Exhibit 10.1

FOURTH AMENDMENT TO LEASE
THIS FOURTH AMENDMENT TO LEASE (this "Fourth Amendment") is made as of
November 30, 2013 (the “Effective Date”), by and between ARE-SAN FRANCISCO NO.
33, LLC, a Delaware limited liability company ("Landlord"), and PROTHENA
BIOSCIENCES, INC., a Delaware corporation ("Tenant").
RECITALS
A.    Landlord and Tenant are now parties to that certain Lease Agreement dated
as of March 18, 2010, as amended by that certain Letter Agreement dated as of
March 18, 2010, as further amended by that certain First Amendment to Lease
dated as of November 18, 2011, as further amended by that certain Second
Amendment to Lease dated June 1, 2012, and as further amended by that certain
Third Amendment to Lease dated as of October 3, 2012 (as amended, the "Lease").
Pursuant to the Lease, Tenant leases certain premises consisting of
approximately 36,441 rentable square feet (the “Existing Premises”) in a
building located at 650 Gateway Boulevard, South San Francisco, California
(“Building”). The Existing Premises are comprised of (i) that certain portion of
the Building containing approximately 26,299 rentable square feet (the “Original
Premises,” as shown on Exhibit A to the Lease), (ii) that certain portion of the
Building containing approximately 1,251 rentable square feet (the “Additional
Premises,” as shown on Exhibit A to the Lease), and (iii) that certain portion
of the Building containing approximately 8,891 rentable square feet (the “Second
Expansion Premises,” as shown on Exhibit A to the Lease). Capitalized terms used
herein without definition shall have the meanings defined for such terms in the
Lease.
B.    Tenant desires to expand the Existing Premises to include that certain
portion of the Building consisting of approximately 13,959 rentable square feet,
as shown on Exhibit A attached hereto (‘Third Expansion Premises”).
C.     Landlord and Tenant desire, subject to the terms and conditions set forth
below, to amend the Lease to, among other things, expand the Existing Premises
by adding the Third Expansion Premises.
NOW, THEREFORE, in consideration of the foregoing Recitals, which are
incorporated herein by this reference, the mutual promises and conditions
contained herein, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, Landlord and Tenant hereby agree
as follows:
1.
Third Expansion Premises. In addition to the Existing Premises, commencing on
the Third Expansion Premises Commencement Date (as defined below), Landlord
leases to Tenant, and Tenant leases from Landlord, the Third Expansion Premises.
From and after the Third Expansion Premises Commencement Date, the Existing
Premises and the Third Expansion Premises shall be collectively referred to as
the “Premises”.

2.
Delivery. The "Third Expansion Premises Commencement Date" shall be the date
that is 1 business day after the mutual execution and delivery of this Fourth
Amendment by the parties. The “Third Expansion Premises Rent Commencement Date”
shall be April 1, 2015.

Landlord shall deliver the Third Expansion Premises to Tenant on the Third
Expansion Premises Commencement Date. Following the Third Expansion Premises
Commencement Date, Tenant shall have the right to construct Tenant Improvements
(as defined in the Third Expansion Premises Work Letter attached to this Fourth
Amendment as Exhibit B (“Third EP Work Letter”)) pursuant to the terms of the
Third EP Work Letter.

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Except as set forth in the Lease (including without limitation, Section 13 of
the Lease), as modified by this Fourth Amendment and the Third EP Work Letter:
(i) Tenant shall accept the Third Expansion Premises in their condition as of
the Third Expansion Premises Commencement Date, subject to all applicable Legal
Requirements; (ii) Landlord shall not have any obligation to Tenant for any
existing defects in the Third Expansion Premises as of the Third Expansion
Premises Commencement Date; and (iii) Tenant’s taking possession of the Third
Expansion Premises shall be conclusive evidence that Tenant accepts the Third
Expansion Premises in their condition at the time possession was taken.
Without limiting Landlord’s repair obligations under Section 13 of the Lease
with respect to the entire Premises, for the period of 30 consecutive days after
the earlier of (i) the date that Tenant (or any subtenant) occupies all or any
portion of the Third Expansion Premises, or (ii) the Third Expansion Premises
Rent 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 Systems serving the Third Expansion
Premises, if the same were not in good working order as of the Third Expansion
Premises Commencement Date.
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 Third Expansion Premises, and/or the suitability of the Third
Expansion Premises for the conduct of Tenant’s business, and Tenant waives any
implied warranty that the Third Expansion Premises are suitable for the
Permitted Use.
3.
Definition of Premises. Commencing on the Third Expansion Premises Commencement
Date, the defined term "Premises" on page 1 of the Lease is deleted in its
entirety and replaced with the following:

"Premises: That portion of the Building containing approximately 50,400 rentable
square feet, consisting of (i) a portion of the Building containing
approximately 26,299 rentable square feet (the “Original Premises”), (ii) a
portion of the Building containing approximately 1,251 rentable square feet (the
“Additional Premises”), (iii) a portion of the Building containing approximately
8,891 rentable square feet (“Second Expansion Premises”), and (iv) a portion of
the Building containing approximately 13,959 rentable square feet, all as
determined by Landlord (“Third Expansion Premises”), as shown on Exhibit A.”
As of the Third Expansion Premises Commencement Date, Exhibit A to the Lease
shall be amended to include the Third Expansion Premises as shown on Exhibit A
attached to this Fourth Amendment.
4.
Base Term. Commencing on the Third Expansion Premises Commencement Date, the
defined term “Base Term” on page 1 of the Lease is deleted in its entirety and
replaced with the following:

“Base Term: A term beginning (i) with respect to the Original Premises, on the
Commencement Date, (ii) with respect to the Additional Premises, on the
Expansion Premises Commencement Date, (iii) with respect to the Second Expansion
Premises on the Second Expansion Premises Commencement Date, and (iv) with
respect to the Third Expansion Premises, on the Third Expansion Premises
Commencement Date, and ending with respect to the entire Premises on
November 30, 2020.”
5.
Base Rent.

a.Existing Premises. Tenant shall continue to pay Base Rent for the Existing
Premises as provided for in the Lease through the expiration of the Base Term of
the Lease.

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b.Third Expansion Premises. Commencing on the Third Expansion Premises Rent
Commencement Date, Tenant shall commence paying Base Rent for the Third
Expansion Premises at the same rate per rentable square foot that Tenant is
paying for the Existing Premises, as increased pursuant to the schedule set
forth on pages 1 and 2 of the Lease.
Notwithstanding anything to the contrary contained in this Fourth Amendment or
in the Lease, if Tenant enters into one or more subleases with respect to all or
any portion of the Third Expansion Premises prior to the Third Expansion
Premises Rent Commencement Date, Tenant shall be entitled to retain all base
rent payable by the sublessee(s) subject to the sublease(s) through the day that
is immediately before the Third Expansion Premises Rent Commencement Date.
Commencing on the Third Expansion Premises Rent Commencement Date, Tenant shall
be required to pay Landlord any Excess Rents to which Landlord is entitled
pursuant to Section 22(d) of the Lease in connection with any such sublease(s).
6.
Rentable Area of the Premises. Commencing on the Third Expansion Premises
Commencement Date, the defined term "Rentable Area of the Premises" on page 2 of
the Lease is deleted in its entirety and replaced with the following:

"Rentable Area of the Premises: 50,400 sq. ft."
7.
Tenant’s Share. Commencing on the Third Expansion Premises Commencement Date,
the defined terms "Tenant’s Share of Operating Expenses of Building" and
“Tenant’s Share of Operating Expenses of Project” on page 2 of the Lease are
deleted in their entirety and replaced with the following:

"Tenant’s Share of Operating Expenses of Building: 100%
Tenant’s Share of Operating Expenses of Project: 33.39%”
Notwithstanding anything to the contrary contained herein, Tenant shall not be
required to pay Operating Expenses (other than Utilities, which Tenant shall be
required to pay commencing on the Third Expansion Premises Commencement Date)
with respect to the Third Expansion Premises for the period commencing on the
Third Expansion Premises Commencement Date through the Third Expansion Premises
Rent Commencement Date. Tenant shall commence paying Operating Expenses with
respect to the entire Premises on the Third Expansion Premises Rent Commencement
Date.
Notwithstanding anything to the contrary contained herein, if Tenant enters into
one or more subleases with respect to all or any portion of the Third Expansion
Premises prior to the Third Expansion Premises Rent Commencement Date, Tenant
shall be required to pay Operating Expenses with respect to that portion of the
Third Expansion Premises subject to the sublease(s) as of the commencement date
of such sublease; provided, however, that if Tenant provides free rent to any
sublessee(s), Tenant shall not be required to pay Operating Expenses as required
under this paragraph for the first 5 months of such free rent period.
8.
Food Trucks. Tenant may engage mobile food service vendors (“Food Vendors”) to
provide food services for the Premises provided that (i) each Food Vendor shall
be reasonably acceptable to Landlord, (ii) the location within the parking areas
of the Project where the Food Vendors may park (“Food Vendor Area”) and the
hours during which the Food Vendors may be present at the Project shall be
subject to Landlord’s reasonable approval; (iii) Tenant shall deliver
certificates of insurance for each Food Vendor evidencing the maintenance by
such Food Vendor of insurance in form and substance reasonably acceptable to
Landlord; (iv) Tenant shall be responsible, at Tenant’s sole cost, for ensuring
that the Food Vendor Area remains free and debris and trash while and
immediately following any Food Vendor is in the Food Vendor Area; (v) the Food

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Vendors shall not interfere with the use of the Project by any other tenants of
the Project, and (vi) each Food Vendor shall execute a waiver, in a form
reasonably acceptable to Landlord and Tenant, pursuant to which such Food Vendor
waives any claims it may at such time or in the future have against Landlord or
Tenant in connection with such Food Vendor’s activities at the Project. In the
event of any such interference or if any Food Vendor causes any damage to the
Project, Landlord shall have the right to immediately remove a Food Vendor from
the Project or prohibit a Food Vendor from entering the Project. Tenant shall be
fully responsible for the acts of Food Vendors and their invitees at the Project
and under no circumstances shall Landlord have any liability to any Food Vendors
and/or in connection with any of the rights granted to Food Vendors under this
paragraph.
9.
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 the transaction reflected in this Fourth Amendment and that no Broker
brought about this transaction, other than Cassidy Turley and DTZ Americas, as
co-agents, representing the Tenant (collectively, “Tenant’s Broker”) and Cornish
& Carey/NKF representing the Landlord (“Landlord’s Broker”). Except for the
brokerage fees of Tenant’s Broker and Landlord’s Broker, which shall be paid by
Landlord pursuant to a separate written agreement with such Brokers, Landlord
and Tenant each hereby agrees to indemnify and hold the other harmless from and
against any claims by any Broker 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.

10.
Miscellaneous.

a.This Fourth Amendment is the entire agreement between the parties with respect
to the subject matter hereof and supersedes all prior and contemporaneous oral
and written agreements and discussions. This Fourth Amendment may be amended
only by an agreement in writing, signed by the parties hereto.
b.This Fourth Amendment is binding upon and shall inure to the benefit of the
parties hereto, their respective agents, employees, representatives, officers,
directors, divisions, subsidiaries, affiliates, assigns, heirs, successors in
interest and shareholders.
c.This Fourth Amendment may be executed in any number of counterparts, each of
which shall be deemed an original, but all of which when taken together shall
constitute one and the same instrument. The signature page of any counterpart
may be detached therefrom without impairing the legal effect of the signature(s)
thereon provided such signature page is attached to any other counterpart
identical thereto except having additional signature pages executed by other
parties to this Fourth Amendment attached thereto.
d.Except as amended and/or modified by this Fourth Amendment, the Lease is
hereby ratified and confirmed and all other terms of the Lease shall remain in
full force and effect, unaltered and unchanged by this Fourth Amendment. In the
event of any conflict between the provisions of this Fourth Amendment and the
provisions of the Lease, the provisions of this Fourth Amendment shall prevail.
Whether or not specifically amended by this Fourth Amendment, all of the terms
and provisions of the Lease are hereby amended to the extent necessary to give
effect to the purpose and intent of this Fourth Amendment.
[Signatures are on next page]

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IN WITNESS WHEREOF, the parties hereto have executed this Fourth Amendment as of
the day and year first above written.
TENANT:
PROTHENA BIOSCIENCES, INC.,
a Delaware corporation
 
 
 
/s/ Dale B. Schenk
By:
Dale B. Schenk
Its:
President and Chief Executive Officer

LANDLORD:
ARE-SAN FRANCISCO NO. 33, LLC,
a Delaware limited liability corporation

By:
ALEXANDRIA REAL ESTATE EQUITIES, L.P., a Delaware limited partnership,

managing member
By:    ARE-QRS CORP.,
a Maryland corporation,
general partner
 
/s/ Eric S. Johnson
By:
Eric S. Johnson
Its:
Vice President, Real Estate Legal Affairs

                    

CONSENT OF GUARANTOR:
The undersigned, being the Guarantor under that certain Guaranty of Lease dated
as of December 21, 2012 (the “Guaranty”) made by the undersigned in favor of
Landlord, hereby consents to all of the terms, provisions, covenants and
conditions set forth in this Fourth Amendment, and to the execution and delivery
of this Fourth Amendment by Tenant. Guarantor hereby agrees that all of the
guarantees, terms, covenants, conditions, representations and warranties set
forth in the Guaranty are in full force and effect for the benefit of Landlord
and are not amended or modified by the terms of this Fourth Amendment, and
Guarantor hereby expressly affirms and confirms its obligations, guarantees and
liabilities under the Guaranty.

Witness the execution and delivery hereof as an instrument under seal as of the
30th day of November, 2013.

PROTHENA CORPORATION PLC,
a public limited company organized under the laws of
Ireland (Registration No. 518146)

                        
 
/s/ Shane Cook
By:
Shane Cook
Its:
Director

                        

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EXHIBIT A

Third Expansion Premises

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EXHIBIT B
Third Expansion Premises Work Letter
THIS THIRD EXPANSION PREMISES WORK LETTER dated November 30, 2013 (this "Third
Expansion Premises Work Letter") is made and entered into by and between ARE-SAN
FRANCISCO NO. 33, LLC, a Delaware limited liability company ("Landlord"), and
PROTHENA BIOSCIENCES, INC., a Delaware corporation, and is attached to and made
a part of that certain Lease Agreement dated as of March 18, 2010, as amended by
that certain Letter Agreement dated as of March 18, 2010, as further amended by
that certain First Amendment to Lease dated November 18, 2011, as further
amended by that certain Second Amendment to Lease dated as of June 1, 2012, as
further amended by that certain Third Amendment to Lease dated as of October 3,
2012, and as further amended by that certain Fourth Amendment to Lease dated of
even date herewith (as amended, 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.
1.General Requirements.
(a)Tenant's Authorized Representative. Tenant designates Tran Nguyen or Karin
Walker (either of them acting individually, a "Tenant's Representative")are the
only persons authorized to act for Tenant pursuant to this Third Expansion
Premises 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 Third Expansion Premises Work Letter
unless such Communication is in writing from a 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 Todd Miller and
Anup Kiwalkar (any such individual acting alone, "Landlord's Representative") as
the only persons authorized to act for Landlord pursuant to this Third Expansion
Premises 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 Third Expansion Premises Work Letter unless
such Communication is in writing from Landlord's Representative. Landlord may
change any 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. The TI Allowance may be used to pay the cost of the
Architect, general contractor and sub-contractors.
2.Tenant Improvements.
(a)Tenant Improvements Defined. As used herein, "Tenant Improvements" shall mean
all improvements to the Third Expansion Premises (and to any other portion of
the Third Expansion Premises reflected in the Space Plans, as approved by
Landlord) of a fixed and permanent nature as shown on the TI Construction
Drawings, as defined in Section 2(c) below. 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 Third Expansion Premises for
Tenant's use and occupancy.
(b)Tenant's Space Plans. Tenant shall deliver to Landlord schematic drawings and
outline specifications (the "Space Plans") detailing Tenant's requirements for
the Tenant Improvements prior to

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the commencement by Tenant of the construction of the Tenant Improvements. Not
more than 15 days thereafter, Landlord shall deliver to Tenant the written
objections, questions or comments of Landlord and the TI Architect with regard
to such Space Plans. Tenant shall cause the Space Plans to be revised to address
such written comments and shall resubmit said drawings to Landlord for approval
within 15 days thereafter. Such process shall continue until Landlord has
approved the Space Plans for the Tenant Improvements.
(c)Working Drawings. Not later than 30 days following the approval of the Space
Plans 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 applicable Tenant Improvements ("TI Construction Drawings"), which TI
Construction Drawings shall be prepared substantially in accordance with the
Space Plan. Tenant shall be solely responsible for ensuring that the TI
Construction Drawings reflect Tenant's requirements for such portion of 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 applicable Space Plan. 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 applicable Space Plan,
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 Landlord-approved 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 any portion
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 disputed portion 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 Allowance (as defined
in Section 5(a) below), and (iii) Tenant's decision will not affect the
structural components of the Building or any Building Systems. 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.
Notwithstanding anything to the contrary contained herein, Landlord shall have
the right to make final decisions, in Landlord’s sole and absolute subjective
discretion, with respect to matters concerning the exterior components, site
work, façade or other structural components of the Building or any Building
System.
3.Performance of the Tenant Improvements.
(a)Commencement and Permitting of the Tenant Improvements. Tenant shall commence
construction of the Tenant Improvements upon obtaining and delivering to
Landlord a building permit (the "TI Permit") authorizing the construction
thereof consistent with the TI Construction Drawings approved by Landlord. The
cost of obtaining the TI Permit required for the Tenant Improvements shall be
payable from the TI Allowance. Landlord shall assist Tenant in obtaining such TI
Permit(s). Prior to the commencement of any portion 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.

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(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 materially affects the operation of, or maintenance requirements
associated with, 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 Third Expansion 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 G704. For purposes of this Third Expansion Premises 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 material changes requested by Tenant to the Tenant Improvements
as depicted in any TI Construction Drawings approved by Landlord, 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. Proposed changes to the
Premises finishes shall not require Landlord’s approval.
(a)Tenant's Right to Request Changes. If Tenant shall request changes to any
Landlord-approved TI Construction Drawings ("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, 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 a schedule for
Tenant’s performance and completion of such Tenant Improvements (the
“Schedule”), and shall deliver a copy of each of the Budget and Schedule 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 and shall include a payment to Landlord of administrative rent
("Administrative Rent") in the amount of Landlord’s reasonable out-of-pocket
costs and expenses associated with Landlord’s engineering and architectural
review of the Space Plans and TI Construction Drawings (and any Changes thereto)
for any Tenant Improvements that affect the exterior components,

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site work, façade or other structural components of the Building or any Building
System, all of which shall be payable from the TI Allowance.
(b)TI Allowance. Landlord shall provide to Tenant a tenant improvement allowance
(collectively, the "TI Allowance") as follows:
1.    a "Tenant Improvement Allowance" in the maximum amount of $21.49     per
rentable square foot in the Third Expansion Premises, which is included in the
Base Rent set forth in the Lease; and
2.    an "Additional Tenant Improvement Allowance" in the maximum amount of
$15.00 per rentable square foot in the Third Expansion Premises, which shall, to
the extent used, result in TI Rent. Commencing on the Third Expansion Premises
Commencement Date, in addition to Base Rent, Tenant shall pay, on the first day
of each month, the amount necessary to fully amortize the portion of the
Additional Tenant Improvement Allowance actually funded by Landlord, if any, in
equal monthly payments with interest at a rate of 9% per annum over the
remaining balance of the Base Term (“TI Rent”). If any portion of the Additional
Tenant Improvement Allowance is funded after the Third Expansion Premises
Commencement Date, the monthly amount of TI Rent payable by Tenant shall be
adjusted in order to fully amortize such amounts funded after the Third
Expansion Premises Commencement Date in equal monthly payments at a rate of 9%
per annum over the then-remaining balance of the Base Term. Any unamortized
portion of the Additional Tenant Improvement Allowance shall be paid by Tenant
to Landlord with interest in a balloon payment upon the expiration or earlier
termination of the Base Term. Notwithstanding the foregoing, rather than having
Tenant pay the Additional Tenant Improvement Allowance actually disbursed as TI
Rent as provided above, Tenant may elect by delivery of written notice to
Landlord prior to the commencement of construction of the Tenant Improvements to
structure the payment by Tenant of the Additional Tenant Improvement Allowance
as debt which would be subject to and governed by a promissory note in form and
substance acceptable to Landlord in its sole and absolute discretion (“Note”)
which Note would provide, among other things, for the amount of the Additional
Tenant Improvement Allowance actually funded by Landlord to be fully amortized
and paid by Tenant to Landlord in equal monthly payments with interest at a rate
of 9% per annum over the remaining balance of the Base Term with a balloon
payment of the remaining principal and interest due upon the expiration or
earlier termination of the Base Term. Any failure by Tenant to pay any amounts
due under the Note shall constitute a Default under the Lease.
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 Tenant Improvement Allowance that is not disbursed
before December 1, 2018, or any portion of the Additional Tenant Improvement
Allowance that is not disbursed before June 30, 2016.
(c)Includable TI Costs. The TI Allowance shall be used solely for the payment of
design, permits and construction costs in connection with the construction of
the Tenant Improvements, including, without limitation, the cost of electrical
power and other utilities used in connection with the construction of the Tenant
Improvements, the cost of preparing the Space Plan and the TI Construction
Drawings, all costs set forth in the Budget, including Landlord's Administrative
Rent, and the cost of Changes (collectively, "TI Costs"). Notwithstanding
anything to the contrary contained herein, the TI Allowance shall not be used to
purchase any furniture, personal property or other non-Building system materials
or equipment, including, but not 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.
Notwithstanding anything to

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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, Landlord shall reimburse Tenant on a pro rata basis a
percentage of the TI Costs (equal to the percentage that the TI Allowance bears
to the total Budget, as the same may be amended from time to time, up to the
amount of the TI Allowance actually incurred by Tenant, not more frequently than
once a month, against a draw request in Landlord's standard form, containing
evidence of payment of such TI 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 construction of the Tenant
Improvements (and prior to any final disbursement of the TI Allowance), Tenant
shall deliver to Landlord: (i) sworn statements setting forth the names of all
contractors and first tier subcontractors who did the work of the Tenant
Improvements, 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 Third Expansion Premises; and (v) copies of all operation and
maintenance manuals and warranties affecting such Tenant Improvements.
6.Miscellaneous.
(a)Consents. Whenever consent or approval of either party is required under this
Third Expansion Premises 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 Third Expansion
Premises 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.

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