conference Room 506
	  			
	 Round Conference Table (A)
	  	 	1	 
	 Conference Chairs
	  	 	7	 
	 Conference Room 505
	  			
	 Round Conference Table (A)
	  	 	1	 
	 Conference Chairs
	  	 	7	 
	 Conference Room 522
	  			
	 Round Conference Table (B)
	  	 	1	 
	 Conference Chairs
	  	 	5	 
	 Conference Room 524
	  			
	 Board Room Table
	  	 	1	 
	 Board Room Chairs
	  	 	12	 
	 Wood Credenza
	  	 	1	 
	 Conference Room 527
	  			
	 Round Conference Table (A)
	  	 	1	 
	 Conference Chairs
	  	 	7	 
	 Conference Room 525
	  			
	 Conference Room 520
	  			
	 Wood Side Table
	  	 	1	 
	 Upholstered Sofa
	  	 	1	 
	 Conference Room 519
	  			
	 Round Conference Table (B)
	  	 	1	 
	 Conference Chairs
	  	 	4	 
	 Conference Room 518
	  			
	 Long White Table (A)
	  	 	1	 
	 Grey Conference Chairs
	  	 	10	 
	 Conference Room 514
	  			
	 Long White Table (B)
	  	 	1	 
	 Grey Conference Chairs
	  	 	10	 

			
	 Women’s Restroom
	 	
	 Shelving Wall Unit
	 	1
	 Men’s Restroom
	 	
	 Shelving Wall Unit
	 	1
	 Micro Kitchen 
	 	
	 Merchandiser Refrigerator
	 	1
	 Standard Refrigerator
	 	1
	 Kegerator 
	 	1
	 Dishwasher 
	 	1
	 Water/Ice Machine
	 	1
	 Microwave
	 	2
	 Micro Kitchen Stool 
	 	5
	 IT Help Desk
	 	
	 IDF/Lab Room
	 	

 

 
 Item Quantity Description Desk Chair 130 Pedestal Filing Cabinet 102 Credenza 15 Grey Upholstered Chair 26 

 

 
 Wood Cube Side Table 2 High Top Table 2 High Top Stool 8 Height adjustable Desk 22 AV Rack 2 

 

 
 Mobile White Board (A) 7 Wood Octagon Side Table 4 Coat Rack 4 Micro Kitchen Stool 5 Puzzle Wood Cube 2 Rectangle Wood Side Table 2

 

 
 Book Shelf 1 Filing Cabinet 1 Ping Pong Table 1 Mobile White Board (B) 1 Conference Room Side Table 2 

 

 
 Round Conference Table Conference (A) 3 Conference Chair 30 Round Conference Table(B) 2 Board Room Table 1 Board Room Chairs 12

 

 
 Wood Credenza 1 Upholstered Sofa 1 Grey Conference Chairs 20 Long White Table (A) 1 Long White Table (B) 1 Shelving Wall Unit 2

 

 
 Merchandiser Refrigerator 1 Standard Refrigerator 1 Kegerator 1 Dishwasher 1 Water/Ice Machine 1 

 

 
 Microwave 2 Free Standing Table 1 TV Stand 1 Conf. Rm Large Credenza 1 

 

 

 

 

 

 

 

 

 EXHIBIT D 

Master Lease 

[This is the complete version of the master lease as provided to the Registrant.] 

  
 1 

 LEASE AGREEMENT 

by and between 
 KENDALL
SQUARE ENTITY, INC. 
 as Landlord 

and 
 TWITTER, INC.

 as Tenant 

With respect to the property known as 

141 Portland Street, Cambridge, Massachusetts 

Dated as of 

September 10, 2013 

 TABLE OF CONTENTS 
  

							
	 SECTION 

	  	 	PAGE	 
	1.	  	PREMISES	  	 	1	 
	2.	  	LEASE TERM	  	 	1	 
	3.	  	FIXED RENT	  	 	1	 
	4.	  	ADDITIONAL RENT	  	 	2	 
	5.	  	LETTER OF CREDIT	  	 	2	 
	6.	  	USE OF PREMISES	  	 	4	 
	7.	  	CONDITION OF PREMISES	  	 	4	 
	8.	  	HAZARDOUS MATERIALS	  	 	4	 
	9.	  	INDEMNIFICATION	  	 	6	 
	10.	  	ALTERATIONS, ADDITIONS OR IMPROVEMENTS BY TENANT	  	 	6	 
	11.	  	COVENANTS OF LANDLORD	  	 	10	 
	12.	  	COVENANTS OF TENANT	  	 	12	 
	13.	  	ASSIGNMENT AND SUBLETTING	  	 	14	 
	14.	  	EMINENT DOMAIN	  	 	16	 
	15.	  	FIRE OR OTHER CASUALTY	  	 	16	 
	16.	  	INSURANCE; WAIVER OF SUBROGATION	  	 	17	 
	17.	  	INSPECTION; ACCESS; CHANGES IN BUILDING FACILITIES	  	 	19	 
	18.	  	DEFAULT	  	 	21	 
	19.	  	LANDLORD’S RIGHTS AND REMEDIES	  	 	21	 
	20.	  	LANDLORD’S RIGHT TO CURE TENANT’S DEFAULT	  	 	23	 
	21.	  	TENANT ESTOPPEL CERTIFICATE	  	 	23	 
	22.	  	SUBORDINATION, NON-DISTURBANCE AND ATTORNMENT AGREEMENT	  	 	23	 
	23.	  	FINANCIAL STATEMENTS. [INTENTIONALLY OMITTED]	  	 	24	 
	24.	  	HOLDING OVER	  	 	24	 
	25.	  	SURRENDER OF PREMISES	  	 	24	 
	26.	  	REMOVAL OF TELECOM WIRES	  	 	24	 
	27.	  	BROKERS	  	 	25	 
	28.	  	NOTICES	  	 	25	 
	29.    	  	MISCELLANEOUS	  	 	25	 
		  	 29.1      AUTHORITY
	  	 	25	 
		  	 29.2      SUCCESSORS AND ASSIGNS
	  	 	26	 

  
 -i- 

							
		  	 29.3      WAIVERS
	  	 	26	 
		  	 29.4      WAIVER OF TRIAL BY JURY
	  	 	26	 
		  	 29.5      LIMITATION OF LANDLORD’S LIABILITIES
	  	 	26	 
		  	 29.6      TIME OF THE ESSENCE
	  	 	26	 
		  	 29.7      SEVERABILITY
	  	 	26	 
		  	 29.8      HEADINGS AND TERMS
	  	 	26	 
		  	 29.9      LEASE NOT BINDING UNTIL EXECUTED AND DELIVERED
	  	 	27	 
		  	 29.10    COUNTERPARTS
	  	 	27	 
		  	 29.11    AMENDMENT AND MODIFICATION
	  	 	27	 
		  	 29.12    GOVERNING LAW
	  	 	27	 
	30.	  	PARKING	  	 	27	 
	31.	  	CONTINGENCY	  	 	27	 
	32.    	  	EXHIBITS AND ADDENDA	  	 	28	 
		  	 EXHIBIT “A” PREMISES
	  	 	A-l	 
		  	 EXHIBIT “B” FIXED RENT
	  	 	B-l	 
		  	 EXHIBIT “C” PROVISIONS REGARDING ADDITIONAL RENT
	  	 	C-l	 
		  	 EXHIBIT “D” BUILDING RULES AND REGULATIONS
	  	 	D-l	 
		  	EXHIBIT “E” FORM OF NON-DISTURBANCE, ATTORNMENT AND	  			
		  	 SUBORDINATION AGREEMENT
	  	 	E-l	 
		  	 EXHIBIT “F” EXTENSION OPTION
	  	 	F-l	 
		  	 EXHIBIT “G” BUILDING UPGRADES
	  	 	G-l	 
		  	 EXHIBIT “H” LEASE COMMENCEMENT DATE CERTIFICATE
	  	 	H-1	 
		  	 EXHIBIT “I” SATELLITE DISH TERMS AND CONDITIONS
	  	 	I-1	 

  
 -ii- 

 LEASE AGREEMENT 

THIS LEASE AGREEMENT (the “Lease”) is made and entered into as of this 10th day of September 2013 (the
“Effective Date”) by and between KENDALL SQUARE ENTITY, INC., a Massachusetts corporation (the “Landlord”), and TWITTER, INC., a Delaware corporation (the “Tenant”). 

Intending to be legally bound, Landlord and Tenant agree as set forth below. 

1. PREMISES. Landlord hereby leases to Tenant and Tenant hereby leases from Landlord, for the term and subject to and with the benefit of the
terms, covenants, conditions, agreements and provisions hereof space consisting of: (a) approximately 15,877 rentable square feet on the 5th floor (the “5th Floor Premises”), (b) approximately 15,877 rentable square feet on the 6th floor (the “6th Floor Premises”), and (c) approximately 15,877 rentable square feet on the 7th floor (the “7th Floor Premises”) as outlined on Exhibit “A” attached hereto and made part of hereof (collectively, 5th Floor
Premises, 6th Floor Premises and 7th Floor Premises shall be known as the “Premises”), in the building (the “Building”) erected on certain land (the “Land”) located at 141 Portland Street,
Massachusetts, together with rights of ingress and egress thereto, and with the right in common with others to use, to the extent applicable, the elevators and common passageways, stairways and vestibules, and to pass over and park on that portion
of land owned by Landlord and designated by Landlord for Tenant’s parking. For purposes of this Lease, the Premises shall be deemed to be approximately 47,631 rentable square feet and the Building shall be deemed to be 135,874 rentable square
feet. The parties acknowledge and accept the rentable square feet as set forth in this Lease and shall not have the right to re-measure or recalculate the rentable square feet with respect to the Premises or
the Building. 
 2. LEASE TERM. 
 2.1
Generally. Subject to the terms and conditions contained herein, including but not limited to Section 31, the lease term (the “Lease Term”) shall commence on the date (the “Lease Commencement Date”) upon
which the: (a) 7th Floor Premises is delivered by Landlord to Tenant in its “as-is” condition; and (b) the 5th Floor Premises and 6th Floor Premises is delivered by Landlord to Tenant in “Shell Condition”, defined below (collectively, the
“Delivery Condition” and such delivery being referred to as “Delivery”) which is estimated to be October 1, 2013 (the “Target Commencement Date”) and shall expire on the last day of the full
sixty-sixth (66th) month after the Lease Commencement Date (defined in Section 3.1 below), unless extended or terminated as provided in this Lease (the “Expiration Date”). Upon the Lease Commencement Date, Landlord and Tenant
shall enter into a Lease Commencement Date certificate in the form attached hereto as Exhibit “H” in order to confirm the Lease Term and schedule with respect to fixed rent. For purposes herein, “Shell Condition”
shall mean that all existing floor covering, partitions and ceiling has been removed from the Premises. 
 3. FIXED RENT. 

3.1 Fixed Rent. Except as otherwise set forth herein, Tenant shall pay fixed rent (the “Fixed Rent”) beginning on the
Lease Commencement Date in monthly installments in accordance with the schedule set forth on Exhibit “B” attached hereto and made a part hereof, without prior notice or demand, and without any setoff or deduction whatsoever (except
as expressly set forth herein), in advance, on the first day of each month at such place as Landlord may direct in writing. If the Lease Term shall commence or expire on other than the first or last day, as applicable, of a calendar month, such
monthly installment of Fixed Rent and any applicable Additional Rent, as set forth below, shall be prorated for each calendar day of such partial month. 

  
 -1- 

 3.2 Late Payment. If any portion of Fixed Rent, Additional Rent or any other sum
payable to Landlord hereunder shall be due and unpaid for more than five (5) days after its due date, it shall bear interest at a rate equal to ten percent (10%) (the “Default Rate”) from the due date until the date of payment
thereof by Tenant. In addition Tenant shall pay a late charge equal to five percent (5%) of the late payment; provided, however, that Tenant shall be entitled to written notice of non-payment and a five
(5) day grace period prior to the imposition of such late charge on the first (1st) occasion in any calendar year in which any installment of Rent is not timely paid. If any payment tendered by Tenant shall fail collection on presentment,
Tenant shall reimburse Landlord for all charges imposed by Landlord’s bank on account thereof and pay to Landlord a bad check fee equal to the lesser of (a) $100.00 or (b) the maximum charge permitted by law. In no event shall Landlord be
deemed to contract for or receive charges by way of interest or otherwise in excess of those permitted by law and any sum paid in excess of that permitted shall be refunded or credited to Tenant. 

3.3 Demolition Credit. In consideration of Tenant accepting possession of the 7th
Floor Premises in its “as-is” condition and Landlord not removing the existing floor covering, partitions and ceiling in the 7th Floor Premises,
Landlord shall provide Tenant with a credit toward Fixed Rent, to be applied after the determination of the amount of the credit, as follows: once Landlord has completed the demolition of the 5th
Floor Premises and the 6th Floor Premises individually, Landlord shall calculate the average costs incurred by Landlord in completing such demolition work, on a “per rentable square
foot” basis, and deliver a statement (together with reasonably detailed back up documentation) setting forth costs; Tenant’s credit for the 7th Floor Premises shall be equal to the costs
incurred by Landlord in performing such demolition work. 
 4. ADDITIONAL RENT. In addition to Fixed Rent, and as more fully set forth
on Exhibit “C” attached hereto and made a part hereof, Tenant shall pay to Landlord for each month of each calendar year of the Lease Term following the Base Year or Base Tax Year, as applicable, described in Exhibit
“C”, without demand (except for such notice as is described in Exhibit “C”), deduction or setoff, as “Additional Rent” (which amounts along with any other amounts or charges which may become due
or payable by tenant to landlord may collectively or separately be referred to as “Rent” hereunder): (a) Tenant’s Proportionate Share of Operating Expenses to the extent the Operating Expenses exceed the Operating Expense Stop;
and (b) Taxes (on a per rentable square foot basis) to the extent the Taxes exceed the Tax Expense Stop (as such terms are defined in Exhibit “C”). 

5. LETTER OF CREDIT. 
 [*] 

  
 - 2 - 

 [*] 

  
 - 3 - 

 6. USE OF PREMISES. Tenant covenants and agrees to use and occupy the Premises for general
office use purposes (which will be deemed to include the use and operation of a “warming” kitchen and occasional receptions and/or gatherings for Tenant’s employees, clients and consultants) as permitted by law and for no other
purpose without the prior written consent of Landlord (the “Permitted Use”). Tenant shall not use or permit any use of the Premises which creates any safety or environmental hazard, or which would: (a) be dangerous to the
Premises, the Building or other tenants of the Building, or (b) unreasonably disturb other tenants of the Building, or (c) cause any increase in the premium cost for any insurance which Landlord may then have in effect with respect the
Building generally. Landlord makes no representation or warranty that the Premises are fit for the Permitted Use. In addition, Tenant shall be responsible, at its sole cost and expense for obtaining any and all applicable permits necessary to
construct the Initial Improvements and to legally occupy the Premises for the Permitted Use, including but not limited to the certificate of occupancy if necessary. Except when and where Tenant’s right of access is specifically prevented as a
result of (i) an emergency, (ii) a requirement by law, or (iii) a specific provision set forth in this Lease, Tenant shall have the right of ingress and egress to the Premises, the building, and the parking areas twenty-four
(24) hours per day, seven (7) days per week. 
 7. CONDITION OF PREMISES. 

7.1 Taking possession of the Premises by Tenant shall be deemed to establish a rebuttable presumption that the Premises are in good and
satisfactory condition as of the Lease Commencement Date, subject to Landlord’s express representations and maintenance/repair obligations set forth herein. Tenant acknowledges that except as set forth herein to the contrary, no representations
as to the condition of the Premises have been made by Landlord. Except for the Delivery Condition as described in Section 2.1, Tenant acknowledges and agrees that Landlord shall deliver and Tenant shall accept the Premises in Delivery Condition and
Landlord shall not be responsible for performing any other work in the Premises in order to prepare the Premises for Tenant’s occupancy (other than such work as may be necessary to bring the Building Systems into good working order and repair).

 7.2 Landlord represents that: 

(a) As of the Lease Commencement Date, to the best of its actual knowledge, without due inquiry, Landlord has not received any notice that the
Building and Premises are in violation of any applicable laws, including without limitation, the Americans with Disabilities Act; and 
 (b)
As of the Lease Commencement Date, it shall deliver in good working order and condition all base Building finishes, systems, and structures (including, but not limited to, all Building Systems). Tenant will have thirty (30) days after
Landlord’s delivery of the Premises in which to notify Landlord and to the extent that any components of the Building Systems are not in good working order and repair, in such event, Landlord will promptly repair or replace the items of the
Building Systems as necessary so that the same are in good working order. 
 8. HAZARDOUS MATERIALS. 

8.1 Limitations on Use. Tenant shall not transport, use, store, maintain, handle, generate, manufacture, dispose, discharge or release
any Hazardous Material (as defined below in Section 8.2) upon or about the Premises, or permit Tenant Responsible Parties (as defined below in Section 8.2) to engage in such activities upon or about the Property in violation of applicable
laws and regulations. However, the foregoing provisions shall not prohibit the transportation to and from, and use, storage, maintenance and handling within the Premises of Hazardous Materials customarily used in the business or activity expressly
permitted to be undertaken in the Premises under this Lease; provided: (a) such substances 

  
 - 4 - 

 
shall be used and maintained only in such quantities as are reasonably necessary for such permitted use of the Premises and the ordinary course of Tenant’s business therein, strictly in
accordance with all applicable laws, prevailing standards and the manufacturers’ instructions therefor, (b) such substances shall not be disposed of, discharged or released in or about the Premises (except as may be permitted by applicable
law), and shall be transported to and from the Premises in compliance with all applicable laws, (c) if any applicable law or Landlord’s trash removal contractor requires that any such substances be disposed of separately from ordinary
trash, Tenant shall make arrangements at Tenant’s expense for such disposal directly with a qualified and licensed disposal company at a lawful disposal site (subject to scheduling and approval by Landlord), (d) any remaining such substances
shall be completely, properly and lawfully removed from the Property upon expiration or earlier termination of this Lease, and (e) for purposes of removal and disposal of any such substances for which applicable law requires such a classification,
Tenant shall be named as the owner and generator, obtain a waste generator identification number, and execute all applications, permits, manifests, waste characterization documents and any other required forms. As of the Commencement Date, without
due inquiry, Landlord hereby represents to Tenant that Landlord has not received any notice that the Building is in violation of any federal, state and local laws, ordinances, regulations, orders and directives pertaining to Hazardous Materials,
Landlord will indemnify, defend, protect and hold harmless and defend Tenant from and against any and all loss, cost, damage, or liability arising out of the presence on or about the Building of any Hazardous Materials, or any releases or discharges
of any Hazardous Materials on, under or from the Building attributable to Landlord or Landlord’s employees, contractors, representatives or agents. 

8.2 Notices Regarding Hazardous Materials. Tenant shall immediately notify Landlord in writing of: (a) any enforcement, cleanup or
other regulatory action taken or threatened by any governmental or regulatory authority with respect to the presence of any Hazardous Material on the Premises or the migration thereof from or to other property, to the extent caused by Tenant or its
operation in the Premises, (b) any demands or claims made or threatened by any party relating to any loss or injury resulting from any Hazardous Material placed or introduced into the Premises by Tenant, (c) any discharge, release or non-routine, improper or unlawful disposal or transportation by Tenant of any Hazardous Material on or from the Premises or in violation of this Section 8, and (d) any matters where Tenant is required by
law to give a notice to any governmental or regulatory authority respecting any Hazardous Material on the Premises. Landlord shall have the right (but not the obligation) to join and participate, as a party, in any legal proceedings or actions
affecting the Premises initiated in connection with any environmental, health or safety law. At such times as Landlord may reasonably request, Tenant shall provide Landlord with a written list, certified to be true and complete, identifying any
Hazardous Material then used, stored, or maintained upon the Premises, the use and approximate quantity of each such material, a copy of any material safety data sheet (the “MSDS”) issued by the manufacturer or supplier therefore,
and such other information as Landlord may reasonably require or as may be required by law. The term “Hazardous Material” for purposes hereof shall mean any chemical, substance, material or waste or component thereof which is now or
hereafter listed, defined or regulated as a hazardous or toxic chemical, substance, material or waste or component thereof by any federal, state or local governing or regulatory body having jurisdiction, or which would trigger any employee or
community “right-to-know” requirements adopted by any such body, or for which any such body has adopted any requirements for the preparation or distribution of
an MSDS. 
 8.3 Remediation. If any Hazardous Material is released, discharged or disposed of by Tenant or Tenant Responsible
Parties, on or about the Property in violation of Section 8, Tenant shall immediately, properly and in compliance with all applicable laws clean up and remove the Hazardous Material from the Property and any other affected property and clean or
replace any affected personal property (whether or not owned by Landlord), at Tenant’s expense (without limiting Landlord’s other remedies therefore). Such clean up and removal work shall be subject to Landlord’s prior written

  
 - 5 - 

 approval (except in emergencies), which shall not be unreasonably withheld, delayed or conditioned, and
shall include, without limitation, any testing, investigation, and the preparation and implementation of any remedial action plan required by any court or governmental body having jurisdiction or reasonably required by Landlord. If Landlord or any
lender or governmental body arranges for any tests or studies showing that Section 8 has been violated by Tenant, Tenant shall pay for the actual costs of such tests, Nothing in Section 8 shall be construed as preventing Tenant from
obtaining additional testing at its own expense. During the Lease Term, Landlord shall have the option, at Landlord’s sole cost (except as set forth above) to retain a consultant who will conduct an investigation to verify that no portion of
the Building (including the Premises, to the extent Landlord has reasonable cause to believe that there is such a use) is being used for any activities involving, directly or indirectly, the unlawful use, storage, maintenance, handling, generation,
manufacture, disposal, discharge or release of any Hazardous Material. Subject to terms and conditions of this Lease regarding Landlord’s access, Tenant hereby grants to Landlord, its agents, employees, consultants and contractors the right to
enter upon the Premises and to perform such tests on the Premises as are reasonably necessary to conduct any such investigation, To the extent Tenant discovers any Hazardous Materials at the Premises, which was not introduced to or released in the
Premises by Tenant by any action or inaction, or its agents, employees or contractors, and the presence of which violates any applicable laws, regulations or other requirements now or hereafter in effect, then Landlord shall, at its sole cost,
comply with all such laws, regulations or other requirements with respect to the remediation of the same. 
 8.4 Tenant’s
Indemnity. Tenant covenants and agrees to exonerate, indemnify, defend, protect and save Landlord and Landlord Parties (as defined herein) harmless from and against all claims, demands, expenses, losses, suits and damages in connection with the
presence or use of any Hazardous Materials on the Property caused by Tenant or its agents. The obligations of Tenant hereunder shall survive expiration or earlier termination of this Lease. 

9. INDEMNIFICATION. 
 9.1 By
Tenant. Except for the gross negligence or willful misconduct of Landlord or any Landlord Party, and subject to the terms of Section 16.3 below, Tenant covenants and agrees to exonerate, indemnify, defend, protect and save Landlord,
Landlord’s managing agent and Landlord’s mortgagee (if any) (the “Landlord Parties”) harmless from and against any and all claims, demands, expenses, losses, suits and damages’ as may be occasioned by reason of
(i) any accident, injury or damage occurring in or about the Premises causing injury to persons or damage to property (including, without limitation, the Premises); and (ii) the failure of Tenant to fully and faithfully perform the
obligations and observe the conditions of this Lease. 
 9.2 By Landlord. Except for the gross negligence or willful misconduct of
Tenant or any Tenant Party, and subject to the terms of Section 16.3 below, Landlord hereby covenants and agrees to exonerate, indemnify, defend, protect and save Tenant harmless on account of damage to the person or property of any party
occurring outside of the Premises, including any other tenant in the Building, to the extent caused by the negligence or breach of this Lease by the Landlord, Landlord’s agents or any Landlord party. 

10. ALTERATIONS, ADDITIONS OR IMPROVEMENTS BY TENANT. 

10.1 Alterations by Tenant. Tenant shall not make any alterations, additions, improvements or other changes in or to the Premises (the
“Alterations”), other than the installation of typical office decorations, furniture and furnishings which are not affixed to the realty, without Landlord’s prior written consent (such consent not to be unreasonably withheld,
conditioned or delayed). Landlord’s consent shall 

  
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not be required for any Alteration that satisfies all of the following criteria: (1) is not visible from the exterior of the Premises or Building; (2) is of a cosmetic nature such as
painting, wallpapering, hanging pictures and installing carpeting, or costs less than $50,000 for any one project; (3) does not require work to be performed inside the demising walls or above the ceiling of the Premises; and (4) Tenant
secures Lien Waivers (as defined below) with respect to such Alterations. If any proposed Alterations will adversely affect the exterior or structural components of the Building, or the Building Systems, Landlord may withhold its consent to such
Alterations in Landlord’s sole discretion. Without limitation, it shall not be unreasonable for Landlord to withhold its consent to any Alterations which would impose on Landlord any special maintenance, repair or replacement obligations not
within the scope of those expressly provided for herein, unless Tenant agrees, at the time of its request for approval or notice of such Alterations, to pay all costs associated with Landlord’s meeting the additional obligations. Landlord
agrees to respond to any request by Tenant for approval of Alterations for which approval is required hereunder within ten (10) business days after delivery of Tenant’s written request; Landlord’s response shall be in writing and, if
Landlord withholds its consent to any Alterations, Landlord shall specify in reasonable detail in Landlord’s notice of disapproval, the basis for such disapproval, and the changes to Tenant’s plans which would be required in order to
obtain Landlord’s approval. If Landlord fails to notify Tenant of Landlord’s approval or disapproval within such ten (10) business day period, Tenant shall have the right to provide Landlord with a second written request for approval
(a “Second Request”) that specifically identifies the applicable plans and contains the following statement in bold and capital letters: “THIS IS A SECOND REQUEST FOR APPROVAL PURSUANT TO THE PROVISIONS OF SECTION 10.1 OF
THE LEASE. IF LANDLORD FAILS TO RESPOND “WITHIN FIVE (5) BUSINESS DAYS AFTER RECEIPT OF THIS NOTICE, THEN LANDLORD SHALL BE DEEMED TO HAVE APPROVED THE WORK DESCRIBED HEREIN.” If Landlord fails to respond to such Second
Request within five (5) business days after receipt by Landlord, the work in question shall be deemed approved by Landlord. If Landlord timely delivers to Tenant notice of Landlord’s disapproval, Tenant may revise Tenant’s plans to
incorporate the changes suggested by Landlord in Landlord’s notice of disapproval, and resubmit such plans to Landlord; in such event, the scope of Landlord’s review of such plans shall be limited to Tenant’s correction of the items
in which Landlord had previously objected in writing. Landlord’s review and approval (or deemed approval) of such revised plans shall be governed by the provisions set forth above in this Section 10.1). The procedure set out above for
approval of Tenant’s plans will also apply to any change, addition or amendment to Tenant’s plans. Subject to Section 10.5 below, prior to the expiration or earlier termination of this Lease, and without additional notice to Tenant by
Landlord, Tenant shall remove any such Alterations and repair any damage to the Premises or the Building occasioned by their installation or removal so as to restore the Premises to substantially the same condition as existed prior to the time when
any such Alterations were made. All Alterations shall be subject to the provisions of Sections 10.2, 10.3 and 10.4 below. 
 10.2 Quality
and Performance of Work. All construction work required or permitted by this Lease shall be done in a good and workmanlike manner by licensed union contractors approved by Landlord (such approval not to be unreasonably withhold, conditioned or
delayed) and in compliance with the Building Rules and Regulations, attached hereto as Exhibit “E”, all insurance requirements of this Lease, and all applicable laws, statutes, codes, ordinances, orders, rules, regulations,
conditions of approval and requirements of all federal, state, county, municipal and other governmental authorities, including the requirements of the Americans with Disabilities Act (“ADA”) (collectively, “Legal
Requirements”). 

  
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 10.3 Additional Covenants Regarding Alterations. 

(a) All Alterations and Initial Tenant Improvements (as defined herein) shall be made (i) at Tenant’s sole cost and expense,
(ii) according to plans and specifications approved in writing by Landlord which approval shall not be unreasonably withheld, conditioned or delayed (iii) in compliance with all Legal Requirements, (iv) by a licensed union contractor,
and (v) in a good and workmanlike manner. Tenant shall provide Landlord with as-built plans for any Alterations for which plans are used, regardless of whether the Alterations require Landlord’s
consent hereunder. 
 (b) Tenant shall keep the Premises and the Building free from any liens arising out of any work performed, materials
ordered or obligations incurred by or on behalf of Tenant. Without limitation, Tenant shall be responsible for, and shall pay when due, all costs associated with the preparation of plans and the performance of Alterations and the same shall be
performed in a lien-free, good and workmanlike manner, and in compliance with all Legal Requirements. In the event that Tenant shall fail to pay the costs associated with Alterations on a timely basis, and as a result of such failure, a statutory
and/or common law lien is asserted against the Premises or the Building, and Tenant shall fail, within fifteen (15) days after notice of such assertion, to cause (by payment, posting of a proper bond, or otherwise) such lien to be released of
record, Landlord shall have the right (but not the obligation), at Tenant’s expense, to cause such lien to be bonded over or released of record. 

(c) Tenant shall ensure that all contractors and subcontractors performing Alterations are insured in amounts required by law. If Landlord
requests, certificates of such insurance shall be delivered to Landlord. Tenant’s obligation to exonerate, indemnify, defend, protect and save Landlord Parties harmless, as set forth in Section 8, shall include without limitation all
activities and work done by and on behalf of Tenant pursuant to this Section 9 and shall commence on the date of execution hereof. 

(d) Tenant agrees that Landlord shall have the right to examine and inspect any Alterations; provided, however, that no such examination or
inspection shall constitute an approval or warranty or give rise to any liability of Landlord with respect to any thereof. In the performance of Alterations in accordance with this Lease, Tenant shall cause its contractors to use reasonable and
diligent efforts not to interfere with ongoing operations on the rest of the Building, to keep all construction areas clean and free of trash and debris, and otherwise to comply with any other reasonable rules and regulations established by Landlord
with regard to construction activities. 
 (e) Tenant shall provide copies of any warranties for Alterations and the materials and equipment
which are incorporated into the Premises and the Building in connection therewith, and either assign to Landlord, or enforce on Landlord’s behalf, all such warranties to the extent repairs and/or maintenance on warranted items would be covered
by such warranties and are otherwise Landlord’s responsibility under this Lease. 
 (f) Landlord shall not have the right to charge any
construction administration or supervision fee in connection with Tenant’s performance of Alterations; provided that Tenant will reimburse Landlord for any third party costs actually incurred by Landlord in the review of Tenant’s plans.

 10.4 Removal of Specialty Alterations. Landlord shall notify Tenant in writing at the time of Landlord’s approval of any
Alterations whether any such Alterations constitute Specialty Alterations (defined below), and, in such event, if such Specialty Alterations will be required to be removed by Tenant at the end of the Lease Term (Landlord will not have the right to
require that any Initial Alterations (defined in Section 10.5 below) be removed by Tenant); if Landlord fails to provide such 

  
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notice at the time of Landlord’s approval, Landlord shall be deemed to have waived the right to require the removal of the Specialty Alteration in question. As used herein,
“Specialty Alterations” shall mean Alterations that (i) perforate, penetrate or require reinforcement of a floor slab (including, without limitation, interior stairwells or high-density filing or racking systems), (ii) consist
of the installation of a raised flooring system, (iii) consist of the installation of a vault or other similar device or system intended to secure the Premises or a portion thereof in a manner that exceeds the level of security necessary for
ordinary office space, (iv) involve material plumbing connections (such as, for example but not by way of limitation, kitchens, saunas, showers, and executive bathrooms outside of the Building core and/or special fire safety systems), (v)
consist of the dedication of any material portion of the Premises to non-office usage (such as classrooms). 

10.5 Improvement Allowance. As an inducement to Tenant’s entering into this Lease, Landlord shall provide to Tenant an allowance
of [*] per rentable square foot of the Premises (i.e., a maximum of [*] based on 47,631 rentable square feet) (the “Improvement Allowance”) to be used by Tenant solely toward the costs associated with design, permitting and
construction of the initial build-out of the Premises (the “Initial Improvements”), including project management, fees and construction consultant. In addition, Landlord shall provide
Tenant with an allowance of up to $[*] per rentable square foot of the Premises (i.e. a maximum of $[*] based on 47,631 rentable square feet) to be used by Tenant solely toward the costs of all test fits for the Premises (the “Test Fit
Allowance”). Tenant shall have the option to (a) use its own union general contractor, reasonably approved by Landlord, to perform the Initial Improvements pursuant to Section 10.6 below; or (b) designate Landlord to perform
the Initial Improvements pursuant to Section 10.7 below. 
 10.6 Tenant Performance of Initial Improvements. The Initial
Improvements shall be; (a) performed by Tenant; (b) subject to the provisions of Sections 10.2, 10.3 and 10.4 above; (c) performed by a union general contractor reasonably approved by Landlord; and (d) based on plans and
specifications reasonably approved by Landlord (the “Initial Improvement Plans”), the approval of which will be governed by Paragraph 10.1 above; and (d) the following terms and conditions shall apply: 

(i) Landlord shall pay Landlord’s Proportion (as hereinafter defined) of the cost shown on each requisition (as hereinafter defined)
submitted by Tenant to Landlord within thirty (30) days of submission thereof until the entirety of the Improvement Allowance has been exhausted. “Landlord’s Proportion” shall be a fraction, the numerator of which is the
Improvement Allowance, and the denominator of which is the total cost the Initial Improvements. A “requisition” shall mean written documentation, including, without limitation, (i) invoices from Tenant’s contractors,
vendors, service providers and consultants, and such other documentation as Landlord may reasonably request, showing in reasonable detail the cost of the items in question or improvements installed to date in the Premises, accompanied by
certifications from Tenant that the amount of the requisition in question is true and correct and does not exceed the cost of the items or improvements covered by such requisition (AIA Form G-702 is deemed
acceptable by Landlord as a requisition form); and (ii) evidence that all of the Initial Improvements and other work done by or on behalf of Tenant as of such date which could give rise to any mechanic’s or materialman’s liens and for
which payment has been previously requested and paid, has been paid for in full and that any and all liens therefor that, have been or may be filed have been satisfied of record or waived (the “Lien Waivers”) with respect to the
prior month’s requisition. Landlord shall have the right, upon reasonable advance notice to Tenant, to inspect Tenant’s books and records relating to each requisition in order to verify the amount thereof. 

  
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 (ii) Tenant shall not submit requisitions, nor shall Landlord have any obligation to advance
funds on account of the Improvement Allowance, more often than once per month. 
 (iii) If Tenant fails to pay the amounts paid by Landlord
to Tenant in the prior month’s requisition to Tenant’s contractors, vendors, service providers and consultants, Landlord shall thereafter have the right to have the Improvement Allowance paid directly to Tenant’s contractors, vendors,
service providers and consultants. 
 (iv) In no event shall the Improvement Allowance be applied to any fees paid to Tenant. 

(v) Landlord shall have no obligation to pay any portion of the Improvement Allowance with respect to any requisition submitted twelve
(12) months after the Lease Commencement Date (the “Outside Requisition Date”); provided, however, that if Tenant certifies to Landlord that it is engaged in a good faith dispute with a contractor, vendor, service provider or
consultant, such Outside Requisition Date shall be extended while such dispute is ongoing, so long as Tenant is diligently pursuing the resolution of such dispute. Tenant shall not be entitled to receive any portion of the Improvement Allowance
except to the extent that it has submitted requisitions, and/or made demand therefor, on or before the Outside Requisition Date. In the event Tenant has not utilized the Improvement Allowance on or before the Outside Requisition Date, Tenant shall
be deemed to have forfeited any unused portion of said Improvement Allowance and shall have no rights thereto. 
 (vi) In addition to all
other requirements hereof, Landlord’s obligation to pay the final requisition of the Improvement Allowance shall be subject to simultaneous delivery of all Lien Waivers in connection with the Initial Improvements. 

(vii) Tenant acknowledges that any Alterations and the Initial Improvements must be completed using union labor and it shall not take any
action which would cause a work stoppage, picketing, labor disruption or dispute (the “Labor Disruption”). Accordingly, Tenant acknowledges that Tenant shall, at its sole cost and expense, take any and all actions reasonably
necessary to resolve any Labor Disruption that may arise as a result of Tenant’s violation of the requirement that Tenant use union labor. 

(viii) Tenant acknowledges that if any of the Alterations or Initial Improvements must be completed beyond normal construction hours (Monday
through Friday between the hours of 7:30am to 3:30pm)(the “Construction Hours”), Tenant shall pay to Landlord for cost of Landlord’s on-site supervisory personnel at the rate of $75.00
per hour within thirty (30) days of invoice from Landlord. 
 10.7 Permits. Tenant shall deliver to Landlord a copy of the final
application for permit and issued permit for the construction of the Initial Improvements prior to commencement of construction. Landlord, at no additional cost to Landlord, will use reasonable efforts to cooperate with Tenant in Tenant’s
efforts to procure applicable construction permits. 
 11. COVENANTS OF LANDLORD. 

11.1 Landlord shall be responsible for maintaining the structure, foundation, exterior and roof of the Building in good order and repair
throughout the Lease Term and for maintaining the building systems, including but not limited to the HVAC, electrical, mechanical (including elevator) life safety and plumbing systems which serve more than just the Premises as well as associated
transformers, duet work, cable, wires, and other equipment, facilities, and systems (the “Building Systems”) and all common areas in first-class order and repair, except that Landlord shall have no responsibility with respect to any
obligation hereinabove stated if caused by Tenant’s negligence. Subject to the provisions of Section 4 and Exhibits “C” and “D”, the cost of Landlord’s performance of such maintenance and
repair 

  
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responsibilities will be reimbursed by Building tenants as Operating Expenses to the extent applicable. Landlord is not responsible for maintenance and replacement of any such equipment, fixtures
or mechanical installations which are installed by or on behalf of Tenant and exclusively serve the Premises. As of the Effective Date, Landlord hereby represents that the Building Systems and Building roof are in good working order and condition.

 11.2 Each of Tenant’s employees will be issued a building pass to gain access to the Building and Premises 24 hours/day, 7
days/week. Tenant shall deposit with Landlord $25.00 for each pass which amount shall be returned to Tenant upon return of the pass in the same condition, reasonable wear and tear excepted. 

11.3 Landlord shall provide elevator facilities during regular business hours (8:00 a.m. to 6:00 p.m. Monday through Friday) on business days
(Saturdays, Sundays and Holidays are to be excepted) (the “Normal Business Hours”) and at all other times Landlord agrees to provide limited automatic elevator service to the Premises. Notwithstanding the foregoing, Landlord shall
not be responsible for any security relating to the elevator or Premises beyond Normal Business Hours and Tenant shall be obligated to provide its own security relating to the elevator and/or Premises beyond Normal Business Hours. In connection
therewith, Tenant may install its own security system in the Premises which will not interfere with the operation of Landlord’s security system serving the Building. 

11.4 Landlord shall provide heat, ventilation and air-conditioning (“HVAC”) for the
Premises, the main lobby, elevators, washrooms and stairs, during Normal Business Hours sufficient to maintain the a comfortable temperature range in the Building. Landlord shall provide heat or
air-conditioning at all other hours upon at least twenty-four (24) hours’ advance telephonic request from Tenant to the Building’s management office and at no additional cost. Alternatively, in
the event Landlord installs an energy management system at the Building, Tenant will be responsible for paying, within thirty (30) days following delivery of an invoice from Landlord, for the out-of-pocket cost for each hour of HVAC used beyond Normal Business Hours which shall be the cost incurred for increasing or decreasing the temperature, as the case may be, from the temperature at which the
Building is maintained under normal circumstances during Normal Business Hours to the temperature requested by Tenant. 
 11.5 Landlord
shall provide hot and cold running water to the Premises to the extent that the same is necessary to operate a kitchenette in the Premises. 

11.6 Landlord shall provide cleaning of the Premises, lobby, elevators, public corridors, washrooms and stairs, and removal of the
Tenant’s trash, daily, on business days (Monday through Friday) (Saturdays, Sundays, and Holidays excepted), provided the Premises are kept in good order by the Tenant. Said janitorial services will be commensurate with the level of services
provided in Comparable Buildings (defined below). Landlord shall not be responsible for the removal of, and Tenant shall, at its own expense, remove Tenant’s trash resulting from receptions, lunches, dinners, cocktail parties, or similar
functions, whether or not catered. 
 11.7 Landlord shall provide hot and cold running water, liquid soap, toilet tissue and paper towels
for the washrooms and lavatories serving the Premises. 
 11.8 Landlord shall provide electricity for normal lighting of the main lobby,
elevators, washrooms and stairs and Landlord shall provide electricity for normal lighting to the Premises. 
 11.9. Landlord shall provide
reasonable shoveling of snow and sanding of ice at the entries to the Building, commensurate with similar services provided in Comparable Buildings. 

  
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 11.10 Landlord shall provide adequate lighting of the parking area including the supplying
of all required fixtures and light bulbs, tubes and similar devices. 
 11.11 Landlord shall provide use of the loading dock and freight
elevator Monday through Friday, 7:00AM—3:00PM (excluding holidays), which is located on the Davis Street side of the Building in common with others who may be granted similar rights. 

11.12 Landlord is under no responsibility or liability for failure or interruption in such service caused by breakage, accident, strikes,
repairs, failure of fuel supply, inability by exercise of reasonable diligence to obtain fuel, electricity, supplies or other services or for any other cause or causes beyond the reasonable control of Landlord, nor in any event for any indirect or
consequential damages; and failure or omission on the part of Landlord for the foregoing reasons to furnish such service shall not be construed as an eviction of Tenant, nor work as an abatement of rent, nor render Landlord liable in damages, nor
release Tenant from prompt fulfillment of any of the covenants under this Lease, except that, if Landlord does not provide HVAC or electricity to the Premises for five (5) consecutive days (the “Eligibility Period”), there
shall be an abatement of Rent on a per diem basis for every consecutive day thereafter until such service is restored. 
 11.13
“Comparable Buildings” shall mean other similar office buildings in the Kendall Square/East Cambridge submarket of Cambridge, Massachusetts of comparable class, size, age and location not owned by Landlord or its affiliates. 

12. COVENANTS OF TENANT. 

Tenant, at Tenant’s sole cost and expense, will: 

12.1 Keep the Premises in good order and repair, reasonable wear and tear excepted; 

12.2 Surrender the Premises at the end of this Lease in the same condition in which Tenant has agreed to keep it during the Lease Term; 

12.3 Not place, erect, maintain or display any sign or other marking of any kind whatsoever on the windows, the exterior of the doors or on
the exterior walls of the Premises and not place any blinds, curtains, drapes or coverings over the exterior windows or on the window surfaces which are visible from the outside of the Building. The foregoing notwithstanding, Landlord hereby
consents to Tenant, at its sole cost and expense, and subject to Landlord’s prior written approval which shall not be unreasonably withheld, installing and maintaining its own custom signage at the entrance to the Premises on each floor on
which the Premises is located (not intending to mean the entrance to the Building). In addition, Landlord agrees to provide, at its sole cost and expense, and subject to all applicable regulations, Tenant’s signage in the first floor lobby
directory, the style and quality of which shall be consistent with other of such signage within the Building. After the initial installation of the signage in the first floor lobby directory, any changes to such signage made at Tenant’s request
shall be at the sole cost of Tenant. 
 12.4 Be responsible for the maintenance of the Premises (including, but not limited to, any tenant
improvements, fixtures, equipment and systems contained therein which exclusively serve the Premises), whether installed by Landlord or by Tenant, and, subject to Section 16.3, for the repair and replacement of any part of the Premises and the
Building made necessary by reason of damage thereto caused by Tenant or Tenant’s employees, servants, agents or invitees. In the event Tenant shall fail to perform such maintenance, repairs or replacements within sixty (60) days of the
date such work becomes necessary, Landlord may, but shall not be required to, perform such work and charge the amount of the expense therefor, with interest accruing and payable thereon, all in accordance with Section 20 below; 

  
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 12.5 Comply with all laws, enactments and regulations of any governmental authority relating
or applicable to Tenant’s occupancy of the Premises and any covenants, easements and restrictions governing the Land or Building, and indemnify, defend and hold Landlord harmless from all consequences from its failure to do so; provided,
however, that the foregoing shall not be interpreted to require Tenant to perform structural or capital work unless required due to Tenant’s specific use of the Premises as opposed to office use in general; 

12.6 Promptly notify Landlord of any damage to or defects in the Premises, any notices of violation received by Tenant and of any injuries to
persons or property which occur therein or claims relating thereto; 
 12.7 Subject to Section 7, pay for any alterations, improvements
or additions to the Premises and non-standard Building items installed by or for Tenant, and allow no lien to attach to the Building with respect to any of the foregoing; 

12.8 Without the prior written consent of Landlord (not to be unreasonably withheld, conditioned or delayed), not place within the Premises or
bring into the Building (i) any machinery, equipment or other personalty other than customary office furnishings and small office machinery, or (ii) other personalty having a weight in excess of the design capacity of the Building; 

12.9 Not use the Premises for the generation, manufacture, refining, transportation, treatment, storage or disposal of any Hazardous Material
or for any purpose which poses a material risk of damage to the environment; in this regard Tenant represents that it does not have a Standard Industrial Classification number as designated in the Standard Industrial Classifications Manual prepared
by the Office of Management and Budget in the Executive Office of the President of the United States that is any of 22-39 inclusive, 46-49 inclusive, 51 or 76 and will
not engage in any activity which would subject Tenant to the provisions of the Federal Comprehensive Environmental Response, Liability and Clean-Up Act (42 U.S.C. Section 9601 et seq.), the
Federal Water Pollution Control (33 U.S.C.A. Section 1151 et seq.), the Clean Water Act of 1977 (33 U.S.C.A. Section 1251 et seq.), or any other federal, state or local environmental law, regulation or ordinance; 

12.10 Comply with all commercially reasonable non-monetary rules and regulations which may hereafter
be promulgated by Landlord and with all reasonable changes and additions thereto upon notice by Landlord to Tenant (such rules and regulations, together with all changes and additions thereto, are part of this Lease); Landlord shall notify Tenant in
writing upon the promulgation of such rules and regulations or changes thereto. Landlord agrees to enforce such rules and regulations against all tenants in the Building in a non-discriminating fashion and to
take reasonable action to cause a cessation of any violation of all rules that interfere with Tenant’s use and quiet enjoyment of the Premises. In the event of any conflict between the provisions of this Lease and the provisions of any such
rules and regulations, the terms and conditions of this Lease shall control; 
 12.11 Comply with all reasonable recommendations of
Landlord’s or Tenant’s insurance carriers relating to layout, use, storage of materials and maintenance of the Premises. 
 12.12
Maintain, repair or replace, any supplemental HVAC systems and components located within and exclusively serving the Premises at its sole cost and expense. 

12.13 Paying for all separately metered utilities when due directly to the applicable utility provider. 

  
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 13. ASSIGNMENT AND SUBLETTING. 

13.1 General Provisions. Except as expressly set forth herein, Tenant shall not assign, pledge, mortgage or otherwise transfer or
encumber this Lease, nor sublet all or any part of the Premises or permit the same to be occupied or used by anyone other than Tenant or its employees without Landlord’s prior written consent (such consent not to be unreasonably withheld,
conditioned or delayed). Any consent by Landlord bereunder shall not constitute a waiver of strict future compliance by Tenant of the provisions of this Section 13 or a release of Tenant from the full performance by Tenant of any of the terms,
covenants, conditions, agreements or provisions of this Lease. For purposes of this Section 13, any transfer in Control of Tenant (or any subtenant, assignee or occupant) to a person or entity which did not previously have Control, which by
operation of law or otherwise, shall be deemed an assignment hereunder, including, without limitation, any merger, consolidation, dissolution (which in a single transaction or series of related transactions). Any assignment or subletting in
contravention of the provisions of this Section 13 shall be void. “Control” shall mean the possession, direct or indirect, of the power to direct or cause the direction of the management and polices of an entity, or ownership
of any sort, whether such ownership is achieved through the ownership of voting securities or by contract, or otherwise. Landlord shall respond to any request by Tenant for Landlord’s consent to any proposed assignment or sublease within
fifteen (15) days following delivery of such request. If Landlord fails to timely deliver to Tenant notice of Landlord’s consent, or the withholding of consent, to a proposed Transfer, Tenant may send a second (2nd) notice to Landlord,
which notice must contain the following inscription, in bold faced lettering: “SECOND NOTICE DELIVERED PURSUANT TO ARTICLE 13 OF LEASE — FAILURE TO TIMELY RESPOND WITHIN FIVE (5) BUSINESS DAYS SHALL RESULT IN DEEMED APPROVAL OF
ASSIGNMENT OR SUBLEASE.” If Landlord fails to deliver notice of Landlord’s consent to, or the withholding of Landlord’s consent, to the proposed assignment or sublease within such five (5) business day period, Landlord shall
be deemed to have approved the assignment or sublease in question. Notwithstanding anything to the contrary contained in this Section 13 or elsewhere in this Lease, any assignment or subletting shall be subject to the following further
conditions and limitations: 
 13.2 Proposed Subtenants and Assignees. Landlord will have the right to withhold its consent to a
proposed subtenant or assignee who is (a) a prospective tenant (or its designee) who is discussing with Landlord (or Landlord’s agent) regarding its need for space in the Building, or who has so negotiated within the previous four
(4) months (provided Landlord then has sufficient available space in the Building to meet the needs of such proposed subtenant or assignee); (b) a current tenant of space in the Building (provided Landlord then has sufficient available space in
the Building to meet the needs of such proposed subtenant or assignee); or (c) an Affiliate (as hereinafter defined) of a current tenant of space in the Building (provided Landlord then has sufficient available space in the Building to meet the
needs of such proposed subtenant or assignee). For purposes hereof, an “Affiliate” shall mean a corporation or other business entity that directly or indirectly controls, is controlled by, or is under common control with such
tenant. 
 13.3 Advertising. In no event shall Tenant advertise the subletting or assignment of the Premises using
signage, online or other public marketing materials (on a per rentable square foot basis) at a lower rate than Landlord is then advertising space (on a per rentable square foot basis) in the Building. Notwithstanding the foregoing, Tenant may engage
a broker to solieit subtenants or assignees to pay at a lower rate than Landlord is then advertising space in the Building, and Tenant and any such broker may prepare and submit letters of intent and other written proposals to prospective subtenants
or assignees at such lower rates. 

  
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 13.4 Right to Share Profits. 

(a) If Landlord consents to the subletting of all or any part of the Premises, Tenant shall in consideration thereof pay to Landlord, as
Additional Rent, fifty percent (50%) of any Net Profits (as hereinafter defined) in connection with the subletting. “Profits” on a subletting shall mean the difference between (i) the amounts paid as rent and additional rent by the
subtenant to Tenant in and for each month of the sublease term and (ii) Fixed Rent and Additional Rent due and payable by Tenant to Landlord in and for each month of the sublease term, in each and every month when the former exceeds the latter,
provided, however, that if a sublease involves less than the entire Premises, the amounts paid by Tenant to Landlord used in subpart (ii) above shall be prorated each month to reflect the portion of the Premises being sublet. “Net
Profits” on a subletting shall mean monthly Profits reduced by an amount equal to the quotient found by taking the total reasonable and customary attorneys’ fees, real estate brokerage commissions, commercially reasonable free rent
periods and alteration expenses (if any), paid and incurred by Tenant in connection with the subletting, and dividing by the number of months in the sublease term. 

(b) If Landlord consents to the assignment of this Lease, Tenant shall in consideration thereof pay to Landlord fifty percent (50%) of any Net
Consideration (as hereinafter defined) in connection with the assignment. “Consideration” for an assignment shall mean any sums paid to Tenant in consideration of the assignment (other than the amount of rent and additional rent
assumed by the assignee). “Net Consideration” for an assignment shall mean Consideration reduced by an amount equal to the total reasonable and customary attorneys’ fees, real estate brokerage commissions, and alteration
expenses (if any), paid and incurred by Tenant in connection with the assignment. 
 (c) Following the completion of any sublease or
assignment, Landlord shall have the right at any time and from time to time upon reasonable prior notice to Tenant to audit and inspect Tenant’s books, records and accounts related to such sublease or assignment to verify the determination of
Additional Rent payable under Section 13.3. 
 13.5 Legal and Administrative Costs. Upon Tenant’s execution and delivery of
Landlord’s Consent document (or, if there is no Consent document, within five (5) Business Days of receipt of Landlord’s invoice), Tenant shall pay Landlord’s reasonable third-party legal and administrative costs and expenses incurred
in processing each of Tenant’s subletting and assignment requests, which shall be paid whether or not Landlord consents to such subletting or assignment. 

13.6 Right to Recapture. If Tenant shall give Landlord notice of its desire to assign this Lease, or to sublet a full floor or more of
the Premises for a period of more than three (3) years (a “Non-Permitted Sublet”) for a term (and in each case, other than pursuant to a Permitted Transfer), Landlord shall be entitled, by written notice delivered to Tenant within
fifteen (15) days following Tenant’s delivery of a request for Landlord’s consent to such sublease or assignment, to cancel this Lease with respect to the applicable portion of the Premises and this Lease shall end, with respect to such
portion of the Premises, on the date specified in such notice, with the same force and effect as if such date were the date specified herein for the expiration hereof, and the rent (i.e., Fixed Rent and Additional Rent) provided for under this Lease
shall be apportioned and adjusted as of the effective date of such cancellation. 

  
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 13.7 Permitted Transfer. Notwithstanding any other provision of this Article 13 to
the contrary, Tenant shall have the right to assign or sublease the Premises without securing consent of Landlord, but upon prior notice to Landlord (unless such notice is precluded by applicable law or confidentiality agreement, in which event such
notice shall be provided as soon as permissible) (the “Permitted Transferee Notice”), to: (i) any Affiliate of Tenant; (ii) any entity which
succeeds-in-interest to Tenant by way of merger or consolidation; or (iii) any entity which is the successor in interest to Tenant due to the sale of all the stock
or substantially all of the assets of Tenant (collectively, a “Permitted Transferee” and any such transaction a “Permitted Transfer”). Notwithstanding the foregoing, the Permitted Transferee must have a net worth
equal to or greater than the Tenant’s net worth measured as of the Effective Date and Tenant shall remain primarily liable for its obligations under the Lease and shall produce documentation reasonably requested by Landlord evidencing the
Permitted Transfer. Any other assignment or sublease shall be only upon the prior written consent of Landlord which consent shall not be unreasonably withheld, delayed or conditioned and shall be further governed by Section 13.1 – 13.5.

 14. EMINENT DOMAIN. If the whole or a material portion of the Premises (or use or occupancy of the Premises) shall be taken or condemned by a
governmental or quasi-governmental authority for any public or quasi-public use or purpose (including sale under threat of such a taking), or if the owner elects to convey title to the condemnor by a deed in lieu of condemnation, or if all or any
portion of the Land or Building are so taken, condemned or conveyed and as a result thereof, in Landlord’s reasonable but sole judgment, the Premises cannot be used for Tenant’s permitted use as set forth herein, then this Lease shall
cease and terminate as of the date when title vests in such governmental or quasi-governmental authority and Fixed Rent and Additional Rent shall be abated on the date when such title vests in such governmental or quasi-governmental authority. If
less than a material portion of the Premises is taken or condemned by any governmental or quasi-governmental authority for any public or quasi-public use or purpose (including sale under threat of such a taking) such that Tenant is still able to
conduct its business operations in the Premises, as diminished, without undue interruption or difficulty, Fixed Rent and Tenant’s Proportionate Share shall be equitably adjusted (on the basis of the number of square feet before and after such
event) on the date when title vests in such governmental or quasi-governmental authority and this Lease shall otherwise continue in full force and effect. In any case, Tenant shall have no claim against Landlord for any portion of the amount that
may be awarded as damages as a result of any governmental or quasi-governmental taking or condemnation (or sale under threat or such taking or condemnation); and all rights of Tenant to damages therefor are hereby assigned by Tenant to Landlord. The
foregoing shall not, however, deprive Tenant of any separate award for moving expenses, dislocation damages or for any other award which would not reduce the award payable to Landlord. 

15. FIRE OR OTHER CASUALTY. 

15.1 In the event of damage to or destruction of the Premises caused by fire or other casualty, or any such damage to or
destruction of the Building necessary to provide normal services and access to the Premises in accordance herewith (“Event of Casualty”), Landlord will, within thirty (30) days following written notice thereof from Tenant of an
Event of Casualty, deliver to Tenant an estimate of the time necessary to repair the damage in question such that the Premises may be used by and accessible to Tenant and such notice will be based upon the review and opinions of Landlord’s
architect and contractor (“Landlord’s Repair Notice”). Landlord shall undertake to make repairs and restorations with reasonable diligence, unless this Lease has been terminated by Landlord or Tenant as hereinafter provided or
unless any mortgagee which is entitled to receive casualty insurance proceeds fails to make available to Landlord a sufficient amount of such proceeds to cover the cost of such repairs and restorations. If (i) in Landlord’s reasonable
judgment (based on Landlord’s Repair Notice), the damage is of such nature or extent that more than one hundred eighty (180) days would be required (with normal work crews 

  
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 and normal work hours) to repair and restore the Premises or the Building, as the case may be; or
(ii) in Landlord’s sole judgment, the damage is of such nature or extent that it is uneconomical to repair and restore the Premises or the Building, as the case may be; or (iii) less than one (1) year remains on the then current
Lease Term (and the damages is of such nature to the extent that normal services and access to the Premises are materially disrupted), Landlord shall so advise Tenant within thirty (30) days after the Event of Casualty (“Landlord’s
Notice of Casualty”), and either party shall have ten (10) Business Days after receipt of Landlord’s Notice of Casualty to terminate this Lease by written notice to the other. If either party elects to terminate this Lease in the
case described in clauses (i), (ii) or (iii) above, then the Lease Term shall expire ten (10) Business Days after such notice is given, and Tenant shall vacate the Premises and surrender the same to Landlord in accordance with the terms of
this Lease. Notwithstanding the foregoing, if Tenant was entitled to but elected not to exercise its right to terminate this Lease and Landlord does not substantially complete the repair and restoration of the Premises within two (2) months
after the expiration of the estimated period of time set forth in Landlord’s Repair Notice, which period shall be extended to the extent of any delays caused by Tenant, then Tenant may terminate this Lease by written notice to Landlord within
thirty (30) days after the expiration of such period, as the same may be so extended. 
 15.2 In the Event of Casualty, provided this
Lease is not terminated pursuant to the terms of Section 15.1 above and is otherwise in fall force and effect, and sufficient casualty insurance proceeds are available to cover the cost of such repair and restoration, Landlord shall proceed
diligently to repair and restore the Premises to substantially the same condition prior to the casualty occurrence. Landlord shall not be obligated to repair or restore any Alterations, the Premises Work, or Tenant’s Personal Property (as
defined in Section 16.1). 
 15.3 Landlord shall not insure; (a) any Alterations to the Premises; (b) any of the Initial
Improvements; or (c) any of Tenant’s Personal Property. 
 15.4 Except as set forth in Section 15.1 above, the validity and
effect of this Lease shall not be impaired in any way by the failure of Landlord to complete the repair and restoration of the Premises or the Building within one hundred eighty (180) days after the commencement of work, even if Landlord had in
good faith notified Tenant that the repair and restoration would be completed within such period, provided that Landlord proceeds diligently with such repair and restoration. In the case of damage to the Premises which is of a nature or extent that
Tenant’s continued occupancy is in the reasonable judgment of Landlord and Tenant substantially impaired, then Fixed Rent and Additional Rent otherwise payable by Tenant hereunder shall be equitably abated or adjusted for the duration of such
impairment. Tenant’s abatement period shall continue until Tenant has been given reasonable time, and sufficient access to the Premises, to rebuild the portion of the Premises it is required to rebuild, to install its property, furniture,
fixtures, data and telecommunications cabling and equipment and to move in to the Premises over the course of one (1) full weekend not to exceed the earlier of: (a) ninety (90) days; or (b) the date upon which Tenant has rebuilt the
Premises, installed its property, furniture, fixtures, data and telecommunications, and has moved into the Premises using good faith efforts. 
 16.
INSURANCE; WAIVER OF SUBROGATION. 
 16.1 Insurance. 

(a) Personal Property. Tenant agrees that those risks (including that of fire or other casualty, theft or other harm, damage or loss) to
Tenant’s Personal Property, including the loss of use of the same, which are actually covered by a Special Form policy of property insurance coverage shall be borne solely by Tenant. As used herein, “Personal Property” means
all tangible and intangible goods 

  
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 and accounts, inventory, merchandise, furniture, fixtures, equipment (including computer equipment and any
data stored thereon) and systems. Tenant shall purchase and maintain insurance in an amount adequate to repair or replace or otherwise cover its Personal Property (and the Personal Property of others held or leased by Tenant or otherwise in the
Premises), including any Alterations and the Initial Improvements. 
 (b) Business Interruption. Tenant shall maintain in full force
and effect at all times, and at its own expense, business interruption insurance in amounts adequate to cover all Fixed Rent and Additional Rent due under this Lease. 

(c) Commercial General Liability. Tenant shall maintain in full force and effect at all times, and at its own expense, commercial
general liability insurance (including contractual, host liquor and personal injury liability insurance) in an amount not less than $1,000,000.00 combined single limit bodily injury and property damage per occurrence and $2,000,000.00
annual aggregate limit per location (or such higher limits as may be reasonably determined by Landlord from time to time, provided that such higher limits are reasonably commensurate with the limits then being required of similar tenants by owners
of Comparable Buildings. 
 (d) Automobile Liability. For any Tenant owned vehicles, Tenant shall maintain in full force and effect at
all times, and at its own expense, automobile liability insurance in an amount not less than $1,000,000.00 combined single limit bodily injury and property damage per accident. 

(e) Workers’ Compensation and Employers’ Liability. Tenant shall maintain in full force and effect at all times, and at its
own expense, the statutory limits of workers’ compensation and employers’ liability insurance in amounts adequate to satisfy the umbrella underlying requirements. 

(f) Excess/Umbrella Liability. Tenant shall maintain in full force and effect at all times, and at its own expense, umbrella liability
coverage in an amount not less than $2,000,000.00 per occurrence. Umbrella liability coverage is to be in excess of the commercial general liability, automobile liability and employers’ liability requirements outlined in Sections 17.1
(e), (d) and (e) above. 
 (g) Liquor Liability. Intentionally Deleted. 

(h) The liability coverage in the insurance policies required in Sections 16.1 (c) and (d) above shall name Landlord as additional insureds on
a primary non-contributing basis. All insurance policies required in Sections 16.1 (a) – (g) above shall be issued by companies authorized to do business in Massachusetts with an A.M. Best’s
financial rating of A- or better and a size class rating of VII or larger or otherwise acceptable to Landlord, At or prior to Tenant’s occupancy of any space in the Building, Tenant shall deposit with
Landlord evidence of insurance (in ACORD Form) or other proof satisfactory to Landlord for each of the insurance policies Tenant is required to carry in compliance with its obligations under this Lease. Tenant agrees to give at least thirty
(30) days prior written notice to Landlord of any cancellation of any required coverage. 
 16.2 Insurance During Construction.
In addition, during the performance of any construction by Tenant on the Premises, in addition to the above coverage required to be maintained by Tenant, Tenant shall cause the general contractor performing the work to carry: (a) commercial
general liability insurance in an amount not less than $1,000,000.00 combined single limit bodily injury and property damage per occurrence and $2,000,000.00 annual aggregate limit per location (or such higher limits as may be
determined by Landlord from time to time); (b) the statutory limits of workers’ compensation and employers’ liability insurance in amounts adequate to satisfy the umbrella underlying requirements; (c) 

  
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 umbrella liability coverage in an amount not less than $2,000,000.00 per occurrence (to be in excess
of the commercial general liability and employers’ liability requirements outlined in Sections 17.2 (a) and (b) above); and (d) all risk installation floater insurance (on the complete value / full coverage form) to protect
Landlord’s interest and that of Tenant, contractors and subcontractors during the course of the construction with a limit of not less than the total replacement cost of the completed improvements under construction. Such contractor insurance
policies shall name Landlord Parties as additional insureds on a primary non-contributing basis. 

16.3 Waiver of Subrogation. Notwithstanding any other provision of this Lease to the contrary, Landlord and Tenant hereby release each
other from any and all liability or responsibility to the other or anyone claiming through or under them by way of subrogation or otherwise for any loss or damage to property caused by fire or other casualty, even if such fire or other casualty
shall have been caused by the fault or negligence of the other party, or anyone for whom such party may be responsible, provided, however, that this release shall be applicable and in full force and effect only to the extent permitted by law and
only to the extent that the cost of repairing such damage is covered by insurance or would have been covered by insurance proceeds payable under any policy (including the deductible and/or uninsured portion thereof) (x) required to be
maintained under this Lease, but not so maintained or (y) any policy actually maintained by a party hereunder. Each policy of such insurance shall, if obtainable from the insurer without additional expense, contain a waiver of subrogation by
insurer against Landlord or Tenant, as the case may be. If the inclusion of such a provision would involve an additional expense, either party, at its expense, may require such a provision to be inserted in the other’s policy. In the event a
party is unable to obtain such a waiver, it shall immediately notify the other of this inability. In the absence of such notification, each party shall be deemed to have obtained such a waiver of subrogation. 

16.4 Landlord’s Insurance. At all times during the Term, Landlord will maintain the following insurance coverage:

 (a) Replacement Cost Coverage. Landlord shall maintain in full force and effect at all times, and at its own expense, insurance for
and in an amount no less than the full replacement cost of the Building. 
 (b) Commercial General Liability. Landlord shall maintain
in full force and effect at all times, and at its own expense, commercial general liability insurance in an amount not less than $1,000.000.00 combined single limit bodily injury and property damage per occurrence and $10,000.000.00
annual aggregate limit per location. 
 (c) Additional Insurance. Landlord shall maintain in full force and effect at all times, at
its own expense, additional insurance coverage as it deems appropriate. 
 17. INSPECTION; ACCESS; CHANGES IN BUILDING FACILITIES. 

17.1 Landlord, its agents, employees and contractors may enter the Premises at any time in response to an emergency and at other reasonable
times upon reasonable advance notice to Tenant (i) to examine, inspect and protect the Premises and the Building; (ii) to make such repairs, replacements and improvements as Landlord may reasonably deem necessary to the Premises and the
Building; (iii) during the last twelve (12) months of the Lease Term, or of any extension or renewal thereof, to show it to prospective tenants; (iv) or any at any time upon reasonable notice to show the Premises to prospective
purchasers of the Building or Landlords mortgagee(s). Landlord may, at any time, affix to any suitable part of the exterior of the Building in which the Premises is located a notice for letting the Premises or the Building or selling the Building.

  
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 17.2 Landlord shall have access to and use of all areas in the Premises (including exterior
Building walls, core corridor walls and doors and any core corridor entrances), any roofs adjacent to the Premises, and any space in or adjacent to the Premises used for shafts, stacks, pipes, conduits, fan rooms, ducts, electric or other utilities,
sinks or other Building facilities, as well as access to and through the Premises for the purpose of operation, maintenance, decoration and repair, provided, however, that except in emergencies such access shall not be exercised so as to interfere
unreasonably with Tenant’s use of the Premises. Tenant shall permit Landlord to install, use and maintain pipes, ducts and conduits within the demising walls, bearing columns and ceilings of the Premises, provided that the installation work is
performed at such times and by such methods as will not materially interfere with Tenant’s use of the Premises, materially reduce the floor area thereof or materially and adversely affect Tenant’s layout, and further provided that Landlord
performs all work with due diligence and care so as to not damage Tenant’s Persona] Property or the Premises. Landlord and Tenant shall cooperate with each other in the location of Landlord’s and Tenant’s facilities requiring such
access. 
 17.3 Landlord reserves the right at any time, without incurring any liability to Tenant therefor, to make such changes in or to
the Building and the fixtures and equipment thereof, as well as in or to the street entrances, halls, foyers, passages, elevators, if any, and stairways thereof, and garages as it may deem necessary or desirable. 

17.4 Tenant shall have the right to require that Landlord be accompanied by a representative of Tenant during any such entry pursuant to this
Section 17, provided, however, that Tenant shall grant entry to Landlord in a timely manner and such entry will not hindered by or restricted by lack of availability of a Tenant escort. If any such work takes place after Normal Business Hours
and, as a consequence Tenant elects to have a representative monitor the activities of Landlord in the Premises following Normal Business Hours, Landlord will reimburse Tenant, within thirty (30) days following delivery of an invoice therefore,
for the reasonable cost incurred by Tenant associated with such representative’s monitoring of Landlord’s activities within the Premises (such cost to include, if applicable, any “overtime” or “after hours” charge
payable to such representative and/or applicable third-party fees or costs incurred by Landlord in retaining a third-party representative to perform such monitoring work). Landlord shall use diligent efforts to ensure that the performance of any
work of repairs or alterations pursuant to this Section 17 shall not interfere with Tenant’s use of the Premises (or any portion thereof) for Tenant’s business purposes (such efforts to include limiting the performance of any such
work which might be disruptive to weekends or the evening and the cleaning of any work area prior to the commencement of the next business day). To the extent that Landlord installs, maintains, uses, repairs or replaces pipes, cables, ductwork,
conduits, utility lines, and/or wires through hung ceiling space, exterior perimeter walls and column space, adjacent to and in demising partitions and columns, in or beneath the floor slab or above, below, or through the Premises, then in the
course of making any such installation or repair: (w) Landlord shall not interfere unreasonably with or interrupt the business operations of Tenant within the Premises; (x) Landlord shall not reduce Tenant’s usable space, except to a
de minimus extent, if the same are not installed behind existing walls or ceilings; (y) Landlord shall box in any of the same installed adjacent to existing walls with construction materials substantially similar to those existing in the
affected area(s) of the Premises; and (z) Landlord shall repair all damage caused by the same and restore such area(s) of the Premises to the condition existing immediately prior to such work. 

  
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 17.5 In the event that Tenant is prevented from using, and does not use, the Premises or any
portion thereof, as a result of any repair, maintenance or alteration performed by Landlord and for which Landlord is responsible under the Lease and was not caused by Tenant or which Landlord failed to perform which substantially interferes with
Tenant’s use of or ingress to or egress from the Building or Premises (an “Abatement Event”), then Tenant shall give Landlord notice of such Abatement Event, and if such Abatement Event continues for the Eligibility Period,
then the Rent payable hereunder shall be abated or reduced, as the case may be, after expiration of the Eligibility Period for such time that Tenant continues to be so prevented from using, and does not use, the Premises, or any portion thereof, in
the proportion that the rentable area of the portion of the Premises that Tenant is prevented from using, and does not use, bears to the total rentable area of the Premises. 

18. DEFAULT. Any other provisions of this Lease notwithstanding, it shall be a Tenant event of default (“Event of Default”) under this
Lease if; (a) Tenant fails to pay any installment of Fixed Rent, Additional Rent or other sum payable by Tenant hereunder when due and such failure continues for a period of five (5) days after written notice from Landlord (provided,
however, that Tenant shall be responsible for reimbursing Landlord for Landlord’s reasonable administrative and legal expenses, if any, incurred by Landlord in connection with providing more than one (1) written notice per twelve
(12) month period); or (b) Tenant fails to perform or observe any other covenant, condition or agreement of this lease and such failure continues after written notice given by or on behalf of landlord to tenant for more than thirty
(30) days (unless, due to the nature of such failure, it is not reasonably possible to cure such failure within thirty (30) days, in which event Tenant shall only be default hereunder if Tenant fails to commence such cure within such
thirty (30) day period and thereafter diligently prosecute such cure to completion); or (c) Tenant uses or occupies the Premises other than as permitted hereunder; or (d) [INTENTIONALLY OMITTED]; or (e) Tenant files a petition
commencing a voluntary case, or has filed against it a petition commencing an involuntary case, under the federal bankruptcy code (title 11 of the unites states code), as now or hereafter in effect, or under any similar law, or files or has filed
against it a petition or answer in bankruptcy or for reorganization or for an arrangement pursuant to any state bankruptcy or insolvency law or any similar state law, and, in the case of any such involuntary action, such action shall not be
dismissed, discharged or denied within sixty (60) days after the filing thereof, or tenant consents to or acquiesces in the filing thereof; or (f) a custodian, receiver, trustee or liquidator of tenant or of all or substantially all of
tenant’s personal property or of the premises shall be appointed in any proceedings brought by or against tenant and, in the latter case, such entity shall not be discharged within sixty (60) days after the appointment thereof, or tenant
consents to or acquiesces in the appointment thereof; or (g) Tenant shall admit in writing its inability to pay its debts as they become due, or shall make an assignment of tenant’s lease obligations for the benefit of or enter into an
agreement with its creditors; or (h) there is committed by Tenant any other act. or omission which is stated in this lease to be an Event of Default 

19. LANDLORD’S RIGHTS AND REMEDIES. 

19.1 Landlord’s Remedies. In addition to all other rights and remedies of Landlord, if an Event of Default shall occur, Landlord
may, at its option, at any time thereafter exercise any one or more of the following remedies: 
 (a) Termination of Lease. Landlord
may terminate this Lease, by written notice to Tenant, without any right by Tenant to reinstate its rights by payment of rent due or other performance of the terms and conditions hereof. Upon such termination Tenant shall immediately surrender
possession of the Premises to Landlord, and Landlord shall immediately become entitled to receive from Tenant an amount equal to the difference between the aggregate of all Fixed Rent and Additional Rent reserved under this Lease for the balance of
the Lease Term, and the fair rental value of the Premises for that period, determined as of the date of such termination. 

  
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 (b) Reletting. With or without terminating this Lease, as Landlord may elect,
Landlord may re-enter and repossess the Premises, or any part thereof, and lease them to any other person upon such terms as Landlord shall deem reasonable for a term within or beyond the term of this Lease;
provided, that any such reletting prior to termination shall be for the account of Tenant, and Tenant shall remain liable for (i) all Fixed Rent, Additional Rent and other sums which would be payable under this Lease by Tenant in the absence of
such expiration, termination or repossession, less (ii) the net proceeds, if any, of any reletting effected for the account of Tenant after deducting from such proceeds all of Landlord’s expenses, including employees’ expenses,
attorneys’ fees, real estate brokerage commissions and alteration expenses (if any), incurred as a result of Tenant’s breach of this Lease. Landlord shall have no obligation to relet the Premises (x) if Landlord, or any of its
affiliates, have other comparable space available for rent, (y) for a rental less than the fair market rental then prevailing for other comparable space, or (z) under terms and conditions that are unacceptable to Landlord. If the Premises
are at the time of default sublet or leased by Tenant to others, Landlord may, as Tenant’s agent, collect rents due from any subtenant or other tenant and apply such rents to the rent and other amounts due hereunder without in any way affecting
Tenant’s obligation to Landlord hereunder. Such agency, being given for security, is hereby declared to be irrevocable. 
 (c)
Acceleration of Rent. [INTENTIONALLY OMITTED] 
 (d) Removal of Contents by Landlord. With respect to any portion of the
Premises which is vacant or which is physically occupied by Tenant, Landlord may remove all persons and property therefrom, and store such property in a public warehouse or elsewhere at the cost of and for the account of Tenant without being deemed
guilty of trespass or becoming liable for any loss or damage which may be occasioned thereby. Landlord shall have a lien for the payment of all sums agreed to be paid by Tenant herein upon all Tenant’s Personal Property, which lien is to be in
addition to Landlord’s lien now or hereafter provided by law. 
 (e) Right of Distress and Lien. Landlord shall, to the extent
permitted by law, have a right of distress for rent and lien on all of Tenant’s inventory, merchandise, furniture, fixtures and equipment in the Premises as security for Rent and all other charges payable hereunder. 

(f) Deferred/Abated Rent/Unamortized Costs. Landlord may declare any then unamortized deferred or abated rent under this Lease (assuming
amortization of such abated rent over the entire Lease Term) and any unamortized costs of improvements made by Landlord to the Premises and any unamortized brokerage commissions paid or payable by Landlord in connection with this Lease immediately
due and payable. 
 19.2 Injunction. In the event of breach or threatened breach by Tenant of any provision of this Lease, Landlord
shall have the right of injunction and the right to invoke any remedy allowed at law or in equity in addition to other remedies provided for herein. 

19.3 Waiver of Redemption. Tenant hereby expressly waives any and all rights of redemption granted by or under any present or future law
in the event this Lease is terminated, or in the event of Landlord obtaining possession of the Premises, or in the event Tenant is evicted or dispossessed for any cause, by reason of violation by Tenant of any of the provisions of this Lease. 

19.4 Not Exclusive Right. No right or remedy herein conferred upon or reserved to Landlord is intended to be exclusive of any other
right or remedy herein or by law provided, but each shall be cumulative and in addition to every other right or remedy given herein or now or hereafter existing at law or in equity by or by statute. 

  
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 19.5 Expenses. In the event that Landlord commences suit for the repossession of the
Premises, for the recovery of Fixed Rent or Additional Rent or any other amount due under the provisions of this Lease, or because of the breach of any other covenant or provision herein contained on the part of Tenant to be kept or performed, and a
breach shall be established, Tenant shall pay to Landlord all expenses incurred in connection therewith, including reasonable attorneys’ fees, through all appeals and in any bankruptcy proceedings. 

20. LANDLORD’S RIGHT TO CURE TENANT’S DEFAULT. If Tenant defaults in the making of any payment or in the doing of any act herein required to
be made or done by Tenant, then Landlord may, but shall not be required to, make such payment or do such act, and charge the amount of Landlord’s expense to Tenant, with interest accruing and payable thereon at the Default Rate as of the date
of the expenditure by Landlord or as of the date of payment thereof by Tenant, whichever is higher, from the date paid or incurred by Landlord to the date of payment hereof by Tenant; provided, however, that nothing herein contained shall be
construed or implemented in such a manner as to allow Landlord to charge or receive interest in excess of the maximum legal rate then allowed by law. Such payment and interest shall constitute Additional Rent hereunder due and payable with the next
monthly installment of Fixed Rent; but the making of such payment or the taking of such action by Landlord shall not operate to cure such default by Tenant or to estop Landlord from the pursuit of any remedy to which Landlord would otherwise be
entitled. 
 21. TENANT ESTOPPEL CERTIFICATE. Upon request, and within ten (10) business days of notice from Landlord or Landlord’s
mortgagee, Tenant shall execute and deliver a written statement certifying that this Lease is in full force and effect subject only to such modifications as may be set out; and that Tenant is in possession of the Premises and is paying rent as
provided in this Lease; and that there are no uncured defaults unless they are claimed. Any such statement may be relied upon by any prospective transferee or mortgage of all or any portion of the Building, or any assignee of any such persons;
provided, however, that no such certificate shall be deemed to amend or modify the express terms of this Lease. If Tenant fails to deliver such statement in a timely manner, Tenant shall be deemed to have acknowledged that this Lease is in full
force and effect, without modification except as may be represented by Landlord, and that there are no uncured defaults in Landlord’s performance. Upon request by Tenant, Landlord will similarly, within ten (10) business days, execute and
deliver a written statement to Tenant similar to the statement described above, which may be relied upon by any proposed assignee or subtenant of Tenant, as well as any entity proposing to extend financing to Tenant. 

22. SUBORDINATION, NON-DISTURBANCE AND ATTORNMENT AGREEMENT. 

22.1 Subject to the execution of the Subordination, Non-Disturbance, and Attornment Agreement
(“SNDA”) in the form attached hereto as Exhibit “F”, this Lease and the estate, interest and rights hereby created are subordinate to any mortgage now or provided Tenant receives a new SNDA, hereafter placed upon
the Building or the Land or any estate or interest therein, including, without limitation, any mortgage on any leasehold estate, and to all renewals, modifications, consolidations, replacements and extensions of the same as well as any substitutions
therefor. Tenant agrees that in the event any person, firm, corporation or other entity acquires the right to possession of the Building or the Land, including any mortgagee or holder of any estate or interest having priority over this Lease, Tenant
shall, if requested by such person, firm, corporation or other entity and provided Tenant has received an SNDA from such entity, attorn to and become the tenant of such person, firm, corporation or other entity, upon the same terms and conditions as
are set forth herein for the balance of the Lease Term. Notwithstanding the foregoing, any mortgagee 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 and delivery, and in that event, such mortgagee shall have the same rights with respect to this Lease as though it had been executed prior to the execution
and delivery of the mortgage. 

  
 - 23 - 

 22.2 Upon request, and within ten (10) business days written notice given by or on
behalf of Landlord, any mortgagee, any ground or superior lessor of the Building or the Land, or other successor to the interests of Landlord thereto, Tenant shall execute and deliver, as appropriate, any instruments in recordable form as may be
required by such parties, including a SNDA substantially similar to the form attached hereto as Exhibit “F” in order to confirm or effect the subordination or priority of this Lease, as the case may be, and the attornment of Tenant
to future landlords in accordance with the terms of Section 23 and such parties’ requirements. Tenant’s failure to execute and deliver the SNDA within ten (10) business days notice shall: (a), if such failure continues for an
additional three (3) business days after notice from Landlord, constitute an Event of Default and (b) serve to irrevocably appoint Landlord as Tenant’s
attorney-in-fact to execute and deliver such agreement for and on behalf of Tenant. 

23. FINANCIAL STATEMENTS. [INTENTIONALLY OMITTED] 

24. HOLDING OVER. If Tenant retains possession of the Premises or any part thereof after the termination of this Lease or expiration of the Lease Term
or otherwise in the absence of any written agreement between Landlord and Tenant concerning any such continuance of the term, Tenant shall pay Landlord as liquidated damages for such holding over alone, an amount, calculated on a per diem basis for
each day of such unlawful retention commencing after the first thirty (30) days of holdover equal to three hundred percent (300%) of the Fixed Rent and Additional Rent and any other sums due under the Lease by Tenant and all other terms and
conditions of the Lease shall remain in full force and effect. Without limiting any rights and remedies of Landlord resulting by reason of the wrongful holding over by Tenant, or creating any right in Tenant to continue in possession of the
Premises, all Tenant’s obligations with respect to the use, occupancy and maintenance of the Premises shall continue during such period of unlawful retention. 

25. SURRENDER OF PREMISES. Tenant shall, at the end of the Lease Term, or any extension thereof, promptly surrender the Premises in good order and
condition, and in conformity with the applicable provisions of this Lease, excepting only reasonable wear and tear. Upon the expiration or earlier termination of this Lease, and prior to Tenant vacating the Premises, Landlord and Tenant shall
jointly inspect the Premises and Tenant shall pay to Landlord the amount reasonably estimated by Landlord as necessary to put the Premises in the condition required hereunder. Any work required to be done by Tenant prior to its vacating of the
Premises which has not been completed upon such vacating of the Premises, shall be completed by Landlord and billed to Tenant. Any Security Deposit held by Landlord shall be credited against the amount payable by Tenant under this Section. If Tenant
abandons or surrenders the Premises, or is dispossessed by process of law or otherwise, Tenant shall remove its Personal Property from the Premises. If Tenant fails to remove its Personal Property, Landlord, at its option may treat such failure as a
hold over, and/or may (without liability to Tenant for loss thereof), at Tenant’s sole cost and expense and in addition to Landlord’s other rights and remedies under this Lease, at law or in equity: (a) remove and store such items;
and/or (b) upon ten (10) days prior written notice to Tenant, sell such items at private or public sale for such price as Landlord at its discretion may obtain. Landlord shall apply the proceeds of any such sale to any amounts due to
Landlord under this Lease from Tenant (including Landlord’s attorneys fees and other costs incurred in the removal, storage and/or sale of such items), with any remainder to be paid to Tenant. 

26. REMOVAL OF TELECOM WIRES. Tenant shall be required to remove any and all telecommunications wires, cables and similar installations which were
installed by or on behalf of Tenant from the Premises upon expiration or earlier termination of this Lease unless otherwise directed by Landlord. In the event Tenant is require to remove such wiring, Tenant shall leave such wiring in good safe
working order and condition, properly bundled, labeled, capped or sealed at each end, and in each telecommunication closet and junction box. 

  
 - 24 - 

 27. BROKERS. Each party represents and warrants to the other that they have not made any agreement or
taken any action which may cause anyone to become entitled to a commission as a result of the transactions contemplated by this Lease, and each will indemnify and defend the other from any and all claims, actual or threatened, for compensation by
any such third person by reason of such party’s breach of their representation or warranty contained in this Section 27 except for Richards Barry Joyce & Partners, and Intercontinental Management, Corp, representing Landlord
exclusively and Jones Lang LaSalle, representing Tenant exclusively. Landlord will pay any commission due to brokers hereunder pursuant to its separate agreement(s). 

28. NOTICES. All notices or other communications hereunder shall be in writing and shall be deemed to have been given: (a) if delivered by hand,
by messenger or by an express delivery service (FedEx, UPS, DHL, etc.), then if and when delivered (or if delivery is refused, when refused) to the respective parties at the below addresses (or at such other address as a party may hereafter
designate for itself by notice to the other party as required hereby), provided that if such notice is delivered on a weekend or holiday, it should be deemed given on the next-succeeding business day, or (b) if mailed, then on the third
Business Day following the date on which such communication is deposited in the United States mails, by first class registered or certified mail, return receipt requested, postage prepaid, and addressed to the respective parties at the below
addresses (or at such other address as a party may hereafter designate for itself by notice to the other party as required hereby). Refusal to accept delivery shall constitute receipt. 

 

					
	28.1        	 	If to Landlord:	  	 Kendall Square Entity, Inc.
 c/o
Intercontinental Real Estate Corporation
 1270 Soldiers Field Road

Boston, MA 02135
 ATTN: Paul Charos, Asset Manager

			
		 	With a copy to:	  	 Andrea Salvi, Esq.
 Bradley &
Associates
 1270 Soldiers Field Road
 Boston, MA
02135

			
	28.2        	 	If to Tenant:	  	 1355 Market Street, Suite 900
 San Francisco, CA
94103
 Attn: Director of Facilities
  

1355 Market Street, Suite 900
 San Francisco, CA 94103

Attn: Legal Department

 29. MISCELLANEOUS. 

29.1 Authority. Tenant represents and warrants that it is duly formed and in good standing, and has full corporate or partnership power
and authority, as the case may be, to enter into this Lease and has taken all corporate or partnership action, as the case may be, necessary to carry out the transaction contemplated herein, so that when executed, this Lease constitutes a valid and
binding obligation enforceable in accordance with its terms. 

  
 - 25 - 

 29.2 Successors and Assigns. The obligations of this Lease shall be binding upon and
inure to the benefit of the parties hereto and their respective successors and assigns; provided that Landlord and each successive owner of the Building shall be liable only for obligations accruing during the period of its ownership or interest in
the Building and the assumption by the transferee of the obligations of Landlord hereunder, and from and after the transfer by Landlord or such successive owner of its ownership or other interest in the Building, Tenant shall look solely to the
successors in title for the performance of Landlord’s obligations hereunder arising thereafter. 
 29.3 Waivers. No delay or
forbearance by a party hereto in exercising any right or remedy hereunder or in undertaking or performing any act or matter which is not expressly required to be undertaken by such party shall be construed, respectively, to be a waiver of such
party’s rights or to represent any agreement by such party to undertake or perform such act or matter thereafter. 
 29.4 Waiver of
Trial by Jury. Landlord and Tenant hereby consent to the exclusive jurisdiction of the courts of the state where the Premises are located in any and all actions or proceedings arising under this Lease, and irrevocably agrees to service of
process in accordance with Section 28 above. Landlord and Tenant agree to waive trial by jury in any action, proceeding or counterclaim brought by either of the parties hereto against the other on any matter whatsoever arising out of or in any
way connected with this Lease, the relationship of Landlord and Tenant, Tenant’s use of or occupancy of the Premises and/or any claim of injury or damage and any emergency or any other statutory remedy. 

29.5 Limitation of Landlord’s Liabilities. Tenant shall look solely to Landlord’s interest in the Building and rents derived
therefrom and Landlord’s insurance proceeds for enforcement of any obligation hereunder or by law assumed or enforceable against Landlord, and no other property or other assets of Landlord shall be subjected to levy, execution or other
enforcement procedure for the satisfaction of Tenant’s remedies or with respect to this Lease, the relationship of landlord and tenant hereunder or Tenant’s use and occupancy of the Premises. 

29.6 Time of the Essence. All times, wherever specified herein for the performance by Landlord or Tenant of their respective obligations
hereunder, are of the essence of this Lease. 
 29.7 Severability. Each covenant and agreement in this Lease shall for all purposes be
construed to be a separate and independent covenant or agreement. If any provision in this Lease or the application thereof shall to any extent be invalid, illegal or otherwise unenforceable, the remainder of this Lease, and the application of such
provision other than as invalid, illegal or unenforceable, shall not be affected thereby; and such provisions of this Lease shall be valid and enforceable to the fullest extent permitted by law. 

29.8 Headings and Terms. The title and headings of this Lease are for convenience of reference only and shall not in any way be utilized
to construe or interpret the agreement of the parties as otherwise set forth herein. The term “Landlord” and term “Tenant” as used herein shall mean, where appropriate, all persons acting by or on behalf of the respective
parties, except as to any required approval, consents or amendments, modifications or supplements hereunder when such terms shall only mean the parties originally named on the first page of this Lease as Landlord and Tenant, respectively, and their
agents so authorized in writing. 

  
 - 26 - 

 29.9 Lease Not Binding Until Executed and Delivered. This Lease shall not bind
Landlord unless and until it has been signed and delivered by Tenant, received and accepted by Landlord, and then countersigned and redelivered by Landlord to Tenant. 

29.10 Counterparts. This Lease may be executed in three (3) or more counterparts, each of which shall be deemed an original, but
all of which together shall constitute one and the same lease agreement. 
 29.11 Amendment and Modification. This Lease, including
all Exhibits and Addenda attached hereto, each of which is incorporated in this Lease, contains the entire agreement between the parties hereto, and shall not be amended, modified or supplemented unless by agreement in writing signed by both
Landlord and Tenant. 
 29.12 Governing Law. This Lease shall be governed by and construed in accordance with the laws of the State of
Massachusetts. 
 30. PARKING. Tenant shall have a license to use up to forty-eight (48) assigned parking spaces at the rate of ***
dollars ($***) per space per month, which amount is subject to change on an annual basis (consistent with the rates charged to all other users of the parking facility), for the parking of registered and insured passenger vehicles (excluding trucks)
of its own or of its employees in the parking garage area of the Building. In addition, Tenant shall pay to Landlord the amount of *** dollars ($***) for each parking transmitter that Tenant requests to access the parking facilities, which amount
shall be returned to Tenant upon expiration of this Lease provided the transmitters are returned to Landlord in the condition as they were originally provided to Tenant, reasonable wear and tear excepted. All such parking rights shall be subject to
the reasonable rules and regulations of Landlord of general applicability; provided however, Landlord shall have no duty to enforce the same, and shall have the right to waive the applicability of the same on a case by case basis, in its sole
discretion. All such parking and use of the lot for access and egress shall be at the user’s sole risk, and Landlord shall not be responsible for any property damage or loss or any personal injury related thereto, except for any personal injury
proximately caused by the negligence or willful misconduct of Landlord. Tenant shall inform any of its employees or agents utilizing such parking right of the aforesaid limitation of liability, and Tenant shall indemnify Landlord, its managing agent
and their employees or agents, defend them and hold them harmless against any claim, suit, judgment, or loss (relating to the use of the parking rights herein granted) suffered by them or instituted against them which is included within the
aforesaid limitation of liability. Landlord shall be responsible for snow removal/plowing of the parking areas; provided however, in the event vehicles are present in the said areas during snow removal activities, Landlord will plow around such
vehicles and shall not be required to remove any residue of snow surrounding the vehicle as a result of such plowing activity. Upon Landlord’s request Tenant and its employees shall relocate temporarily any of its or their vehicles parked in
the parking area in order to facilitate snow removal or maintenance activity being conducted by Landlord. Such parking by Tenant or its employees shall be assigned as to location. No overnight parking is permitted by Tenant or its employees without
Landlord’s specific prior written authorization. 
 31. CONTINGENCY. Tenant hereby acknowledges and confirms that another tenant (the
“Existing Tenant”) currently leases the Premises. The Existing Tenant has expressed a willingness to vacate the Premises by October 1, 2013, however, Landlord and Existing Tenant have not yet entered into a written termination
agreement. Accordingly, this Lease is contingent upon Landlord and Existing Tenant entering into a written termination agreement acceptable to Landlord in its sole discretion, pursuant to which Existing Tenant agrees to vacate the Premises on or
before October 1, 2013 (the “Termination Agreement”). Landlord will keep Tenant apprised, from time to time, of the status of Landlord’s 

  
 -27- 

 
negotiation of the proposed Termination Agreement and will promptly respond to written requests from Tenant regarding the status thereof. In the event Landlord and Existing Tenant do not enter
into a written termination agreement on or before the Lease Commencement Date, the Lease Commencement Date shall be extended accordingly with the Lease Commencement Date being the first day upon which Landlord can deliver the Premises to Tenant in
Delivery Condition, If at any time, (x) negotiations of the Termination Agreement are halted or (y) Landlord and Existing Tenant enter into the Termination Agreement, Landlord will promptly notify Tenant of such fact. 

32. EXHIBITS AND ADDENDA. Additional terms to this Lease, if any, are set forth in the Exhibits and Addenda attached hereto, which are incorporated
herein by reference as follows: 
  

	 	A.	Premises 

  

	 	B.	Fixed Rent 

  

	 	C.	Provisions Regarding Additional Rent 

  

	 	D.	Building Rules and Regulations 

  

	 	E.	Form of Subordination, Non-Disturbance and Attornment Agreement 

  

	 	F.	Extension Option 

  

	 	G.	Building Upgrades 

  

	 	H.	Lease Commencement Date Certificate 

  

	 	I.	Satellite Dish Terms and Conditions 

 [END OF TEXT; SIGNATURES FOLLOW ON NEXT PAGE.] 

  
 - 28 - 

 IN WITNESS WHEREOF, the parties hereto have caused this Lease to be
executed on the day and year first above written. 
 LANDLORD: 
  

			
	 KENDALL SQUARE ENTITY, INC.

A Massachusetts corporation

		
	By:	 	 /s/ Peter Palandjian

	Name: Peter Palandjian
	 Title: President & Treasurer 

 TENANT: 
  

			
	 TWITTER, INC.
 a Delaware
corporation

		
	By:	 	 /s/ Mike Gupta

	 Name: Mike Gupta

	Title: CFO

  
 - 29 - 

 EXHIBIT “A” 

PREMISES 
 ATTACHED
HERETO CONSISTING OF 3 PAGES. 

  
 A-1 

 

 

 

 

 

 

 EXHIBIT “B” 

FIXED RENT 
 *NOTE: Notwithstanding
the schedule with respect to Fixed Rent set forth below, with respect to the 5th Floor Premises and 6th Floor Premises, Tenant shall begin
paying Fixed Rent on the one hundred eightieth (180th) day following the Lease Commencement Date. 

*NOTE: Notwithstanding the schedule with respect to Fixed Rent set forth below, with respect to the
7th Floor Premises, Tenant shall begin paying Fixed Rent on the Lease Commencement Date. 

*** 

  
 B-1 

 EXHIBIT “C” 

PROVISIONS REGARDING ADDITIONAL RENT 
  

	1.	DEFINITIONS. 

 1.1 “Tenant’s Proportionate Share” shall mean
35.05% which is a fraction, the numerator of which shall be 47,631 rentable square feet of the Premises and the denominator of which shall be 135,874 rentable square feet of the Building. 

1.2 Operating Expenses. 

(a) “Essential Capital Improvements” shall mean (i) any labor saving device, energy saving device or other installation,
improvement or replacement which is intended for the primary purpose of reducing Operating Expenses, whether or not voluntary or required by governmental mandate (provided that the installation of such improvement is reasonably commensurate with the
practice of owners of Comparable Buildings), or (ii) any installation or improvement intended to improve the safety of tenants in the Building generally, whether or not voluntary or required by governmental mandate, or (iii) any
installation or improvement required by reason of any Legal Requirement which did not exist on the date of the execution of this Lease. 

(b) “Operating Expenses” shall mean, subject to the exclusions set forth below, any and all of Landlord’s operating costs
and expenses of any kind or nature paid or incurred in the operation, maintenance and management of the Building, and the sidewalks, roadways and parking areas located thereon, all computed on an accrual basis and in accordance with the terms of
this Lease, including but not limited to the following: 
 (i) Electricity, gas, fuel, steam, water, sewer and any other utility charges
(including surcharges) of whatever nature (excluding the use of utilities by other tenants as such may be sub-metered or directly metered pursuant to their leases); 

(ii) Any insurance premiums and deductibles paid by Landlord; 

(iii) Building personnel costs, including but not limited to salaries, wages, fringe benefits, taxes, insurance and other direct and indirect
costs (prorated, in the case of employees performing services for one or more properties, on the basis of the estimated number of hours spent performing services for the Building); 

(iv) The cost of all service and maintenance contracts, including but not limited to security services, janitorial and cleaning services,
interior and exterior landscaping services, sidewalk and roadway maintenance, and snow removal; 
 (v) All other service, maintenance and
repair expenses (excluding those expenses paid by proceeds of insurance or by Tenant or by other third parties, and those solely attributable to tenants of the Building other than Tenant) and the cost of all materials and supplies therefor; 

(vi) Any other costs and expenses (other than capital items) incurred by Landlord in operating the Building; 

  
 C-1 

 (vii) The cost of any additional services not provided to the Building on the Lease
Commencement Date but thereafter provided by Landlord in the prudent management of the Building and commensurate with the practice of owners of Comparable Buildings; 

(viii) The annual amortization of any Essential Capital Improvement which is made by Landlord after completion of initial construction of the
Building, based on the useful life of the improvement plus interest at the prime interest rate (the “Prime Rate”) on the date of the expenditure on the unamortized portion thereof; 

(ix) Landlord’s central office administrative costs and overhead applicable to the Building; 

(x) Accounting fees for preparing the Operating Expense Statement and Tax Statement; and 

(xi) Management fees payable to the managing agent. 

(c) Operating Expenses shall not include: 

(i) Rent or other charges payable under any ground or underlying lease; 

(ii) Any expenditures on account of Landlord’s acquisition of air or similar development rights; 

(iii) Costs of repositioning, selling or syndicating Landlord’s interest in the Property; 

(iv) Costs with respect to any financing or refinancing of the Property, including debt service, amortization, points and commissions in
connection therewith; 
 (v) The cost of making leasehold improvements to any leasable space to prepare the same for occupancy by a tenant
thereof, or thereafter for the benefit of a particular tenant; 
 (vi) Services performed for or provided to any tenant to the extent such
services are exclusive to such tenant; 
 (vii) Advertising and promotional expenditures, contributions or gifts; 

(viii) Brokerage fees or commissions; 

(ix) Legal fees incurred in connection with Landlord’s preparation, negotiation and enforcement of leases with other tenants; 

(x) Salaries for any agents or employees of Landlord above those attributable to the operation, maintenance and management of the Building;

 (xi) Any costs which have been previously included in Operating Expenses or Taxes (whether under the same or a different category); 

  
 C-2 

 (xii) any capital item whatsoever, except as expressly set forth in Section 1.2(a)
above; 
 (xiii) repairs or other work occasioned by fire, windstorm or other insured casualty or hazard, to the extent that Landlord shall
receive proceeds of such insurance or would have received such proceeds had Landlord maintained the insurance coverage required under this Lease and diligently attempted to procure the maximum possible insurance coverage; 

(xiv) Taxes; 
 (xv) salaries of
officers, executives or other employees of Landlord, any affiliate of Landlord, or partners or affiliates of such partners or affiliates, other than any personnel engaged exclusively or primarily in the management, operation, maintenance, and repair
of the Building (but not leasing or marketing) who are working in the Building management office and whose salaries are not typically included in the management fee being paid and included in Operating Expenses; 

(xvi) any costs incurred to test, survey, clean up, contain, abate, remove or otherwise remedy any spill or discharge of Hazardous Materials
unless caused by Tenant or its agents; 
 (xvii) costs of special services (which shall not cover normal variations in repairs or the need
for repairs) not rendered to tenants generally; 
 (xviii) the cost of any service sold to any tenant or occupant of the Building for which
Landlord is entitled to be reimbursed as an additional charge or rental over and above the basic rent and escalations payable under the lease or occupancy agreement with that tenant or other occupant (including, by way of example but not limitation,
after-hours HVAC costs or over-standard electrical consumption costs incurred by other tenants or occupants); 
 (xix) reserves of any kind;

 (xx) costs incurred by Landlord in connection with rooftop communications equipment of Landlord or other persons, tenants or occupants on
the Building; 
 (xxi) any amounts paid to any person, firm or corporation related or otherwise affiliated with Landlord or any general
partner, officer or director of Landlord or any of its general partners, to the extent same materially exceeds arms-length competitive prices paid in the Cambridge, Massachusetts metropolitan area for the services or goods provided; 

(xxii) costs relating to maintaining Landlord’s existence, either as a corporation, partnership, or other entity, such as trustee’s
fees, annual fees, partnership or organization or administration expenses, deed recordation expenses, as well as the operation of the entity which constitutes Landlord, as the same are distinguished from the costs of operation of the Building, as
well as partnership accounting and legal matters, costs of defending any lawsuits with any mortgagee, costs of any disputes between Landlord and its employees, disputes of Landlord with Building management or personnel, or outside fees paid in
connection with disputes with other tenants; 
 (xxiii) costs incurred due to Landlord’s violation of any terms and conditions of this
Lease or any other lease relating to the Building or of any law, ordinance or governmental rule or regulation affecting the Building; 

  
 C-3 

 (xxiv) costs arising from the negligence of Landlord or its agents, or of any other tenant,
or any vendors, contractors, or providers of materials or services selected, hired or engaged by Landlord or its agents; 
 (xxv) costs
incurred in removing and storing the property of former tenants or occupants of the Building; 
 (xxvi) costs for acquisition of sculpture,
paintings, other objects of art, as well as the cost of insuring, repairing or maintaining the same; 
 (xxvii) the entertainment expenses
and travel expenses of Landlord, its employees, agents, partners and affiliates; and 
 (xxviii) consulting costs and expenses paid by
Landlord unless they relate exclusively to the improved management or operation of the Building. 
 (d) “Operating Year”
shall mean each calendar year or such other period of twelve (12) months through the Lease Term as hereafter may be adopted by Landlord as its fiscal year, occurring during the Lease Term. 

(e) “Operating Statement” shall mean a statement in writing signed by Landlord setting forth the actual Operating Expenses
payable by Tenant for a specified Operating Year pursuant to this Section 1.2. 
 1.3 Taxes. 

(a) “Taxes” shall mean all taxes, assessments and governmental charges, whether federal, state, county or municipal, and
whether general or special, ordinary or extraordinary, foreseen or unforeseen, imposed upon the Building, the Land, and the sidewalks, roadways and parking areas located thereon, or due to the operation thereof, whether or not directly paid by
Landlord. Taxes shall not include income taxes, excess profit taxes, franchise taxes or other taxes imposed or measured on or by the income of Landlord from the operation of the Building or the Land; provided, however, that if, due to
a future change in the method of taxation or assessment, any income, excess profit, franchise or other tax, however designated, shall be imposed in substitution, in whole or in part, for (or in lieu of) any tax, assessment or charge which would
otherwise be included within the definition of Taxes, such other tax shall be deemed to be included within Taxes as defined herein to the extent of such substitution. If Landlord incurs any expenses (including, but not limited to, reasonable
attorneys’ fees) in connection with its efforts to reduce or minimize increases in the Taxes and/or the assessed value of the Building, any and all such expenses shall be added to, and made a part of, the Taxes for the Operating Year to which
they relate. Tenant shall pay to the appropriate governmental authority any use and occupancy tax. In the event that Landlord is required by law to collect such tax, Tenant shall pay such use and occupancy tax to Landlord as Additional Rent upon
demand and Landlord shall remit any amounts so paid to Landlord to the appropriate governmental authority. Taxes shall not include (i) any excess profits taxes, franchise taxes, gift taxes, capital stock taxes, inheritance and succession taxes,
estate taxes, federal and state income taxes, and other taxes to the extent applicable to Landlord’s general or net income (as opposed to rents or receipts), (ii) penalties incurred as a result of Landlord’s negligence, inability or
unwillingness to make payments of, and/or to file any tax or informational returns with respect to, any Taxes, when due, or (iii) any real estate taxes directly payable by Tenant or any other tenant in the Building under the applicable provisions in
their respective leases, 

  
 C-4 

 (b) “Tax Year” shall mean each fiscal year or such other period of twelve
(12) months throughout the Lease Term as hereafter may be adopted by Landlord as its fiscal year, occurring during the Lease Term. 

(c) “Tax Statement” shall mean a statement in writing signed by Landlord setting forth the actual Taxes payable by Tenant for
a specified Tax Year. 
 1.4 “Operating Expense Stop” shall mean an amount equal to the actual Operating Expenses (on a per
rentable square foot basis) for the calendar year 2014 (the “Base Year”). 
 1.5 “Tax Expense Stop” shall
mean an amount equal to the actual Taxes (on a per rentable square foot basis) for the fiscal year 2015 (the “Base Tax Year”). 
  

	2.	ADDITIONAL RENT FOR OPERATING EXPENSES AND TAXES. 

 2.1 In addition to Fixed Rent, Tenant
shall pay to Landlord for each month of each Operating Year and each Tax Year, without demand (except as set forth herein), deduction or setoff, as Additional Rent: (a) beginning on January 1, 2015, Tenant’s Proportionate Share of
Operating Expenses to the extent the Operating Expenses (on a per rentable square foot basis) exceed the Operating Expense Stop; and (b) beginning on July 1, 2015, Tenant’s Proportionate Share of Taxes to the extent the Taxes (on a
per rentable square foot basis) exceed the Tax Expense Stop, in accordance with the procedures set forth below. 
 2.2 As soon as available
in each Operating Year and Tax Year during the Lease Term, Landlord shall provide Tenant with a written statement setting forth a projection of Tenant’s Proportionate Share of Operating Expenses and Taxes for such year. Commencing on the first
day of the first month following receipt of such statement and continuing until receipt by Tenant of Landlord’s statement of the next projection, Tenant shall pay to Landlord with each monthly installment of Fixed Rent an amount equal to: (a) one-twelfth (1/12th) of such projected Tenant’s Proportionate Share of Operating Expenses over the Operating Expense Stop and (b) one-twelfth (1/12th) of
such projected Tenant’s Proportionate Share of Taxes over the Tax Expense Stop. 
 2.3 Landlord shall, as soon as possible after the
close of each such Operating Year, provide Tenant with a statement of the actual Operating Expenses and Taxes for such period. Any underpayment by Tenant during such Operating Year due to the fact that projected Operating Expenses and Taxes were
less than actual Operating Expenses and Taxes shall be paid to Landlord within thirty (30) days after Tenant’s receipt of a statement for such deficiency. Any overpayment by Tenant during such Operating Year due to the fact that projected
Operating Expenses and Taxes were greater than actual Operating Expenses and Taxes shall be, at Landlord’s option, (a) applied to any other amounts of Rent then due from Tenant to Landlord, (b) credited to the next payment of Rent
coming due from Tenant to Landlord, or (c) refunded to Tenant if no Rent is then due or coming due. 
 3. ADJUSTMENT FOR VACANCIES. In
determining Operating Expenses and Tax for any Operating Year or Tax Year, if the Building was less than fully occupied during such entire year, or was less than fully operational during such entire year, then these components of Operating Expenses
which vary with variations in occupancy shall be adjusted by Landlord to reflect the amount that such expenses would normally be expected to have been, in the reasonable opinion of Landlord, had the Building been ninety-five percent (95%) occupied
and fully operational throughout such year, except that in no event shall such adjustment result in an amount less than the actual Operating Expenses. 

  
 C-5 

 4. PRO-RATIONS. If this Lease shall commence or terminate at
any time other than the first day of an Operating Year, Tenant shall be liable only for that portion of the Operating Expenses and Taxes with respect to such Operating Year as represented by a fraction, the numerator of which is the number of days
of the Lease Term which fail within the Operating Year and the denominator of which is three hundred sixty-five (365). 
 5. AUDIT. Landlord shall
maintain at all times during the Lease Term, at Landlord’s corporate office as set forth in Landlord’s notice address under the Lease, complete and accurate books of account and records prepared in accordance with generally accepted
accounting principles with respect to Operating Expenses and Taxes, and shall retain such books and records, as well as contracts, bills, vouchers, and checks, and such other documents as are reasonably necessary to properly audit Operating Expenses
and Taxes. Tenant shall have the right to examine, audit and photocopy Landlord’s books and records relating to Tenant’s Proportionate Share of Operating Expenses and Taxes for any Operating Year for a period of four (4) months
following the date that Tenant receives the Operating Statement and Tax Statement; provided, however, that (a) Tenant may exercise such right only once per twelve (12) month period; and (b) Tenant signs a confidentiality agreement in
form satisfactory to Landlord in its reasonable discretion. Tenant shall give Landlord not less than thirty (30) days’ prior written notice of its intention to examine and audit such books and records, and such examination and audit shall
take place in the city where the Premises are located. All costs of the examination and audit shall be performed by a certified public accountant and shall be on a non-eontingent fee basis and shall be borne
by Tenant; provided, however, that if such examination and audit establishes that Tenant’s Proportionate Share of Operating Expenses and Taxes for the year in question are less than the amount set forth on the Operating Statement and Tax
Statement by at least five percent (5%), then Landlord shall pay the reasonable costs of such examination and audit. If the payments made by Tenant for such year are more than Tenant’s required payment on account thereof for such Operating
Year, Landlord shall promptly refund such overpayment. If the payments made by Tenant for such year are less than Tenant’s required payment on account thereof for such Operating Year, Tenant shall pay the deficiency to Landlord within thirty
(30) days after conclusion of the examination and audit as well as Landlord’s actual out-of-pocket costs in connection with such examination and audit. The
obligation to make such refund or payment for any period within the Lease Term shall survive expiration of the Lease Term. If Tenant does not elect to exercise its right to examine and audit Landlord’s books and records for any Operating Year
within the time period provided for by this Section 5, Tenant shall have no further right to challenge Landlord’s Operating Statement and Tax Statement. 

6. SURVIVAL. If, upon the expiration or earlier termination of this Lease, the amount of any Additional Rent due hereunder has not yet been determined,
an appropriate payment from Tenant to Landlord or refund from Landlord to Tenant, shall be made promptly after such determination. 

  
 C-6 

 EXHIBIT “D” 

BUILDING RULES AND REGULATIONS 

1. The sidewalks, entrances, driveways, passages, courts, elevators, vestibules, stairways, corridors or halls shall not be obstructed or
encumbered by any tenant or used for any purpose other than for ingress to and egress from the Premises and for delivery by Landlord. There shall not be use in the space or in the public hall of the building, by either a Tenant or by jobbers or
others in the delivery or receipt of merchandise, any hand trucks, except those equipped with rubber tires and side-guards. If the Premises are situated on the ground floor of the Building, Tenant thereof shall further, at Tenant’s expense,
keep the sidewalks and curb in the front of said Premises clean and free from ice, snow, dirt and rubbish. 
 2. The water and wash closets
and plumbing fixtures shall not be used for any purposes other than those for which they were designated or constructed and no sweeping, rubbish, rags, acids or other substances shall be deposited therein, and the expense of any breakage, stoppage
or damage resulting from the violation of this rule shall be borne by the Tenant who, or whose clerks, agents, employees or visitors shall have caused it. 

3. No Tenant shall sweep or throw or permit to be swept or thrown from the Premises any dirt or other substances into any of the corridors or
halls, elevators, or out the doors or windows or stairways of the Building and Tenant shall not use, keep or permit to be used or kept any foul or noxious gas or substance in the Premises of permit or suffer the Premises to be occupied or used in a
manner offensive or objectionable to Landlord or other occupants of the Building by reason of noise, odors and/or vibrations, or interfere in any way with other tenants or those having business therein, nor shall any animals or birds be kept in or
about the Building. Smoking or carrying lighted cigars or cigarettes in the elevators or the Building is prohibited. 
 4. No awnings or
other projections shall be attached to the outside walls of the Buildings without the prior written consent of Landlord. 
 5. No sign,
advertisement, notice or other lettering shall be exhibited, inscribed, painted or affixed by any Tenant on any part of the outside of the Premises or the Building or on the inside of the Premises if the same is visible from the outside of the
Premises without prior written consent of the Landlord, except that the name of Tenant may appear on the entrance door of the Premises. In the event of the violation of the foregoing by any Tenant, Landlord may remove same without any liability, and
may charge the expense incurred by such removal to Tenant or tenants violating the rule. Interior signs on doors and directory tablet shall be inscribed, painted or affixed for each Tenant by Landlord at the expense of such Tenant, and shall be of a
size, color and style acceptable to Landlord. 
 6. Except with the prior written consent of Landlord and as Landlord may direct, no Tenant
shall mark, paint, drill into, or in any way deface any part of the Premises or the Building of which they form a part, or cut or string wires, or lay linoleum, or other similar floor covering, so that the same shall come in direct contact with the
floor of the Premises, and, if linoleum or other similar floor covering is desired to be used, and interlining of builder’s deadening felt shall be first affixed to the floor, by a paste or other similar adhesive material being expressly
prohibited. The foregoing will not prohibit Tenant from performing such work as may be necessary in the context of the normal hanging of pictures and artwork in the Premises provided the walls of the Premises are left in good condition and repair
upon expiration or earlier termination of the Lease, reasonable wear and tear excepted. 

  
 D-1 

 7. Except with the prior written consent of Landlord, no additional locks or bolts of any
kind shall be placed upon any of the doors or windows by any Tenant, nor shall any changes be made in existing locks or mechanism thereof. If requested, Tenant shall provide Landlord with a copy of a key for all new locks or bolts. Each Tenant shall
upon termination of his tenancy, restore to Landlord all keys either furnished to, or otherwise procured by such Tenant. In the event of the loss of any keys furnished to Tenant, Tenant shall pay to Landlord the cost thereof. 

8. Freight, furniture, business equipment, merchandise and bulky matter of any description shall be delivered to and removed from the Premises
only on the freight elevators and through the service entrances and corridors or in an alternative way approved by Landlord and only during hours and in a manner approved by Landlord. 

9. Canvassing, soliciting and peddling in the Building is prohibited and each tenant shall cooperate to prevent the same. 

10. Landlord shall have the right to prohibit any advertising by any tenant which, in Landlord’s opinion, tends to impair the reputation
of the Building or its desirability as a building for office, and upon written notice from the Landlord, Tenant shall refrain from or discontinue such advertising. 

11. Except for those items necessary for the cleaning and maintenance of Tenant’s business, including office supplies, which shall be
properly stored to minimize the risk of fire and explosion, Tenant shall not bring or permit to be brought or kept in or on the Premises any flammable, combustible or explosive fluid, material, chemical or substance, or cause or permit any odors of
cooking or other process, or any unusual or other objectionable odors to permeate in or emanate from the Premises. 

  
 D-2 

 EXHIBIT “E” 

FORM OF NON-DISTURBANCE, ATTORNMENT AND SUBORDINATION AGREEMENT 

ATTACHED HERETO CONSISTING OF ELEVEN (11) PAGES 

  
 E-1 

 NON-DISTURBANCE, ATTORNMENT AND SUBORDINATION
AGREEMENT 
 THIS NON-DISTURBANCE, ATTORNMENT AND SUBORDINATION AGREEMENT (this
“Agreement”) is made and entered into as of this                      day of
                    , 2013, by and among SOVEREIGN BANK, N.A., a national banking association (f/k/a Sovereign Bank) with an
address of 75 State Street, Boston, Massachusetts 02109 (hereinafter called the “Lender”), TWITTER, INC., a Delaware corporation (hereinafter called the “Tenant”, and KENDALL SQUARE ENTITY, INC., a
Massachusetts corporation, having its principal place of business at 1270 Soldiers Field Road, Boston, Massachusetts (hereinafter called the “Landlord”). 

W I T N E S S E T H: 

WHEREAS, Landlord is the owner of certain real property located in the City of Cambridge, Middlesex County, Massachusetts, and more
particularly described in Exhibit A attached hereto and made a part hereof (said property being hereinafter called the “Property”); and 

WHEREAS, Landlord and Tenant made and entered into that certain Lease, dated the          day
of                     , 2013, with respect to certain premises constituting a portion of the Property therein described, commonly known and
numbered as 141 Portland Street, Cambridge, Massachusetts (said Lease being hereinafter called the “Lease” and said premises being hereinafter called the “Leased Premises”); and 

WHEREAS, Landlord has entered into and delivered that certain Mortgage and Security Agreement dated September 11, 2009 in favor of Lender
(the “Mortgage”), conveying the Property to secure the payment of the indebtedness described in the Mortgage; and 
 WHEREAS,
Landlord has entered into and delivered that certain Collateral Assignment of Leases and Rents dated September 11, 2009 in favor of Lender (the “Assignment of Leases”), assigning all of Landlord’s right, title and interest as
lessor under the Lease to further secure the Obligations, as described and defined in the Mortgage; and 
 WHEREAS, the parties hereto
desire to enter into this Non-Disturbance, Attornment and Subordination Agreement; 
 NOW,
THEREFORE, for and in consideration of the mutual covenants hereinafter set forth and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, Lender, Tenant, and Landlord each hereby covenants and agrees
as follows: 
  

	1.	 Non-Disturbance. So long as no Event of Default (as defined in the
Lease) exists, nor any event has occurred which has continued to exist for such period of time (after notice, if any, required by the Lease) as would entitle the lessor under the Lease to terminate the Lease or would cause, without any further
action on the part of such lessor, the termination of the Lease or would entitle such lessor to dispossess Tenant, the Lease shall not be terminated, nor shall Tenant’s use, possession or enjoyment of the Leased Premises or rights under the
Lease be interfered with in any foreclosure or other action or proceeding in the nature of foreclosure instituted under or in connection with the Mortgage or in the event that Lender takes possession of the Property pursuant to any provisions of the
Mortgage or the Assignment of Leases, unless the lessor under the Lease would have had such right if the Mortgage or the Assignment of Leases had not been made, except that neither the person or entity acquiring the interest of the lessor under the
Lease as a result of any such action or proceeding or deed in lieu of any such action or proceeding (hereinafter called the “Purchaser”) nor Lender if Lender takes possession of the Property shall be

	 	
(a) liable for any act or omission of any prior lessor under the Lease; or (b) liable for the return of any security deposit which Tenant has paid to any prior lessor under the Lease; or
(c) subject to any offsets or defenses which Tenant might have against any prior lessor under the Lease; or (d) bound by any base rent, percentage rent or any other payments which Tenant might have paid for more than the current month to
any prior lessor under the Lease; or (e) bound by any amendment or modification of the Lease made without Lender’s prior written consent (other than an amendment or modification memorializing the exercise by Tenant of a right or option set
forth in the Lease); (f) personally liable for any default under the Lease or any covenant or obligation on its part to be performed thereunder as lessor; or (g) liable for any of Landlord’s Construction-Related Obligation under the Lease.
As used herein, a “Construction-Related Obligation” means any obligation of Landlord under the Lease to make, pay for, or reimburse Tenant for any alterations, demolition, or other improvements or work at the Property, including the
Premises. 

  

	2.	Attornment. Unless the Lease is terminated in accordance with Paragraph 1, if the interests of the lessor under the Lease shall be transferred by reason of the exercise of the power of sale contained in the
Mortgage (if applicable), or by any foreclosure or other proceeding for enforcement of the Mortgage, or by deed in lieu of foreclosure or such other proceeding, or if Lender takes possession of the Property pursuant to any provisions of the Mortgage
or the Assignment of Leases, Tenant shall be bound to the Purchaser or Lender, as the case may be, under all of the terms, covenants and conditions of the Lease for the balance of the term thereof and any extensions or renewals thereof which may be
effected in accordance with any option herefore in the Lease, with the same force and effect, as if the Purchaser or Lender were the lessor under the Lease, and Tenant, as lessee under the Lease, does hereby agree to attorn to the Purchaser and
Lender if it takes possession of the Property, as its lessor under the Lease. Such attornment shall be effective and self-operative without the execution of any further instruments upon the succession by Purchaser to the interest of the lessor under
the Lease or the taking of possession of the Property by Lender. Nevertheless, Tenant shall, from time to time, execute (or make good faith comments to) and deliver such instruments evidencing such attornment as Purchaser or Lender may reasonably
require. The respective rights and obligations of Purchaser, Lender and of Tenant upon such attornment, to the extent of the then remaining balance of the term of the Lease and any such extensions and renewals, shall be and are the same as now set
forth in the Lease except as otherwise expressly provided in Paragraph 1. 

  

	3.	Subordination. Tenant hereby subordinates all of its right, title and interest as lessee under the Lease to the right, title and interest of Lender under the Mortgage, and Tenant further agrees that the Lease now
is and shall at all times continue to be subject and subordinate in each and every respect to the Mortgage and to any and all increases, renewals, modifications, extensions, substitutions, replacements and/or consolidations of the Mortgage.

  

	4.	 Assignment of Leases. Tenant hereby acknowledges that all of Landlord’s right, title and interest as
lessor under the Lease is being duly assigned to Lender pursuant to the terms of the Mortgage and the Assignment of Leases, and that pursuant to the terms thereof all rental payments under the Lease shall continue to be paid to Landlord in
accordance with the terms of the Lease unless and until Tenant is otherwise notified in miring by Lender. Upon receipt of any such written notice from Lender, Tenant covenants and agrees to make payment of all rental payments then due or to become
due under the Lease directly to Lender or to Lender’s agent designated in such notice and to continue to do so until otherwise notified in writing by Lender. Landlord hereby irrevocably directs and authorizes Tenant to make rental payments
directly to Lender following receipt of such notice, and Landlord covenants and agrees that Tenant shall have the right to rely on such notice without any obligation to inquire as to whether any default exists under the Mortgage or the Assignment of
Leases or the indebtedness secured thereby, and notwithstanding 

  
 - 2 - 

	 	
any notice or claim of Landlord to the contrary, and that Landlord shall have no right or claim against Tenant for or by reason of any rental payments made by Tenant to Lender following receipt
of such notice. Tenant further acknowledges and agrees: (a) that under the provisions of the Mortgage and/or the Assignment of Leases, the Lease cannot be terminated (nor can Landlord accept any surrender of the Lease) or modified in any of its
terms, or consent be given to the waiver or release of Tenant from the performance or observance of any obligation under the Lease, without the prior written consent of Lender, and without such consent no rent may be collected or accepted by
Landlord more than one month in advance; and (b) that the interest of Landlord as lessor under the Lease has been assigned to Lender for the purposes specified in the Mortgage and the Assignment of Leases, and Lender assumes no duty, liability
or obligation under the Lease, except only under the circumstances, terms and conditions specifically set forth in the Mortgage and/or the Assignment of Leases. 

  

	5.	Notice of Default by Lessor. Tenant, as lessee under the Lease, hereby covenants and agrees to give Lender written notice properly specifying wherein the lessor under the Lease has failed to perform any of the
covenants or obligations of the lessor under the Lease, simultaneously with the giving of any notice of such default to the lessor under the provisions of the Lease. Tenant agrees that Lender shall have the right, but not the obligation, within
thirty (30) days after receipt by Lender of such notice (or within such additional time as is reasonably required to correct any such default, provided that Lender has given notice to Tenant within such initial thirty (30) day period of
Lender’s intent to attempt to correct such default and thereafter diligently prosecute such correction) to correct or remedy, or cause to be corrected or remedied, each such default before Tenant may take any action under the Lease by reason of
such default thereof. Such notices to Lender shall be delivered in duplicate to: 

 Sovereign Bank, N.A. 

75 State Street 

Boston, Massachusetts 02109 

Attn: Real Estate Division 
 or
to such other address as the Lender shall have designated to Tenant by giving written notice to Tenant at: 
 1355 Market
Street, Suite 900 
 San Francisco, CA 94103 

Attn: Director of Facilities 

with a copy to: 

1355 Market Street, Suite 900 

San Francisco, CA 94103 

Attn: Legal Department 
 , or to
such other address as may be designated by written notice from Tenant to Lender. 
  

	6.	No Further Subordination. Except as expressly provided to the contrary in Paragraph 3 hereof, Landlord and Tenant covenant and agree with Lender that there shall be no further subordination of the interest of
lessee under the Lease to any lender or to any other party without first obtaining the prior written consent of Lender. Any attempt to effect a further subordination of lessee’s interest under the Lease without first obtaining the prior written
consent of Lender shall be null and void. 

  
 - 3 - 

	7.	Limitation of Liability. Notwithstanding anything to the contrary in this Agreement or the Lease, upon any attornment pursuant to this Agreement the Lease shall be deemed to have been automatically amended to
provide that Lender or Purchaser’s obligations and liability under the Lease shall never extend beyond Lender or Purchaser’s (or their respective successors’ or assigns’) interest, if any, in the Property. 

 

	8.	Title of Paragraphs. The titles of the paragraphs of this agreement are for convenience and reference only, and the words contained therein shall in no way be held to explain, modify, amplify or aid in the
interpretation, construction or meaning of the provisions of this agreement. 

  

	9.	Governing Law. This agreement shall be governed by and construed in accordance with the laws of The Commonwealth of Massachusetts. 

 

	10.	Provisions Binding. The terms and provisions hereof shall be binding upon and shall inure to the benefit of the heirs, executors, administrators, successors and permitted assigns, respectively, of Lender, Tenant
and Landlord. The reference contained to successors and assigns of Tenant is not intended to constitute and does not constitute a consent by Landlord or Lender to an assignment by Tenant, but has reference only to those instances in which the lessor
under the Lease and Lender shall have given written consent to a particular assignment by Tenant thereunder. 

 [Remainder of
page left intentionally blank] 

  
 - 4 - 

 IN WITNESS WHEREOF, the parties have hereunto set their respective hands and seals as of the day,
month and year first above written. 
  

			
	LENDER:
	
	SOVEREIGN BANK, N.A.
		
	By:	 	 
	Name:	 	
	Title:	 	
	
	TENANT:
	
	TWITTER, INC.
		
	By:	 	 
	Name:	 	
	Title:	 	
	
	LANDLORD:
	
	KENDALL SQUARE ENTITY, INC.
		
	By:	 	 
	Name:	 	Peter Palandjian
	Title:	 	President & Treasurer

  
 - 5 - 

					
	COMMONWEALTH OF MASSACHUSETTS	  	)	  	
		  	)	  	ss.
	COUNTY OF                                    
                                         
       	  	)	  	

 On this              day of
                    , 20    , before me, the undersigned notary public, personally appeared
                            , proved to me through satisfactory evidence of identification, which was
                                         
                   , to be the person whose name is signed on the preceding or attached document, and acknowledged to me that he signed it voluntarily
for its stated purpose, as
                                         
                    of Sovereign Bank, N.A. 
  

	
	
	   

	Notary Public
	
	My commission expires:

  
 - 6 - 

  

					
	COMMONWEALTH OF MASSACHUSETTS	  	)	  	
		  	)	  	ss.
	COUNTY OF SUFFOLK                                  
                               	  	)	  	

 On this              day of
                    , 20    , before me, the undersigned notary public, personally appeared Peter Palandjian,
President and Treasurer of Kendall Square Entity, Inc., proved to me through satisfactory evidence of identification, which was Massachusetts Driver’s License, to be the person whose name is signed on the preceding or attached document, and
acknowledged to me that he signed it voluntarily for its stated purpose. 
  

	
	
	   

	Notary Public
	
	My commission expires:

 [AFFIX NOTARIAL SEAL/STAMP] 

  
 - 7 - 

					
	STATE OF CALIFORNIA	  	)	  	
	COUNTY OF                                    
                                         
       	  	)	  	

 On
                    , 20     before me,
                                         
           , Notary Public, personally appeared
                                         
                       , who proved to me on the basis of satisfactory evidence to be the person(s) whose name(s) is/are subscribed
to the within instrument and acknowledged to me that he/she/they executed the same in his/her/their authorized capacity(ies), and that by his/her/their signature(s) on the instrument the person(s), or the entity upon behalf of which the person(s)
acted, executed the instrument. 
 I certify under PENALTY OF PERJURY under the laws of the State of California that the foregoing paragraph is true and
correct. 
 WITNESS my hand and official seal. 

Signature:                        
                                         
                            (seal) 

  
 - 8 - 

 EXHIBIT A 

LEGAL DESCRIPTION TO 
 NON-DISTURBANCE, ATTORNMENT AND SUBORDINATION AGREEMENT 
 The following parcels of land with the buildings thereon
situated in Cambridge, Middlesex County, Massachusetts, bounded and described as follows: 
 PARCEL ONE (Unregistered land) 

A certain parcel of land situated on the soutbeasterly side of Davis Street in said Cambridge and bounded and described as follows: 

Being numbered 8-10 on said Davis Street and shown as Lots 5 and 6 on a plan entitled Plan of Premises in
Cambridgeport belonging to Edward Hixon dated October 25, 1882, W.A. Mason & Son, Surveyors,” recorded with Middlesex South District Registry of Deeds in Plan Book 39 as Plan No. 8 and bounded and described as follows: 

 

			
		
	NORTHWESTERLY        	  	by said Davis Street forty two and 42/100 (42.42) feet;
		
	NORTHEASTERLY	  	 by land of owners unknown, fifty three and 97/100 (53.97) feet;

		
	SOUTHEASTERLY	  	by lot 7 on said plan forty one and 49/100 (41.49) feet; and
		
	SOUTHEASTERLY	  	by the center line of a passageway shown on said plan fifty three and 95/100 (53.95) feet.

 Containing 2,264 square feet. 

Together with and subject to passageway rights as appear of record. 

For title reference, see below.  
 PARCEL TWO
(Unregistered land) 
 Being numbered 6 on said Davis Street and shown as lots 7, 8 and 9 on the plan hereinbefore referred to and bounded and described as
follows: 
 Beginning at a point in the center of the passageway shown on said plan 63.95 feet southerly from Davis Street, thence running 

  
 - 9 - 

 
			
		
	SOUTHEASTERLY        	  	40.08 feet, thence turning and running;
		
	NORTHEASTERLY	  	18.75 feet, thence turning and running;
		
	SOUTHEASTERLY	  	17.60 feet, thence turning and running;
		
	NORTHEASTERLY	  	again 18.16 feet, thence turning and running;
		
	NORTHWESTERLY	  	39.52 feet, thence turning and running;
		
	SOUTHWESTERLY	  	by lots 5 and 6 on said plan 41.49 feet to the point of beginning.

 For title reference, see below. 

PARCEL THREE (Registered land) 
  

			
		
	NORTHEASTERLY        	  	by Broadway, one hundred forty-one and 15/100 feet;
		
		  	 SOUTHEASTERLY by Portland Street, one hundred ninety-eight and 90/100 feet;

		
	SOUTHWESTERLY	  	 by land now or formerly of Howard M. Faust, forty-eight and 77/100 feet;

		
	NORTHWESTERLY	  	 by land now or formerly of George B. Gilbert et al, six and 74/100 feet;

		
	SOUTHWESTERLY	  	 by land now or formerly of said Gilbert et al and land formerly of Predore Stacey, one hundred twelve and 96/100 feet; and

		
	NORTHWESTERLY	  	 by Davis Street, one hundred eighty-five and 73/100 feet,

 All of said boundaries of Parcel Three are determined by the Land Court to be located as shown on a Plan, as approved by
the Court, filed in the Land Registration Office, a copy of said portion of which is filed in the Registry of Deeds for the South Registry District of Middlesex County in Registration Book 28, Page 285, with Certification 4477. (Plan No. 4190A).

 Title Reference for Parcels One and Two: Deed of UST Corp., dated December 17, 1985, and recorded with the Middlesex South District Registry
of Deeds at Book 16682, Page 565. 
 Title Reference for Parcel Three: Certificate of Title No. 175562, issued by the South Registry District of
Middlesex County. 

  
 - 10 - 

 EXHIBIT “F” 

EXTENSION OPTION 
 1. Subject to:
(a) Tenant not being in an Event of Default upon exercise of the Extension Option; and (b) Tenant not having assigned its interest in the Lease or entered into a Non-Permitted Sublet which is in
effect as of the date of Tenant’s exercise of the option set forth, herein (except, in each case, in connection with a Permitted Transfer), Tenant shall have the option to extend this lease (the “Extension Option”) for one
(1) additional period of five (5) years (such term being the “Extended Lease Term”), upon the same terms and conditions of this Lease, except that Fixed Rent for the Extended Lease Term shall be at the Market Rent (as
determined below). Tenant shall notify Landlord, in writing, of its desire to exercise the Extension Option at least twelve (12) months prior to the Expiration Date (the “Tenant’s Notice”). Failure of Tenant to provide
notice within the time period required herein shall render Tenant’s Extension Option hereunder null and void and of no further force and effect. 
 2.
“Market Rent” shall be determined in accordance with the procedure set forth hereinafter: 
 A. The parties shall have
thirty (30) days after Landlord receives Tenant’s Notice in which to agree on the Market Rent for the Extended Term. If the parties agree on the Market Rent during such(30) day period, Landlord and Tenant shall execute an amendment to this
Lease setting forth the Market Rent for the Extended Term. 
 B. If the parties are unable to agree on the Market Rent within the thirty
(30) day period, then,within ten (10) days after the expiration of that period, each party, at its cost and by giving notice to the other party, shall appoint a qualified M.A.I. real estate appraiser with at least ten (10) years full
time commercial office appraisal experience in the Cambridge metropolitan area to appraise and set the Market Rent for the Premises. If a party does not appoint such an appraiser, the single appraiser appointed shall be the sole appraiser and shall
set the Market Rent for the Premises. The two appraisers appointed by the parties as stated in this paragraph shall meet promptly and attempt to establish the Market Rent for the Premises. If they are unable to agree within thirty (30) days
after the second appraiser has been appointed, they shall attempt to select a third appraiser meeting the qualifications stated in this paragraph within ten (10) days after the last day the two appraisers are given to set the Market Rent. If
they are unable to agree on the third (3rd) appraiser, either of the parties, by giving ten (10) days notice to the other party, can appeal to the then president of the Cambridge Real Estate
Board, for the selection of a third appraiser who meets the qualifications stated in this paragraph. Each of the parties shall bear one-half (1/2) of the cost of appointing the third appraiser and of paying
the third appraiser’s fee. The third appraiser, however selected, shall be a person who has not previously acted in any capacity for either party. 

C. Within thirty (30) days after the selection of the third appraiser, a majority of the appraisers shall set the Market Rent for the
Premises. If a majority of the appraisers are unable to set the Market Rent within the stipulated period of time, the three appraisals shall be added together and their total divided by three; the resulting quotient shall be the Market Rent for the
Premises. 
 D. If, however, the low appraisal and/or high appraisal are more than five percent (5%) lower and/or higher than the middle
appraisal, the low appraisal and/or high appraisal shall be disregarded. If only one appraisal is disregarded, the remaining two appraisals shall be added together and their total divided by two; the resulting quotient shall be the Market Rent for
the Premises. If both the low appraisal and the high appraisal are disregarded the middle appraisal shall be the Market Rent of the Premises. 

  
 F-1 

 E. “Market Rent” shall mean the economic terms at which tenants comparable
to Tenant, as of the first day of the applicable Extended Lease Term, are leasing in transactions for a comparable term, non-renewal, non-equity space comparable in size
to the Premises, from a willing, comparable landlord, at arm’s length, which comparable space is located in Comparable Buildings with similar amenities (“Comparable Transactions”), or, if such Comparable Buildings, or
comparable space within Comparable Buildings, is not available, adjustments shall be made in the determination of Market Rent to reflect the age and quality of the Building and Premises as contrasted to other buildings used for comparison purposes,
taking into consideration size, location, floor level, proposed term of the lease, extent of services to be provided, the time that the particular rate under consideration became or is to become effective, as well as all tenant concessions and
inducements. Additionally, in any determination of space within Comparable Buildings, appropriate consideration shall be given to the annual rental rates per rentable square foot, the standard of measurement by which the rentable square footage is
measured, and the ratio of rentable square feet to usable square feet. The intent of the parties is that Tenant will obtain the same rent and other economic benefits that landlords would otherwise give in Comparable Transactions and that Landlord
will make and receive the same economic payments and concessions that landlords would otherwise make and receive in Comparable Transactions. 

  
 F-2 

 EXHIBIT “G” 

BUILDING UPGRADES 
 1. As
of the Effective Date, Landlord is working to make improvements to the common areas of the Building for the benefit of all tenants in the Building and has or intends to make the following improvements in the Building at some point in the future (as
the “Building Upgrades”): 
  

	 	a.	Upgrading the restrooms on the fifth (5th), sixth (6th), and seventh (7th) floors of the Building according to Building Standard; and 

  

	 	b.	Renovating the lobby of the Building. 

 2. The restroom upgrades described in clause 1.a above will be
performed concurrently with Tenant’s construction of the Initial Improvements. Notwithstanding the foregoing, Landlord does not make any representations with respect to the date that any of the lobby renovations shall be completed (provided
that Landlord anticipates that Landlord’s lobby renovation will commence during the calendar year 2013). For purposes herein, “Building Standard” means work performed in the manner and with the materials selected by Landlord as
the existing standard for the Building subject to availability and Landlord’s right to select reasonable, alternative types, models, brands, grades, designs, manufacturers and suppliers from time to time as the Building Standard, so long as
such alternatives do not substantially or unreasonably deviate in quality, style or appearance as currently exists. 

  
 G-1 

 EXHIBIT “H” 

LEASE COMMENCEMENT DATE CERTIFICATE 
  

	RE:	Lease Agreement between KENDALL SQUARE ENTITY, INC. (“Landlord”) and TWITTER, INC., a Delaware corporation (“Tenant”) dated
                 (the “Lease”) for premises consisting of approximately 47,631 rentable feet in the building located at 141 Portland Street,
Cambridge, Massachusetts 

 Dear Tenant: 
 This
shall constitute the Lease Commencement Date Certificate referenced in Section 2 of the above-referenced Lease. Unless otherwise defined herein, all capitalized terms shall have the same meaning ascribed to them in the Lease. 

 

	1.	The Lease Commencement Date is                     . 

 

	2.	The Lease Expiration Date is                     . 

 

	3.	Fixed Rent shall be paid in accordance with the following schedule: 

 [NOTE: WHEN AVAILABLE, INSERT EXACT
DATES IN LEASE TERM COLUMN. DO NOT LEAVE AS IS] 
 *NOTE: Notwithstanding the schedule with respect to Fixed Rent set forth below, with respect
to the 5th Floor Premises and 6th Floor Premises, Tenant shall begin paying Fixed Rent on the one hundred eightieth (180th) day following the Lease Commencement Date. 
 *NOTE: Notwithstanding the schedule with respect to
Fixed Rent set forth below, with respect to the 7th Floor Premises, Tenant shall begin paying Fixed Rent on the Lease Commencement Date. 

[*] 

  
 H-1 

 IN WITNESS WHEREOF, the parties hereto have caused this Lease Commencement Date Certificate to be
executed on the dates set forth below. 
 LANDLORD: 

KENDALL SQUARE ENTITY, INC. 
 A Massachusetts corporation

  

			
		
	By:	 	 
	Name:	 	Peter Palandjian
	Title:	 	President & Treasurer

			
	Date of Execution:	 	 

 TENANT: 

TWITTER, INC. 
  

			
		
	By:	 	 
	Name:	 	 
	Title:	 	 

			
	Date of Execution:	 	 

  
 H-2 

 EXHIBIT “I” 

SATELLITE DISH TERMS AND CONDITIONS 
 1.
Location. Tenant shall have the right to install, operate, and maintain, at no additional cost to Tenant, one (1) satellite dish and related transmission equipment which specifications are subject to the prior written approval of
Landlord (collectively, the “Satellite Dish”) on the roof of the Building in a location mutually agreed to by Landlord and Tenant (such area to be known as the “Satellite Dish Area”). Landlord, at its
sole discretion, may require Tenant to relocate the Satellite Dish at any time to another location on the roof of the Building and for any reason provided Landlord pays for the reasonable cost of such relocation. 

2. Condition of Satellite Dish Area. The Satellite Dish Area is given to Licensee in its “as-is, where
is” condition. Licensor makes no representation or warranty that the Satellite Dish Area or Building is fit for Tenant’s intended use or permitted by law. Landlord shall have no obligation to prepare or otherwise repair the Satellite Dish
Area or the Satellite Dish. 
 3. Costs of Installation. Tenant shall pay, at its sole cost and expense, any and all expenses in connection
with installation of the Satellite Dish. Tenant shall obtain and pay, at its sole cost and expense, obtain any municipal, state or federal permits and/or licenses required for the installation and operation of the Satellite Dish and any related
equipment. 
 4. Roof Penetration and Warranty. Tenant shall not use or permit the use of the Satellite Dish in such a manner that would jeopardize
or invalidate Licensor’s existing roof warranty. In addition, Tenant shall use Landlord’s designated roof contractor when installing the Satellite Dish and Tenant shall be responsible for maintaining the Satellite Dish in a manner in which
to preserve such warranty. Any roof penetrations necessary in connection with the installation, maintenance or repair of the Satellite Dish are to be made by Landlord’s roof contractor, at Tenant’s sole cost and expense. 

5. Maintenance of Satellite Dish. Tenant, at its sole cost and expense, shall keep the Satellite Dish Area, Satellite Dish and all related equipment in
good condition and repair and shall be responsible for all maintenance and repair in connection with the Satellite Dish Area and the Satellite Dish. 
 6.
Access to Roof and Satellite Dish Area. Tenant and any of its agents or contractors shall not have access to the roof of the Building or the Satellite Dish Area unless Tenant has: (i) given Landlord at least twenty four (24) hours
advance notice; and (2) Tenant is accompanied by Landlord or its agent; and (3) such access occurs during normal Landlord’s normal business hours. 

7. Interference. Landlord shall use reasonable efforts to accommodate, Tenant, however, the Satellite Dish shall not be installed so as to interfere
with the use or operation of any communications equipment previously installed on the Building or the operations of any Tenant in the Building as of the Effective Date. Landlord shall not be responsible for any signal interference or signal straying
in connection with the Satellite Dish. 
 8. Tenant’s Rights Not Assignable. Tenant’s rights hereunder are personal to Tenant and may not
be assigned or transferred to any other party without the prior written consent of Landlord. 
 9. No Further Collocation. Tenant shall not permit
any other party to locate equipment in the Satellite Dish Area or collocate on the Satellite Dish without the prior written consent of Landlord. 

  
 I-1 

 10. Changes to Satellite Dish. Any changes to the Satellite Dish deviating from those originally
approved by Landlord must be reapproved by Landlord 
 11. Removal of Satellite Dish. Upon the expiration or earlier termination of the Lease, Tenant
shall remove the Satellite Dish and all related equipment leaving the Satellite Dish Area in the same condition existing on the Effective Date, reasonable wear and tear excepted. Tenant shall be responsible for the cost of repairing any and all
damage to the Satellite Dish Area, the roof of the Building, or any other areas of the Building in connection the installation, maintenance, repair, and/or operation of the Satellite Dish. 

  
 I-2 

 FIRST AMENDMENT TO LEASE AGREEMENT 

This FIRST AMENDMENT TO LEASE AGREEMENT (the “Amendment”) dated this 24th day of January, 2018 (the “Effective Date”)
is made by and between KENDALL SQUARE ENTITY, INC., a Massachusetts corporation (the “Landlord”), and TWITTER, INC., a Massachusetts corporation (the “Tenant”). 

RECITALS: 
 A. WHEREAS, Landlord and
Tenant are parties to that certain Lease Agreement dated as of September 10, 2013 (the “Lease”), whereby Tenant leases certain premises from Landlord of approximately: (i) 15,877 rentable square feet on the fifth (5th) floor
(“5th Floor Premises”); (ii) approximately 15,877 rentable square feet on the sixth (6th) floor (“6th Floor Premises”); and (iii) approximately 15,877 rentable square feet on the seventh (7th) floor (“7th Floor Premises”) (collectively, the “Existing Premises”) in the building located at 141 Portland Street, Cambridge, Massachusetts (the “Building”); 

B. WHEREAS, the Lease Term with respect to the Existing Premises is scheduled to expire on March 31, 2019; and 

C. WHEREAS, Tenant desires to extend the Lease Term with respect to the 5th Floor Premises and 6th Floor Premises (the “Remaining Premises”) and Landlord desires to accommodate the same on the terms and conditions set forth herein. 

AGREEMENT: 
 NOW THEREFORE, in
consideration of the promises contained herein and other good and valuable consideration, the receipt of which is hereby acknowledged, the parties agree as follows: 

1. Recitals and Capitalized Terms. The recitals set forth above are incorporated herein and made a part of this Amendment as if set forth herein in
full. All capitalized terms used in this Amendment that are not defined in this Amendment shall have the meanings ascribed to such terms in the Lease. In the event of any conflict between the terms of the Lease and the terms of this Amendment, the
terms set forth in this Amendment shall supersede and control. 
 2. Lease Term for Remaining Premises. The Lease Term with respect to the Remaining
Premises shall be extended through March 31, 2024 (the “Extended Expiration Date”, and such extended portion of the Lease Term, the “Extension Term”). Effective as of April 1, 2019, the Remaining Premises
shall be known as the “Premises” for purposes under the Lease. 

  
 1 

 3. Fixed Rent for Remaining Premises. During the Extension Term, Tenant shall pay Fixed Rent with
respect to the Remaining Premises in accordance with the schedule below but otherwise in accordance with the terms and conditions of the Lease: 
  

							
		 	 Annual Fixed Rent
	  	 Monthly Fixed Rent
	  	 Fixed Rent Per

Square Foot of

Remaining Premises

	[*]	 	[*]	  	[*]	  	[*]

 4. Additional Rent. 

4.1 Tenant’s Proportionate Share. Effective on April 1, 2019, Tenant’s Proportionate Share shall be amended to be 23.37%
which is based on 31,754 rentable square feet in the Remaining Premises and 135,874 rentable square feet in the Building. 
 4.2
Operating Expense Stop and Tax Expense Stop. During the Extension Term, Tenant shall continue to pay Additional Rent in accordance with the terms and conditions of the Lease, provided, however, that effective on April 1, 2019: (a) the
“Operating Expense Stop” shall be amended to mean an amount equal to the actual Operating Expenses (on a per rentable square foot basis, adjusted, as necessary, as described in Section 3 of Exhibit C to the Lease) for the
calendar year 2019; and (b) the “Tax Expense Stop” shall mean an amount equal to the actual Taxes (on a per rentable square foot basis) for the fiscal year 2020. 

5. Condition of Premises. Except for the Improvement Allowance as further described on EXHIBIT A, Tenant’ shall continue to occupy the
Remaining Premises during the Extension Term in its “as-is” condition and Landlord shall not be obligated for any other allowances or improvements to the Remaining Premises; the foregoing will not be
deemed to modify or diminish Landlord’s maintenance and repair obligations set forth in the Lease. 
 6. Parking. Effective as of the
April 1, 2019, SECTION 30. PARKING of the Lease shall be deleted in its entirety and replaced with the following: 
 30.
PARKING. Tenant shall lease thirty-two (32) assigned parking spaces at the rate of two hundred seventy five dollars ($275.00) per space per month, which amount is subject to change on an annual basis
(consistent with the rates charged to all other users of the parking facility), for the parking of registered and insured passenger vehicles (excluding trucks) of its own (or its subtenants) or of its (or its subtenants) employees in the parking
garage area of the Building. In addition, Tenant shall pay to Landlord the amount of seventy-five dollars ($75.00) for each parking transmitter that Tenant requests to access the parking facilities, which amount shall be returned to Tenant upon
expiration 

  
 2 

	 	
of this Lease provided the transmitters are returned to Landlord in the condition as they were originally provided to Tenant, reasonable wear and tear excepted. All such parking rights shall be
subject to the reasonable rules and regulations of Landlord of general applicability; provided however, Landlord shall have no duty to enforce the same, and shall have the right to waive the applicability of the same on a case by case basis, in its
sole discretion. All such parking and use of the lot for access and egress shall be at the user’s sole risk, and Landlord shall not be responsible for any property damage or loss or any personal injury related thereto, except for any personal
injury proximately caused by the negligence or willful misconduct of Landlord. Tenant shall inform any of its employees or agents (or subtenants) utilizing such parking right of the aforesaid limitation of liability, and Tenant shall indemnify
Landlord, its managing agent and their employees or agents, defend them and hold them harmless against any claim, suit, judgment, or loss (relating to the use of the parking lights herein granted) suffered by them or instituted against them which is
included within the aforesaid limitation of liability. Landlord shall be responsible for snow removal/plowing of the parking areas; provided however, in the event vehicles are present in the said areas during snow removal activities, Landlord will
plow around such vehicles and shall not be required to remove any residue of snow surrounding the vehicle as a result of such plowing activity. Upon Landlord’s request Tenant and its employees shall relocate temporarily any of its or their
vehicles parked in the parking area in order to facilitate snow removal or maintenance activity being conducted by Landlord. Such parking by Tenant (or Tenant’s subtenants) or its (or Tenant’s subtenants) employees shall be assigned as to
location, No overnight parking is permitted by Tenant or its employees without Landlord’s specific prior written authorization. 

 7.
Deletion of Extension Option. EXHIBIT “F” EXTENSION OPTION of the Lease is hereby deleted in its entirety and of no further force and effect. 

8. Letter of Credit. [*] 
 9. Surrender of 7th Floor Premises. Not later than March 31, 2019, Tenant shall have surrendered the 7th Floor Premises to Landlord in accordance
with SECTION 25. SURRENDER OF PREMISES of the Lease (i.e., in its current “as-is” condition free of Tenant’s and subtenants’ personal property, furniture and equipment). 

10. Brokers. Each party represents and warrants to the other that they have not made any agreement or taken any action which may cause anyone to become
entitled to a commission as a result of the transactions contemplated by this Amendment and each will indemnify and defend the other from any and all claims, actual or threatened, for compensation by any such third person by reason of such
party’s breach of their representation or warranty contained in this Section 10 except for Transwestern RBJ representing Landlord exclusively (“Landlord’s Broker”) and Cresa, representing Tenant exclusively
(“Tenant’s Broker”). Landlord will pay any commission due to Landlord’s Broker and Tenant’s Broker hereunder pursuant to its separate agreement with Landlord’s Broker. 

  
 3 

 11. Tenant’s Representations. Tenant hereby represents and warrants to Landlord that as of the
Effective Date: (a) all of Tenant’s estate, right, title and interest in and to the Lease is free and clear of assignments or liens; (b) the Lease is in full force and effect; (c) Tenant is presently in possession of the Premises
(however, Tenant may from time to time have one or more subtenants in occupancy of a portion or portions of the Premises) and is paying the Fixed Rent, Additional Rent and any other charges or sums due under the Lease with respect to the Existing
Premises; (d) the Lease has not been modified, supplemented or amended in any way, except as may be set forth in this Amendment; (e) Tenant is not aware of any current actionable defenses, claims or
set-offs under the Lease against rents or charges due or to become due thereunder; and (f) that this Amendment has been duly authorized, executed and delivered by and on behalf of Tenant and constitutes
the valid and binding agreement of Tenant in accordance with the terms hereof. 
 12. Landlord’s Representatives. Landlord hereby represents and
warrants to Tenant that as of the Effective Date: (a) no Event of Default on the part of Tenant exists under the Lease and no event which, with notice or the passage of time on the part of Tenant, would constitute an Event of Default under the
Lease currently exists and (b) the Lease is in full force and effect and (c) this Amendment has been duly authorized, executed and delivered by and on behalf of Landlord and constitutes the valid and binding agreement of Landlord in
accordance with the terms hereof. 
 13. Confirmation of Lease. Except as amended by this Amendment, all existing terms and provisions of the Lease
shall remain in full force and effect. 
 [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK] 

[SIGNATURE PAGE TO FOLLOW] 

  
 4 

 IN WITNESS WHEREOF, Landlord and Tenant have caused this Amendment to be executed as of the Effective Date.

 LANDLORD: 
  

			
	 KENDALL SQUARE ENTITY,INC.
 A
Massachusetts corporation

		
	By:	 	/s/ Peter Palandjian
	Name:	 	Peter Palandjian
	Title:	 	President & Treasurer

 TENANT: 
  

			
	 TWITTER, INC.
 a Delaware
corporation

		
	By:	 	/s/ Ned Segal
	Name:	 	Ned Segal
	Title:	 	CFO

  
 5 

 EXHIBIT A 

IMPROVEMENT ALLOWANCE 
 1.
Landlord shall provide to Tenant an allowance of [*] per rentable square foot of the Remaining Premises (i.e., $[*]) (the “Improvement Allowance”) which shall be applied by Tenant toward the cost of design, permitting and
construction costs, architectural, engineering and project management costs associated with improvements made by Tenant to the Remaining Premises commencing from and after the Effective Date (the “Tenant Improvements”).
Notwithstanding the foregoing, Tenant shall not be permitted to apply more than $158,770.00 of the Improvement Allowance toward “soft costs” associated with the Tenant Improvements. Tenant acknowledges that all costs for Tenant
Improvements in excess of the Improvement Allowance shall be paid for at the sole cost and expense of the Tenant. 
 2. The Tenant Improvements shall be
shall be subject to: (a) all terms and conditions of Section 10 of the Lease; (b) performed by a union general contractor reasonably approved by Landlord in advance; and (c) based on plans and specifications reasonably approved
(or deemed approval, as described in Section 10.1 of the Lease) by Landlord in advance. 
 3. Landlord shall disburse the Improvement Allowance to
Tenant on a periodic basis (but no more than once per month) within thirty (30) days following receipt from Tenant of a Requisition from Tenant. A “Requisition” shall mean written documentation, including, without limitation,
(i) invoices from Tenant’s contractors, vendors, service providers and consultants, and such other documentation as Landlord may reasonably request, showing in reasonable detail the cost of the items in question or improvements installed
to date in the Premises, accompanied by certifications from Tenant that the amount of the Requisition in question is true and correct and does not exceed the cost of the items or improvements covered by such Requisition (AJA Form G-702 is deemed acceptable by Landlord as a requisition form); and (ii) evidence that all of the Tenant Improvements and other work done by or on behalf of Tenant as of such date which could give rise to any
mechanic’s or materialman’s liens and for which payment has been previously requested and paid, has been paid for in full and that any and all liens therefor that have been or may be filed have been satisfied of record or waived (the
“Lien Waivers”) with respect to the prior month’s Requisition. Landlord shall have the right, upon reasonable advance notice to Tenant, to inspect Tenant’s books and records relating to each Requisition in order to verify
the amount thereof. For avoidance of doubt, as of the Effective Date, Tenant may submit a Requisition for Tenant Improvements constructed at any time following the Effective Date, Notwithstanding the foregoing, at Tenant’s election, Tenant may
elect to wait until the completion of the Tenant Improvements before submitting a single Requisition for all of the Improvement Allowance to Landlord, provided that such Requisition includes all of the information required by the provisions of this
Section 3. 
 4. Landlord shall have no obligation to pay any portion of the Improvement Allowance with respect to any Requisition submitted more than
twelve (12) months following the Effective Date (the “Outside Requisition Date”); provided, however, that (i) the Outside Requisition Date shall be delayed on a day-for-day basis for each day that Tenant’s design or construction of Tenant’s Improvements is delayed due to Force Majeure or the acts or omissions of Landlord and (ii) if Tenant certifies to
Landlord that it is engaged in a good faith dispute with a contractor, vendor,service provider or consultant, such Outside Requisition Date shall be extended while such 

  
 6 

 
dispute is ongoing, so long as Tenant is diligently pursuing the resolution of such dispute. In the event Tenant has not utilized the Improvement Allowance on or before the Outside Requisition
Date, Tenant shall be deemed to have forfeited any unused portion of said Improvement Allowance and shall have no rights thereto, 

  
 7EX-10.21

 Exhibit 10.21 

LEASE AGREEMENT 
 THIS
LEASE AGREEMENT (this “Lease”) is made as of this 22nd day of December 2017, between ARE-MA REGION NO. 59, LLC, a Delaware limited liability company (“Landlord”), and
SOLID BIOSCIENCES, LLC, a Delaware limited liability company (“Tenant”). 
 BASIC LEASE PROVISIONS 

 

			
	Address of Building:	  	Building 1400, One Kendall Square, Cambridge, MA 02139

			
		
	Premises:	  	That portion of the Building in the Project (as defined below) commonly known as Suite 14-101 located on the first floor of the Building, containing approximately 9,489 rentable square feet,
as shown on Exhibit A.
		
	Building:	  	The building in the Project currently known and numbered as 1400, One Kendall Square, Cambridge, Massachusetts, and located on the real property owned by Landlord and described on Exhibit B (the
“Property”).
		
	Project:	  	The project commonly known as One Kendall Square, located on the Property and property owned by affiliates of Landlord and operated as a single mixed-use complex.
		
	Base Rent:	  	$75.00 per rentable square foot of the Premises per year, subject to adjustment as provided in Section 4 below.

 Rentable Area of Premises: 9,489 rentable square feet 

Rentable Area of Project: 644,771 rentable square feet 

Rentable Area of Building: 133,989 rentable square feet 

Building’s Share of Project: 20.78% 

Tenant’s Share: 7.08% 
 Security Deposit:
$237,225.00  
 Target Commencement Date: February 1, 2018 

Rent Commencement Date: As defined in Section 2 below. 

 

			
	Rent Adjustment Percentage:	  	3%
		
	Base Term:	  	Beginning on the Commencement Date and ending 60 months from the first day of the first full month following the Rent Commencement Date, or if the Rent Commencement Date occurs on the first day of a month, from the first day of the
month containing the Rent Commencement Date.
		
	Permitted Use:	  	Research and development laboratory, related office and other related uses consistent with the character of the Project and otherwise in compliance with the provisions of Section 7 hereof.

  

			
	

	  	 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.

			
	Multi-Tenant Laboratory	 	 1400 One Kendall Square/Solid Biosciences – Page
 2

  

			
	Address for Rent Payment:	  	Landlord’s Notice Address:
	ARE-MA Region No. 59, LLC	  	385 East Colorado Boulevard, Suite 299
	P.O. Box 944193	  	Pasadena, CA91101
	Cleveland, OH 44194-4193	  	Attention: Corporate Secretary
		  	
	Tenant’s Notice Address:	  	
	One Kendall Square, Building 1400	  	
	Suite 14-101	  	
	Cambridge, MA 02139	  	

 Attention: Lease Administrator 

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

 

			
	[X] EXHIBIT A - PREMISES DESCRIPTION	  	[X] EXHIBIT B - DESCRIPTION OF PROPERTY
	[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 - NOTIFICATION OF PRESENCE	  	
	OF ASBESTOS CONTAINING MATERIALS	  	

 1. Lease of Premises. Upon and subject to all of the terms and conditions of this Lease, 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 Building are collectively referred to herein
as the “Common Areas.” Subject to the terms and conditions of this Lease, Tenant shall have the appurtenant right to use the Common Areas for their intended uses. The Common Areas shall include, without limitation, the common
loading areas located in and serving the Building, pedestrian sidewalks and landscaped areas serving the Project, as well as the common elevators, lobbies, hallways, corridors and stairwells and, if applicable, restrooms, within the Building and
serving the Premises or necessary for access to and use of the Premises. In addition to other rights reserved herein or by law, Landlord reserves the right from time to time, without material interruption of Tenant’s use and access to the
Premises (except in emergency): (i) to make additions to or reconstructions of the Building, Property and Project and to install, use, maintain, repair, replace and relocate for service to the Premises or other parts of the Building, Property and/or
Project, pipes, ducts, conduits, wires and appurtenant fixtures, wherever located in the Premises, the Building, the Property or elsewhere in the Project, including without limitation, the installation of such facilities in the plenums of the
ceilings of the Premises (or, if there is no drop ceiling, within the space above 10 feet of any floor of the Premises), and coring therefor between the ceiling or top surface of any portion of the Premises, and the space above the Premises in the
plenum or below the top of the Premises as aforesaid; and (ii) to alter or relocate any Common Area or facility. 
 From and after the
Commencement Date through the expiration of the Term, Tenant shall have access to the Building and the Premises 24 hours a day, 7 days a week, except in the case of emergencies, as the result of Legal Requirements, the performance by Landlord of any
installation, maintenance or repairs, or any other temporary interruptions, and otherwise subject to the terms of this Lease. 
 2.
Delivery; Acceptance of Premises; Commencement Date. Landlord shall use reasonable efforts to make the Premises available to Tenant for Tenant’s work on the Tenant Improvements under the Work Letter (“Delivery” or
“Deliver”) on or before the Target Commencement Date. If Landlord fails to timely Deliver the Premises, Landlord shall not be liable to Tenant for any loss or damage resulting therefrom, and this Lease shall not be void or voidable
except as provided herein. If Landlord does not Deliver the Premises within 60 days of the Target Commencement Date for any reason other than delays due to Force Majeure (as defined in Section 34 below), this Lease may be
terminated by Tenant by written notice to Landlord, and if so terminated by Tenant: (a) 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; and (b) neither Landlord nor Tenant shall have any further rights, duties or obligations under this Lease, except with respect to provisions which expressly survive termination of this Lease. As used herein, the
term “Tenant Improvements” shall have the meaning set forth for such term in the Work Letter. If Tenant does not elect to void this Lease within 10 business days of the lapse of such 60 day period, such right to void this Lease
shall be waived and this Lease shall remain in full force and effect. 

  

			
	

	  	 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.

			
	Multi-Tenant Laboratory	 	 1400 One Kendall Square/Solid Biosciences – Page
 3

  

 The “Commencement Date” shall be the date Landlord Delivers the Premises to
Tenant. The “Rent Commencement Date” shall be the earlier of (i) 5 months after the Commencement Date, or (ii) the date Tenant conducts any business in the Premises or any part thereof (not including the construction of the
Tenant Improvements in 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, the failure by either party to execute and deliver such acknowledgment shall not affect either party’s rights
or the Commencement Date hereunder. The “Term” of this Lease shall be the Base Term, as defined above in the Basic Lease Provisions and the Extension Term which Tenant may elect pursuant to Section 39
hereof. 
 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) serving the Premises, unless Tenant or any Tenant Party was
responsible for the cause of such repair, in which case Tenant shall pay the cost. 
 Except as set forth 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) except as provided in the immediately preceding
paragraph, 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. 

Notwithstanding anything to the contrary contained in this Lease, Tenant and Landlord acknowledge and agree that the effectiveness of this
Lease shall be subject to the following condition precedent (“Condition Precedent”) having been satisfied: Landlord shall have entered into a lease termination agreement on or before January 30, 2018 (“Termination
Agreement”) with the existing tenant of the Premises which Termination Agreement shall be on terms and conditions acceptable to Landlord, in Landlord’s sole and absolute discretion. In the event that the Condition Precedent is not
satisfied, either Landlord or Tenant shall have the right to terminate this Lease upon delivery of written notice to the other. Landlord shall have no liability whatsoever to Tenant relating to or arising from Landlord’s inability or failure to
cause the Condition Precedent to be satisfied. 
 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. The first full calendar month’s Base Rent 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 from and after the Rent Commencement Date, in lawful money of the United
States of America, at the office of Landlord for payment 

  

			
	

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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. If the Rent Commencement Date is other than the first day of a calendar month, the difference between the first full calendar month’s Base Rent paid upon delivery of an executed copy of this Lease by Tenant to Landlord as required
above, and the prorated Base Rent for the fractional month in which the Rent Commencement Date occurs, shall be applied by Landlord to such first full calendar month after the Rent Commencement Date and Tenant shall pay the remainder of the first
full calendar month’s rent to Landlord on or before the first day of such first full calendar month. The obligation of Tenant to pay Base Rent, Additional Rent and any 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. 
 (b) Additional Rent. 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. 
 4. Base Rent Adjustments. Base
Rent shall be increased on each annual anniversary of the first day of the first full month during the Term of this Lease (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. 
 5. Operating Expense Payments. At least 30 days prior to the beginning of each calendar year, Landlord
shall deliver to Tenant a written estimate of Operating Expenses for the upcoming calendar year during the Term (the “Annual Estimate”), which may be revised by Landlord from time to time during such calendar year. Commencing on the
Rent Commencement Date and continuing thereafter on the first day of each month during the Term, 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 in accordance with Landlord’s (and Landlord’s affiliates) regular accounting practices with respect to the Building and Property (including, without duplication, the Building’s Share of Project
with respect to 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 Property or any other building or property located in the Project) including,
without duplication or limitation, (w) Taxes (as defined in Section 9), (x) capital repairs, replacements and improvements amortized over the lesser of 10 years or the useful life of such capital items (except for
capital repairs, replacements and improvements to the roof, which shall be amortized over 15 years), adjusted to reflect Building operations 24 hours per day, 7 days per week and 365 days per year (provided that those Operating Expenses incurred or
accrued by Landlord with respect to any capital repairs, replacements or improvements which are for the intended purpose of promoting sustainability (for example, without limitation, by reducing energy usage at the Project) (a “Capital
Sustainability Expenditure”) may be amortized over a shorter period, at Landlord’s discretion, to the extent the cost of a Capital Sustainability Expenditure is offset by a reduction in Operating Expenses), (y) transportation services,
and (z) the costs of Landlord’s third party property manager (not to exceed 3% of Base Rent) or, if there is no third party property manager, administration rent in the amount of 3% 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; 

  

			
	

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 (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 and all payments of base rent (but not taxes or operating expenses) under any ground lease or other underlying lease of all or any portion of the Project; 

(d) depreciation of the Project (except for capital improvements, the costs 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; 

(g) completing, permitting, 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; provided, however, that with respect to any such person who does
not devote substantially all of his or her employed time to the Project, the salaries, wages, benefits and other compensation of such person shall be prorated to reflect time spent on matters related to operating, managing, maintaining or repairing
the Project in comparison to the time spent on matters unrelated to operating, managing, maintaining or repairing 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 or Property; 
 (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; 

  

			
	

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 (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 Property or Project; 

(r) net income taxes of Landlord or the owner of any interest in the Property or Project, franchise, capital stock, gift, estate or
inheritance taxes or any federal, state or local documentary taxes imposed against the Property or Project or any portion thereof or interest therein; 

(s) any expenses otherwise includable within Operating Expenses to the extent actually reimbursed by insurance policies required to be
maintained by Landlord in accordance with Section 17 (or, if Landlord fails to maintain the insurance required to be carried by Landlord pursuant to Section 17, would have been reimbursed by insurance required
to be carried by Landlord pursuant to Section 17); 
 (t) any costs incurred to remove, study, test or remediate
Hazardous Materials in or about the Premises, the Building or the Project for which Tenant is not responsible under Section 30 hereof; 

(u) 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 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 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 a regionally recognized independent public accounting firm selected by Tenant and approved by Landlord (which approval shall not be unreasonably withheld, conditioned 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

  

			
	

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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’s Share” shall be the percentage set forth in the Basic Lease Provisions as Tenant’s Share, and
“Building’s Share of Project” shall be the percentage set forth in the Basic Lease Provisions as the Building’s Share of Project, each as may be reasonably adjusted by Landlord upon a measurement of the rentable square
footage of the Premises, Building, Property and/or Project done by Landlord, if Landlord so elects, within 90 days of the Commencement Date, or as soon as reasonably possible thereafter, and shall be subject to further adjustment for changes in the
physical size of the Premises, Building, Property or 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 Building, Property or Project that includes the Premises or that varies with occupancy or use. Landlord may equitably increase the Building’s Share of Project for any item of expense or cost
reimbursable by Tenant that relates to a repair, replacement, or service that benefits only the Building or only a portion of the Property or Project that includes the Building or that varies with occupancy or use of the Building. 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.” 

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 in the Basic Lease Provisions, 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 reasonably 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 10 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, 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. Upon any such 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 in the Basic Lease
Provisions. 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. Upon any such use of all or any portion of the Security Deposit, Tenant shall, within 10 days after demand from Landlord, restore the Security Deposit to its original amount. If Tenant

  

			
	

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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 60 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. 
 7. Use. 

(a) Tenant’s Use. The Premises shall be used solely for the Permitted Use set forth in the Basic Lease Provisions, 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 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 Building or in the Building elevators without the prior written consent of Landlord. Except as may be provided under the Work Letter, 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 Building as proportionately allocated to the
Premises based upon Tenant’s Share as usually furnished for the Permitted Use. 
 Landlord shall 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 or occupancy of the Premises or Tenant’s
Alterations) make any alterations or modifications to the Common Areas or the exterior of the Building (including structural obligations or modifications) that are required by Legal Requirements. Except as provided in the two 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

  

			
	

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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 Tenant Improvements or any Tenant Alterations. 
 (b)
Energy Use Reporting. Tenant agrees to provide, within 10 business days of request by Landlord, such information and documentation as may be needed for compliance with the City of Cambridge Building Energy Use Disclosure Ordinance,
Section 8.67.010 et seq. of the Municipal Code of the City of Cambridge (as the same may be amended, the “Cambridge Building Energy Use Disclosure Ordinance”), and other such energy or sustainability requirements as may be
adopted from time to time by the City of Cambridge or any other governmental authority with jurisdiction over the Building, which information shall include without limitation usage at or by the Premises of electricity, natural gas, steam, hot or
chilled water or other energy. Landlord shall report to the applicable governmental authority such energy usage for the Building and other Building information as required by the Cambridge Building Energy Use Disclosure Ordinance. 

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 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, 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 Building, Property or 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, Building, Property or Project or portion thereof, or (iii) assessed or imposed by or on the operation or maintenance of any portion of the Premises, Building, Property or 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

  

			
	

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or assessment on Landlord’s business or occupation of leasing space in the Building, Property or Project or portion thereof. 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. Operating Expenses hereunder shall also include the cost of tax monitoring
services provided to Landlord with respect to the Building, Property or Project. 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 Building, Property or 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 Building, Property or Project, or portion thereof of which the Premises are a part, Landlord shall have the right, but not
the obligation, to pay such Taxes. Landlord’s reasonable 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 and PTDM. 

(a) Parking and Monthly Parking Charge. Subject to all matters of record, Force Majeure, a Taking (as defined in
Section 19 below), the exercise by Landlord of its rights hereunder and upon payment of the Monthly Parking Charge (as defined below) for each parking space commencing on the Rent Commencement Date, Tenant shall have the
right, in common with other tenants of the Project to use 1.0 vehicle parking spaces per 1,000 rentable square feet of the Premises (“Tenant’s Parking Allowance”) in the parking facility located at the One Kendall Square Garage
located on Binney Street (the “OKS Garage”) to park in those areas designated for non-reserved parking, subject in each case to Landlord’s reasonable rules and regulations; provided,
however, Landlord may relocate any or all of Tenant’s Parking Allowance from the OKS Garage to another parking facility in close proximity to the OKS Garage (i.e., being within 0.25 miles of the OKS Garage). If, during the Term, Tenant delivers
written notice to Landlord requesting additional parking spaces and Landlord determines that the additional parking spaces desired by Tenant are available for use by Tenant, Landlord shall notify Tenant in writing and Tenant shall commence using and
paying the Monthly Parking Charge for such additional parking spaces immediately following Landlord’s delivery of such written notice to Tenant that such additional parking spaces are available for Tenant’s use. Landlord shall not be
responsible for enforcing Tenant’s parking rights against any third parties, including other tenants of the Project. The “Monthly Parking Charge” shall mean the market rate monthly charge therefor designated by Landlord,
adjusted reasonably and no more frequently than once in any 12-month period, based upon the rates charged by comparable parking facilities in the vicinity of the Project, which as of the date of this Lease
such Monthly Parking Charge is equal to $325.00 per space per month, plus applicable taxes. 
 (b) Parking and Transportation Demand
Management. Tenant shall, at Tenant’s sole expense, for so long as a parking and traffic demand management plan approved by the City of Cambridge (as amended from time to time, the “PTDM”), is applicable to the Project,
comply with the PTDM as applicable to the Project, including without limitation, as applicable (i) offer to subsidize mass transit monthly passes for all of its employees who work in the Premises in accordance with the terms set forth in the
PTDM; (ii) implement a Commuter Choice Program and the MBTA’s Corporate Pass Plan; (iii) discourage single-occupant vehicle (“SOV”) use by its employees; (iv) promote alternative modes of transportation and use
of alternative work hours; (v) at Landlord’s request, meet with Landlord and/or its representatives no more frequently than quarterly to discuss transportation programs and initiatives; (vi) participate in annual surveys, monitoring
transportation programs and initiatives at the Campus, and, without limitation, achieve a sixty (60%) percent response rate for patron surveys; (vii) cooperate with Landlord in connection with transportation programs and initiatives promulgated
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(viii) provide alternative work programs (such as telecommuting, flex-time and compressed work weeks) to its employees in order to reduce traffic impacts in Cambridge during peak commuter hours;
(ix) offer an emergency ride home (“ERH”) through the Charles River Transportation Management Association (“CRTMA”), or have its own ERH program, for all employees who commute by
non-SOV mode at least 3 days a week and who are eligible to park in the parking spaces in the parking facility described above; (x) cooperate with the Cambridge Office of Workforce Development to expand
employment opportunities for Cambridge residents; (xi) become a member of the CRTMA and cause the EZ Ride shuttle service to service the Building; (xii) in the event that the single occupancy vehicle and traffic generation modal split
limits of the PTDM are exceeded, charge each user of a parking space the market rate for parking in Kendall Square/East Cambridge therefor; (xiii) comply with the requirements of any other parking and traffic demand management plan to which
Tenant may be a party from time to time; (xiii) designate an employee transportation coordinator for the Building; and (xiv) otherwise cooperate with Landlord in encouraging employees to seek alternate modes of transportation. 

11. Utilities, Services. 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 Building is plumbed for such services), and 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, 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 any taxes, penalties, surcharges or similar charges thereon. The Premises shall be separately metered to measure Tenant’s usage of electricity for lights and plugs. 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, shall result in eviction or constructive eviction of Tenant, termination of this Lease or, except as otherwise expressly provided in the immediately following paragraph, the abatement of Rent. Tenant agrees to
limit use of water and sewer with respect to Common Areas to normal restroom use. 
 Notwithstanding anything to the contrary set forth
herein, if (i) a stoppage of an Essential Service (as defined below) to the Premises shall occur and such stoppage is due solely to the gross negligence or willful misconduct of Landlord and not due in any part to any act or omission on the
part of Tenant or any Tenant Party or any matter beyond Landlord’s reasonable control (any such stoppage of an Essential Service being hereinafter referred to as a “Service Interruption”), and (ii) such Service
Interruption continues for more than 3 consecutive business days after Landlord shall have received written notice thereof from Tenant, and (iii) as a result of such Service Interruption, the conduct of Tenant’s normal operations in the
Premises are materially and adversely affected, then there shall be an abatement of one day’s Base Rent for each day during which such Service Interruption continues after such 3 business day period; provided, however, that if any part of the
Premises is reasonably useable for Tenant’s normal business operations or if Tenant conducts all or any part of its operations in any portion of the Premises notwithstanding such Service Interruption, then the amount of each daily abatement of
Base Rent shall only be proportionate to the nature and extent of the interruption of Tenant’s normal operations or ability to use the Premises. The rights granted to Tenant under this paragraph shall be Tenant’s sole and exclusive remedy
resulting from a failure of Landlord to provide services, and Landlord shall not otherwise be liable for any loss or damage suffered or sustained by Tenant resulting from any failure or cessation of services. For purposes hereof, the term
“Essential Services” shall mean the following services: HVAC service, water, sewer and electricity, but in each case only to the extent that Landlord has an obligation to provide same to Tenant under this Lease. 

Landlord’s sole obligation for either providing emergency generators or providing emergency backup 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
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guidelines. Except as otherwise provided in the immediately preceding sentence, 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 acknowledges and agrees that (x) in connection
with the proper verification of loads and maintenance of the emergency generators, that power will need to be transferred during routine testing, and (y) Tenant is responsible for cooperating with Landlord or Landlord’s third party
contractor with respect to scheduling such routine tests and checking its own equipment loads as it operates during load transfer periods. 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. 
 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, but which shall otherwise not be unreasonably withheld or delayed. Tenant may construct nonstructural, cosmetic Alterations in the Premises that will not affect the operation of any Building Systems, without Landlord’s prior
approval if the aggregate cost of all such work in any 12 month period does not exceed $25,000.00 (excluding paint and carpet/floor coverings) (a “Notice-Only Alteration”), provided Tenant notifies Landlord in writing of such
intended Notice-Only Alteration, and such notice shall be accompanied by plans, specifications, work contracts and such other information concerning the nature and cost of the Notice-Only Alteration as may be reasonably requested by Landlord, which
notice and accompanying materials shall be delivered to Landlord not less than 15 business days in advance of any proposed construction. 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 reasonable 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 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 the reasonable out-of-pocket costs incurred by Landlord 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 reasonably 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) to the extent available, “as built” plans for any
such Alteration. 

  

			
	

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 Other than (i) the items, if any, listed on Exhibit F attached hereto,
(ii) any items agreed by Landlord in writing to be included on Exhibit F in the future, and (iii) any trade fixtures, machinery, equipment and other personal property not paid for out of the TI Fund (as defined in the Work Letter)
which may be removed without material damage to the Premises, which damage shall be repaired (including capping or terminating utility hook-ups behind walls) by Tenant during the Term (collectively,
“Tenant’s Property”), all property of any kind paid for with the TI Fund, all Alterations, real property fixtures, built-in machinery and equipment,
built-in casework and cabinets and other similar additions and improvements built into the Premises so as to become an integral part of the Premises, such as 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 (collectively,
“Installations”) 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 in accordance with Section 28 following the expiration or earlier termination of this Lease; provided, however, that Landlord shall, at the time its
approval of such Installation is requested notify Tenant if it has elected to cause Tenant to remove such Installation upon the expiration or earlier termination of this Lease. If Landlord so elects, Tenant shall remove such Installation upon the
expiration or earlier termination of this Lease and restore any damage caused by or occasioned as a result of such removal, including, when removing any of Tenant’s Property which was plumbed, wired or otherwise connected to any of the Building
Systems, capping off all such connections behind the walls of the Premises and repairing any holes. During any such restoration period, Tenant shall pay Rent to Landlord as provided herein as if said space were otherwise occupied by Tenant. 

13. Landlord’s Repairs. Landlord, as an Operating Expense, shall maintain all of the structural, exterior, parking and other
Common Areas of the Building and Property, including HVAC, plumbing, fire sprinklers, elevators and all other building systems serving the Premises and other portions of the Building (“Building 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 24 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 (or with respect to any emergency, oral notice followed immediately by written notice), after
which Landlord shall have a reasonable opportunity 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, reasonable wear and tear and damage by fire or other
casualty excepted. Should Tenant fail to make any such repair or 

  

			
	

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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 30 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 30 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 Building, Property or Project for work claimed to have been done for, or materials claimed to have been furnished to, Tenant within 20 days after Tenant receives notice of the filing thereof, at Tenant’s sole cost and shall otherwise keep
the Premises and the Building, Property and 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 Building, Property or 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 Building or 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, its officers, directors, employees,
managers, agents, sub-agents, constituent entities and lease signators (collectively, “Landlord Indemnified Parties”) and Holders of Mortgages (each as defined in
Section 27 below) as to which Tenant has been given notice 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 the use or occupancy of the Premises by Tenant or any Tenant Parties 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 Indemnified Parties. Landlord Indemnified Parties shall not be 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
hereby irrevocably 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 Indemnified Parties
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 Building. 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 Building and Property may be included in a blanket policy (in which
case the cost of such insurance allocable to the Building and Property 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. 

  

			
	

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 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,
sub-agents, constituent entities and lease signators (collectively, “Landlord Insured 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 30 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 Insured Parties (any policy issued to Landlord
Insured Parties providing duplicate or similar coverage shall be deemed excess over Tenant’s policies, regardless of limits). 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 upon commencement of the Term and upon 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 Building, Property or Project or any portion thereof and any
servicer in connection therewith, (ii) the landlord under any lease wherein Landlord is tenant of the real property on which the Building, Property or 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 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, Building, Property or 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 Building or the Premises are damaged or destroyed by a fire or other insured 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 Building or the Premises, as applicable (the “Restoration Period”). If the Restoration Period is estimated to exceed 

  

			
	

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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 re-enter 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 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. In the event that no Hazardous Material Clearances are required to be obtained by Tenant with respect to the Premises, rent abatement shall
commence on the date of discovery of the damage or destruction. Such abatement shall be the sole remedy of Tenant, and except as 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 Building, Property or 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 Building, Property or 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, Building or Property 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 Building or Property or would in
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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. 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 Building and Property 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, the Building’s Share of Project 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, Building, Property or Project. 

20. Events of Default. Each of the following events shall be a substantial 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
at least 5 days before the expiration of the current coverage. 
 (c) Abandonment. Tenant shall abandon the Premises,
provided, however, that Tenant shall be deemed not to have abandoned the Premises if: (i) prior to vacating the Premises Tenant provides Landlord with prior notice and complies with the requirements pertaining to a Surrender Plan as set forth
in Section 28, (ii) prior to or at the time of vacating the Premises, Tenant has made reasonable arrangements for the security of the Premises for the balance of the Term and notified Landlord of such arrangements,
(iii) Tenant continues to maintain in force any permits and approvals as may be required by any Governmental Authority for the Premises, and (iv) Tenant continues during the balance of the Term to satisfy all of its obligations under the
Lease as they come due, including without limitation the obligation to pay Rent. 
 (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 20 days after Tenant receives notice that a 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 

  

			
	

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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) be dissolved or otherwise fail to maintain its legal existence. 
 (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 30 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 30 days to cure, then Tenant
shall not be deemed to be in default if Tenant commences such cure within said 30 day period and thereafter diligently prosecutes the same to completion; provided, however, that such cure shall be completed no later than 60 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. Nothing herein shall be construed to create or impose a duty on Landlord to mitigate any damages resulting from
Tenant’s Default hereunder. 
 (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
of 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
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. 

  

			
	

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 (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 rights 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 free of any rights of Tenant, 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 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
reasonable 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. 

  

			
	

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 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. 
 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 based upon Landlord’s reasonable estimate of Tenant’s Share of Operating
Expenses and other Additional Rent for each 12-month period in what would have been the remainder of the Term of the Lease and any part thereof at the end of such remainder of the Term, but in no event less
than the amounts therefor payable for the twelve (12) calendar months (or if less than twelve (12) calendar months have elapsed since the date hereof, the partial year) immediately preceding the date of Landlord’s Lump Sum Election.
Amounts of Tenant’s Share of Operating Expenses and any other Additional Rent for any partial year at the beginning of the Term or at the end of what would have been the remainder of the Term shall be prorated. 

  

			
	

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 (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 Tenant 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 Tenant was in default, Tenant shall pay to Landlord 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 an 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 discharged, released or bonded over to Landlord’s satisfaction by Tenant within the time period required pursuant to Section 15 of this Lease, and
(b) in any other case if such default continues after any applicable notice and cure period provided in Section 20. 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 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 30 days after demand. 

(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(d). 
 (xii) In the event
that Tenant is in 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 Default, as provided in this Section 21(c). Such costs shall include reasonable 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, reasonable 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, by any third party against Tenant or by or against any person holding any interest under or using the Premises by license of or agreement with Tenant. 

  

			
	

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 (xiii) 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 Landlord of any provision of this Lease shall be deemed to have been made unless expressly so made in writing by Landlord expressly waiving such provision.
Landlord 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 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 or undergo a public offering 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. 

(i) Permitted Transfers Generally. If Tenant desires to assign, sublease, hypothecate or otherwise transfer this Lease
or sublet the Premises, 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, (ii) refuse such consent, in its reasonable discretion, or (iii) with respect to any assignment or any sublease that would result in more than 50% rentable square feet of the
Premises being subleased for substantially the remaining balance of the Term, terminate this Lease with respect to the space described in the Assignment Notice as of the Assignment Date (an “Assignment Termination”). 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 

  

			
	

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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 Three Thousand Dollars ($3,000) in connection with its consideration of any Assignment Notice and/or its
preparation or review of any consent documents; provided that it shall be reasonable for Landlord to withhold its consent, among other reasons, in any of the following instances: (A) the business or financial reputation of the proposed assignee
or sublessee, or the business or financial reputation of any of the respective principals or officers thereof, is objectionable in Landlord’s reasonable judgment, (B) the proposed assignee or subtenant is engaged in areas of scientific
research or other business concerns that are controversial such that they may (i) attract or cause negative publicity for or about the Building or the Project, (ii) negatively affect the reputation of the Building, the Project or Landlord,
(iii) attract protestors to the Building or the Project, or (iv) lessen the attractiveness of the Building or the Project to any tenants or prospective tenants, purchasers or lenders, (C) the proposed assignee or sublessee is at that
time an occupant of the Project or negotiating with Landlord or an affiliate thereof for the lease of other space in the Project, (D) the proposed assignee or sublessee lacks the creditworthiness to support the financial obligations it would
incur under the proposed assignment or sublease, (E) the proposed assignee or sublessee is a governmental agency, (F) in Landlord’s reasonable judgment, the use of the Premises by the proposed assignee or sublessee would entail any
alterations that would lessen the value of the leasehold improvements in the Premises, or would require increased services by Landlord, (G) Landlord has experienced previous defaults by or is in litigation with the proposed assignee or
sublessee (H) the proposed assignment or sublease will create a vacancy elsewhere in the Project, or (I) the assignment or sublease is prohibited by Landlord’s lender. In any event, 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) Affiliate
Transactions. Notwithstanding the foregoing, Landlord’s consent to a sublease to any entity controlling, controlled by or under common control with Tenant (each, an “Affiliate” and collectively
“Affiliates”) shall not be required, provided that Landlord shall have the right to approve the form of any such sublease, such approval not to 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 an Affiliate or 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: (A) in the case of an assignment to a successor in interest, such merger,
consolidation, reorganization or purchase, as the case may be, is for a good business purpose and not principally for the purpose of transferring the Lease; and (B) in all events the net worth (as determined in accordance with generally
accepted accounting principles (“GAAP”)) of the Affiliate assignee or successor in interest to Tenant is not less than the net worth (as determined in accordance with GAAP) of Tenant as of the date of Tenant’s most current
quarterly or annual financial statements as delivered under Section 40(c) or filed with the Securities and Exchange Commission; and (C) such Affiliate assignee or successor-in-interest to Tenant shall agree in writing to assume all of the terms, covenants and conditions of this Lease (any assignment of this Lease or sublease to an Affiliate or a successor-in-interest in accordance with this paragraph is referred to herein as a “Permitted Assignment”). 

(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 

  

			
	

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 (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 (such excess, the “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. 

(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. 

  

			
	

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 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 reasonably 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, 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 shall perform all of the covenants and agreements herein required to be performed by Tenant,
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 and delivered to Tenant in writing covering use of the Premises and the Project or portion thereof of which the Premises are a part. 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. 

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, Property, Building or 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. 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, ground leases or other
superior leases 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. 

  

			
	

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 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 $5, 000. 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 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 Building, restrooms or all or any portion of the
Premises, Building or Project 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 cost of replacing such lost access card or key or the 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. 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. 

  

			
	

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 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, Building, Property or 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, Building, Property or Project or any
adjacent property or if contamination of the Premises, Building, Property or 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 or breach by Tenant of its obligations under this Section 30. 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, Building, Property, Project or any adjacent property caused or permitted by Tenant or any Tenant Party results in any
contamination of the Premises, Building, Property, 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,
Building, Property, Project or any adjacent property to the condition 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, Building, Property or the Project. Notwithstanding anything to the contrary contained in Section 28 or
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 to
Landlord’s reasonable satisfaction 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 to Landlord’s reasonable satisfaction
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 (other than Hazardous Material contained in products customarily used by tenants in de minimis quantities for ordinary cleaning and office purposes) 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”). 

  

			
	

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Upon Landlord’s request, or any time that Tenant is required to deliver a Hazardous Materials List to any Governmental Authority (e.g., the fire department) in connection with Tenant’s
use or occupancy of the Premises, Tenant shall deliver to Landlord a copy of such Hazardous Materials List. 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 Building or Property (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 Building or Property 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, Building, Property or 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 test procedures 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, Building, Property and Project to determine if contamination has occurred as a result of Tenant’s use of the Premises. In connection with such testing, 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 for which Tenant is responsible under
this Lease 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) Underground Tanks. Tenant shall have no right to use or install any underground storage tanks at the Project. 

  

			
	

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 (f) 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. 

(g) 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, Building, Property
or 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. 

(h) Asbestos. 

(i) Notification of Asbestos. Landlord hereby notifies Tenant of the presence of asbestos-containing materials
(“ACMs”) and/or presumed asbestos-containing materials (“PACMs”) within or about the Premises in the locations identified in Exhibit G. 

(ii) Tenant Acknowledgement. Tenant hereby acknowledges receipt of the notification in paragraph (i) of this
Section 30(h) and understand that the purpose of such notification is to make Tenant, and any agents, employees, and contractors of Tenant, aware of the presence of ACMs and/or PACMs within or about the Building in order to
avoid or minimize any damage to or disturbance of such ACMs and/or PACMs. 
         /s/
IG     Tenant’s Initials 
 (iii) Acknowledgement from Contractors/Employees. Tenant
shall give Landlord at least 14 days’ prior written notice before conducting, authorizing or permitting any of the activities listed below within or about the Premises, and before soliciting bids from any person to perform such services. Such
notice shall identify or describe the proposed scope, location, date and time of such activities and the name, address and telephone number of each person who may be conducting such activities. Thereafter, Tenant shall grant Landlord reasonable
access to the Premises to determine whether any ACMs or PACMs will be disturbed in connection with such activities. Tenant shall not solicit bids from any person for the performance of such activities without Landlord’s prior written approval.
Upon Landlord’s request, Tenant shall deliver to Landlord a copy of a signed acknowledgement from any contractor, agent, or employee of Tenant acknowledging receipt of information describing the presence of ACMs and/or PACMs within or about the
Premises in the locations identified in Exhibit G prior to the commencement of such activities. Nothing in this Section 30(h) shall be deemed to expand Tenant’s rights under the Lease or otherwise to conduct,
authorize or permit any such activities. 

  

			
	

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 (A) Removal of thermal system insulation (“TSI”) and
surfacing ACMs and PACMs (i.e., sprayed-on or troweled-on material, e.g., textured ceiling paint or fireproofing material); 

(B) Removal of ACMs or PACMs that are not TSI or surfacing ACMs or PACMs; or 

(C) Repair and maintenance of operations that are likely to disturb ACMs or PACMs. 

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 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, or portion thereof of which the Premises are a part, 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 and the assumption of its interests by the transferee, 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. 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 on the Premises, Building or Property stating the Premises or Building are available to let or
that the Building, Property or Project is available for sale. Landlord shall use reasonable efforts to minimize interference with Tenant’s business operations at the Premises in connection with its entry into the Premises under this
Section 32. Landlord may grant easements, make public dedications, designate Common Areas and create restrictions on or about the Premises, Building and Property, 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. 
 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 

  

			
	

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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, Building, Property and/or 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, 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, 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 Newmark Knight Frank. Landlord and Tenant each hereby agree to indemnify and
hold the other harmless from and against any claims by any Broker, other than the broker, if any named in this Section 35, 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 Newmark Knight Frank arising out of the execution of this Lease in accordance with the terms of a separate written agreement
between Newmark Knight Frank and Landlord. 
 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 PROPERTY OR ANY PROCEEDS FROM SALE OR CONDEMNATION THEREOF AND ANY INSURANCE PROCEEDS PAYABLE IN RESPECT OF LANDLORD’S INTEREST IN THE PROPERTY OR IN CONNECTION WITH ANY SUCH LOSS; AND (C) IN NO EVENT SHALL
ANY PERSONAL LIABILITY BE ASSERTED AGAINST 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. 
 NOTWITHSTANDING ANYTHING TO THE CONTRARY CONTAINED IN
THIS LEASE, IN NO EVENT SHALL PERSONAL LIABILITY FOR TENANT’S OBLIGATIONS UNDER THIS LEASE BE ASSERTED AGAINST ANY OF TENANT’S OFFICERS, DIRECTORS, EMPLOYEES OR AGENTS. 

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. 

  

			
	

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 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 Building,
(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, Building, Property or 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. Standard signage on the floor on which the Premises is located and the directory tablet shall be inscribed, painted or affixed
for Tenant by Landlord at Landlord’s cost, and shall be of a size, color and type 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. 
 39. 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 the right (the “Extension Right”) to extend the term of this Lease for one additional 2 year term (the “Extension Term”) on the same terms and conditions as this Lease (other than Base Rent and the Work Letter)
by giving Landlord written notice of its election to exercise the Extension Right at least 12 months prior to the expiration of the Base Term of the Lease. 

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 the Extension Term by a percentage as determined by Landlord and agreed to by Tenant at the time the Market Rate is determined. As used herein, “Market Rate” shall mean the
then market rental rate for comparably improved laboratory space in the East Cambridge submarket of Boston as determined by Landlord and agreed to by Tenant, or determined by arbitration as provided below. In addition, Landlord may impose a market
rent for the parking rights provided hereunder. 
 If, on or before the date which is 210 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 39(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 39(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

  

			
	

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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. 
 (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 life sciences space in the greater Cambridge, Massachusetts 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 office and life sciences space in the greater Cambridge, Massachusetts metropolitan area; (ii) devoting substantially all of their time to professional appraisal or brokerage work, as
applicable, at the time of appointment; and (iii) shall be in all respects impartial and disinterested. 
 (c) Rights Personal.
The Extension 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. 
 (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 (beyond any applicable notice and cure periods) 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. 

(iii) except for a Permitted Assignment, if Tenant is not in occupancy of at least 75% of the entire Premises demised hereunder
both at the time of the exercise of the Extension Right and at the time of the commencement date of the Extension Term. 
 (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. 

  

			
	

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 (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. 

40. 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. Upon written request from Landlord, Tenant shall furnish Landlord with true and complete copies of (i) Tenant’s most recent audited annual financial statements within 120 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 75 days of the end of each of Tenant’s first three fiscal quarters of each of Tenant’s fiscal years during
the Term. If the stock of Tenant is publicly traded on a recognized national exchange, then Tenant’s filing of quarterly and annual financial statements with the Securities and Exchange Commission shall be deemed to satisfy Tenant’s
obligations to deliver financial statements under this Section. 
 (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) Entire Agreement; Amendment. This Lease constitutes the entire agreement between Landlord and Tenant pertaining to the lease
of the Premises and supersedes all other agreements, whether oral or written, pertaining to the lease of the Premises, and no other agreements with respect thereto shall be effective. Any amendments or modifications of this Lease shall be in writing
and signed by both Landlord and Tenant, and any other attempted amendment or modification of this Lease shall be void. 
 (h) 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 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 

  

			
	

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 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. 
 (i) Choice of Law.
Construction and interpretation of this Lease shall be governed by the internal laws of the Commonwealth of Massachusetts, excluding any principles of conflicts of laws. 

(j) Time. Time is of the essence as to the performance of Tenant’s obligations under this Lease. 

(k) 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 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. 

(l) 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. 

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

			
	TENANT:
	
	 SOLID BIOSCIENCES, LLC,
 a
Delaware limited liability company

		
	By:	 	/s/ Ilan Ganot
	Print Name:	 	 Ilan Ganot
	Title:	 	CEO

  

									
	LANDLORD:
	
	 ARE-MA REGION NO. 59, 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/ Jackie Clem
		 		 	Print Name:	 	Jackie Clem
		 		 	Title:	 	 Senior Vice President
 RE Legal
Affairs

  

			
	

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		 	1400 One Kendall Square/Solid Biosciences – Page 1

  

 EXHIBIT A TO LEASE  

DESCRIPTION OF PREMISES 
  

 

  

			
	

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 EXHIBIT B TO LEASE  

DESCRIPTION OF PROPERTY 
 Real
property in the County of Middlesex, Commonwealth of Massachusetts, described as follows:  
 Buildings 100, 200, 300, 400 and 500: 

Four registered parcels of land located in the City of Cambridge, Middlesex County, Massachusetts, bounded and described as follows: 

Lot 35 - L.C. Plan 10378G 
 Commencing at the intersection
of the northeasterly line of Hampshire Street with the southeasterly line of Cardinal Medeiros Avenue; 
 Thence running N 36°06’35” E along
said southeasterly line of Cardinal Medeiros Avenue, a distance of 262.69 feet, to a point; 
 Thence running S 53°46’58” E, by land now or
formerly of Trustees of Old Kendall Realty Trust, a distance of 322.66 feet, to a point; 
 Thence running S 36°16’40” W, by Lot 42 shown on
Land Court Plan 10378J, a distance of 48.01 feet, to a point; 
 Thence running by Lot 36, shown on Land Court Plan 10378G, on the following four
(4) courses: 
 N 53°40’39” W, a distance of 65.11 feet, to a point; 

S 36°04’50” W, a distance of 126.58 feet, to a point; 

S 53°32’32” E, a distance of 42.30 feet, to a point; and 

S 28°34’58” E, a distance of 12.62 feet, to a point at land now or formerly of Trustees of Kendall Three Realty Trust; 

Thence running S 60°21’50” W, in part by land of said Trustees and in part by land now or formerly of Charles Stark Draper Laboratory, Inc. a
distance of 205.87 feet, to a point on the aforesaid northeasterly line of Hampshire Street; 
 Thence running N 28°54’10” W, along said
northeasterly line of Hampshire Street, a distance of 250.01 feet, to the Point of Beginning. 
 Together with the benefit of easement rights set forth in
an Easement from The Charles Stark Draper Laboratory, Inc. to Cambridge Athenaeum LLC, dated April 16, 2000 and filed as Document No. 1137082. 

Lot 36-L.C. Plan 10378G 

Commencing at a point on the easterly line of the above described parcel, said point being S 36°16’40” W and a distance of 48.01 feet from the
northeast corner of the above described parcel; 
 Thence running S 36°16’40” W, by land of the Trustees of Kendall Three Realty Trust, a
distance of 107.52 feet; to a point; 

  

			
	

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 Thence running S 60°21’50” W, by land of said Trustees, a distance of 26.84 feet, to a point;

 Thence running by Lot 35, shown on Land Court Plan 10378G, on the following four (4) courses: 

N 28°34’58” W, a distance of 12.62 feet, to a point; 

N 53°32’32” W, a distance of 42.30 feet, to a point; 

N 36°04’50” E, a distance 126.58 feet, to a point; and 

S 53°40’39” E, a distance of 65.11 feet, to the Point of Beginning. 

Lot 42 - Land Court Plan 10378J 
 Commencing at the
northeast corner of Lot 35, hereinbefore described; 
 Thence running by land, now or formerly of Trustees of Kendall Three Realty Trust, on the following
three (3) courses: 
 S 53°46’58” E, a distance of 1.97 feet, to a point; 

S 36°25’25” W, a distance of 48.02 feet, to a point; and 

N 53°40’39” W, a distance of 1.85 feet, to a point; 

Thence running N 36°16’40” E, by Lot 35, a distance of 48.01 feet, to the Point of Beginning.  

Lot 43 - Land Court Plan 10378J 
 A certain parcel of land
situate in Cambridge in the County of Middlesex, Commonwealth of Massachusetts: 
 Northeasterly by lot 39 as shown on plan hereinafter mentioned, thirteen
and 05/100 feet; 
 Southeasterly forty-eight and 04/100 feet; and 

Southwesterly thirteen and 28/100 feet by lot 41 on said plan; and 

Northwesterly by lot 42 on said plan, forty-eight and 02/100 feet. 

Said parcel is shown as Lot 43 on Land Court Plan 10378J. 
 All
of said boundaries are determined by the Court to be located as shown on a subdivision plan, as approved by the Court, filed in the Land Registration Office, a copy of which is filed in the Registry of Deeds in Registration Book 1050, Page 90, with
Certificate 184040. 
 Together with the rights and easements set forth in that certain Grant of Easement from Charles Stark Draper Laboratory, Inc. dated
August 31, 1983, filed with the Middlesex County Registry District of the Land Court (the “District”) as Document No. 657256. 

Together with the rights and easements set forth in that certain Easements Agreement dated December 17, 1984 and filed as Document No. 673502, as
affected by Amendment to Easements Agreement, dated April 7, 2006 and filed as Document No. 1416496. 

  

			
	

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 Together with the rights and easements set forth in a Grant of Easement dated August 30,1983 and filed
as Document No. 654750. 
 Together with the rights and easements set forth in a Grant of Easement from the City of Cambridge, dated January 29,
2009 and recorded in Book 52168, Page 362. 
 The foregoing parcels collectively are also described as follows: 

Those certain parcels of registered land located in Cambridge, Middlesex County, Massachusetts, shown as Lots 35 and 36 on Land Court Plan 10378G and Lots 42
and 43 shown on Land Court Plan 10378J, bounded and described as follows: 
 Beginning at the point on the northeasterly sideline of Hampshire Street 250.01
feet distance southeasterly from intersection of easterly sideline of Cardinal Medeiros Avenue and northeasterly side line of Hampshire Street thence bounded: 

Southwesterly by the northeasterly line of Hampshire Street, two hundred fifty and 01/100 (250.01) feet; 

Northwesterly by the southeasterly line of Cardinal Medeiros Avenue, two hundred sixty two and 69/100 (262.69) feet; 

Northeasterly by land now or formerly of Cambridge Athenaeum LLC, three hundred thirty seven and 68/100 (337.68) feet; 

Southeasterly by land now or formerly of Amgen Cambridge Real Estate Holdings Inc., forty-eight and 04/100 (48.04) feet; 

Southwesterly by land of said Amgen Cambridge Real Estate Holdings Inc., fifteen and 13/100 (15.13) feet; 

Southeasterly by said land now or formerly of Amgen Cambridge Real Estate Holdings Inc., one hundred seven and 52/100 (107.52) feet; and 

Southeasterly by land now or formerly of Amgen Cambridge Real Estate Holdings Inc. and Charles Stark Draper Laboratory, Inc., two hundred thirty two and
71/100 (232.71) feet. 
 Buildings 600, 650 and 700: 

Lot 39 - Land Court Plan 10378H 
 That certain parcel of
land situated in the City of Cambridge, Middlesex County, Massachusetts, bounded and described as follows: 
 Commencing at a point on the Easterly side of
Cardinal Medeiros Avenue, said point being sixty feet from the intersection of said Easterly side of Cardinal Medeiros Avenue and the Southerly line of Binney Street; 

Northerly, by Lot 40 shown in Land Court Plan 103781, two hundred thirty-eight and sixty-three hundredths (238.63) feet,
eighty-two and forty-one hundredths (82.41) feet and seventeen and four hundredths (17.04) feet; 

Easterly, by Lots 40 and 41 shown on Land Court Plan 10378l, one hundred ninety-six and eighty-four hundredths
(196.84) feet, 

  

			
	

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 Southerly by Lots 43 and 42 shown on Land Court Plan 10378J and Lot 35 shown on Land Court Plan 10378G three
hundred thirty-seven and sixty-eight hundredths (337.68) feet; 
 Westerly, on aforesaid Cardinal Medeiros Avenue, one hundred ninety-nine and seventy-one hundredths (199.71) feet. 
 The parcel of land described above is shown as Lot 39 on Land Court Plan 10378H.
 
 Lot 40 (Building 1400) 
 The land with the
buildings and improvements thereon, shown as Lot 40 on Land Court Plan 10378l, situated on Binney Street in the City of Cambridge, County of Middlesex, Massachusetts, also shown on a plan entitled “Topographic Plan for Old Binney Realty Trust,
Cardinal Medeiros Avenue, Binney Street; Cambridge, Massachusetts”, dated June 29, 1987, as revised July 10, 1987, April 13, 1988, August 12, 1988, September 6, 1988, and September 26, 1988, prepared by cullinan
Engineering Co., Inc., being bounded and described as follows; 
 NORTHEASTERLY by the southwesterly line of Binney Street, two hundred sixty-six and 80/100 (266.80) feet and two hundred twenty and 44/100 (220.44) feet; 
 EASTERLY by land now or formerly of
Consolidated Rail Corporation, eighty-nine and 24/100 (89.24) feet; 
 SOUTHWESTERLY by Lot 41 on Land Court Plan 103781, twenty seven and 16/100 (27.16)
feet; 
 SOUTHWESTERLY by said Lot 41, thirty-five and 12/100 (35.12) feet and one hundred two and 73/100 (102.73) feet; 

NORTHWESTERLY by Lot 39 on Land Court Plan 10378H, sixty-six and 15/100 (66.15) feet; 

SOUTHWESTERLY by said Lot 39, seventeen and 04/100 (17.04) feet; 

SOUTHWESTERLY by said Lot 39, eighty-two and 41/100 (82.41) feet; 

SOUTHWESTERLY by said Lot 39, two hundred thirty-eight and 63/100 (238.63) feet; 

NORTHWESTERLY by Cardinal Medeiros Avenue (formerly known as Portland Street), sixty and 00/100 (60) feet. 

Together with the rights set forth in Easements Agreement dated December 17, 1984, between Old Cambridge Realty Trust and the Old Kendall Trustees, filed
as Document No. 673502, as affected by Amendment to Easements Agreement, dated April 7, 2006 and filed as Document No. 1416496. 
 Together
with the rights set forth in Parking Access Easement Agreement filed as Document No. 771896, as affected by Release of Parking Rights by Robert A. Jones and George Najarian, Trustees of Old Binney Realty Trust, dated January 11, 1995,
recorded in Book 25122, Page 94 and filed as Document No. 966485, Release of Parking Rights by Robert A. Jones, Managing Trustee of Old Cambridge Realty Trust dated January 11, 1995, recorded in Book 25122, Page 98 and filed as Document
No. 966486; Release of Parking Rights by Robert A. Jones, Managing Trustee of Old Kendall Realty Trust, dated January 11, 1995, recorded in Book 25122, Page 102 and filed as Document No.966487; Release of Parking Rights by State Street
Bank and Trust Company, Trustees of Kendall One Realty Trust dated January 5, 1995, recorded in Book 25122, Page 106 and filed as Document No. 966488, and Release of Parking Rights dated January 10, 1995, recorded in Book 25153, Page
386 and as filed as Document No. 967459. 

  

			
	

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	Work Letter - Tenant Build	 	1400 One Kendall Square/Solid Biosciences – Page 5

  

 Together with the rights set forth in that certain Parking and Access Easement Agreement, by and between DWF
IV One Kendall, LLC and DWF IV One Kendall Garage, LLC, dated as of January 16, 2014 and recorded in Book 63188, Page 559, and filed as Document No. 1663415. 

  

			
	

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	Work Letter – Tenant Build	 	1400 One Kendall Square/Solid Biosciences – Page 1

  

 EXHIBIT C TO LEASE 

WORK LETTER 
 THIS
WORK LETTER (this “Work Letter”) is attached to and incorporated into that certain Lease dated December 22, 2017 (the “Lease”) by and between ARE-MA REGION NO.
59, LLC, a Delaware limited liability company (“Landlord”), and SOLID BIOSCIENCES, LLC, a Delaware limited liability company (“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 Alvaro Amorrortu and Patrick Guinee (either such individual acting alone, “Tenant’s Representative”) as the only persons 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 either 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 Mike Carli (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 “TI 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 shall be named a third party beneficiary of any contract entered into by Tenant with the TI 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 all improvements to the Premises desired by Tenant of a fixed and permanent nature. Other than funding the TI 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. 
 (b) Tenant’s Space
Plans. Tenant shall deliver to Landlord schematic drawings and outline specifications (the “TI Design Drawings”) detailing Tenant’s requirements for the Tenant Improvements within 10 days of the date hereof. Not more
than 10 days thereafter, Landlord shall deliver to Tenant the written objections, questions or comments of Landlord and the TI Architect with regard to the TI Design Drawings. Tenant shall cause the TI Design Drawings to be revised to address such
written comments and shall resubmit said drawings to Landlord for approval within 10 days thereafter. Such process shall continue until Landlord has approved the TI Design Drawings. 

(c) Working Drawings. Not later than 15 business days following the approval of the TI Design Drawings by Landlord, Tenant shall cause
the TI Architect to prepare and deliver to Landlord for review and comment construction plans, specifications and drawings for the Tenant Improvements (“TI Construction Drawings”), 

  

			
	

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	Work Letter – Tenant Build	 	1400 One Kendall Square/Solid Biosciences – Page 2

  

 
which TI Construction Drawings shall be prepared substantially in accordance with the TI Design Drawings. Tenant shall be solely responsible for ensuring that the TI Construction Drawings
reflect Tenant’s requirements for the Tenant Improvements. Landlord shall deliver its written comments on the TI 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 TI Design Drawings. Tenant and the TI 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 TI Construction Drawings is consistent with the TI
Design Drawings, Landlord shall approve the TI Construction Drawings submitted by Tenant. Once approved by Landlord, subject to the provisions of Section 4 below, Tenant shall not materially modify the TI Construction
Drawings except as may be reasonably required in connection with the issuance of the TI 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 TI 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 TI 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 not commence construction of the Tenant Improvements prior to obtaining and delivering to Landlord a building permit (the “TI Permit”) authorizing the construction of the Tenant
Improvements consistent with the TI Construction Drawings approved by Landlord. The cost of obtaining the TI Permit shall be payable from the TI Fund. Landlord shall assist Tenant in obtaining the TI 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 TI 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 TI 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. 
 (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 TI 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 TI 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 

  

			
	

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	Work Letter – Tenant Build	 	1400 One Kendall Square/Solid Biosciences – Page 3

  

 
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 TI 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 TI 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 TI 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 TI Permit
modification or change is required as a result of such Change, Tenant shall promptly provide Landlord with a copy of such TI 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 or delayed. The Budget shall be based upon the TI Construction Drawings
approved by Landlord. If the Budget is greater than the TI 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) TI Allowance. Landlord shall provide to Tenant a tenant improvement allowance
(“TI Allowance”) of $60.00 per rentable square foot of the Premises, or $569,340.00 in the aggregate. Notwithstanding anything to the contrary contained herein, if Tenant surrenders its existing premises at 161 First Street,
Cambridge, Massachusetts, in accordance with the surrender requirements of that certain Lease Agreement dated as of February 29, 2016, between Tenant, as tenant, and ARE-MA Region No. 21, LLC, a
Delaware limited liability company, as landlord (the “161 Lease”), on or before February 15, 2018, and Tenant is not otherwise in Default (as defined in the 161 Lease) under the 161 Lease, then the TI Allowance shall be
increased by $15.00 per rentable square foot of the Premises. 
 The TI 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 TI Allowance not required for the construction of (i) the Tenant Improvements described in the TI Construction Drawings approved
pursuant to Section 2(d) or (ii) any Changes pursuant to Section 4. Tenant shall have no right to any portion of the TI Allowance that is not disbursed before the last day of the month that is
18 months after the Commencement Date. 
 (c) Costs Includable in TI Fund. The TI 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

  

			
	

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	Work Letter – Tenant Build	 	1400 One Kendall Square/Solid Biosciences – Page 4

  

 
construction of the Tenant Improvements, the cost of preparing the TI Design Drawings and the TI Construction Drawings, all costs set forth in the Budget and the cost of Changes (collectively,
“TI Costs”). Notwithstanding anything to the contrary contained herein, the TI 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, Tenant’s voice or data cabling, non-ducted biological safety cabinets and other scientific equipment not incorporated into the Tenant Improvements. 

(d) Excess TI 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 TI Allowance. If at any time and from time-to-time, the remaining TI Costs under the Budget exceed the remaining unexpended TI Allowance
(“Excess TI Costs”), monthly disbursements of the TI Allowance shall be made in the proportion that the remaining TI Allowance bears to the outstanding TI Costs under the Budget, and Tenant shall fund the balance of each monthly
draw. For purposes of any litigation instituted with regard to such amounts, those amounts will be deemed Rent under the Lease. The TI Allowance and Excess TI Costs is herein referred to as the “TI Fund.” Notwithstanding anything to
the contrary set forth in this Section 5(d), Tenant shall be fully and solely liable for TI Costs and the cost of Minor Variations in excess of the TI Allowance. 

(e) Payment for TI Costs. During the course of design and construction of the Tenant Improvements, subject to the terms of
Section 5(d) above, Landlord shall reimburse Tenant for TI 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 TI 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 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) Default. Notwithstanding anything set forth herein or
in the Lease to the contrary, Landlord shall not have any obligation to perform any work hereunder or to fund any portion of the TI Fund during any period Tenant is in Default under the Lease. 

  

			
	

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	Acknowledgment of Commencement Date	 	1400 One Kendall Square/Solid Biosciences – Page 1

  

 EXHIBIT D TO LEASE 

ACKNOWLEDGMENT OF COMMENCEMENT DATE 

This ACKNOWLEDGMENT OF COMMENCEMENT DATE is made as of this
             day of                     ,
             between ARE-MA REGION NO. 59, LLC, a Delaware limited liability company (“Landlord”), and
SOLID BIOSCIENCES, LLC, a Delaware limited liability company (“Tenant”), and is attached to and made a part of the Lease dated as of
November            , 2017 (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 this
Acknowledgment of Commencement Date and the Lease, 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:
	
	SOLID BIOSCIENCES, LLC,
	a Delaware limited liability company

 
			
		
	By: 	 	 

 
			
	Print Name:	 	 

 
			
	Title:	 	 

  

					
	LANDLORD:
	
	ARE-MA REGION NO. 59, 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: 	 	 

 
							
		 		 	Print Name:	 	 

 
							
		 		 	Title:	 	 

  

			
	

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	Rules and Regulations	 	1400 One Kendall Square/Solid Biosciences – Page 1

  

 EXHIBIT E TO LEASE  

RULES AND REGULATIONS 

1. The sidewalk, entries, and driveways of the Building, Property or 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 Building. 

3. Except for animals assisting the disabled, no animals shall be allowed in the offices, halls, or corridors in the Building, Property or
Project. 
 4. Tenant shall not disturb the occupants of the Building, Property or 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 Building, Property or Project. 
 7. Parking any type of recreational vehicles is specifically prohibited on or about the Building,
Property or 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 maintain the Premises free
from rodents, insects and other pests. 
 9. Landlord reserves the right to exclude or expel from the Building, Property or 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 Building, Property or 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. 

  

			
	

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	Rules and Regulations	 	1400 One Kendall Square/Solid Biosciences – 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, Building, Property or 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 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 Building, Property and 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. 

  

			
	

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	Tenant’s Personal Property	 	1400 One Kendall Square/Solid Biosciences – Page 1

  

 EXHIBIT F TO LEASE  

TENANT’S PERSONAL PROPERTY 

None. 

  

			
	

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		 	1400 One Kendall Square/Solid Biosciences – Page 1

  

 EXHIBIT G TO LEASE 

NOTIFICATION OF THE PRESENCE OF ASBESTOS CONTAINING MATERIALS 

This notification provides certain information about asbestos within or about the Premises at Building 1400, One Kendall Square, Boston, Massachusetts
(“Building”). 
 Historically, asbestos was commonly used in building products used in the construction of buildings across the country.
Asbestos-containing building products were used because they are fire-resistant and provide good noise and temperature insulation. Because of their prevalence, asbestos-containing materials, or ACMs, are still sometimes found in buildings today.

 Building 1400 was constructed in the early 1900s. No specific asbestos sampling/analysis data has been provided. Based on the 2002 visual survey, the
following materials were observed in Building 1400 that might contain asbestos, referred to as presumed asbestos-containing materials or PACMS: 

Building 1400 
  

			
	 Material Description
	  	 Material Location

		
	Drywall/joint compound	  	 All Floors: throughout walls; portions of east and center elevator lobby ceilings

 
 Fourth Floor: locker room ceilings

		
	12” gray floor tile and mastic	  	Basement: west hallway by stairs
		
	White with gray vinyl sheet flooring	  	Basement: Microbia glass wash room
		
	12” white/blue/pink floor tile and mastic	  	 First Floor: Suntory Pharmaceutical, northwest laboratory, kitchen, and east side rooms

 
 Second Floor: Microbia, west side laboratory (assumed throughout)

		
	White vinyl sheet flooring	  	First Floor: Suntory Pharmaceutical, south side laboratories
		
	12” beige floor tile and mastic	  	First Floor: loading dock and service elevator hallway
		
	12” light gray floor tile and mastic	  	First Floor: Incert Software, kitchen
		
	12” white with gray floor tile and mastic	  	 Second Floor: Microbia, east side hallway by stairs
  

Third Floor: Microbia, southwest hallway

		
	12” light gray floor tile and mastic	  	Third Floor: Microbia, center hallway and hallways by center and east stairs
		
	12” white with black speck floor tile and mastic	  	Fourth Floor: Microbia, west end laboratory (assumed throughout)
		
	12” gray and white floor tile and mastic	  	Fourth Floor: Microbia, southwest hallway and east side lunch room
		
	Gray rubberized flooring	  	Fourth and Fifth Floors: Microbia, center stairwell
		
	12” dark gray floor tile and mastic	  	Fifth Floor: Microbia, east side hallway and elevator lobby
		
	12” white and gray floor tile and mastic	  	Fifth Floor: Microbia, east side hallways; west side laboratories (assumed throughout)
		
	12” gray floor tile and mastic	  	Fifth Floor: Microbia, center stairwell landing
		
	2’ x 4’ ceiling tile	  	First Floor: Suntory Pharmaceutical, laboratory (assumed throughout)
		
	2’ x 2’ ceiling tile (curves pattern)	  	First Floor: Suntory Pharmaceutical, north offices

  

			
	

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		 	1400 One Kendall Square/Solid Biosciences – Page 2

  

			
	 Material Description
	  	 Material Location

		
	2’ x 2’ ceiling tile	  	First Floor: Incert Software, center office areas
		
	2’ x 2’ ceiling tile	  	 First Floor: Genzyme, office areas (assumed throughout)
  

Second Floor: Genzyme, east side office areas; Microbia office areas (201)
  

Third Floor: Genzyme, southwest hallway, center and east side offices (302-304)

 
 Fourth Floor: Genzyme, offices and laboratories (assumed throughout)

 
 Fifth Floor: Genzyme, center and east side offices (assumed throughout)

		
	2’ x 4’ ceiling tile	  	 Second Floor: Microbia, west side laboratory (assumed throughout); Genzyme, center office areas (203)

 
 Third Floor: Genzyme, west side laboratory (assumed throughout)

 
 Fifth Floor: Genzyme, west side laboratory (assumed throughout)

		
	Fireproofing	  	All Floors: beams and columns, with some overspray on decking
		
	Stucco	  	Exterior overhang and east side walk area and perimeter of windows

 Because ACMs and PACMs may be present within or about the Building, we have hired an independent environmental consulting firm
to prepare an operations and maintenance program (“O&M Program”). The O&M Program is designed to minimize the potential of any harmful asbestos exposure to any person within or about the Building. The O&M Program
includes a description of work methods to be taken in order to maintain any ACMs or PACMs within or about the Building in good condition and to prevent any significant disturbance of such ACMs or PACMs. Appropriate personnel receive regular
periodic training on how to properly administer the O&M Program. 
 The O&M Program describes the risks associated with asbestos exposure and how to
prevent such exposure through appropriate work practices. ACMs and PACMs generally are not thought to be a threat to human health unless asbestos fibers are released into the air and inhaled. This does not typically occur unless (1) the ACMs
are in a deteriorating condition, or (2) the ACMs have been significantly disturbed (such as through abrasive cleaning, or maintenance or renovation activities). If inhaled, asbestos fibers can accumulate in the lungs and, as exposure
increases, the risk of disease (such as asbestosis or cancer) increases. However, measures to minimize exposure, and consequently minimize the accumulation of asbestos fibers, reduce the risks of adverse health effects. 

The O&M Program describes a number of activities that should be avoided in order to prevent a release of asbestos fibers. In particular, you should be
aware that some of the activities which may present a health risk include moving, drilling, boring, or otherwise disturbing ACMs. Consequently, such activities should not be attempted by any person not qualified to handle ACMs. 

The O&M Program is available for review during regular business hours at Landlord’s office located at 400 Technology Square, Suite 101, Cambridge, MA
02139. 

  

			
	

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