Lease for Property Dated March 1, 2005



 EXHIBIT 10.31 
  
 CHINA BASIN LANDING 
  
 OFFICE LEASE 
  
 This Office Lease (the “Lease”), dated as of the date set forth in Section 1 of the Summary of Basic Lease Information (the
“Summary”), below, is made by and between STOCKBRIDGE/MCC-CHINA BASIN L.L.C., a Delaware limited liability company (“Landlord”), and SIRNA THERAPEUTICS, INC., a Delaware corporation (“Tenant”).

  
 SUMMARY OF BASIC LEASE INFORMATION 
  
  

					
	 TERMS OF LEASE

	  	 DESCRIPTION


	 1.      
	 	 Date:
	  	March 1, 2005
			
	 2.      
	 	 Premises(Article1).
	  	 
			
	 	 	 2.1    Building:
	  	 Wharfside Building, China Basin Landing,
 185 Berry
Street, San Francisco, California 94107

			
	 	 	 2.2    Premises:
	  	Approximately 4,350 rentable square feet of space located in Suite 6504 on the sixth (6th) floor of the Building, as further set forth in Exhibit A to this Lease.
			
	 3.
	 	 Lease Term
 (Article 2).
	  	 
			
	 	 	 3.1    Length of Term:
	  	Two (2) years.
			
	 	 	 3.2    Lease Commencement Date:
	  	April 1, 2005.
			
	 	 	 3.3    Lease Expiration Date:
	  	March 31, 2007.
			
	 4.
	 	 Base Rent (Article 3):
	  	 

  

												
	  
  
 Period of
 Lease Term

	  	 Annual
 Base Rent

	  	 Monthly
 Installment
 of Base Rent

	  	 Annual
 Rental Rate
 per Rentable
 Square Foot


	 April 1, 2005 – May 1, 2005
	  	$	0.00	  	$	0.00	  	$	0.00
				
	 May 1, 2005 – March 31, 2006
	  	$	108,750.00	  	$	9,062.50	  	$	25.00
				
	 April 1, 2006 – March 31, 2007
	  	$	113,100.00	  	$	9,425.00	  	$	26.00

  

					
	 5.
	 	 Base Year
 (Article 4):
	  	Calendar year 2005.
			
	 6.
	 	 Tenant’s Share
 (Article 4):
	  	0.60%.
			
	 7.
	 	 Permitted Use
 (Article 5):
	  	General office use consistent with a first-class office building

  


					
	 	 	 	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]











					
	 8.
	 	 Security Deposit
 (Article 21):
	  	$9,425.00.
			
	 9.
	 	 Parking Passes
 (Article 28):
	  	Two (2) unreserved parking passes.
			
	 10.
	 	 Address of Tenant (Section 29.18):
	  	 Sirna Therapeutics, Inc.
 2950 Wilderness
Place
 Boulder, Colorado 80301
 Attention: Martin Schmieg, Chief
Financial Officer
 (Prior to Lease Commencement Date)
  
 and
  
 Sirna Therapeutics, Inc.
 China Basin Landing
 185 Berry
Street, Suite 6504
 San Francisco, California 94107
 Attention:
Martin Schmieg, Chief Financial Officer
 (After Lease Commencement Date)

			
	 11.
	 	 Address of Landlord
 (Section
29.18):
	  	 McCarthy Cook & Co., LLC
 China Basin
Landing
 185 Berry Street, Suite 140
 San Francisco, California
94107
 Attention: General Manager
  
 with copies to:
  
 McCarthy Cook & Co., LLC
 5750 Wilshire Boulevard
 Los Angeles, California 90036
 Attention: Edward W. Cook III
  
 and
  
 Allen Matkins Leck Gamble & Mallory LLP
 1901 Avenue of the Stars, Suite
1800
 Los Angeles, California 90067
 Attention: Anton N. Natsis,
Esq.

			
	 12.
	 	 Broker(s)
 (Section 29.24):
	  	 GVA Whitney Cressman
 505 Sansome Street, Suite
300
 San Francisco, California 94111


  


					
	 	 	-2-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 ARTICLE 1 
  

PREMISES, BUILDING, PROJECT, AND COMMON AREAS 
  
 1.1 Premises, Building, Project and Common Areas. 
  

1.1.1 The Premises. Landlord hereby leases to Tenant and Tenant hereby leases from Landlord the premises set forth in Section 2.2 of the
Summary (the “Premises”). The outline of the Premises is set forth in Exhibit A attached hereto and each floor or floors of the Premises has the number of rentable square feet as set forth in Section 2.2 of the
Summary. Landlord and Tenant hereby stipulate and agree that the rentable area of the Premises is as set forth in Section 2.2 of the Summary, and such square footage shall not be subject to remeasurement or modification. The parties hereto agree
that the lease of the Premises is upon and subject to the terms, covenants and conditions herein set forth, and Tenant and Landlord covenant as a material part of the consideration for this Lease to keep and perform each and all of such terms,
covenants and conditions by them to be kept and performed and that this Lease is made upon the condition of such performance. The parties hereto hereby acknowledge that the purpose of Exhibit A is to show the approximate location of
the Premises in the “Building,” as that term is defined in Section 1.1.2, below, only, and such Exhibit is not meant to constitute an agreement, representation or warranty as to the construction of the Premises, the precise area thereof or
the specific location of the “Common Areas,” as that term is defined in Section 1.1.3, below, or the elements thereof or of the accessways to the Premises or the “Project,” as that term is defined in Section 1.1.2, below. Except
as specifically set forth in this Lease, Landlord shall not be obligated to provide or pay for any improvement work or services related to the improvement of the Premises. Tenant also acknowledges that neither Landlord nor any agent of Landlord has
made any representation or warranty regarding the condition of the Premises, the Building or the Project or with respect to the suitability of any of the foregoing for the conduct of Tenant’s business, except as specifically set forth in this
Lease. The taking of possession of the Premises by Tenant shall conclusively establish that the Premises and the Building were at such time in good and sanitary order, condition and repair. 
  
 1.1.2 The Building and The Project. The Premises are a part of
the building set forth in Section 2.1 of the Summary (the “Building”). The Building is part of an office project known as “China Basin Landing.” The term “Project,” as used in this Lease, shall mean
(i) the Building and the Common Areas, (ii) the land (which is improved with landscaping, subterranean parking facilities and other improvements) upon which the Building and the Common Areas are located, and (iii) the other office building located
adjacent to the Building and the land upon which such adjacent office building is located, and (iv) at Landlord’s discretion, any additional real property, areas, land, buildings or other improvements added thereto outside of the Project;
provided that Tenant’s financial obligations are not materially increased as a result thereof. 
  
 1.1.3 Common Areas. Tenant shall have the non-exclusive right to use in common with other tenants in the Project, and subject to the rules
and regulations referred to in Article 5 of this Lease, those portions of the Project which are provided, from time to time, for use in common by Landlord, Tenant and any other tenants of the Project (such areas, together with such other portions of
the Project designated by Landlord, in its discretion, including certain areas designated for the exclusive use of certain tenants, or to be shared by Landlord and certain tenants, are collectively referred to herein as the “Common
Areas”). The Common Areas shall consist of the “Project Common Areas” and the “Building Common Areas.” The term “Project Common Areas,” as used in this Lease, shall mean the portion of the Project
designated as such by Landlord. The term “Building Common Areas,” as used in this Lease, shall mean the portions of the Common Areas located within the Building designated as such by Landlord. The manner in which the Common Areas
are maintained and operated shall be at the sole discretion of Landlord and the use thereof shall be subject to such rules, regulations and restrictions as Landlord may make from time to time. Landlord reserves the right to close temporarily, make
alterations or additions to, or change the location of elements of the Project and the Common Areas; provided that Landlord shall use commercially reasonable efforts to minimize interference with Tenant’s use of, and access to, the Premises and
the Common Areas. 
  
 1.2 Expansion of the Premises.
In the event Tenant desires to lease additional space in the Project, Tenant shall notify Landlord of Tenant’s space requirement and Landlord shall use commercially reasonable efforts to cooperate with Tenant to find suitable additional space
in the 
  


					
	 	 	-3-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 Project, subject to availability. Such additional space may be added to the Premises, or, upon agreement by the parties,
may be provided in connection with a relocation of the Premises, at Tenant’s sole cost and expense, to other larger space in the Project. Tenant’s lease of any space in the Building other than the Premises shall be subject to the terms of
this Lease, provided that Tenant shall pay Rent for such expansion or relocation space in an amount equal to the then-current fair market value for such space, as agreed to by the parties, in their sole and absolute discretion. Notwithstanding
anything herein to the contrary, in the event the Premises are altered in accordance with the terms of this Section 1.2, this Lease shall be amended to reflect the addition of any such expansion space to the Premises or such relocation of the
Premises. At such time, this Lease shall also be amended to include any additional provisions as mutually agreed upon by the parties, in their sole and absolute discretion, including, should the expanded and/or relocated premises include a
laboratory, the addition or deletion of certain provisions to adapt this Lease to such modified use. Landlord and Tenant hereby acknowledge and agree that nothing contained in this Section 1.2 shall be construed as an obligation of either
Landlord or Tenant to increase the size of the Premises or to agree to a relocation of the Premises, and the same shall only occur to the extent each party elects to consummate such a transaction, in the exercise of their respective sole and
absolute discretion. Any such transaction shall be commemorated in a written amendment to this Lease. 
  
 ARTICLE 2 
  
 INITIAL LEASE TERM; OPTION TERM 
  
 2.1
Initial Lease Term. The terms and provisions of this Lease shall be effective as of the date of this Lease. The term of this Lease (the “Lease Term”) shall be as set forth in Section 3.1 of the Summary, shall commence
on the date set forth in Section 3.2 of the Summary (the “Lease Commencement Date”), and shall terminate on the date set forth in Section 3.3 of the Summary (the “Lease Expiration Date”) unless this Lease is sooner
terminated as hereinafter provided. For purposes of this Lease, the term “Lease Year” shall mean each consecutive twelve (12) month period during the Lease Term; provided, however, that the first Lease Year shall commence on the
Lease Commencement Date and end on the last day of the eleventh month thereafter and the second and each succeeding Lease Year shall commence on the first day of the next calendar month; and further provided that the last Lease Year shall end on the
Lease Expiration Date. At any time during the Lease Term, Landlord may deliver to Tenant a notice in the form as set forth in Exhibit C, attached hereto, as a confirmation only of the information set forth therein, which Tenant shall
execute and return to Landlord within five (5) days of receipt thereof. 
  
 2.2 Option Term. 
  
 2.2.1 Option
Right. Landlord hereby grants the Tenant named in the Summary (“Original Tenant“), one (1) option to extend the Lease Term for a period of one (1) year (the “Option Term“), which option shall be exercisable
only by written notice delivered by Tenant to Landlord as provided below, provided that, as of the date of delivery of such notice, Tenant is not in default under this Lease. Upon the proper exercise of such option to extend, and provided that, as
of the end of the initial Lease Term, Tenant is not in default under this Lease, the Lease Term, as it applies to the Premises, shall be extended for a period of one (1) year. The rights contained in this Section 2.2 shall be personal to the
Original Tenant and may only be exercised by the Original Tenant (and not any assignee, sublessee or other transferee of the Original Tenant’s interest in this Lease) if the Original Tenant occupies the entire Premises. 
  
 2.2.2 Option Rent. The rent payable by Tenant during the Option
Term (the “Option Rent“) shall be equal to the rent (including additional rent and considering any “base year” or “expense stop” applicable thereto), including all escalations, at which tenants, as of the
commencement of the Option Term, are leasing non-sublease, non-encumbered, non-equity, non-renewal, non-expansion space comparable in size, location and quality to the Premises for a comparable term, which comparable space is located in the
Building, taking into consideration the following concessions: (a) rental abatement concessions, if any, being granted such tenants in connection with such comparable spaces and (b) tenant improvements or allowances provided or to be provided for
such comparable space, taking into account, and deducting the value of, the existing improvements in the Premises, such value to be based upon the age, quality and layout of the improvements and the extent to which the same could be utilized by
Tenant based upon the fact that the precise tenant improvements existing in the Premises are specifically suitable to 
  


					
	 	 	-4-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 Tenant; provided, however, that in calculating the Option Rent, no consideration shall be given to (i) the fact that
Landlord is or is not required to pay a real estate brokerage commission in connection with Tenant’s exercise of its right to lease the Premises during the Option Term, and (ii) any period of rental abatement, if any, granted to tenants in
comparable transactions in connection with the design, permitting and construction of tenant improvements in such comparable spaces. 
  
 2.2.3 Exercise of Options. The option contained in this Section 2.2 shall be exercised by Tenant, if at all, only in the following
manner: (i) Tenant shall deliver written notice to Landlord not more than twelve (12) months nor less than ten (10) months prior to the expiration of the initial Lease Term, stating that Tenant is interested in exercising its option; (ii) Landlord,
after receipt of Tenant’s notice, shall deliver notice (the “Option Rent Notice”) to Tenant not less than eight (8) months prior to the expiration of the initial Lease Term, setting forth the Option Rent; and (iii) if Tenant
wishes to exercise such option, Tenant shall, on or before the earlier of (A) the date occurring seven (7) months prior to the expiration of the initial Lease Term, and (B) the date occurring thirty (30) days after Tenant’s receipt of the
Option Rent Notice, exercise the option by delivering written notice thereof to Landlord. 
  
 ARTICLE 3 
  
 BASE
RENT 
  
 Tenant shall pay, without prior notice or demand,
to Landlord or Landlord’s agent at the address set forth in Section 11 of the Summary, or, at andlord’s option, at such other place as Landlord may from time to time designate in writing, not less than thirty (30) days prior to the
effectiveness of such address change, by a check for currency which, at the time of payment, is legal tender for private or public debts in the United States of America, base rent (“Base Rent”) as set forth in Section 4 of the
Summary, payable in equal monthly installments as set forth in Section 4 of the Summary in advance on or before the first day of each and every calendar month during the Lease Term, without any setoff or deduction whatsoever. The Base Rent for the
first full month of the Lease Term which occurs after the expiration of any free rent period shall be paid at the time of Tenant’s execution of this Lease. If any Rent payment date (including the Lease Commencement Date) falls on a day of the
month other than the first day of such month or if any payment of Rent is for a period which is shorter than one month, the Rent for any fractional month shall accrue on a daily basis for the period from the date such payment is due to the end of
such calendar month or to the end of the Lease Term at a rate per day which is equal to 1/365 of the applicable annual Rent. All other payments or adjustments required to be made under the terms of this Lease that require proration on a time basis
shall be prorated on the same basis. 
  
 ARTICLE 4

  
 ADDITIONAL RENT 
  
 4.1 General Terms. In addition to paying the Base Rent
specified in Article 3 of this Lease, Tenant shall pay “Tenant’s Share” of the annual “Direct Expenses,” as those terms are defined in Sections 4.2.6 and 4.2.2 of this Lease, respectively, which are in excess of the amount
of Direct Expenses applicable to the “Base Year,” as that term is defined in Section 4.2.1, below; provided, however, that in no event shall any decrease in Direct Expenses for any “Expense Year,” as that term is defined in
Section 4.2.e below, below Direct Expenses for the Base Year entitle Tenant to any decrease in Base Rent or any credit against sums due under this Lease. Such payments by Tenant, together with any and all other amounts payable by Tenant to Landlord
pursuant to the terms of this Lease, are hereinafter collectively referred to as the “Additional Rent”, and the Base Rent and the Additional Rent are herein collectively referred to as “Rent.” All amounts due under
this Article 4 as Additional Rent shall be payable for the same periods and in the same manner as the Base Rent. Without limitation on other obligations of Tenant which survive the expiration of the Lease Term, the obligations of Tenant to pay the
Additional Rent provided for in this Article 4 shall survive the expiration of the Lease Term; provided that Tenant’s obligations with respect to Additional Rent are for amounts which arise or accrue during the Lease Term only. 
  
 4.2 Definitions of Key Terms Relating to Additional Rent. As
used in this Article 4, the following terms shall have the meanings hereinafter set forth: 
  
 4.2.1 “Base Year” shall mean the period set forth in Section 5 of the Summary. 
  


					
	 	 	-5-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 4.2.2 “Direct Expenses” shall mean “Operating Expenses” and “Tax
Expenses.” 
  
 4.2.3 “Expense Year” shall
mean each calendar year in which any portion of the Lease Term falls, through and including the calendar year in which the Lease Term expires, provided that Landlord, upon notice to Tenant, may change the Expense Year from time to time to any other
twelve (12) consecutive month period falling within the Lease Term, and, in the event of any such change, Tenant’s Share of Direct Expenses shall be equitably adjusted for any Expense Year involved in any such change. 
  
 4.2.4 “Operating Expenses” shall mean all expenses, costs
and amounts of every kind and nature which Landlord pays or accrues during any Expense Year because of or in connection with the ownership, management, maintenance, security, repair, replacement, restoration or operation of the Project, or any
portion thereof. Without limiting the generality of the foregoing, Operating Expenses shall specifically include any and all of the following: (i) the cost of supplying all utilities, the cost of operating, repairing, maintaining, and renovating the
utility, telephone, mechanical, sanitary, storm drainage, and elevator systems, and the cost of maintenance and service contracts in connection therewith; (ii) the cost of licenses, certificates, permits and inspections and the cost of contesting
any governmental enactments which may affect Operating Expenses, and the costs incurred in connection with a transportation system management program or similar program; (iii) the cost of all insurance carried by Landlord in connection with the
Project; (iv) the cost of landscaping, relamping, and all supplies, tools, equipment and materials used in the operation, repair and maintenance of the Project, or any portion thereof; (v) costs incurred in connection with the parking areas
servicing the Building; (vi) fees and other costs, including management fees, consulting fees, legal fees and accounting fees, of all contractors and consultants in connection with the management, operation, maintenance and repair of the Project;
(vii) payments under any equipment rental agreements and the fair rental value of any management office space; (viii) wages, salaries and other compensation and benefits, including taxes levied thereon, of all persons engaged in the operation,
management, maintenance and security of the Project; (ix) costs under any instrument pertaining to the sharing of costs by the Project; (x) operation, repair, maintenance and replacement of all systems and equipment and components thereof of the
Building; (xi) the cost of janitorial, alarm, security and other services, replacement of wall and floor coverings, ceiling tiles and fixtures in common areas, maintenance and replacement of curbs and walkways, exterior windows and walls, repair to
roofs and re-roofing, waterproofing and sealing of garage, foundation and basement areas; (xii) amortization (including interest on the unamortized cost) of the cost of acquiring or the rental expense of personal property used in the maintenance,
operation and repair of the Project, or any portion thereof; (xiii) the cost of capital improvements or other costs incurred in connection with the Project (A) which are intended to effect economies in the operation or maintenance of the Project, or
any portion thereof, to the extent of the reasonably anticipated cost savings, (B) that are required to comply with present or anticipated conservation programs, (C) which are replacements or modifications of nonstructural items located in the
Common Areas required to keep the Common Areas in good order or condition, or (D) that are required under any governmental law or regulation; provided, however, that any capital expenditure shall be amortized with interest over its useful life as
Landlord shall reasonably determine; (xiv) costs, fees, charges or assessments imposed by, or resulting from any mandate imposed on Landlord by, any federal, state or local government for fire and police protection, trash removal, community
services, or other services which do not constitute “Tax Expenses” as that term is defined in Section 4.2.5, below; and (xv) payments under any easement, license, operating agreement, declaration, restrictive covenant, or instrument
pertaining to the sharing of costs by the Building. 
  
 Notwithstanding the foregoing, for purposes of this Lease, Operating Expenses shall not, however, include any of the following: 
  
 (a) costs, including legal fees, space planners’ fees, advertising and promotional expenses (except as otherwise set forth above), and brokerage fees
incurred in connection with the original construction or development, or original or future leasing of the Project, and costs, including permit, license and inspection costs, incurred with respect to the installation of tenant improvements made for
new tenants initially occupying space in the Project 
  


					
	 	 	-6-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 after the Lease Commencement Date or incurred in renovating or otherwise improving, decorating, painting or redecorating
vacant space for tenants or other occupants of the Project (excluding, however, such costs relating to any common areas of the Project or parking facilities); 
  

(b) except as set forth in items (xii) and (xiii) above, depreciation, interest and principal payments on mortgages and other debt costs, if any,
penalties and interest, costs of capital repairs and alterations, and costs of capital improvements and equipment; 
  
 (c) costs for which the Landlord is reimbursed by any tenant or occupant of the Project or by insurance by its carrier or any tenant’s carrier or by
anyone else, and electric power costs for which any tenant directly contracts with the local public service company; 
  
 (d) any bad debt loss, rent loss, or reserves for bad debts or rent loss; 
  
 (e) costs associated with the operation of the business of the partnership or entity which constitutes the Landlord, as the
same are distinguished from the costs of operation of the Project (which shall specifically include, but not be limited to, accounting costs associated with the operation of the Project). Costs associated with the operation of the business of the
partnership or entity which constitutes the Landlord include, without limitation, costs of partnership accounting and legal matters, costs of defending any lawsuits with any mortgagee (except as the actions of the Tenant may be in issue), costs of
selling, syndicating, financing, mortgaging or hypothecating any of the Landlord’s interest in the Project, and costs incurred in connection with any disputes between Landlord and its employees, between Landlord and Project management, or
between Landlord and other tenants or occupants; 
  
 (f) the wages
and benefits of any employee who does not devote substantially all of his or her employed time to the Project unless such wages and benefits are prorated to reflect time spent on operating and managing the Project vis-a-vis time spent on matters
unrelated to operating and managing the Project; provided, that in no event shall Operating Expenses for purposes of this Lease include wages and/or benefits attributable to personnel above the level of Project manager; 
  
 (g) amount paid as ground rental for the Project by the Landlord; 

 
 (h) any compensation paid to clerks, attendants or other persons in
commercial concessions operated by the Landlord, provided that any compensation paid to any concierge at the Project shall be includable as an Operating Expense; 
  
 (i) rentals and other related expenses incurred in leasing air conditioning systems, elevators or other equipment which if
purchased the cost of which would be excluded from Operating Expenses as a capital cost, except equipment not affixed to the Project which is used in providing janitorial or similar services and, further excepting from this exclusion such equipment
rented or leased to remedy or ameliorate an emergency condition in the Project ; 
  
 (j) all items and services for which Tenant or any other tenant in the Project reimburses Landlord or which Landlord provides selectively to one or more tenants (other than Tenant) without reimbursement; 

 
 (k) rent for any office space occupied by Project management personnel to
the extent the size or rental rate of such office space exceeds the size or fair market rental value of office space occupied by management personnel of the comparable buildings in the vicinity of the Building, with adjustment where appropriate for
the size of the applicable project; 
  
 (l) any bad debt loss,
rent loss, or reserves for bad debts or rent loss or any reserves of any kind; 
  
 (m) any amount included in Tax Expenses; and 
  
 (n) costs of any charitable or political contributions made by Landlord. 
  
 If Landlord is not furnishing any particular work or service (the cost of which, if performed by Landlord, would be included in Operating Expenses) to a
tenant who has undertaken to perform such work or service in lieu of the performance thereof by Landlord, 
  


					
	 	 	-7-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 Operating Expenses shall be deemed to be increased by an amount equal to the additional Operating Expenses which would
reasonably have been incurred during such period by Landlord if it had at its own expense furnished such work or service to such tenant. If the Project is not at least ninety-five percent (95%) occupied during all or a portion of the Base Year or
any Expense Year, Landlord shall make an appropriate adjustment to the components of Operating Expenses for such year to determine the amount of Operating Expenses that would have been incurred had the Project been ninety-five percent (95%)
occupied; and the amount so determined shall be deemed to have been the amount of Operating Expenses for such year. Operating Expenses for the Base Year shall include market-wide labor-rate increases due to extraordinary circumstances, including,
but not limited to, boycotts and strikes, and utility rate increases due to extraordinary circumstances including, but not limited to, conservation surcharges, boycotts, embargoes or other shortages, or amortized costs relating to capital
improvements; provided, however, that at such time as any such particular assessments, charges, costs or fees are no longer included in Operating Expenses, such particular assessments, charges, costs or fees shall be excluded from the Base Year
calculation of Operating Expenses. 
  
 4.2.5 Taxes.

  
 4.2.5.1 “Tax Expenses” shall mean all
federal, state, county, or local governmental or municipal taxes, fees, charges or other impositions of every kind and nature, whether general, special, ordinary or extraordinary, (including, without limitation, real estate taxes, general and
special assessments, transit taxes, leasehold taxes or taxes based upon the receipt of rent, including gross receipts or sales taxes applicable to the receipt of rent, unless required to be paid by Tenant, personal property taxes imposed upon the
fixtures, machinery, equipment, apparatus, systems and equipment, appurtenances, furniture and other personal property used in connection with the Project, or any portion thereof), which shall be paid or accrued during any Expense Year (without
regard to any different fiscal year used by such governmental or municipal authority) because of or in connection with the ownership, leasing and operation of the Project, or any portion thereof. 
  
 4.2.5.2 Tax Expenses shall include, without limitation: (i) Any tax on the
rent, right to rent or other income from the Project, or any portion thereof, or as against the business of leasing the Project, or any portion thereof; (ii) Any assessment, tax, fee, levy or charge in addition to, or in substitution, partially or
totally, of any assessment, tax, fee, levy or charge previously included within the definition of real property tax, it being acknowledged by Tenant and Landlord that Proposition 13 was adopted by the voters of the State of California in the June
1978 election (“Proposition 13”) and that assessments, taxes, fees, levies and charges may be imposed by governmental agencies for such services as fire protection, street, sidewalk and road maintenance, refuse removal and for other
governmental services formerly provided without charge to property owners or occupants, and, in further recognition of the decrease in the level and quality of governmental services and amenities as a result of Proposition 13, Tax Expenses shall
also include any governmental or private assessments or the Project’s contribution towards a governmental or private cost-sharing agreement for the purpose of augmenting or improving the quality of services and amenities normally provided by
governmental agencies; (iii) Any assessment, tax, fee, levy, or charge allocable to or measured by the area of the Premises or the Rent payable hereunder, including, without limitation, any business or gross income tax or excise tax with respect to
the receipt of such rent, or upon or with respect to the possession, leasing, operating, management, maintenance, alteration, repair, use or occupancy by Tenant of the Premises, or any portion thereof; and (iv) Any assessment, tax, fee, levy or
charge, upon this transaction or any document to which Tenant is a party, creating or transferring an interest or an estate in the Premises. 
  
 4.2.5.3 Any costs and expenses (including, without limitation, reasonable attorneys’ fees) incurred in attempting to protest, reduce or minimize Tax
Expenses shall be included in Tax Expenses in the Expense Year such expenses are paid. Tax refunds shall be credited against Tax Expenses and refunded to Tenant regardless of when received, based on the Expense Year to which the refund is
applicable, provided that in no event shall the amount to be refunded to Tenant for any such Expense Year exceed the total amount paid by Tenant as Additional Rent under this Article 4 for such Expense Year. If Tax Expenses for any period during the
Lease Term or any extension thereof are increased after payment thereof for any reason, including, without limitation, error or reassessment by applicable governmental or municipal authorities, Tenant shall pay Landlord upon demand Tenant’s
Share of any such increased Tax Expenses included by Landlord as Building Tax Expenses pursuant to the terms of 
  


					
	 	 	-8-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 this Lease. Notwithstanding anything to the contrary contained in this Section 4.2.5 (except as set forth in Section
4.2.5.1, above), there shall be excluded from Tax Expenses (i) all 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, receipts or income attributable to operations at the Project), (ii) any items included as Operating Expenses, and (iii) any items paid by Tenant under Section 4.5 of this
Lease. 
  
 4.2.5.4 The amount of Tax Expenses for the Base Year
attributable to the valuation of the Project, inclusive of tenant improvements, shall be known as “Base Taxes”. If in any comparison year subsequent to the Base Year, the amount of Tax Expenses decreases below the amount of Base Taxes,
then for purposes of all subsequent comparison years, including the comparison year in which such decrease in Tax Expenses occurred, the Base Taxes, and therefore the Base Year, shall be decreased by an amount equal to the decrease in Tax Expenses.

  
 4.2.6 “Tenant’s Share” shall mean the
percentage set forth in Section 6 of the Summary. 
  
 4.3
Allocation of Direct Expenses. 
  
 4.3.1
Method of Allocation. The parties acknowledge that the Building is a part of a multi-building project and that the costs and expenses incurred in connection with the Project (i.e. the Direct Expenses) are an aggregate of the Building
and other buildings in the Project. 
  
 4.3.2 Cost
Pools. Landlord shall have the right, from time to time, to equitably allocate some or all of the Direct Expenses for the Project among different portions or occupants of the Project (the “Cost Pools”), in Landlord’s
discretion. Such Cost Pools may include, but shall not be limited to, the office space tenants of a building of the Project or of the Project, and the retail space tenants of a building of the Project or of the Project. The Direct Expenses within
each such Cost Pool shall be allocated and charged to the tenants as determined by Landlord in accordance with sound real estate management principles. 
  
 4.4 Calculation and Payment of Additional Rent. If for any Expense Year ending or commencing within the Lease Term, Tenant’s Share of
Direct Expenses for such Expense Year exceeds Tenant’s Share of Direct Expenses applicable to the Base Year, then Tenant shall pay to Landlord, in the manner set forth in Section 4.4.1, below, and as Additional Rent, an amount equal to the
excess (the “Excess”). 
  
 4.4.1 Statement
of Actual Direct Expenses and Payment by Tenant. Landlord shall give to Tenant following the end of each Expense Year, and prior to the expiration fo the following Expense Year, a statement (the “Statement”) which shall
state the Direct Expenses incurred or accrued for such preceding Expense Year, and which shall indicate the amount of the Excess. Upon receipt of the Statement for each Expense Year commencing or ending during the Lease Term, if an Excess is
present, Tenant shall pay, with its next installment of Base Rent due, the full amount of the Excess for such Expense Year, less the amounts, if any, paid during such Expense Year as “Estimated Excess,” as that term is defined in Section
4.4.2, below. The failure of Landlord to timely furnish the Statement for any Expense Year shall not prejudice Landlord or Tenant from enforcing its rights under this Article 4. Even though the Lease Term has expired and Tenant has vacated the
Premises, when the final determination is made of Tenant’s Share of Direct Expenses for the Expense Year in which this Lease terminates, if an Excess is present, Tenant shall, within ten (10) days following receipt of billing, pay to Landlord
such amount. The provisions of this Section 4.4.1 shall survive the expiration or earlier termination of the Lease Term. 
  
 4.4.2 Statement of Estimated Direct Expenses. In addition, Landlord shall endeavor to give Tenant a yearly expense estimate statement (the
“Estimate Statement”) which shall set forth Landlord’s reasonable estimate (the “Estimate”) of what the total amount of Direct Expenses for the then-current Expense Year shall be and the estimated excess (the
“Estimated Excess”) as calculated by comparing the Direct Expenses for such Expense Year, which shall be based upon the Estimate, to the amount of Direct Expenses for the Base Year. The failure of Landlord to timely furnish the
Estimate Statement for any Expense Year shall not preclude 
  


					
	 	 	-9-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 Landlord from enforcing its rights to collect any Estimated Excess under this Article 4, nor shall Landlord be prohibited
from revising any Estimate Statement or Estimated Excess theretofore delivered to the extent necessary. Thereafter, Tenant shall pay, with its next installment of Base Rent due, a fraction of the Estimated Excess for the then-current Expense Year
(reduced by any amounts paid pursuant to the next to last sentence of this Section 4.4.2). Such fraction shall have as its numerator the number of months which have elapsed in such current Expense Year, including the month of such payment, and
twelve (12) as its denominator. Until a new Estimate Statement is furnished (which Landlord shall have the right to deliver to Tenant at any time), Tenant shall pay monthly, with the monthly Base Rent installments, an amount equal to one-twelfth
(1/12) of the total Estimated Excess set forth in the previous Estimate Statement delivered by Landlord to Tenant. 
  
 4.5 Taxes and Other Charges for Which Tenant Is Directly Responsible. 
  
 4.5.1 Tenant shall be liable for and shall pay ten (10) days before delinquency, taxes levied against Tenant’s
equipment, furniture, fixtures and any other personal property located in or about the Premises. If any such taxes on Tenant’s equipment, furniture, fixtures and any other personal property are levied against Landlord or Landlord’s
property or if the assessed value of Landlord’s property is increased by the inclusion therein of a value placed upon such equipment, furniture, fixtures or any other personal property and if Landlord pays the taxes based upon such increased
assessment, which Landlord shall have the right to do regardless of the validity thereof but only under proper protest if requested by Tenant, Tenant shall upon demand repay to Landlord the taxes so levied against Landlord or the proportion of such
taxes resulting from such increase in the assessment, as the case may be. 
  
 4.5.2 If the tenant improvements in the Premises, whether installed and/or paid for by Landlord or Tenant and whether or not affixed to the real property so as to become a part thereof, are assessed for real property
tax purposes at a valuation higher than the valuation at which tenant improvements conforming to Landlord’s “building standard” in other space in the Building are assessed, then the Tax Expenses levied against Landlord or the property
by reason of such excess assessed valuation shall be deemed to be taxes levied against personal property of Tenant and shall be governed by the provisions of Section 4.5.1, above. 
  
 4.5.3 Notwithstanding any contrary provision herein, Tenant shall pay prior to delinquency any (i) rent tax or sales tax,
service tax, transfer tax or value added tax, or any other applicable tax on the rent or services herein or otherwise respecting this Lease, (ii) taxes assessed upon or with respect to the possession, leasing, operation, management, maintenance,
alteration, repair, use or occupancy by Tenant of the Premises or any portion of the Project, including the Project parking facility; or (iii) taxes assessed upon this transaction or any document to which Tenant is a party creating or transferring
an interest or an estate in the Premises. 
  
 ARTICLE 5

  
 USE OF PREMISES 
  
 5.1 Permitted Use. Tenant shall use the Premises solely for the
Permitted Use set forth in Section 7 of the Summary and Tenant shall not use or permit the Premises or the Project to be used for any other purpose or purposes whatsoever without the prior written consent of Landlord, which may be withheld in
Landlord’s sole discretion. 
  
 5.2 Prohibited
Uses. The uses prohibited under this Lease shall include, without limitation, use of the Premises or a portion thereof for (i) offices of any agency or bureau of the United States or any state or political subdivision thereof; (ii) offices
or agencies of any foreign governmental or political subdivision thereof; (iii) offices of any health care professionals or service organization (but excluding any health care professionals engaged in the business of life sciences research); (iv)
schools or other training facilities which are not ancillary to corporate, executive or professional office use; (v) retail or restaurant uses; or (vi) communications firms such as radio and/or television stations. Tenant shall not allow occupancy
density of use of the Premises which is greater than one (1) person for each 150 square feet of the Premises. Tenant further covenants and agrees that Tenant shall not use, or suffer or permit any person or persons to use, the Premises or any part
thereof for any use or purpose contrary to the provisions of the Rules and Regulations set forth in Exhibit D, attached hereto, or in violation of the laws of the 
  


					
	 	 	-10-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 United States of America, the State of California, or the ordinances, regulations or requirements of the local municipal
or county governing body or other lawful authorities having jurisdiction over the Project) including, without limitation, any such laws, ordinances, regulations or requirements relating to hazardous materials or substances, as those terms are
defined by applicable laws now or hereafter in effect. Tenant shall not do or permit anything to be done in or about the Premises which will in any way materially damage the reputation of the Project or obstruct or interfere with the rights of other
tenants or occupants of the Building, or injure or annoy them or use or allow the Premises to be used for any improper, unlawful or objectionable purpose, nor shall Tenant cause, maintain or permit any nuisance in, on or about the Premises. Tenant
shall comply with all recorded covenants, conditions, and restrictions now or hereafter affecting the Project and Landlord shall, upon request from Tenant, provide Tenant with copies of all recorded covenants, conditions and restrictions currently
affecting the Project and will notify Tenant and provide copies to Tenant of any future covenants, conditions, and restrictions affecting the Project. 
  
 ARTICLE 6 
  
 SERVICES AND UTILITIES 
  
 6.1 Standard Tenant Services. Landlord shall provide the following services on all days (unless otherwise stated below) during the Lease Term. 
  
 6.1.1 Subject to limitations imposed by all governmental rules, regulations
and guidelines applicable thereto, Landlord shall provide heating and air conditioning (“HVAC”) when necessary for normal office use in the Premises from 8:00 A.M. to 6:00 P.M. Monday through Friday (collectively, the
“Building Hours”), except for the date of observation of New Year’s Day, Memorial Day, Independence Day, Labor Day, Thanksgiving Day, Christmas Day and, at Landlord’s discretion, upon not less than thirty (30) days written
notice to Tenant, other locally or nationally recognized holidays (collectively, the “Holidays”). 
  
 6.1.2 Landlord shall provide adequate electrical wiring and facilities for connection to Building standard ceiling mounted lighting fixtures and
incidental use equipment, provided that Tenant’s consumption of electricity does not exceed 1 kilowatt/hour per usable square foot of the Premises per month, which electrical usage shall be subject to applicable laws and regulations, including
Title 24 of the California Code of Regulations. Tenant will design Tenant’s electrical system serving any equipment producing nonlinear electrical loads to accommodate such nonlinear electrical loads, including, but not limited to, oversizing
neutral conductors, derating transformers and/or providing power-line filters. Engineering plans shall include a calculation of Tenant’s fully connected electrical design load with and without demand factors and shall indicate the number of
watts of unmetered and submetered loads. Tenant shall bear the cost of replacement of lamps, starters and ballasts for non-Building standard lighting fixtures within the Premises. 
  
 6.1.3 Landlord shall provide city water from the regular Building outlets for pantry, drinking, lavatory and toilet purposes
in the Premises and the Building Common Areas. 
  
 6.1.4 Landlord
shall provide janitorial services to the Premises, except the date of observation of the Holidays, in and about the Premises and window washing services in a manner consistent with other comparable buildings in the vicinity of the Building.

  
 6.1.5 Landlord shall provide nonexclusive, non-attended
automatic passenger elevator service during the Building Hours, shall have one elevator available at all other times, and shall provide nonexclusive, non-attended automatic passenger escalator service during Building Hours only. 
  
 6.1.6 Landlord shall provide nonexclusive freight elevator service subject to
scheduling by Landlord. 
  
 Tenant shall cooperate fully with
Landlord at all times and abide by all regulations and requirements that Landlord may reasonably prescribe for the proper functioning and protection of the HVAC, electrical, mechanical and plumbing systems. 
  


					
	 	 	-11-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 6.2 Overstandard Tenant Use. Tenant shall not, without Landlord’s prior written
consent, use heat-generating machines, machines other than normal fractional horsepower office machines, or equipment or lighting other than Building standard lights in the Premises, which may affect the temperature otherwise maintained by the air
conditioning system or increase the water normally furnished for the Premises by Landlord pursuant to the terms of Section 6.1 of this Lease. If such consent is given, Landlord shall have the right to install supplementary air conditioning units or
other facilities in the Premises, including supplementary or additional metering devices, and the cost thereof, including the cost of installation, operation and maintenance, increased wear and tear on existing equipment and other similar charges,
shall be paid by Tenant to Landlord upon billing by Landlord. If Tenant uses water, electricity, heat or air conditioning in excess of that supplied by Landlord pursuant to Section 6.1 of this Lease, Tenant shall pay to Landlord, upon billing, the
cost of such excess consumption, the cost of the installation, operation, and maintenance of equipment which is installed in order to supply such excess consumption, and the cost of the increased wear and tear on existing equipment caused by such
excess consumption; and Landlord may install devices to separately meter any increased use and in such event Tenant shall pay the increased cost directly to Landlord, on demand, at the rates charged by the public utility company furnishing the same,
including the cost of such additional metering devices. Tenant’s use of electricity shall never exceed the capacity of the feeders to the Project or the risers or wiring installation. If Tenant desires to use heat, ventilation or air
conditioning during hours other than those for which Landlord is obligated to supply such utilities pursuant to the terms of Section 6.1 of this Lease, Tenant shall give Landlord such prior notice, if any, as Landlord shall from time to time
establish as appropriate, to the extent such additional utilities can be made available, and Landlord shall supply such utilities to Tenant at such hourly cost to Tenant (which shall be treated as Additional Rent and which may include an
administrative fee) as Landlord shall from time to time establish. 
  
 6.3 Interruption of Use. Tenant agrees that Landlord shall not be liable for damages, by abatement of Rent or otherwise, for failure to furnish or delay in furnishing any service (including telephone and telecommunication
services), or for any diminution in the quality or quantity thereof, when such failure or delay or diminution is occasioned, in whole or in part, by breakage, repairs, replacements, or improvements, by any strike, lockout or other labor trouble, by
inability to secure electricity, gas, water, or other fuel at the Building or Project after reasonable effort to do so, by any riot or other dangerous condition, emergency, accident or casualty whatsoever, by act or default of Tenant or other
parties, or by any other cause; and such failures or delays or diminution shall never be deemed to constitute an eviction or disturbance of Tenant’s use and possession of the Premises or relieve Tenant from paying Rent or performing any of its
obligations under this Lease. Furthermore, Landlord shall not be liable under any circumstances for a loss of, or injury to, property or for injury to, or interference with, Tenant’s business, including, without limitation, loss of profits,
however occurring, through or in connection with or incidental to a failure to furnish any of the services or utilities as set forth in this Article 6. Landlord may comply with voluntary controls or guidelines promulgated by any governmental entity
relating to the use or conservation of energy, water, gas, light or electricity or the reduction of automobile or other emissions without creating any liability of Landlord to Tenant under this Lease, provided that the Premises are not thereby
rendered untenantable. 
  
 6.4 Abatement of Rent. In
the event that Tenant is prevented from using, and does not use, the Premises or any portion thereof, as a result of any failure to provide services, utilities or access to the Premises as required by this Lease (an “Abatement
Event”), then Tenant shall give Landlord notice of such Abatement Event, and if such Abatement Event continues for five (5) consecutive business days after Landlord’s receipt of any such notice (the “Eligibility
Period”), then the Base Rent and Tenant’s Share of Direct Expenses 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 a 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; provided, however, in the
event that Tenant is prevented from using, and does not use, a portion of the Premises for a period of time in excess of the Eligibility Period and the remaining portion of the Premises is not sufficient to allow Tenant to effectively conduct its
business therein, and if Tenant does not conduct its business from such remaining portion, then for such time after expiration of the Eligibility Period during which Tenant is so prevented from effectively conducting its business therein, the Base
Rent and Tenant’s Share of Direct Expenses for the entire Premises shall be abated for such time as Tenant continues to be so prevented from using, and does not use, the 
  


					
	 	 	-12-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 Premises. If, however, Tenant reoccupies any portion of the Premises during such period, the Rent allocable to such
reoccupied portion, based on the proportion that the rentable area of such reoccupied portion of the Premises bears to the total rentable area of the Premises, shall be payable by Tenant from the date Tenant reoccupies such portion of the Premises.
Except as provided in this Section 6.4, nothing contained herein shall be interpreted to mean that Tenant is excused from paying Rent due hereunder. 
  
 ARTICLE 7 
  
 REPAIRS 
  
 Tenant shall, at Tenant’s own expense, pursuant to the terms of this Lease, including without limitation Article 8 hereof, keep the Premises, including all improvements, fixtures and furnishings therein, and the
floor or floors of the Building on which the Premises are located, in good order, repair and condition at all times during the Lease Term. In addition, Tenant shall, at Tenant’s own expense, but under the supervision and subject to the prior
approval of Landlord, and within any reasonable period of time specified by Landlord, pursuant to the terms of this Lease, including without limitation Article 8 hereof, promptly and adequately repair all damage to the Premises and replace or repair
all damaged, broken, or worn fixtures and appurtenances, except for damage caused by ordinary wear and tear or beyond the reasonable control of Tenant; provided however, that, at Landlord’s option, or if Tenant fails to commence such repairs
within ten (10) days following receipt of notice from Landlord, and diligently pursue such repair to completion, Landlord may, but need not, make such repairs and replacements, and Tenant shall pay Landlord the cost thereof, including a percentage
of the cost thereof (to be uniformly established for the Building and/or the Project) sufficient to reimburse Landlord for all overhead, general conditions, fees and other costs or expenses arising from Landlord’s involvement with such repairs
and replacements forthwith upon being billed for same. Subject to the terms of Article 27 of this Lease, Landlord may, but shall not be required to, enter the Premises at all reasonable times to make such repairs, alterations, improvements or
additions to the Premises or to the Project or to any equipment located in the Project as Landlord shall desire or deem necessary or as Landlord may be required to do by governmental or quasi-governmental authority or court order or decree. Tenant
hereby waives any and all rights under and benefits of subsection 1 of Section 1932 and Sections 1941 and 1942 of the California Civil Code or under any similar law, statute, or ordinance now or hereafter in effect. 
  
 ARTICLE 8 
  
 ADDITIONS AND ALTERATIONS 
  
 8.1 Landlord’s Consent to Alterations. Tenant may not make any improvements, alterations, additions or
changes to the Premises or any mechanical, plumbing or HVAC facilities or systems pertaining to the Premises (collectively, the “Alterations”) without first procuring the prior written consent of Landlord to such Alterations, which
consent shall be requested by Tenant not less than thirty (30) days prior to the commencement thereof, and which consent may be withheld in Landlord’s sole discretion. 
  
 8.2 Manner of Construction. Landlord may impose, as a condition of its consent to any and all Alterations or
repairs of the Premises or about the Premises, such commercially reasonable requirements as Landlord may deem desirable, including, but not limited to, the requirement that Tenant utilize for such purposes only contractors, subcontractors,
materials, mechanics and materialmen selected by Tenant from a list provided and approved by Landlord, the requirement that upon Landlord’s request, Tenant shall, at Tenant’s expense, remove such Alterations upon the expiration or any
early termination of the Lease Term. If such Alterations will involve the use of or disturb hazardous materials or substances existing in the Premises, Tenant shall comply with Landlord’s rules and regulations concerning such hazardous
materials or substances. Tenant shall construct such Alterations and perform such repairs in a good and workmanlike manner, in conformance with any and all applicable federal, state, county or municipal laws, rules and regulations and pursuant to,
if required by law, a valid building permit, issued by the City of San Francisco, all in conformance with Landlord’s construction rules and regulations. In the event Tenant performs any Alterations in the Premises which require or give rise to
governmentally required changes to the “Base Building,” as that term is defined below, then Landlord shall, at Tenant’s expense, make such changes to the Base Building. The “Base Building” shall include the structural
portions of the Building, and the public restrooms and the 
  


					
	 	 	-13-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 systems and equipment located in the internal core of the Building on the floor or floors on which the Premises are
located. In performing the work of any such Alterations, Tenant shall have the work performed in such manner so as not to obstruct access to the Project or any portion thereof, by any other tenant of the Project, and so as not to obstruct the
business of Landlord or other tenants in the Project. Tenant shall not use (and upon notice from Landlord shall cease using) contractors, services, workmen, labor, materials or equipment that, in Landlord’s reasonable judgment, would disturb
labor harmony with the workforce or trades engaged in performing other work, labor or services in or about the Building or the Common Areas. In addition to Tenant’s obligations under Article 9 of this Lease, upon completion of any Alterations,
Tenant agrees to cause a Notice of Completion to be recorded in the office of the Recorder of the County of San Francisco in accordance with Section 3093 of the Civil Code of the State of California or any successor statute, and Tenant shall deliver
to the Project management office a reproducible copy of the “as built” drawings of the Alterations as well as all permits, approvals and other documents issued by any governmental agency in connection with the Alterations. 
  
 8.3 Payment for Improvements. If payment is made directly to
contractors, Tenant shall comply with Landlord’s requirements for final lien releases and waivers in connection with Tenant’s payment for work to contractors. If Tenant orders any work directly from Landlord, Tenant shall pay to Landlord a
percentage of the cost of such work sufficient to compensate Landlord for all overhead, general conditions, fees and other costs and expenses arising from Landlord’s involvement with such work. If Tenant does not order the work directly from
Landlord, Tenant shall reimburse Landlord for Landlord’s reasonable, actual, out-of-pocket costs and expenses actually incurred in connection with Landlord’s review of such work. 
  
 8.4 Construction Insurance. In addition to the requirements of
Article 10 of this Lease, in the event that Tenant makes any Alterations, prior to the commencement of such Alterations, Tenant shall provide Landlord with evidence that Tenant carries “Builder’s All Risk” insurance in an amount
approved by Landlord covering the construction of such Alterations, and such other insurance as Landlord may require, it being understood and agreed that all of such Alterations shall be insured by Tenant pursuant to Article 10 of this Lease
immediately upon completion thereof. In addition, Landlord may, in its discretion, require Tenant to obtain a lien and completion bond or some alternate form of security satisfactory to Landlord in an amount sufficient to ensure the lien-free
completion of such Alterations and naming Landlord as a co-obligee. 
  
 8.5 Landlord’s Property. All Alterations, improvements, fixtures, equipment and/or appurtenances which may be installed or placed in or about the Premises, from time to time, shall be at the sole cost of Tenant and shall
be and become the property of Landlord, except that Tenant may remove any Alterations, improvements, fixtures and/or equipment which Tenant can substantiate to Landlord have not been paid for with any Tenant improvement allowance funds provided to
Tenant by Landlord, provided Tenant repairs any damage to the Premises and Building caused by such removal and returns the affected portion of the Premises to a building standard tenant improved condition as determined by Landlord. Furthermore,
Landlord may, by written notice to Tenant not less than sixty (60) days prior to the end of the Lease Term, or given following any earlier termination of this Lease, require Tenant, at Tenant’s expense, to remove any Alterations or improvements
in the Premises, and to repair any damage to the Premises and Building caused by such removal and return the affected portion of the Premises to a building standard tenant improved condition as determined by Landlord. If Tenant fails to complete
such removal and/or to repair any damage caused by the removal of any Alterations or improvements in the Premises, and return the affected portion of the Premises to a building standard tenant improved condition as determined by Landlord, Landlord
may do so and may charge the cost thereof to Tenant. Tenant hereby protects, defends, indemnifies and holds Landlord harmless from any liability, cost, obligation, expense or claim of lien in any manner relating to the installation, placement,
removal or financing of any such Alterations, improvements, fixtures and/or equipment in, on or about the Premises, which obligations of Tenant shall survive the expiration or earlier termination of this Lease. 
  
 8.6 Improvement Allowance. Tenant shall be entitled to an
allowance for the design and construction of improvements in the Premises (the “Improvements”) in an amount equal to Ten Thousand Eight Hundred Seventy-Five and No/100 Dollars ($10,875.00) (i.e. $2.50 per rentable square foot of the
Premises) (the “Improvement Allowance”), which Improvement Allowance may be utilized by Tenant for the costs of the Improvements at any time through and 
  


					
	 	 	-14-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 including March 31, 2006. Any portion of the Improvement Allowance which has not been spent as of April 1, 2006 shall
revert to Landlord and Tenant shall have no further rights thereto. Any costs incurred by Tenant in connection with Tenant’s construction of the Improvements which are in excess of the Improvement Allowance shall be paid for by Tenant. The
Improvement Allowance shall be disbursed by Landlord pursuant to Landlord’s reasonable disbursement process (which shall include, without limitation, the requirement that Tenant provide invoices and mechanics’ lien releases acceptable to
Landlord) for costs related to the construction of the Improvements. Tenant shall not be charged a supervision fee in connection with Tenant’s construction of the Improvements; provided, however, that Tenant shall reimburse Landlord within
thirty (30) days of Tenant’s receipt of an invoice for any out-of-pocket costs actually incurred by Landlord in connection with Tenant’s construction of the Improvements. 
  
 ARTICLE 9 
  
 COVENANT AGAINST LIENS 
  
 Tenant shall keep the Project and Premises free from any liens or encumbrances arising out of the work performed, materials furnished or obligations
incurred by or on behalf of Tenant, and shall protect, defend, indemnify and hold Landlord harmless from and against any claims, liabilities, judgments or costs (including, without limitation, reasonable attorneys’ fees and costs) arising out
of same or in connection therewith. Tenant shall give Landlord notice at least twenty (20) days prior to the commencement of any such work on the Premises (or such additional time as may be necessary under applicable laws) to afford Landlord the
opportunity of posting and recording appropriate notices of non-responsibility. Tenant shall remove any such lien or encumbrance by bond or otherwise within five (5) days after notice by Landlord, and if Tenant shall fail to do so, Landlord may pay
the amount necessary to remove such lien or encumbrance, without being responsible for investigating the validity thereof. The amount so paid shall be deemed Additional Rent under this Lease payable upon demand, without limitation as to other
remedies available to Landlord under this Lease. Nothing contained in this Lease shall authorize Tenant to do any act which shall subject Landlord’s title to the Building or Premises to any liens or encumbrances whether claimed by operation of
law or express or implied contract. Any claim to a lien or encumbrance upon the Building or Premises arising in connection with any such work or respecting the Premises not performed by or at the request of Landlord shall be null and void, or at
Landlord’s option shall attach only against Tenant’s interest in the Premises and shall in all respects be subordinate to Landlord’s title to the Project, Building and Premises. 
  
 ARTICLE 10 
  
 INSURANCE 
  
 10.1 Indemnification and Waiver. Except to the extent caused by
the negligence or willful misconduct of the “Landlord Parties,” as that term is defined below, Tenant hereby assumes all risk of damage to property or injury to persons in, upon or about the Premises from any cause whatsoever and agrees
that Landlord, its partners, subpartners and their respective officers, agents, servants, employees, and independent contractors (collectively, “Landlord Parties”) shall not be liable for, and are hereby released from any
responsibility for, any damage either to person or property or resulting from the loss of use thereof, which damage is sustained by Tenant or by other persons claiming through Tenant. Tenant shall indemnify, defend, protect, and hold harmless the
Landlord Parties from any and all loss, cost, damage, expense and liability (including without limitation court costs and reasonable attorneys’ fees) incurred in connection with or arising from any cause in, on or about the Premises, any acts,
omissions or negligence of Tenant or of any person claiming by, through or under Tenant, or of the contractors, agents, servants, employees, invitees, guests or licensees of Tenant or any such person, in, on or about the Project or any breach of the
terms of this Lease, either prior to, during, or after the expiration of the Lease Term, provided that the terms of the foregoing indemnity shall not apply to the negligence or willful misconduct of Landlord or the Landlord Parties. Should Landlord
be named as a defendant in any suit brought against Tenant in connection with or arising out of Tenant’s occupancy of the Premises, then except to the extent caused by the negligence or willful misconduct of Landlord or the Landlord Parties,
Tenant shall pay to Landlord its costs and expenses incurred in such suit, including without limitation, its actual professional fees such as appraisers’, accountants’ and attorneys’ fees. Further, Tenant’s agreement to indemnify
Landlord pursuant to this Section 10.1 is not intended and shall not relieve any insurance carrier of its obligations under policies required to be carried by Tenant pursuant to the provisions of this 
  


					
	 	 	-15-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 Lease, to the extent such policies cover the matters subject to Tenant’s indemnification obligations; nor shall they
supersede any inconsistent agreement of the parties set forth in any other provision of this Lease. The provisions of this Section 10.1 shall survive the expiration or sooner termination of this Lease with respect to any claims or liability arising
in connection with any event occurring prior to such expiration or termination. 
  
 10.2 Tenant’s Compliance With Landlord’s Fire and Casualty Insurance. Tenant shall, at Tenant’s expense, comply with all commercially reasonable insurance company requirements pertaining
to the use of the Premises. If Tenant’s conduct or use of the Premises causes any increase in the premium for such insurance policies then Tenant shall reimburse Landlord for any such increase. Tenant, at Tenant’s expense, shall comply
with all rules, orders, regulations or requirements of the American Insurance Association (formerly the National Board of Fire Underwriters) and with any similar body. 
  
 10.3 Tenant’s Insurance. Tenant shall maintain the following coverages in the following amounts.

  
 10.3.1 Commercial General Liability Insurance covering the
insured against claims of bodily injury, personal injury and property damage (including loss of use thereof) arising out of Tenant’s operations, and contractual liabilities (covering the performance by Tenant of its indemnity agreements)
including a Broad Form endorsement covering the insuring provisions of this Lease and the performance by Tenant of the indemnity agreements set forth in Section 10.1 of this Lease, for limits of liability not less than: 
  

			
	 Bodily Injury and
	  	$3,000,000 each occurrence
	 Property Damage Liability
	  	$3,000,000 annual aggregate
		
	 Personal Injury Liability
	  	$3,000,000 each occurrence
	 	  	$3,000,000 annual aggregate
	 	  	0% Insured’s participation

  
 10.3.2 Physical Damage
Insurance covering (i) all office furniture, business and trade fixtures, office equipment, free-standing cabinet work, movable partitions, merchandise and all other items of Tenant’s property on the Premises installed by, for, or at the
expense of Tenant, (ii) any improvements which exist in the Premises as of the Lease Commencement Date (excluding the Base Building) and (iii) all other improvements, alterations and additions to the Premises (collectively, items (ii) and (iii), the
“Tenant Improvements”). Such insurance shall be written on an “all risks” of physical loss or damage basis, for the full replacement cost value (subject to reasonable deductible amounts) new without deduction for
depreciation of the covered items and in amounts that meet any co-insurance clauses of the policies of insurance and shall include coverage for damage or other loss caused by fire or other peril including, but not limited to, vandalism and malicious
mischief, theft, water damage of any type, including sprinkler leakage, bursting or stoppage of pipes, and explosion, and providing business interruption coverage for a period of one year. 
  
 10.3.3 Worker’s Compensation and Employer’s Liability or other
similar insurance pursuant to all applicable state and local statutes and regulations. 
  
 10.3.4 Business Interruption Insurance in the amount necessary to insure payment of Tenant’s obligations to pay Rent hereunder for a period of not less than twelve (12) months. 
  
 10.4 Form of Policies. The minimum limits of policies of
insurance required of Tenant under this Lease shall in no event limit the liability of Tenant under this Lease. Such insurance shall (i) name Landlord, and any other party the Landlord so specifies, as an additional insured, including
Landlord’s managing agent, if any; (ii) specifically cover the liability assumed by Tenant under this Lease, including, but not limited to, Tenant’s obligations under Section 10.1 of this Lease; (iii) be issued by an insurance company
having a rating of not less than A-X in Best’s Insurance Guide or which is otherwise acceptable to Landlord and licensed to do business in the State of California; (iv) be primary insurance as to all claims thereunder and provide that any
insurance carried by Landlord is excess and is non-contributing with any insurance requirement of Tenant; (v) be in form and content reasonably acceptable to Landlord; and (vi) provide that said insurance shall not be canceled or coverage changed
unless thirty (30) days’ 
  


					
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 prior written notice shall have been given to Landlord and any mortgagee of Landlord. Tenant shall deliver said policy or
policies or certificates (including endorsements) thereof to Landlord on or before the Lease Commencement Date and at least thirty (30) days before the expiration dates thereof. In the event Tenant shall fail to procure such insurance, or to deliver
such policies or certificate within ten (10) days following receipt of notice from Landlord, Landlord may, at its option, procure such policies for the account of Tenant, and the cost thereof shall be paid to Landlord within five (5) days after
delivery to Tenant of bills therefor. 
  
 10.5
Subrogation. Landlord and Tenant intend that their respective property loss risks shall be borne by reasonable insurance carriers to the extent above provided, and Landlord and Tenant hereby agree to look solely to, and seek recovery
only from, their respective insurance carriers in the event of a property loss to the extent that such coverage is agreed to be provided hereunder. The parties each hereby waive all rights and claims against each other for such losses, and waive all
rights of subrogation of their respective insurers, provided such waiver of subrogation shall not affect the right to the insured to recover thereunder. The parties agree that their respective insurance policies are now, or shall be, endorsed such
that the waiver of subrogation shall not affect the right of the insured to recover thereunder, so long as no material additional premium is charged therefor. 
  

10.6 Additional Insurance Obligations. Tenant shall carry and maintain during the entire Lease Term, as the same may be extended, at
Tenant’s sole cost and expense, increased amounts of the insurance required to be carried by Tenant pursuant to this Article 10 and such other reasonable types of insurance coverage and in such reasonable amounts covering the Premises and
Tenant’s operations therein, as may be reasonably requested by Landlord, but in no event shall such increased amounts of insurance or such other reasonable types of insurance coverage be in excess of that being required by landlords of
comparable buildings located in the vicinity of the Building. 
  
 ARTICLE 11 
  
 DAMAGE AND DESTRUCTION

  
 11.1 Repair of Damage to Premises by
Landlord. Tenant shall promptly notify Landlord of any damage to the Premises resulting from fire or any other casualty. If the Premises or any Common Areas serving or providing access to the Premises shall be damaged by fire or other
casualty, Landlord shall promptly and diligently, subject to reasonable delays for insurance adjustment or other matters beyond Landlord’s reasonable control, and subject to all other terms of this Article 11, restore the Base Building and such
Common Areas. Such restoration shall be to substantially the same condition of the Base Building and the Common Areas prior to the casualty, except for modifications required by zoning and building codes and other laws or by the holder of a mortgage
on the Building or Project or any other modifications to the Common Areas deemed desirable by Landlord, provided that use of and access to the Premises and any common restrooms serving the Premises shall not be materially impaired. Upon the
occurrence of any damage to the Premises, upon notice (the “Landlord Repair Notice”) to Tenant from Landlord, Tenant shall assign to Landlord (or to any party designated by Landlord) all insurance proceeds payable to Tenant under
Tenant’s insurance required under Section 10.3.2 (ii) and (iii) of this Lease, and Landlord shall repair any injury or damage to the Tenant Improvements installed in the Premises and shall return such Tenant Improvements to their original
condition; provided that if the cost of such repair by Landlord exceeds the amount of insurance proceeds received by Landlord from Tenant’s insurance carrier, as assigned by Tenant, the cost of such repairs shall be paid by Tenant to Landlord
prior to Landlord’s commencement of repair of the damage, or as soon as such additional costs are known. In the event that Landlord does not deliver the Landlord Repair Notice within sixty (60) days following the date the casualty becomes known
to Landlord, Tenant shall, at its sole cost and expense, repair any injury or damage to the Tenant Improvements installed in the Premises and shall return such Tenant Improvements to their original condition. Whether or not Landlord delivers a
Landlord Repair Notice, prior to the commencement of construction, Tenant shall submit to Landlord, for Landlord’s review and approval, all plans, specifications and working drawings relating thereto, and Landlord shall select the contractors
to perform such improvement work. Landlord shall not be liable for any inconvenience or annoyance to Tenant or its visitors, or injury to Tenant’s business resulting in any way from such damage or the repair thereof; provided however, that if
such fire or other casualty shall have damaged the Premises or Common Areas necessary to Tenant’s access to and occupancy of the Premises, Landlord shall allow Tenant a 
  


					
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 proportionate abatement of Rent, during the time and to the extent the Premises are unfit for occupancy for the purposes
permitted under this Lease, and not occupied by Tenant as a result thereof; provided, further, however, that if the damage or destruction is due to the negligence or wilful misconduct of Tenant or any of its agents, employees, contractors, invitees
or guests, Tenant shall be responsible for any reasonable, applicable insurance deductible (which shall be payable to Landlord upon demand) and there shall be no rent abatement. In the event that Landlord shall not deliver the Landlord Repair
Notice, Tenant’s right to rent abatement pursuant to the preceding sentence shall terminate as of the date which is reasonably determined by Landlord to be the date Tenant should have completed repairs to the Premises assuming Tenant used
reasonable due diligence in connection therewith. 
  
 11.2
Landlord’s Option to Repair. Notwithstanding the terms of Section 11.1 of this Lease, Landlord may elect not to rebuild and/or restore the Premises, Building and/or Project, and instead terminate this Lease, by notifying Tenant in
writing of such termination within sixty (60) days after the date of damage, such notice to include a termination date giving Tenant sixty (60) days to vacate the Premises, but Landlord may so elect only if the Building or Project shall be damaged
by fire or other casualty or cause, whether or not the Premises are affected, and one or more of the following conditions is present: (i) in Landlord’s reasonable judgment, repairs cannot reasonably be completed within ninety (90) days after
the date of discovery of the damage (when such repairs are made without the payment of overtime or other premiums); (ii) the holder of any mortgage on the Building or Project or ground lessor with respect to the Building or Project shall require
that the insurance proceeds or any portion thereof be used to retire the mortgage debt, or shall terminate the ground lease, as the case may be; (iii) the damage is not fully covered by Landlord’s insurance policies; or (iv) Landlord decides to
rebuild the Building or Common Areas so that they will be substantially different structurally or architecturally; (v) the damage occurs during the last eighteen (18) months of the Lease Term; or (vi) any owner of any other portion of the Project,
other than Landlord, does not intend to repair the damage to such portion of the Project; provided, however, that if Landlord does not elect to terminate this Lease pursuant to Landlord’s termination right as provided above, and the repairs
cannot, in the reasonable opinion of Landlord, be completed within one hundred eighty (180) days after being commenced, or the damage occurs during the last twelve (12) months of the Lease Term, Tenant may elect, no earlier than sixty (60) days
after the date of the damage and not later than ninety (90) days after the date of such damage, to terminate this Lease by written notice to Landlord effective as of the date specified in the notice, which date shall not be less than thirty (30)
days nor more than sixty (60) days after the date such notice is given by Tenant. 
  
 11.3 Waiver of Statutory Provisions. The provisions of this Lease, including this Article 11, 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, the Building or the Project, and any statute or regulation of the State of California, including, without limitation, Sections 1932(2) and 1933(4) of the California Civil Code, with respect to any
rights or obligations concerning damage or destruction in the absence of an express agreement between the parties, and any other statute or regulation, now or hereafter in effect, shall have no application to this Lease or any damage or destruction
to all or any part of the Premises, the Building or the Project. 
  
 ARTICLE 12 
  
 NONWAIVER 

 
 No provision of this Lease shall be deemed waived by either party hereto
unless expressly waived in a writing signed thereby. The waiver by either party hereto of any breach of any term, covenant or condition herein contained shall not be deemed to be a waiver of any subsequent breach of same or any other term, covenant
or condition herein contained. The subsequent acceptance of Rent hereunder by Landlord shall not be deemed to be a waiver of any preceding breach by Tenant of any term, covenant or condition of this Lease, other than the failure of Tenant to pay the
particular Rent so accepted, regardless of Landlord’s knowledge of such preceding breach at the time of acceptance of such Rent. No acceptance of a lesser amount than the Rent herein stipulated shall be deemed a waiver of Landlord’s right
to receive the full amount due, nor shall any endorsement or statement on any check or payment or any letter accompanying such check or payment be deemed an accord and satisfaction, and Landlord may accept such check or payment without prejudice to
Landlord’s right to recover the full amount due. No receipt of monies by Landlord from Tenant after the termination of this Lease shall in any way alter the length of the Lease Term or of Tenant’s right of possession hereunder, or after

  


					
	 	 	-18-	 	 CHINA BASIN LANDING
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 the giving of any notice shall reinstate, continue or extend the Lease Term or affect any notice given Tenant prior to
the receipt of such monies, it being agreed that after the service of notice or the commencement of a suit, or after final judgment for possession of the Premises, Landlord may receive and collect any Rent due, and the payment of said Rent shall not
waive or affect said notice, suit or judgment. 
  
 ARTICLE 13

  
 CONDEMNATION 
  
 If the whole or any part of the Premises, Building or Project shall be taken
by power of eminent domain or condemned by any competent authority for any public or quasi-public use or purpose, or if any adjacent property or street shall be so taken or condemned, or reconfigured or vacated by such authority in such manner as to
require the use, reconstruction or remodeling of any part of the Premises, Building or Project, or if Landlord shall grant a deed or other instrument in lieu of such taking by eminent domain or condemnation, Landlord shall have the option to
terminate this Lease effective as of the date possession is required to be surrendered to the authority. If more than twenty-five percent (25%) of the rentable square feet of the Premises is taken, or if access to the Premises is substantially
impaired, in each case for a period in excess of ninety (90) days, Tenant shall have the option to terminate this Lease effective as of the date possession is required to be surrendered to the authority. Tenant shall not because of such taking
assert any claim against Landlord or the authority for any compensation because of such taking and Landlord shall be entitled to the entire award or payment in connection therewith, except that Tenant shall have the right to file any separate claim
available to Tenant for any taking of Tenant’s personal property and fixtures belonging to Tenant and removable by Tenant upon expiration of the Lease Term pursuant to the terms of this Lease, and for moving expenses, so long as such claims do
not diminish the award available to Landlord, its ground lessor with respect to the Building or Project or its mortgagee, and such claim is payable separately to Tenant. All Rent shall be apportioned as of the date of such termination. If any part
of the Premises shall be taken, and this Lease shall not be so terminated, the Rent shall be proportionately abated. Tenant hereby waives any and all rights it might otherwise have pursuant to Section 1265.130 of The California Code of Civil
Procedure. Notwithstanding anything to the contrary contained in this Article 13, in the event of a temporary taking of all or any portion of the Premises for a period of ninety (90) days or less, then this Lease shall not terminate but the Base
Rent and the Additional Rent shall be abated for the period of such taking in proportion to the ratio that the amount of rentable square feet of the Premises taken bears to the total rentable square feet of the Premises. Landlord shall be entitled
to receive the entire award made in connection with any such temporary taking. 
  
 ARTICLE 14 
  
 ASSIGNMENT AND SUBLETTING 
  
 14.1
Transfers. Tenant shall not, without the prior written consent of Landlord, assign, mortgage, pledge, hypothecate, encumber, or permit any lien to attach to, or otherwise transfer, this Lease or any interest hereunder, permit any
assignment, or other transfer of this Lease or any interest hereunder by operation of law, sublet the Premises or any part thereof, or enter into any license or concession agreements or otherwise permit the occupancy or use of the Premises or any
part thereof by any persons other than Tenant and its employees and contractors (all of the foregoing are hereinafter sometimes referred to collectively as “Transfers” and any person to whom any Transfer is made or sought to be made
is hereinafter sometimes referred to as a “Transferee”). If Tenant desires Landlord’s consent to any Transfer, Tenant shall notify Landlord in writing, which notice (the “Transfer Notice”) shall include (i) the
proposed effective date of the Transfer, which shall not be less than thirty (30) days nor more than one hundred eighty (180) days after the date of delivery of the Transfer Notice, (ii) a description of the portion of the Premises to be transferred
(the “Subject Space”), (iii) all of the terms of the proposed Transfer and the consideration therefor, including calculation of the “Transfer Premium”, as that term is defined in Section 14.3 below, in connection with such
Transfer, the name and address of the proposed Transferee, and a copy of all existing executed and/or proposed documentation pertaining to the proposed Transfer, including all existing operative documents to be executed to evidence such Transfer or
the agreements incidental or related to such Transfer, provided that Landlord shall have the right to require Tenant to utilize Landlord’s standard Transfer documents in connection with the documentation of such Transfer, (iv) current

  


					
	 	 	-19-	 	 CHINA BASIN LANDING
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 financial statements of the proposed Transferee certified by an officer, partner or owner thereof, business credit and
personal references and history of the proposed Transferee and any other information required by Landlord which will enable Landlord to determine the financial responsibility, character, and reputation of the proposed Transferee, nature of such
Transferee’s business and proposed use of the Subject Space, and (v) an executed estoppel certificate from Tenant in the form attached hereto as Exhibit E. Any Transfer made without Landlord’s prior written consent shall, at
Landlord’s option, be null, void and of no effect, and shall, at Landlord’s option, constitute a default by Tenant under this Lease. Whether or not Landlord consents to any proposed Transfer, Tenant shall pay Landlord’s review and
processing fees, as well as any reasonable professional fees (including, without limitation, attorneys’, accountants’, architects’, engineers’ and consultants’ fees) incurred by Landlord, within thirty (30) days after
written request by Landlord. 
  
 14.2 Landlord’s
Consent. Landlord shall not unreasonably withhold its consent to any proposed Transfer of the Subject Space to the Transferee on the terms specified in the Transfer Notice. Without limitation as to other reasonable grounds for withholding
consent, the parties hereby agree that it shall be reasonable under this Lease and under any applicable law for Landlord to withhold consent to any proposed Transfer where one or more of the following apply: 
  
 14.2.1 The Transferee is of a character or reputation or engaged in a
business which is not consistent with the quality of the Building or the Project, or would be a significantly less prestigious occupant of the Building than Tenant; 
  
 14.2.2 The Transferee intends to use the Subject Space for purposes which are not permitted under this Lease; 
  
 14.2.3 The Transferee is either a governmental agency or instrumentality
thereof; 
  
 14.2.4 Intentionally Deleted; 
  
 14.2.5 The Transferee is not a party of reasonable financial worth and/or
financial stability in light of the responsibilities to be undertaken in connection with the Transfer on the date consent is requested; 
  
 14.2.6 The proposed Transfer would cause a violation of another lease for space in the Project, or would give an occupant of the Project a right to cancel
its lease; 
  
 14.2.7 The terms of the proposed Transfer will
allow the Transferee to exercise a right of renewal, right of expansion, right of first offer, or other similar right held by Tenant (or will allow the Transferee to occupy space leased by Tenant pursuant to any such right); or 
  
 14.2.8 Either the proposed Transferee, or any person or entity which directly
or indirectly, controls, is controlled by, or is under common control with, the proposed Transferee, (i) occupies space in the Project at the time of the request for consent, or (ii) is negotiating or has negotiated with Landlord to lease space in
the Project. 
  
 14.2.9 The Transferee does not intend to occupy
the entire Premises and conduct its business therefrom for a substantial portion of the term of the Transfer. 
  
 If Landlord consents to any Transfer pursuant to the terms of this Section 14.2 (and does not exercise any recapture rights Landlord may have under
Section 14.4 of this Lease), Tenant may within six (6) months after Landlord’s consent, but not later than the expiration of said six-month period, enter into such Transfer of the Premises or portion thereof, upon substantially the same terms
and conditions as are set forth in the Transfer Notice furnished by Tenant to Landlord pursuant to Section 14.1 of this Lease, provided that if there are any changes in the terms and conditions from those specified in the Transfer Notice (i) such
that Landlord would initially have been entitled to refuse its consent to such Transfer under this Section 14.2, or (ii) which would cause the proposed Transfer to be more favorable to the Transferee than the terms set forth in Tenant’s
original Transfer Notice, Tenant shall again submit the Transfer to Landlord for its approval and other action under this Article 14 (including Landlord’s right of recapture, if any, under Section 14.4 of this Lease). Notwithstanding anything
to the contrary in this Lease, if Tenant or any proposed Transferee claims that Landlord has unreasonably withheld or delayed 
  


					
	 	 	-20-	 	 CHINA BASIN LANDING
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 its consent under Section 14.2 or otherwise has breached or acted unreasonably under this Article 14, their sole remedies
shall be a declaratory judgment and an injunction for the relief sought without any monetary damages, and Tenant hereby waives all other remedies, including, without limitation, any right at law or equity to terminate this Lease, on its own behalf
and, to the extent permitted under all applicable laws, on behalf of the proposed Transferee. Tenant shall indemnify, defend and hold harmless Landlord from any and all liability, losses, claims, damages, costs, expenses, causes of action and
proceedings involving any third party or parties (including without limitation Tenant’s proposed subtenant or assignee) who claim they were damaged by Landlord’s wrongful withholding or conditioning of Landlord’s consent. 

 
 14.3 Transfer Premium. If Landlord consents to a Transfer,
as a condition thereto which the parties hereby agree is reasonable, Tenant shall pay to Landlord fifty percent (50%) of any “Transfer Premium,” as that term is defined in this Section 14.3, received by Tenant from such Transferee, after
deducting the reasonable expenses incurred by Tenant for (i) any changes, alterations and improvements to the Premises in connection with the Transfer, (ii) any commercially reasonable brokerage commissions in connection with the Transfer, (iii)
reasonable legal fees in connection with the Transfer, and (iv) reasonable out-of-pocket costs of advertising the Subject Space related to the Transfer. “Transfer Premium” shall mean all rent, additional rent or other consideration
payable by such Transferee in connection with the Transfer in excess of the Rent and Additional Rent payable by Tenant under this Lease during the term of the Transfer on a per rentable square foot basis if less than all of the Premises is
transferred. “Transfer Premium” shall also include, but not be limited to, key money, bonus money or other cash consideration paid by Transferee to Tenant in connection with such Transfer, and any payment in excess of fair market value for
services rendered by Tenant to Transferee or for assets, fixtures, inventory, equipment, or furniture transferred by Tenant to Transferee in connection with such Transfer. 
  
 14.4 Landlord’s Option as to Subject Space. Notwithstanding anything to the contrary contained in this
Article 14, Landlord shall have the option, by giving written notice to Tenant within thirty (30) days after receipt of any Transfer Notice, to recapture the Subject Space. Such recapture notice shall cancel and terminate this Lease with respect to
the Subject Space as of the date stated in the Transfer Notice as the effective date of the proposed Transfer until the last day of the term of the Transfer as set forth in the Transfer Notice (or at Landlord’s option, shall cause the Transfer
to be made to Landlord or its agent, in which case the parties shall execute the Transfer documentation promptly thereafter). In the event of a recapture by Landlord, if this Lease shall be canceled with respect to less than the entire Premises, the
Rent reserved herein shall be prorated on the basis of the number of rentable square feet retained by Tenant in proportion to the number of rentable square feet contained in the Premises, and this Lease as so amended shall continue thereafter in
full force and effect, and upon request of either party, the parties shall execute written confirmation of the same. If Landlord declines, or fails to elect in a timely manner to recapture the Subject Space under this Section 14.4, then, provided
Landlord has consented to the proposed Transfer, Tenant shall be entitled to proceed to transfer the Subject Space to the proposed Transferee, subject to provisions of this Article 14. 
  
 14.5 Effect of Transfer. If Landlord consents to a Transfer, (i) the terms and conditions of this Lease shall
in no way be deemed to have been waived or modified, (ii) such consent shall not be deemed consent to any further Transfer by either Tenant or a Transferee, (iii) Tenant shall deliver to Landlord, promptly after execution, an original executed copy
of all documentation pertaining to the Transfer in form reasonably acceptable to Landlord, (iv) Tenant shall furnish upon Landlord’s request a complete statement, certified by an independent certified public accountant, or Tenant’s chief
financial officer, setting forth in detail the computation of any Transfer Premium Tenant has derived and shall derive from such Transfer, and (v) no Transfer relating to this Lease or agreement entered into with respect thereto, whether with or
without Landlord’s consent, shall relieve Tenant or any guarantor of the Lease from any liability under this Lease, including, without limitation, in connection with the Subject Space. Landlord or its authorized representatives shall have the
right at all reasonable times to audit the books, records and papers of Tenant relating to any Transfer, and shall have the right to make copies thereof. If the Transfer Premium respecting any Transfer shall be found understated, Tenant shall,
within thirty (30) days after demand, pay the deficiency, and if understated by more than two percent (2%), Tenant shall pay Landlord’s costs of such audit. 
  
 14.6 Additional Transfers. For purposes of this Lease, the term “Transfer” shall also include
(i) if Tenant is a partnership, the withdrawal or change, voluntary, involuntary or by 
  


					
	 	 	-21-	 	 CHINA BASIN LANDING
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 operation of law, of fifty percent (50%) or more of the partners, or transfer of fifty percent (50%) or more of
partnership interests, within a twelve (12)-month period, or the dissolution of the partnership without immediate reconstitution thereof, and (ii) if Tenant is a closely held corporation (i.e., whose stock is not publicly held and not traded through
an exchange or over the counter), (A) the dissolution, merger, consolidation or other reorganization of Tenant or (B) the sale or other transfer of an aggregate of fifty percent (50%) or more of the voting shares of Tenant (other than to immediate
family members by reason of gift or death), within a twelve (12)-month period, or (C) the sale, mortgage, hypothecation or pledge of an aggregate of fifty percent (50%) or more of the value of the unencumbered assets of Tenant within a twelve
(12)-month period. 
  
 14.7 Occurrence of Default.
Any Transfer hereunder shall be subordinate and subject to the provisions of this Lease, and if this Lease shall be terminated during the term of any Transfer, Landlord shall have the right to: (i) treat such Transfer as cancelled and repossess the
Subject Space by any lawful means, or (ii) require that such Transferee attorn to and recognize Landlord as its landlord under any such Transfer. If Tenant shall be in default under this Lease, Landlord is hereby irrevocably authorized, as
Tenant’s agent and attorney-in-fact, to direct any Transferee to make all payments under or in connection with the Transfer directly to Landlord (which Landlord shall apply towards Tenant’s obligations under this Lease) until such default
is cured. Such Transferee shall rely on any representation by Landlord that Tenant is in default hereunder, without any need for confirmation thereof by Tenant. Upon any assignment, the assignee shall assume in writing all obligations and covenants
of Tenant thereafter to be performed or observed under this Lease. No collection or acceptance of rent by Landlord from any Transferee shall be deemed a waiver of any provision of this Article 14 or the approval of any Transferee or a release of
Tenant from any obligation under this Lease, whether theretofore or thereafter accruing. In no event shall Landlord’s enforcement of any provision of this Lease against any Transferee be deemed a waiver of Landlord’s right to enforce any
term of this Lease against Tenant or any other person. If Tenant’s obligations hereunder have been guaranteed, Landlord’s consent to any Transfer shall not be effective unless the guarantor also consents to such Transfer. 
  
 ARTICLE 15 
  
 SURRENDER OF PREMISES; OWNERSHIP AND 
 REMOVAL OF TRADE FIXTURES 
  
 15.1 Surrender of Premises. No act or thing done by Landlord or any agent or employee of Landlord during the Lease Term shall be deemed to
constitute an acceptance by Landlord of a surrender of the Premises unless such intent is specifically acknowledged in writing by Landlord. The delivery of keys to the Premises to Landlord or any agent or employee of Landlord shall not constitute a
surrender of the Premises or effect a termination of this Lease, whether or not the keys are thereafter retained by Landlord, and notwithstanding such delivery Tenant shall be entitled to the return of such keys at any reasonable time upon request
until this Lease shall have been properly terminated. The voluntary or other surrender of this Lease by Tenant, whether accepted by Landlord or not, or a mutual termination hereof, shall not work a merger, and at the option of Landlord shall operate
as an assignment to Landlord of all subleases or subtenancies affecting the Premises or terminate any or all such sublessees or subtenancies. 
  
 15.2 Removal of Tenant Property by Tenant. Upon the expiration of the Lease Term, or upon any earlier termination of this Lease, Tenant
shall, subject to the provisions of this Article 15, quit and surrender possession of the Premises to Landlord in as good order and condition as when Tenant took possession and as thereafter improved by Landlord and/or Tenant, reasonable wear and
tear and repairs which are specifically made the responsibility of Landlord hereunder excepted. Upon such expiration or termination, Tenant shall, without expense to Landlord, remove or cause to be removed from the Premises all debris and rubbish,
and such items of furniture, equipment, business and trade fixtures, free-standing cabinet work, movable partitions and other articles of personal property owned by Tenant or installed or placed by Tenant at its expense in the Premises, and such
similar articles of any other persons claiming under Tenant, as Landlord may, in its sole discretion, require to be removed (the “Tenant Personal Property”), and Tenant shall repair at its own expense all damage to the Premises and
Building resulting from such removal. Landlord shall have the right, at Tenant’s sole cost and expense, to dispose of any Tenant Personal Property remaining in the Premises after Tenant’s vacation of the same in any manner Landlord sees
fit. 
  


					
	 	 	-22-	 	 CHINA BASIN LANDING
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 ARTICLE 16 
  

HOLDING OVER 
  
 If Tenant holds over after the expiration of the Lease Term or earlier termination thereof, with or without the express or implied consent of Landlord,
such tenancy shall be from month-to-month only, and shall not constitute a renewal hereof or an extension for any further term, and in such case Rent shall be payable at a monthly rate equal to the product of (i) the Rent applicable during the last
rental period of the Lease Term under this Lease, and (ii) a percentage equal to the sum of (A) 200% and (B) the percentage by which Rent was increased at the time of the last increase of Rent during the Lease Term. Such month-to-month tenancy shall
be subject to every other applicable term, covenant and agreement contained herein. Nothing contained in this Article 16 shall be construed as consent by Landlord to any holding over by Tenant, and Landlord expressly reserves the right to require
Tenant to surrender possession of the Premises to Landlord as provided in this Lease upon the expiration or other termination of this Lease. The provisions of this Article 16 shall not be deemed to limit or constitute a waiver of any other rights or
remedies of Landlord provided herein or at law. If Tenant fails to surrender the Premises upon the termination or expiration of this Lease, in addition to any other liabilities to Landlord accruing therefrom, Tenant shall protect, defend, indemnify
and hold Landlord harmless from all loss, costs (including reasonable attorneys’ fees) and liability resulting from such failure, including, without limiting the generality of the foregoing, any claims made by any succeeding tenant founded upon
such failure to surrender and any lost profits to Landlord resulting therefrom. 
  
 ARTICLE 17 
  
 ESTOPPEL CERTIFICATES 
  
 Within ten (10)
business days following a request in writing by Landlord or Tenant, Tenant or Landlord, as the case may be, shall execute, acknowledge and deliver to the requesting party (the “Requesting Party“), an estoppel certificate, which, as
submitted by the Requesting Party, shall be substantially in the reasonable form of Exhibit E, attached hereto (or such other commercially reasonable form as may be required by any prospective mortgagee or purchaser of the Project, or
any portion thereof, or any assignee or sublessee), indicating therein any exceptions thereto that may exist at that time, and shall also contain any other information reasonably requested by the Requesting Party or Landlord’s mortgagee, as the
case may be. Neither party shall make such a request more than two (2) times in any twelve (12) month period (unless required more often as a result of a pending bona fide sale or financing of the Project, or a Tenant financing). The appropriate
modification shall be made to Exhibit E when Tenant is the Requesting Party. Any such certificate may be relied upon by any prospective mortgagee or purchaser of all or any portion of the Project. At any time during the Lease Term, but
no more than two times in any twelve (12) month period (unless required more often as a result of a pending bona fide sale or financing of the Project or Building), Landlord may require Tenant to provide Landlord with the most recent financial
statements of Tenant and financial statements of Tenant for the two (2) years prior to the most recent financial statement of Tenant. Such statements shall be prepared in accordance with generally accepted accounting principles and shall be audited
by an independent certified public accountant. Failure of Tenant or Landlord, as the case may be, to timely execute, acknowledge and deliver such estoppel certificate or other instruments upon five (5) additional business days notice from the
Requesting Party advising the other party of the consequences of a non-response, shall constitute an acceptance of the premises stated herein and an acknowledgment by the other party that statements included in the estoppel certificate are true and
correct, without exception. 
  
 ARTICLE 18 
  
 SUBORDINATION 
  
 This Lease shall be subject and subordinate to all present and future ground
or underlying leases of the Building or Project and to the lien of any mortgage, trust deed or other encumbrances now or hereafter in force against the Building or Project or any part thereof, if any, and to all renewals, extensions, modifications,
consolidations and replacements thereof, and to all advances made or hereafter to be made upon the security of such mortgages or trust deeds, unless the holders of such mortgages, trust deeds or other encumbrances, or the lessors under 

 


					
	 	 	-23-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 such ground lease or underlying leases, require in writing that this Lease be superior thereto. In consideration of, and
as a condition precedent to, Tenant’s agreement to permit its interest pursuant to this Lease to be subordinated to any particular future ground or underlying lease of the Building or the Project or to the lien of any first mortgage or trust
deed, hereafter enforced against the Building or the Project and to any renewals, extensions, modifications, consolidations and replacements thereof, Landlord shall deliver to Tenant a commercially reasonable non-disturbance agreement executed by
the landlord under such ground lease or underlying lease or the holder of such mortgage or trust deed, as appropriate. Tenant covenants and agrees in the event any proceedings are brought for the foreclosure of any such mortgage or deed in lieu
thereof (or if any ground lease is terminated), to attorn, without any deductions or set-offs whatsoever, to the lienholder or purchaser or any successors thereto upon any such foreclosure sale or deed in lieu thereof (or to the ground lessor), if
so requested to do so by such purchaser or lienholder or ground lessor, and to recognize such purchaser or lienholder or ground lessor as the lessor under this Lease, provided such lienholder or purchaser or ground lessor shall agree to accept this
Lease and shall not disturb Tenant’s occupancy, so long as Tenant timely pays the rent and observes and performs the terms, covenants and conditions of this Lease to be observed and performed by Tenant. Landlord’s interest herein may be
assigned as security at any time to any lienholder. Tenant shall, within five (5) days of request by Landlord, execute such further commercially reasonable instruments or assurances as Landlord may reasonably deem necessary to evidence or confirm
the subordination or superiority of this Lease to any such mortgages, trust deeds, ground leases or underlying leases. Tenant waives the provisions of any current or future statute, rule or law which may give or purport to give Tenant any right or
election to terminate or otherwise adversely affect this Lease and the obligations of the Tenant hereunder in the event of any foreclosure proceeding or sale. Tenant shall, within five (5) days of request by Landlord from time to time, (i) execute a
commercially reasonable Nondisturbance and Attornment Agreement reasonably approved by Landlord’s mortgagee in favor of any mortgagee of the Building or Project, and (ii) execute any other form of commercially reasonable nondisturbance and
attornment agreement (or subordination, nondisturbance and attornment agreement, or subordination of the applicable mortgagee’s lien) reasonably required by any mortgagee of the Building or Project which provides comparable nondisturbance
protection to Tenant in the event of a foreclosure. 
  
 ARTICLE
19 
  
 DEFAULTS; REMEDIES 
  
 19.1 Events of Default. The occurrence of any of the following
shall constitute a default of this Lease by Tenant: 
  
 19.1.1
Any failure by Tenant to pay any Rent or any other charge required to be paid under this Lease, or any part thereof, when due unless such failure is cured within three (3) days after notice; or 
  
 19.1.2 Except where a specific time period is otherwise set forth for
Tenant’s performance in this Lease, in which event the failure to perform by Tenant within such time period shall be a default by Tenant under this Section 19.1.2, any failure by Tenant to observe or perform any other provision, covenant or
condition of this Lease to be observed or performed by Tenant where such failure continues for twenty (20) days after written notice thereof from Landlord to Tenant; provided that if the nature of such default is such that the same cannot reasonably
be cured within a twenty (20) day period, Tenant shall not be deemed to be in default if it diligently commences such cure within such period and thereafter diligently proceeds to rectify and cure such default, but in no event exceeding a period of
time in excess of sixty (60) days after written notice thereof from Landlord to Tenant; or 
  
 19.1.3 To the extent permitted by law, a general assignment by Tenant or any guarantor of the Lease for the benefit of creditors, or the taking of any corporate action in furtherance of bankruptcy or dissolution
whether or not there exists any proceeding under an insolvency or bankruptcy law, or the filing by or against Tenant or any guarantor of any proceeding under an insolvency or bankruptcy law, unless in the case of a proceeding filed against Tenant or
any guarantor the same is dismissed within sixty (60) days, or the appointment of a trustee or receiver to take possession of all or substantially all of the assets of Tenant or any guarantor, unless possession is restored to Tenant or such
guarantor within thirty (30) days, or any execution or other judicially authorized seizure of all or substantially all of Tenant’s assets located upon the Premises or of Tenant’s interest in this Lease, unless such seizure is discharged
within thirty (30) days; or 
  


					
	 	 	-24-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 19.1.4 Abandonment or vacation of all or a substantial portion of the Premises by Tenant; or 

 
 19.1.5 The failure by Tenant to observe or perform according to the
provisions of Articles 5, 14, 17 or 18 of this Lease where such failure continues for more than two (2) business days after notice from Landlord. 
  
 The notice periods provided herein are in lieu of, and not in addition to, any notice periods provided by law. 
  
 19.2 Remedies Upon Default. Upon the occurrence of any event of
default by Tenant, Landlord shall have, in addition to any other remedies available to Landlord at law or in equity (all of which remedies shall be distinct, separate and cumulative), 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. 
  
 19.2.1 Terminate this Lease, in which event Tenant shall immediately surrender the Premises to Landlord, and if Tenant fails to do so, Landlord may,
without prejudice to any other remedy which it may have for possession or arrearages in rent, enter upon and take possession of the Premises and expel or remove Tenant and any other person who may be occupying the Premises or any part thereof,
without being liable for prosecution or any claim or damages therefor; and Landlord may recover from Tenant the following: 
  
 (i) The worth at the time of award of any unpaid rent which has been earned at the time of such termination; plus 
  
 (ii) The worth at the time of award of the amount by which
the unpaid rent which would have been earned after termination until the time of award exceeds the amount of such rental loss that Tenant proves could have been reasonably avoided; plus 
  
 (iii) The worth at the time of award of the amount by which the unpaid rent for the balance of the Lease
Term after the time of award exceeds the amount of such rental loss that Tenant proves could have been reasonably avoided; plus 
  
 (iv) Any other amount necessary to compensate Landlord for all the detriment proximately caused by Tenant’s failure to perform its
obligations under this Lease or which in the ordinary course of things would be likely to result therefrom, specifically including but not limited to, brokerage commissions and advertising expenses incurred, expenses of remodeling the Premises or
any portion thereof for a new tenant, whether for the same or a different use, and any special concessions made to obtain a new tenant; and 
  
 (v) At Landlord’s election, such other amounts in addition to or in lieu of the foregoing as may be permitted from time to time by
applicable law. 
  
 The term “rent” as used in this
Section 19.2 shall be deemed to be and to mean all sums of every nature required to be paid by Tenant pursuant to the terms of this Lease, whether to Landlord or to others. As used in Paragraphs 19.2.1(i) and (ii), above, the “worth at the time
of award” shall be computed by allowing interest at the rate set forth in Article 25 of this Lease, but in no case greater than the maximum amount of such interest permitted by law. As used in Paragraph 19.2.1(iii) above, the “worth at the
time of award” shall be computed by discounting such amount at the discount rate of the Federal Reserve Bank of San Francisco at the time of award plus one percent (1%). 
  
 19.2.2 Landlord shall have the remedy described in California Civil Code Section 1951.4 (lessor may continue lease in effect
after lessee’s breach and abandonment and recover rent as it becomes due, if lessee has the right to sublet or assign, subject only to reasonable limitations). Accordingly, if Landlord does not elect to terminate this Lease on account of any
default by Tenant, Landlord may, from time to time, without terminating this Lease, enforce all of its rights and remedies under this Lease, including the right to recover all rent as it becomes due. 
  


					
	 	 	-25-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 19.2.3 Landlord shall at all times have the rights and remedies (which shall be cumulative with each
other and cumulative and in addition to those rights and remedies available under Sections 19.2.1 and 19.2.2, above, or any law or other provision of this Lease), without prior demand or notice except as required by applicable law, to seek any
declaratory, injunctive or other equitable relief, and specifically enforce this Lease, or restrain or enjoin a violation or breach of any provision hereof. 
  
 19.3 Subleases of Tenant. Whether or not Landlord elects to terminate this Lease on account of any default by Tenant, as set forth in this
Article 19, in the event of an event of default by Tenant, Landlord shall have the right to terminate any and all subleases, licenses, concessions or other consensual arrangements for possession entered into by Tenant and affecting the Premises
within ten (10) days of notice from Landlord, or may, in Landlord’s sole discretion, succeed to Tenant’s interest in such subleases, licenses, concessions or arrangements. In the event of Landlord’s election to succeed to
Tenant’s interest in any such subleases, licenses, concessions or arrangements, Tenant shall, as of the date of notice by Landlord of such election, have no further right to or interest in the rent or other consideration receivable thereunder.

  
 19.4 Form of Payment After Default. Following
the occurrence of two (2) separate events of monetary default by Tenant during any twelve (12) month period during the Lease Term, Landlord shall have the right to require that any or all subsequent amounts paid by Tenant to Landlord hereunder,
whether to cure the default in question or otherwise, be paid in the form of money order, cashier’s or certified check drawn on an institution acceptable to Landlord, or by other means reasonably approved by Landlord, notwithstanding any prior
practice of accepting payments in any different form. 
  
 19.5
Efforts to Relet. No re-entry or repossession, repairs, maintenance, changes, alterations and additions, reletting, appointment of a receiver to protect Landlord’s interests hereunder, or any other action or omission by Landlord
shall be construed as an election by Landlord to terminate this Lease or Tenant’s right to possession, or to accept a surrender of the Premises, nor shall same operate to release Tenant in whole or in part from any of Tenant’s obligations
hereunder, unless express written notice of such intention is sent by Landlord to Tenant. Tenant hereby irrevocably waives any right otherwise available under any law to redeem or reinstate this Lease. 
  
 ARTICLE 20 
  
 COVENANT OF QUIET ENJOYMENT 
  
 Landlord covenants that Tenant, on paying the Rent, charges for services and
other payments herein reserved and on keeping, observing and performing all the other terms, covenants, conditions, provisions and agreements herein contained on the part of Tenant to be kept, observed and performed, shall, during the Lease Term,
peaceably and quietly have, hold and enjoy the Premises subject to the terms, covenants, conditions, provisions and agreements hereof without interference by any persons lawfully claiming by or through Landlord. The foregoing covenant is in lieu of
any other covenant express or implied. 
  
 ARTICLE 21

  
 SECURITY DEPOSIT 
  
 Concurrent with Tenant’s execution of this Lease, Tenant shall deposit
with Landlord a security deposit (the “Security Deposit”) in the amount set forth in Section 8 of the Summary, as security for the faithful performance by Tenant of all of its obligations under this Lease. If Tenant defaults with
respect to any provisions of this Lease, including, but not limited to, the provisions relating to the payment of Rent, the removal of property and the repair of resultant damage, Landlord may, without notice to Tenant, but shall not be required to
apply all or any part of the Security Deposit for the payment of any Rent or any other sum in default and Tenant shall, upon demand therefor, restore the Security Deposit to its original amount. Any unapplied portion of the Security Deposit shall be
returned to Tenant, or, at Landlord’s option, to the last assignee of Tenant’s interest hereunder, within sixty (60) days following the expiration of the Lease Term. Tenant shall not be entitled to any interest on the Security Deposit.
Tenant hereby waives the provisions of Section 1950.7 of the California Civil Code, or any successor statute. 
  


					
	 	 	-26-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 ARTICLE 22 
  

SUBSTITUTION OF OTHER PREMISES 
  
 Landlord shall have the right to move Tenant to other space located on the sixth (6th) floor of the Building comparable to the Premises, in the same basic configuration as the Premises, and all terms hereof shall apply to the new space with
equal force. In such event, Landlord shall give Tenant not less than sixty (60) days prior notice, shall provide Tenant, at Landlord’s sole cost and expense, with tenant improvements at least equal in quality to those in the Premises and shall
move Tenant’s effects to the new space at Landlord’s sole cost and expense at such time and in such manner as to inconvenience Tenant as little as reasonably practicable. Landlord shall reimburse Tenant for Tenant’s reasonable, actual
out-of-pocket expenses incurred in connection with such relocation. Simultaneously with such relocation of the Premises, the parties shall immediately execute an amendment to this Lease stating the relocation of the Premises. 
  
 ARTICLE 23 
  
 SIGNS 
  
 23.1 Full Floors. Subject to Landlord’s prior written
approval, in its sole discretion, and provided all signs are in keeping with the quality, design and style of the Building and Project, Tenant, if the Premises comprise an entire floor of the Building, at its sole cost and expense, may install
identification signage anywhere in the Premises including in the elevator lobby of the Premises, provided that such signs must not be visible from the exterior of the Building. 
  
 23.2 Multi-Tenant Floors. If other tenants occupy space on the floor on which the Premises is located,
Tenant’s identifying signage shall be provided by Landlord, at Tenant’s cost, and such signage shall be comparable to that used by Landlord for other similar floors in the Building and shall comply with Landlord’s Building standard
signage program. 
  
 23.3 Prohibited Signage and Other
Items. Any signs, notices, logos, pictures, names or advertisements which are installed and that have not been separately approved by Landlord may be removed without notice by Landlord at the sole expense of Tenant. Tenant may not install
any signs on the exterior or roof of the Project or the Common Areas. Any signs, window coverings, or blinds (even if the same are located behind the Landlord-approved window coverings for the Building), or other items visible from the exterior of
the Premises or Building, shall be subject to the prior approval of Landlord, in its sole discretion. 
  
 23.4 Building Directory. Tenant shall be provided one (1) line per each 1,000 rentable square feet contained in the Premises to display
Tenant’s name and location in the Building on the Building directory located in the lobby of the Building, and the names of Tenant’s principal employees and subtenants. 
  
 ARTICLE 24 
  
 COMPLIANCE WITH LAW 
  
 Tenant shall not do anything or suffer anything to be done in or about the Premises or the Project which will in any way conflict with any law, statute,
ordinance or other governmental rule, regulation or requirement now in force or which may hereafter be enacted or promulgated (collectively, “Applicable Laws”). At its sole cost and expense, Tenant shall promptly comply with all
such Applicable Laws which relate to (i) Tenant’s use of the Premises, (ii) any Alterations made by Tenant to the Premises, and any tenant improvements in the Premises, or (iii) the Base Building, but as to the Base Building, only to the extent
such obligations are triggered by Alterations made by Tenant to the Premises, or the tenant improvements, or use of the Premises for non-typical general office use. Should any standard or regulation now or hereafter be imposed on Landlord or Tenant
by a state, federal or local governmental body charged with the establishment, regulation and enforcement of occupational, health or safety standards for employers, employees, landlords or tenants, then Tenant agrees, at its sole cost and expense,
to comply promptly with such standards or regulations. Tenant shall be responsible, at its sole cost and expense, to make all alterations to the Premises as are required to comply with 
  


					
	 	 	-27-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 the governmental rules, regulations, requirements or standards described in this Article 24. The judgment of any court of
competent jurisdiction or the admission of Tenant in any judicial action, regardless of whether Landlord is a party thereto, that Tenant has violated any of said governmental measures, shall be conclusive of that fact as between Landlord and Tenant.
Landlord shall comply with all Applicable Laws relating to the Base Building, provided that compliance with such Applicable Laws is not the responsibility of Tenant under this Lease, and provided further that Landlord’s failure to comply
therewith would prohibit Tenant from obtaining or maintaining a certificate of occupancy (or its equivalent) for the Premises, or would unreasonably and materially affect the safety of Tenant’s employees or create a significant health hazard
for Tenant’s employees. Landlord shall be permitted to include in Operating Expenses any costs or expenses incurred by Landlord under this Article 24 to the extent consistent with the terms of Section 4.2.4 above. 
  
 ARTICLE 25 
  
 LATE CHARGES 
  
 If any installment of Rent or any other sum due from Tenant shall not be
received by Landlord or Landlord’s designee within five (5) days after said amount is due, then Tenant shall pay to Landlord a late charge equal to ten percent (10%) of the overdue amount plus any attorneys’ fees incurred by Landlord by
reason of Tenant’s failure to pay Rent and/or other charges when due hereunder. The late charge shall be deemed Additional Rent and the right to require it shall be in addition to all of Landlord’s other rights and remedies hereunder or at
law and shall not be construed as liquidated damages or as limiting Landlord’s remedies in any manner. In addition to the late charge described above, any Rent or other amounts owing hereunder which are not paid within ten (10) days after the
date they are due shall bear interest from the date when due until paid at a rate per annum equal to the highest rate permitted by applicable law. 
  
 ARTICLE 26 
  
 LANDLORD’S RIGHT TO CURE DEFAULT; PAYMENTS BY TENANT 
  
 26.1 Landlord’s Cure. All covenants and agreements to be kept or performed by Tenant under this Lease shall be performed by Tenant at
Tenant’s sole cost and expense and without any reduction of Rent, except to the extent, if any, otherwise expressly provided herein. If Tenant shall fail to perform any obligation under this Lease, and such failure shall continue in excess of
the time allowed under Section 19.1.2, above, unless a specific time period is otherwise stated in this Lease, Landlord may, but shall not be obligated to, make any such payment or perform any such act on Tenant’s part without waiving its
rights based upon any default of Tenant and without releasing Tenant from any obligations hereunder. 
  
 26.2 Tenant’s Reimbursement. Except as may be specifically provided to the contrary in this Lease, Tenant shall pay to Landlord, upon
delivery by Landlord to Tenant of statements therefor: (i) sums equal to expenditures reasonably made and obligations incurred by Landlord in connection with the remedying by Landlord of Tenant’s defaults pursuant to the provisions of Section
26.1; (ii) sums equal to all losses, costs, liabilities, damages and expenses referred to in Article 10 of this Lease; and (iii) sums equal to all reasonable expenditures made and obligations incurred by Landlord in collecting or attempting to
collect the Rent or in enforcing or attempting to enforce any rights of Landlord under this Lease or pursuant to law, including, without limitation, all reasonable legal fees and other amounts so expended. Tenant’s obligations under this
Section 26.2 shall survive the expiration or sooner termination of the Lease Term. 
  
 ARTICLE 27 
  
 ENTRY
BY LANDLORD 
  
 Landlord reserves the right at all
reasonable times and upon not less than twenty-four (24) hours notice to Tenant (except in the case of an emergency) to enter the Premises to (i) inspect them; (ii) show the Premises to prospective purchasers, mortgagees or tenants, or to current or
prospective mortgagees, ground or underlying lessors or insurers; (iii) post notices of nonresponsibility; or (iv) alter, improve or repair the Premises, the premises of other tenants in 
  


					
	 	 	-28-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 the Building, or the Building, or for structural alterations, repairs, additions or improvements to the Building or the
Building’s systems and equipment. Tenant may have a representative of Tenant accompany Landlord during its entries (other than regularly scheduled entries made for the provision of janitorial services, etc.) provided that such representative is
made available at the time of such entry and does not interfere with Landlord’s entry onto the Premises in accordance with the terms of this Article 27. Notwithstanding anything to the contrary contained in this Article 27, Landlord may enter
the Premises at any time to (A) perform services required of Landlord, including janitorial service; (B) take possession due to any breach of this Lease in the manner provided herein; and (C) perform any covenants of Tenant which Tenant fails to
perform. Landlord may make any such entries without the abatement of Rent and may take such reasonable steps as required to accomplish the stated purposes. Tenant hereby waives any claims for damages or for any injuries or inconvenience to or
interference with Tenant’s business, lost profits, any loss of occupancy or quiet enjoyment of the Premises, and any other loss occasioned thereby. For each of the above purposes, Landlord shall at all times have a key with which to unlock all
the doors in the Premises, excluding Tenant’s vaults, safes and special security areas designated in advance by Tenant. In an emergency, Landlord shall have the right to use any means that Landlord may deem proper to open the doors in and to
the Premises. Any entry into the Premises by Landlord in the manner hereinbefore described shall not be deemed to be a forcible or unlawful entry into, or a detainer of, the Premises, or an actual or constructive eviction of Tenant from any portion
of the Premises. No provision of this Lease shall be construed as obligating Landlord to perform any repairs, alterations or decorations except as otherwise expressly agreed to be performed by Landlord herein. 
  
 ARTICLE 28 
  
 TENANT PARKING 
  
 Tenant shall rent from Landlord, commencing on the Lease Commencement Date,
the amount of parking passes set forth in Section 9 of the Summary, on a monthly basis throughout the Lease Term, which parking passes shall pertain to the Project parking facility. Tenant shall pay to Landlord for automobile parking passes on a
monthly basis the prevailing rate charged from time to time at the location of such parking passes. In addition, Tenant shall be responsible for the full amount of any taxes imposed by any governmental authority in connection with the renting of
such parking passes by Tenant or the use of the parking facility by Tenant. Tenant’s continued right to use the parking passes is conditioned upon Tenant abiding by all rules and regulations which are prescribed from time to time for the
orderly operation and use of the parking facility where the parking passes are located, including any sticker or other identification system established by Landlord, Tenant’s cooperation in seeing that Tenant’s employees and visitors also
comply with such rules and regulations and Tenant not being in default under this Lease. Landlord specifically reserves the right to change the location, size, configuration, design, layout and all other aspects of the Project parking facility at
any time and Tenant acknowledges and agrees that Landlord may, without incurring any liability to Tenant and without any abatement of Rent under this Lease, from time to time, close-off or restrict access to the Project parking facility for purposes
of permitting or facilitating any such construction, alteration or improvements or cease providing the parking passes if space is no longer available. Landlord may delegate its responsibilities hereunder to a parking operator in which case such
parking operator shall have all the rights of control attributed hereby to the Landlord. The parking passes rented by Tenant pursuant to this Article 28 are provided to Tenant solely for use by Tenant’s own personnel and such passes may not be
transferred, assigned, subleased or otherwise alienated by Tenant without Landlord’s prior approval. Tenant may validate visitor parking by such method or methods as the Landlord may establish, at the validation rate from time to time generally
applicable to visitor parking. 
  
 ARTICLE 29 
  
 MISCELLANEOUS PROVISIONS 
  
 29.1 Terms; Captions. The words “Landlord” and
“Tenant” as used herein shall include the plural as well as the singular. The necessary grammatical changes required to make the provisions hereof apply either to corporations or partnerships or individuals, men or women, as the case may
require, shall in all cases be assumed as though in each case fully expressed. The captions of Articles and Sections are for convenience only and shall not be deemed to limit, construe, affect or alter the meaning of such Articles and Sections.

  


					
	 	 	-29-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 29.2 Binding Effect. Subject to all other provisions of this Lease, each of the covenants,
conditions and provisions of this Lease shall extend to and shall, as the case may require, bind or inure to the benefit not only of Landlord and of Tenant, but also of their respective heirs, personal representatives, successors or assigns,
provided this clause shall not permit any assignment by Tenant contrary to the provisions of Article 14 of this Lease. 
  
 29.3 No Air Rights. No rights to any view or to light or air over any property, whether belonging to Landlord or any other person, are
granted to Tenant by this Lease. If at any time any windows of the Premises are temporarily darkened or the light or view therefrom is obstructed by reason of any repairs, improvements, maintenance or cleaning in or about the Project, the same shall
be without liability to Landlord and without any reduction or diminution of Tenant’s obligations under this Lease. 
  
 29.4 Modification of Lease. Should any current or prospective mortgagee or ground lessor for the Building or Project require a modification
of this Lease, which modification will not cause an increased cost or expense to Tenant or in any other way materially and adversely change the rights and obligations of Tenant hereunder, then and in such event, Tenant agrees that this Lease may be
so modified and agrees to execute whatever documents are reasonably required therefor and to deliver the same to Landlord within ten (10) days following a request therefor. At the request of Landlord or any mortgagee or ground lessor, Tenant agrees
to execute a short form of Lease and deliver the same to Landlord within ten (10) days following the request therefor. 
  
 29.5 Transfer of Landlord’s Interest. Tenant acknowledges that Landlord has the right to transfer all or any portion of its interest in
the Project or Building and in this Lease, and Tenant agrees that in the event of any such transfer, Landlord shall automatically be released from all liability under this Lease and Tenant agrees to look solely to such transferee for the performance
of Landlord’s obligations hereunder after the date of transfer and such transferee shall be deemed to have fully assumed and be liable for all obligations of this Lease to be performed by Landlord, including the return of any Security Deposit,
and Tenant shall attorn to such transferee. Tenant further acknowledges that Landlord may assign its interest in this Lease to a mortgage lender as additional security and agrees that such an assignment shall not release Landlord from its
obligations hereunder and that Tenant shall continue to look to Landlord for the performance of its obligations hereunder. 
  
 29.6 Prohibition Against Recording. Except as provided in Section 29.4 of this Lease, neither this Lease, nor any memorandum, affidavit or
other writing with respect thereto, shall be recorded by Tenant or by anyone acting through, under or on behalf of Tenant. 
  
 29.7 Landlord’s Title. Landlord’s title is and always shall be paramount to the title of Tenant. Nothing herein contained shall
empower Tenant to do any act which can, shall or may encumber the title of Landlord. 
  
 29.8 Relationship of Parties. Nothing contained in this Lease shall be deemed or construed by the parties hereto or by any third party to create the relationship of principal and agent, partnership,
joint venturer or any association between Landlord and Tenant. 
  
 29.9 Application of Payments. Landlord shall have the right to apply payments received from Tenant pursuant to this Lease, regardless of Tenant’s designation of such payments, to satisfy any obligations of Tenant
hereunder, in such order and amounts as Landlord, in its sole discretion, may elect. 
  
 29.10 Time of Essence. Time is of the essence with respect to the performance of every provision of this Lease in which time of performance is a factor. 
  
 29.11 Partial Invalidity. If any term, provision or condition
contained in this Lease shall, to any extent, be invalid or unenforceable, the remainder of this Lease, or the application of such term, provision or condition to persons or circumstances other than those with respect to which it is invalid or
unenforceable, shall not be affected thereby, and each and every other term, provision and condition of this Lease shall be valid and enforceable to the fullest extent possible permitted by law. 
  


					
	 	 	-30-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 29.12 No Warranty. In executing and delivering this Lease, Tenant has not relied on any
representations, including, but not limited to, any representation as to the amount of any item comprising Additional Rent or the amount of the Additional Rent in the aggregate or that Landlord is furnishing the same services to other tenants, at
all, on the same level or on the same basis, or any warranty or any statement of Landlord which is not set forth herein or in one or more of the exhibits attached hereto. 
  
 29.13 Landlord Exculpation. The liability of Landlord or the Landlord Parties to Tenant for any default by
Landlord under this Lease or arising in connection herewith or with Landlord’s operation, management, leasing, repair, renovation, alteration or any other matter relating to the Project or the Premises shall be limited solely and exclusively to
an amount which is equal to the interest of Landlord in the Building. Neither Landlord, nor any of the Landlord Parties shall have any personal liability therefor, and Tenant hereby expressly waives and releases such personal liability on behalf of
itself and all persons claiming by, through or under Tenant. The limitations of liability contained in this Section 29.13 shall inure to the benefit of Landlord’s and the Landlord Parties’ present and future partners, beneficiaries,
officers, directors, trustees, shareholders, agents and employees, and their respective partners, heirs, successors and assigns. Under no circumstances shall any present or future partner of Landlord (if Landlord is a partnership), or trustee or
beneficiary (if Landlord or any partner of Landlord is a trust), have any liability for the performance of Landlord’s obligations under this Lease. Notwithstanding any contrary provision herein, neither Landlord nor the Landlord Parties shall
be liable under any circumstances for injury or damage to, or interference with, Tenant’s business, including but not limited to, loss of profits, loss of rents or other revenues, loss of business opportunity, loss of goodwill or loss of use,
in each case, however occurring. 
  
 29.14 Entire
Agreement. It is understood and acknowledged that there are no oral agreements between the parties hereto affecting this Lease and this Lease constitutes the parties’ entire agreement with respect to the leasing of the Premises and
supersedes and cancels any and all previous negotiations, arrangements, brochures, agreements and understandings, if any, between the parties hereto or displayed by Landlord to Tenant with respect to the subject matter thereof, and none thereof
shall be used to interpret or construe this Lease. None of the terms, covenants, conditions or provisions of this Lease can be modified, deleted or added to except in writing signed by the parties hereto. 
  
 29.15 Right to Lease. Landlord reserves the absolute right to
effect such other tenancies in the Project as Landlord in the exercise of its sole business judgment shall determine to best promote the interests of the Building or Project. Tenant does not rely on the fact, nor does Landlord represent, that any
specific tenant or type or number of tenants shall, during the Lease Term, occupy any space in the Building or Project. 
  
 29.16 Force Majeure. Any prevention, delay or stoppage due to strikes, lockouts, labor disputes, acts of God, inability to obtain services,
labor, or materials or reasonable substitutes therefor, governmental actions, civil commotions, fire or other casualty, and other causes beyond the reasonable control of the party obligated to perform, except with respect to the obligations imposed
with regard to Rent and other charges to be paid by Tenant pursuant to this Lease and except as to Tenant’s obligations under Articles 5 and 24 of this Lease (collectively, a “Force Majeure”), notwithstanding anything to
the contrary contained in this Lease, shall excuse the performance of such party for a period equal to any such prevention, delay or stoppage and, therefore, if this Lease specifies a time period for performance of an obligation of either party,
that time period shall be extended by the period of any delay in such party’s performance caused by a Force Majeure. 
  
 29.17 Waiver of Redemption by Tenant. Tenant hereby waives, for Tenant and for all those claiming under Tenant, any and all rights now or
hereafter existing to redeem by order or judgment of any court or by any legal process or writ, Tenant’s right of occupancy of the Premises after any termination of this Lease. 
  
 29.18 Notices. All notices, demands, statements, designations, approvals or other communications
(collectively, “Notices”) given or required to be given by either party to the other hereunder or by law shall be in writing, shall be (A) sent by United States certified or registered mail, postage prepaid, return receipt requested
(“Mail”), (B) transmitted by telecopy, if such telecopy is promptly followed by a Notice sent by Mail, (C) delivered by a nationally recognized overnight courier, or (D) delivered personally. Any Notice shall be sent, transmitted,

  


					
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 or delivered, as the case may be, to Tenant or Landlord at the appropriate address set forth in Section 10 or 11 of the
Summary, as appropriate, or to such other place as either party may from time to time designate in a Notice to the other. Any Notice will be deemed given (i) three (3) days after the date it is posted if sent by Mail, (ii) the date the telecopy is
transmitted, (iii) the date the overnight courier delivery is made, or (iv) the date personal delivery is made or attempted to be made. If Tenant is notified of the identity and address of Landlord’s mortgagee or ground or underlying lessor,
Tenant shall give to such mortgagee or ground or underlying lessor written notice of any default by Landlord under the terms of this Lease by registered or certified mail, and such mortgagee or ground or underlying lessor shall be given a reasonable
opportunity to cure such default prior to Tenant’s exercising any remedy available to Tenant. 
  
 29.19 Joint and Several. If there is more than one Tenant, the obligations imposed upon Tenant under this Lease shall be joint and several.

  
 29.20 Authority. If Tenant is a corporation,
trust or partnership, each individual executing this Lease on behalf of Tenant hereby represents and warrants that Tenant is a duly formed and existing entity qualified to do business in California and that Tenant has full right and authority to
execute and deliver this Lease and that each person signing on behalf of Tenant is authorized to do so. In such event, Tenant shall, within ten (10) days after execution of this Lease, deliver to Landlord satisfactory evidence of such authority and,
if a corporation, upon demand by Landlord, also deliver to Landlord satisfactory evidence of (i) good standing in Tenant’s state of incorporation and (ii) qualification to do business in California. 
  
 29.21 Attorneys’ Fees. In the event that either Landlord
or Tenant should bring suit for the possession of the Premises, for the recovery of any sum due under this Lease, or because of the breach of any provision of this Lease or for any other relief against the other, then all costs and expenses,
including reasonable attorneys’ fees, incurred by the prevailing party therein shall be paid by the other party, which obligation on the part of the other party shall be deemed to have accrued on the date of the commencement of such action and
shall be enforceable whether or not the action is prosecuted to judgment. 
  
 29.22 Governing Law; WAIVER OF TRIAL BY JURY. This Lease shall be construed and enforced in accordance with the laws of the State of California. IN ANY ACTION OR PROCEEDING ARISING HEREFROM, LANDLORD AND
TENANT HEREBY CONSENT TO (I) THE JURISDICTION OF ANY COMPETENT COURT WITHIN THE STATE OF CALIFORNIA, (II) SERVICE OF PROCESS BY ANY MEANS AUTHORIZED BY CALIFORNIA LAW, AND (III) IN THE INTEREST OF SAVING TIME AND EXPENSE, TRIAL WITHOUT A JURY IN ANY
ACTION, PROCEEDING OR COUNTERCLAIM BROUGHT BY EITHER OF THE PARTIES HERETO AGAINST THE OTHER OR THEIR SUCCESSORS IN RESPECT OF ANY MATTER ARISING OUT OF OR IN CONNECTION WITH THIS LEASE, THE RELATIONSHIP OF LANDLORD AND TENANT, TENANT’S USE OR
OCCUPANCY OF THE PREMISES, AND/OR ANY CLAIM FOR INJURY OR DAMAGE, OR ANY EMERGENCY OR STATUTORY REMEDY. IN THE EVENT LANDLORD COMMENCES ANY SUMMARY PROCEEDINGS OR ACTION FOR NONPAYMENT OF BASE RENT OR ADDITIONAL RENT, TENANT SHALL NOT INTERPOSE ANY
COUNTERCLAIM OF ANY NATURE OR DESCRIPTION (UNLESS SUCH COUNTERCLAIM SHALL BE MANDATORY) IN ANY SUCH PROCEEDING OR ACTION, BUT SHALL BE RELEGATED TO AN INDEPENDENT ACTION AT LAW. 
  
 29.23 Submission of Lease. Submission of this instrument for examination or signature by Tenant does not
constitute a reservation of, option for or option to lease, and it is not effective as a lease or otherwise until execution and delivery by both Landlord and Tenant. 
  
 29.24 Brokers. Landlord and Tenant hereby warrant to each other that they have had no dealings with any real
estate broker or agent in connection with the negotiation of this Lease, excepting only the real estate brokers or agents specified in Section 12 of the Summary (the “Brokers”), and that they know of no other real estate broker or
agent who is entitled to a commission in connection with this Lease. Each party agrees to indemnify and defend the other party against and hold the other party harmless from any and all claims, demands, losses, liabilities, lawsuits, judgments,
costs and expenses (including without limitation reasonable attorneys’ fees) with respect to any leasing commission or equivalent compensation alleged to be owing on account of any dealings with any real estate broker or agent, other than the
Brokers, occurring by, through, or under the indemnifying party. 
  


					
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 29.25 Independent Covenants. This Lease shall be construed as though the covenants herein
between Landlord and Tenant are independent and not dependent and Tenant hereby expressly waives the benefit of any statute to the contrary and agrees that if Landlord fails to perform its obligations set forth herein, Tenant shall not be entitled
to make any repairs or perform any acts hereunder at Landlord’s expense or to any setoff of the Rent or other amounts owing hereunder against Landlord. 
  
 29.26 Project or Building Name and Signage. Landlord shall have the right at any time to change the name of the Project or Building and to
install, affix and maintain any and all signs on the exterior and on the interior of the Project or Building as Landlord may, in Landlord’s sole discretion, desire; provided, however that in the event Landlord changes the name or address of
the Building, and such change is not required by law, Landlord shall reimburse Tenant for the reasonable costs incurred as a result of changing Tenant’s business cards and stationery and other printed materials containing the Building name
and/or address. Tenant shall not use the name of the Project or Building or use pictures or illustrations of the Project or Building in advertising or other publicity or for any purpose other than as the address of the business to be conducted
by Tenant in the Premises, without the prior written consent of Landlord. 
  
 29.27 Counterparts. This Lease may be executed in counterparts with the same effect as if both parties hereto had executed the same document. Both counterparts shall be construed together and shall
constitute a single lease. 
  
 29.28
Confidentiality. Tenant acknowledges that the content of this Lease and any related documents are confidential information. Tenant shall keep such confidential information strictly confidential and shall not disclose such confidential
information to any person or entity other than Tenant’s financial, legal, and space planning consultants. 
  
 29.29 Transportation Management. Landlord has entered into an agreement with the Department of City Planning to implement a Transportation
Management Program (“TMP”) for tenants and their employees, and to participate in a program designed to coordinate commute alternatives, marketing, and brokerage for greater downtown employees. During the term of the TMP, Landlord
agrees to provide transportation brokerage and commute assistance services to Tenant, and to assist Tenant in meeting the transportation needs of its employees. Tenant agrees to cooperate with and assist Landlord’s TMP Coordinator
(“Coordinator”), through designation of a responsible employee, to distribute to Tenant’s employees written materials encouraging the use of public transit and ridesharing, and to distribute and return to the Coordinator
transportation survey questionnaire forms. 
  
 29.30
Building Renovations. It is specifically understood and agreed that Landlord has made no representation or warranty to Tenant and has no obligation and has made no promises to alter, remodel, improve, renovate, repair or decorate the
Premises, Building, or any part thereof and that no representations respecting the condition of the Project, Premises or the Building, or the areas in the vicinity of the Project have been made by Landlord to Tenant except as specifically set forth
herein. However, Tenant hereby acknowledges that Landlord is currently renovating or may during the Lease Term renovate, improve, alter, or modify (collectively, the “Renovations”) the Project, the Building and/or the Premises
including without limitation the parking structure, common areas, systems and equipment, roof, and structural portions of the same, which Renovations may include, without limitation, (i) installing sprinklers in the Building common areas and tenant
spaces, (ii) modifying the common areas and tenant spaces to comply with applicable laws and regulations, including regulations relating to the physically disabled, seismic conditions, and building safety and security, (iii) installing new floor
covering, lighting, and wall coverings in the Building common areas, and (iv) creating additional parking areas or occupied space within the Project, and in connection with any Renovations, Landlord may, among other things, erect scaffolding or
other necessary structures in the Building, limit or eliminate access to portions of the Project, including portions of the common areas, or perform work in the Building, which work may create noise, dust or leave debris in the Building. Similarly,
other properties in the vicinity of the Project may undergo substantial construction or renovation during the Lease Term (the “Area Renovations”), which may cause substantial disturbance to traffic and parking, and may cause dust,
noise and vibrations which may affect the Project. Tenant hereby agrees that such Renovations or Area Renovations and Landlord’s actions in connection with such Renovations or Area Renovations shall in no way constitute a constructive eviction
of Tenant nor entitle Tenant to any abatement of Rent. Landlord shall have no responsibility or for any reason be liable to Tenant for any direct or indirect injury to or 
  


					
	 	 	-33-	 	 CHINA BASIN LANDING
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 interference with Tenant’s business arising from the Renovations or Area Renovations, nor shall Tenant be entitled
to any compensation or damages from Landlord for loss of the use of the whole or any part of the Premises or of Tenant’s personal property or improvements resulting from the Renovations or Area Renovations or Landlord’s actions in
connection with such Renovations or Area Renovations, or for any inconvenience or annoyance occasioned by such Renovations or Area Renovations or Landlord’s actions. In connection with any Renovations or Area Renovations, Landlord shall use
commercially reasonable efforts to minimize interference with Tenant’s use of, and access to, the Premises. 
  
 29.31 No Violation. Tenant hereby warrants and represents that neither its execution of nor performance under this Lease shall cause Tenant
to be in violation of any agreement, instrument, contract, law, rule or regulation by which Tenant is bound, and Tenant shall protect, defend, indemnify and hold Landlord harmless against any claims, demands, losses, damages, liabilities, costs and
expenses, including, without limitation, reasonable attorneys’ fees and costs, arising from Tenant’s breach of this warranty and representation. 
  
 29.32 Communications and Computer Lines. Tenant may install, maintain, replace, remove or use any communications or computer wires and
cables (collectively, the “Lines”) at the Project in or serving the Premises, provided that (i) Tenant shall obtain Landlord’s prior written consent, use an experienced and qualified contractor approved in writing by Landlord,
and comply with all of the other provisions of Articles 7 and 8 of this Lease, (ii) an acceptable number of spare Lines and space for additional Lines shall be maintained for existing and future occupants of the Project, as determined in
Landlord’s reasonable opinion, (iii) the Lines therefor (including riser cables) shall be appropriately insulated to prevent excessive electromagnetic fields or radiation, and shall be surrounded by a protective conduit reasonably acceptable to
Landlord, (iv) any new or existing Lines servicing the Premises shall comply with all applicable governmental laws and regulations, (v) as a condition to permitting the installation of new Lines, Landlord may require that Tenant remove existing
Lines located in or serving the Premises and repair any damage in connection with such removal, and (vi) Tenant shall pay all costs in connection therewith. Landlord reserves the right to require that Tenant remove any Lines located in or serving
the Premises which are installed in violation of these provisions, or which are at any time in violation of any laws or represent a dangerous or potentially dangerous condition. Landlord makes no representation or assurances with regard to the
suitability, available or capacity of the Building’s telephone and communication distribution network or risers within or service to the Building for Tenant’s communication needs. 
  
 29.33 Development of the Project. 
  
 29.33.1 Subdivision. Landlord reserves the right to further
subdivide all or a portion of the Project. Tenant agrees to execute and deliver, upon demand by Landlord and in the form requested by Landlord, any additional documents needed to conform this Lease to the circumstances resulting from such
subdivision. 
  
 29.33.2 The Other Improvements. If
portions of the Project or property adjacent to the Project (collectively, the “Other Improvements”) are owned by an entity other than Landlord, Landlord, at its option, may enter into an agreement with the owner or owners of any or
all of the Other Improvements to provide (i) for reciprocal rights of access and/or use of the Project and the Other Improvements, (ii) for the common management, operation, maintenance, improvement and/or repair of all or any portion of the Project
and the Other Improvements, (iii) for the allocation of a portion of the Direct Expenses to the Other Improvements and the operating expenses and taxes for the Other Improvements to the Project, and (iv) for the use or improvement of the Other
Improvements and/or the Project in connection with the improvement, construction, and/or excavation of the Other Improvements and/or the Project. Nothing contained herein shall be deemed or construed to limit or otherwise affect Landlord’s
right to convey all or any portion of the Project or any other of Landlord’s rights described in this Lease. 
  
 29.33.3 Construction of Project and Other Improvements. Tenant acknowledges that portions of the Project and/or the Other Improvements may
be under construction following Tenant’s occupancy of the Premises, and that such construction may result in levels of noise, dust, obstruction of access, etc. which are in excess of that present in a fully constructed project. Tenant hereby
waives any and all rent offsets or claims of constructive eviction which may arise in connection with such construction. In connection with any construction in accordance with the terms of this Section 29.33, Landlord shall use commercially
reasonable efforts to minimize interference with Tenant’s use of, and access to, the Premises. 
  


					
	 	 	-34-	 	 CHINA BASIN LANDING
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 IN WITNESS WHEREOF, Landlord and Tenant have caused this Lease to be executed the day and date first
above written. 
  

					
	 “Landlord”:

	
	 STOCKBRIDGE/MCC-CHINA BASIN, L.L.C.,

	 a Delaware limited liability company

		
	 By:
	 	     /s/ Kevin D. Cox


	 	 	Its:	 	Authorized Representative
	
	 “Tenant”:

	
	 SIRNA THERAPEUTICS, INC.,

	 a Delaware corporation,

		
	 By:
	 	     /s/ Martin Schmeig


	 	 	Its:	 	Senior Vice President and CFO
		
	 By:
	 	     /s/ Bharat Chowrira


	 	 	Its:	 	VP Legal Affairs


  


					
	 	 	-35-	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 EXHIBIT A 
  
 CHINA BASIN LANDING 
  
 OUTLINE OF PREMISES 
  
  


					
	 	 	 EXHIBIT A
 -1-
	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 EXHIBIT B 
  
 CHINA BASIN LANDING 
  
  


					
	 	 	 EXHIBIT B
 -1-
	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 EXHIBIT C 
  
 CHINA BASIN LANDING 
  

NOTICE OF LEASE TERM DATES 
  

					
	 To:
	 	  

	 	 
	 	 	  

	 	 
	 	 	  

	 	 
	 	 	  

	 	 

  

	 	Re:	Office Lease dated                     , 20    
between                     , a
                     (“Landlord”), and
                    , a
                     (“Tenant”) concerning Suite              on
floor(s)                      of the office building located at
                            , San Francisco, California. 

  
 Gentlemen: 
  
 In accordance with the Office Lease (the “Lease”), we wish to advise you and/or confirm as follows: 
  

	 	1.	The Lease Term shall commence on or has commenced on                     
for a term of                      ending on
                    . 

  

	 	2.	Rent commenced to accrue on                     , in the amount of
                    . 

  

	 	3.	If the Lease Commencement Date is other than the first day of the month, the first billing will contain a pro rata adjustment. Each billing thereafter, with the exception of the
final billing, shall be for the full amount of the monthly installment as provided for in the Lease. 

  

	 	4.	Your rent checks should be made payable to                      at
                    . 

  

	 	5.	The exact number of rentable/usable square feet within the Premises is
                     square feet. 

  

	 	6.	Tenant’s Share as adjusted based upon the exact number of usable square feet within the Premises is
            %. 

  


					
	 	 	 EXHIBIT C
 -1-
	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 This Commencement Letter shall be deemed accepted by Tenant if not executed and returned to Landlord by
Tenant within thirty (30) days following the date that Landlord delivers this Commencement Letter to Tenant for execution. 
  

			
	“Landlord”:
	
	                                      
                                        
                        ,
	a                                      
                                        
                       
		
	By:	 	  


	    Its:	 	  




  
 Agreed to and Accepted

 as of                     ,
20    . 
  
 “Tenant”: 
  

			
	                                      
                                        
                         
	a                                      
                                        
                       
		
	By:	 	  


	    Its:	 	  



  


					
	 	 	 EXHIBIT C
 -2-
	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 EXHIBIT D 
  
 CHINA BASIN LANDING 
  
 RULES AND REGULATIONS 
  
 Tenant shall faithfully observe and comply with the following Rules and Regulations. Landlord shall not be responsible to Tenant for the nonperformance of
any of said Rules and Regulations by or otherwise with respect to the acts or omissions of any other tenants or occupants of the Project. In the event of any conflict between the Rules and Regulations and the other provisions of this Lease, the
latter shall control. 
  
 1. Tenant shall not alter any lock or
install any new or additional locks or bolts on any doors or windows of the Premises without obtaining Landlord’s prior written consent. Tenant shall bear the cost of any lock changes or repairs required by Tenant. Two keys will be furnished by
Landlord for the Premises, and any additional keys required by Tenant must be obtained from Landlord at a reasonable cost to be established by Landlord. Upon the termination of this Lease, Tenant shall restore to Landlord all keys of stores,
offices, and toilet rooms, either furnished to, or otherwise procured by, Tenant and in the event of the loss of keys so furnished, Tenant shall pay to Landlord the cost of replacing same or of changing the lock or locks opened by such lost key if
Landlord shall deem it necessary to make such changes. 
  
 2. All
doors opening to public corridors shall be kept closed at all times except for normal ingress and egress to the Premises. 
  
 3. Landlord reserves the right to close and keep locked all entrance and exit doors of the Building during such hours as are customary for comparable
buildings in the vicinity of the Building. Tenant, its employees and agents must be sure that the doors to the Building are securely closed and locked when leaving the Premises if it is after the normal hours of business for the Building. Any
tenant, its employees, agents or any other persons entering or leaving the Building at any time when it is so locked, or any time when it is considered to be after normal business hours for the Building, may be required to sign the Building
register. Access to the Building may be refused unless the person seeking access has proper identification or has a previously arranged pass for access to the Building. Landlord will furnish passes to persons for whom Tenant requests same in
writing. Tenant shall be responsible for all persons for whom Tenant requests passes and shall be liable to Landlord for all acts of such persons. The Landlord and his agents shall in no case be liable for damages for any error with regard to the
admission to or exclusion from the Building of any person. In case of invasion, mob, riot, public excitement, or other commotion, Landlord reserves the right to prevent access to the Building or the Project during the continuance thereof by any
means it deems appropriate for the safety and protection of life and property. 
  
 4. No furniture, freight or equipment of any kind shall be brought into the Building without prior notice to Landlord. All moving activity into or out of the Building shall be scheduled with Landlord and done only at
such time and in such manner as Landlord designates. Landlord shall have the right to prescribe the weight, size and position of all safes and other heavy property brought into the Building and also the times and manner of moving the same in and out
of the Building. Safes and other heavy objects shall, if considered necessary by Landlord, stand on supports of such thickness as is necessary to properly distribute the weight. Landlord will not be responsible for loss of or damage to any such safe
or property in any case. Any damage to any part of the Building, its contents, occupants or visitors by moving or maintaining any such safe or other property shall be the sole responsibility and expense of Tenant. 
  
 5. No furniture, packages, supplies, equipment or merchandise will be
received in the Building or carried up or down in the elevators, except between such hours, in such specific elevator and by such personnel as shall be designated by Landlord. 
  
 6. The requirements of Tenant will be attended to only upon application at the management office for the Project or at such
office location designated by Landlord. Employees of Landlord shall not perform any work or do anything outside their regular duties unless under special instructions from Landlord. 
  


					
	 	 	 EXHIBIT D
 -1-
	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 7. No sign, advertisement, notice or handbill shall be exhibited, distributed, painted or affixed by
Tenant on any part of the Premises or the Building without the prior written consent of the Landlord. Tenant shall not disturb, solicit, peddle, or canvass any occupant of the Project and shall cooperate with Landlord and its agents of Landlord to
prevent same. 
  
 8. The toilet rooms, urinals, wash bowls and
other apparatus shall not be used for any purpose other than that for which they were constructed, and no foreign substance of any kind whatsoever shall be thrown therein. The expense of any breakage, stoppage or damage resulting from the violation
of this rule shall be borne by the tenant who, or whose servants, employees, agents, visitors or licensees shall have caused same. 
  
 9. Tenant shall not overload the floor of the Premises, nor mark, drive nails or screws, or drill into the partitions, woodwork or drywall or in any way
deface the Premises or any part thereof without Landlord’s prior written consent. Tenant shall not purchase spring water, ice, towel, linen, maintenance or other like services from any person or persons not approved by Landlord. 
  
 10. Except for vending machines intended for the sole use of Tenant’s
employees and invitees, no vending machine or machines other than fractional horsepower office machines shall be installed, maintained or operated upon the Premises without the written consent of Landlord. 
  
 11. Tenant shall not use or keep in or on the Premises, the Building, or the
Project any kerosene, gasoline, explosive material, corrosive material, material capable of emitting toxic fumes, or other inflammable or combustible fluid chemical, substitute or material. Tenant shall provide material safety data sheets for any
Hazardous Material used or kept on the Premises. 
  
 12. Tenant
shall not without the prior written consent of Landlord use any method of heating or air conditioning other than that supplied by Landlord. 
  
 13. Tenant shall not use, keep or permit to be used or kept, any foul or noxious gas or substance in or on the Premises, or permit or allow the Premises
to be occupied or used in a manner offensive or objectionable to Landlord or other occupants of the Project by reason of noise, odors, or vibrations, or interfere with other tenants or those having business therein, whether by the use of any musical
instrument, radio, phonograph, or in any other way. Tenant shall not throw anything out of doors, windows or skylights or down passageways. 
  
 14. Tenant shall not bring into or keep within the Project, the Building or the Premises any animals, birds, aquariums, or, except in areas designated by
Landlord, bicycles or other vehicles. 
  
 15. No cooking shall be
done or permitted on the Premises, nor shall the Premises be used for the storage of merchandise, for lodging or for any improper, objectionable or immoral purposes. Notwithstanding the foregoing, Underwriters’ laboratory-approved equipment and
microwave ovens may be used in the Premises for heating food and brewing coffee, tea, hot chocolate and similar beverages for employees and visitors, provided that such use is in accordance with all applicable federal, state, county and city laws,
codes, ordinances, rules and regulations. 
  
 16. The Premises
shall not be used for manufacturing or for the storage of merchandise except as such storage may be incidental to the use of the Premises provided for in the Summary. Tenant shall not occupy or permit any portion of the Premises to be occupied as an
office for a messenger-type operation or dispatch office, public stenographer or typist, or for the manufacture or sale of liquor, narcotics, or tobacco in any form, or as a medical office, or as a barber or manicure shop, or as an employment bureau
without the express prior written consent of Landlord. Tenant shall not engage or pay any employees on the Premises except those actually working for such tenant on the Premises nor advertise for laborers giving an address at the Premises.

  
 17. Landlord reserves the right to exclude or expel from the
Project any person who, in the judgment of Landlord, is intoxicated or under the influence of liquor or drugs, or who shall in any manner do any act in violation of any of these Rules and Regulations. 
  
 18. Tenant, its employees and agents shall not loiter in or on the entrances,
corridors, sidewalks, lobbies, courts, halls, stairways, elevators, vestibules or any Common Areas for the purpose of smoking tobacco products or for any other purpose, nor in any way obstruct such areas, and shall use them only as a means of
ingress and egress for the Premises. 
  


					
	 	 	 EXHIBIT D
 -2-
	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 19. Tenant shall not waste electricity, water or air conditioning and agrees to cooperate fully with
Landlord to ensure the most effective operation of the Building’s heating and air conditioning system, and shall refrain from attempting to adjust any controls. Tenant shall participate in recycling programs undertaken by Landlord 

 
 20. Tenant shall store all its trash and garbage within the interior of
the Premises. No material shall be placed in the trash boxes or receptacles if such material is of such nature that it may not be disposed of in the ordinary and customary manner of removing and disposing of trash and garbage in San Francisco,
California without violation of any law or ordinance governing such disposal. All trash, garbage and refuse disposal shall be made only through entry-ways and elevators provided for such purposes at such times as Landlord shall designate. If the
Premises is or becomes infested with vermin as a result of the use or any misuse or neglect of the Premises by Tenant, its agents, servants, employees, contractors, visitors or licensees, Tenant shall forthwith, at Tenant’s expense, cause the
Premises to be exterminated from time to time to the satisfaction of Landlord and shall employ such licensed exterminators as shall be approved in writing in advance by Landlord. 
  
 21. Tenant shall comply with all safety, fire protection and evacuation procedures and regulations established by Landlord
or any governmental agency. 
  
 22. Any persons employed by Tenant
to do janitorial work shall be subject to the prior written approval of Landlord, and while in the Building and outside of the Premises, shall be subject to and under the control and direction of the Building manager (but not as an agent or servant
of such manager or of Landlord), and Tenant shall be responsible for all acts of such persons. 
  
 23. No awnings or other projection shall be attached to the outside walls of the Building without the prior written consent of Landlord, and no curtains, blinds, shades or screens shall be attached to or hung in, or
used in connection with, any window or door of the Premises other than Landlord standard drapes. All electrical ceiling fixtures hung in the Premises or spaces along the perimeter of the Building must be fluorescent and/or of a quality, type, design
and a warm white bulb color approved in advance in writing by Landlord. Neither the interior nor exterior of any windows shall be coated or otherwise sunscreened without the prior written consent of Landlord. Tenant shall be responsible for any
damage to the window film on the exterior windows of the Premises and shall promptly repair any such damage at Tenant’s sole cost and expense. Tenant shall keep its window coverings closed during any period of the day when the sun is shining
directly on the windows of the Premises. Prior to leaving the Premises for the day, Tenant shall draw or lower window coverings and extinguish all lights. Tenant shall abide by Landlord’s regulations concerning the opening and closing of window
coverings which are attached to the windows in the Premises, if any, which have a view of any interior portion of the Building or Building Common Areas. 
  
 24. The sashes, sash doors, skylights, windows, and doors that reflect or admit light and air into the halls, passageways or other public places in the
Building shall not be covered or obstructed by Tenant, nor shall any bottles, parcels or other articles be placed on the windowsills. 
  
 25. Tenant must comply with requests by the Landlord concerning the informing of their employees of items of importance to the Landlord. 
  
 26. Tenant must comply with all city and state NO-SMOKING” ordinances.
If Tenant is required under any ordinance to adopt a written smoking policy, a copy of said policy shall be on file in the office of the Building. 
  
 27. Tenant hereby acknowledges that Landlord shall have no obligation to provide guard service or other security measures for the benefit of the Premises,
the Building or the Project. Tenant hereby assumes all responsibility for the protection of Tenant and its agents, employees, contractors, invitees and guests, and the property thereof, from acts of third parties, including keeping doors locked and
other means of entry to the Premises closed, whether or not Landlord, at its option, elects to provide security protection for the Project or any portion thereof. Tenant further assumes the risk that any safety and security devices, services and
programs 
  


					
	 	 	 EXHIBIT D
 -3-
	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 which Landlord elects, in its sole discretion, to provide may not be effective, or may malfunction or be circumvented by
an unauthorized third party, and Tenant shall, in addition to its other insurance obligations under this Lease, obtain its own insurance coverage to the extent Tenant desires protection against losses related to such occurrences. Tenant shall
cooperate in any reasonable safety or security program developed by Landlord or required by law. 
  
 28. All office equipment of any electrical or mechanical nature shall be placed by Tenant in the Premises in settings approved by Landlord, to absorb or
prevent any vibration, noise and annoyance. 
  
 29. Tenant shall
not use in any space or in the public halls of the Building, any hand trucks except those equipped with rubber tires and rubber side guards. 
  
 30. No auction, liquidation, fire sale, going-out-of-business or bankruptcy sale shall be conducted in the Premises without the prior written consent of
Landlord. 
  
 31. No tenant shall use or permit the use of any
portion of the Premises for living quarters, sleeping apartments or lodging rooms. 
  
 32. Tenant shall not purchase spring water, towels, janitorial or maintenance or other similar services from any company or persons not approved by Landlord. Landlord shall approve a sufficient number of sources of
such services to provide Tenant with a reasonable selection, but only in such instances and to such extent as Landlord in its judgment shall consider consistent with the security and proper operation of the Building. 
  
 33. Tenant shall install and maintain, at Tenant’s sole cost and
expense, an adequate, visibly marked and properly operational fire extinguisher next to any duplicating or photocopying machines or similar heat producing equipment, which may or may not contain combustible material, in the Premises. 
  
 Landlord reserves the right at any time to change or rescind any one or more
of these Rules and Regulations, or to make such other and further reasonable Rules and Regulations as in Landlord’s judgment may from time to time be necessary for the management, safety, care and cleanliness of the Premises, Building, the
Common Areas and the Project, and for the preservation of good order therein, as well as for the convenience of other occupants and tenants therein. Landlord may waive any one or more of these Rules and Regulations for the benefit of any particular
tenants, but no such waiver by Landlord shall be construed as a waiver of such Rules and Regulations in favor of any other tenant, nor prevent Landlord from thereafter enforcing any such Rules or Regulations against any or all tenants of the
Project. Tenant shall be deemed to have read these Rules and Regulations and to have agreed to abide by them as a condition of its occupancy of the Premises. 
  


					
	 	 	 EXHIBIT D
 -4-
	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 EXHIBIT E 
  
 CHINA BASIN LANDING 
  

FORM OF TENANT’S ESTOPPEL CERTIFICATE 
  
 The undersigned as Tenant under that certain Office Lease (the “Lease”) made and entered into as of
                    , 20     by and between
                     as Landlord, and the undersigned as Tenant, for Premises on the
                     floor(s) of the office building located at
                    , San Francisco, California
                    , certifies as follows: 
  
 1. Attached hereto as Exhibit A is a true and correct copy of the Lease and all amendments and modifications thereto. The documents contained in Exhibit A
represent the entire agreement between the parties as to the Premises and the project of which the Premises are a part. 
  
 2. The undersigned currently occupies the Premises described in the Lease, the Lease Term commenced on
                    , and the Lease Term expires on
                    , and the undersigned has no option to terminate or cancel the Lease or to purchase all or any part of the Premises, the
Building and/or the Project. 
  
 3. Base Rent became payable on
                    . 
  
 4. The Lease is in full force and effect and has not been modified, supplemented or amended in any way except as provided in Exhibit A. 
  
 5. Tenant has not transferred, assigned, or sublet any portion of the
Premises nor entered into any license or concession agreements with respect thereto except as follows: 
  
 6. Tenant shall not modify the documents contained in Exhibit A without the prior written consent of Landlord’s mortgagee. 
  
 7. All monthly installments of Base Rent, all Additional Rent and all monthly
installments of estimated Additional Rent have been paid when due through                     . The current monthly installment of Base Rent
is $                            . 
  
 8. All conditions of the Lease to be performed by Landlord necessary to the enforceability of the Lease have been satisfied
and Landlord is not in default thereunder. In addition, the undersigned has not delivered any notice to Landlord regarding a default by Landlord thereunder. 
  
 9. No rental has been paid more than thirty (30) days in advance and no security has been deposited with Landlord except as provided in the Lease.

  
 10. As of the date hereof, there are no existing defenses or
offsets, to the undersigned’s knowledge, claims or any basis for a claim, that the undersigned has against Landlord. 
  
 11. If Tenant is a corporation or partnership, each individual executing this Estoppel Certificate on behalf of Tenant hereby represents and warrants that
Tenant is a duly formed and existing entity qualified to do business in California and that Tenant has full right and authority to execute and deliver this Estoppel Certificate and that each person signing on behalf of Tenant is authorized to do so.

  
 12. There are no actions pending against the undersigned or
any guarantor of the Lease under the bankruptcy or similar laws of the United States or any state. 
  


					
	 	 	 EXHIBIT E
 -1-
	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 13. Other than in compliance with all applicable laws and incidental to the ordinary course of the use of
the Premises, the undersigned has not used or stored any hazardous substances in the Premises. 
  
 14. To the undersigned’s knowledge, all tenant improvement work to be performed by Landlord under the Lease has been completed in accordance with the Lease and has been accepted by the undersigned and all
reimbursements and allowances due to the undersigned under the Lease in connection with any tenant improvement work have been paid in full. 
  
 The undersigned acknowledges that this Estoppel Certificate may be delivered to Landlord or to a prospective mortgagee or prospective purchaser, and
acknowledges that said prospective mortgagee or prospective purchaser will be relying upon the statements contained herein in making the loan or acquiring the property of which the Premises are a part and that receipt by it of this certificate is a
condition of making such loan or acquiring such property. 
  
 Executed at                      on the              day of
                    , 20    . 
  
  
  

			
	“Tenant”:
	
	                                      
                                        
                        ,
	a                                      
                                        
                       
		
	By:	 	  


	    Its:	 	  


		
	By:	 	  


	    Its:	 	  




  
  


					
	 	 	 EXHIBIT E
 -2-
	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 OFFICE LEASE 
  
 CHINA BASIN LANDING 
  
  
 STOCKBRIDGE/MCC-CHINA BASIN, L.L.C., 
  
 a Delaware limited liability company, 
  
 as Landlord, 
  
 and 
  
 SIRNA THERAPEUTICS, INC., 
  
 a Delaware corporation, 
  
 as Tenant 
  
  


					
	 	 	 	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 TABLE OF CONTENTS 
  

					
	 	  	 	  	PAGE
	 ARTICLE 1
	  	PREMISES, BUILDING, PROJECT, AND COMMON AREAS	  	3
			
	 ARTICLE 2
	  	LEASE TERM	  	4
			
	 ARTICLE 3
	  	BASE RENT	  	5
			
	 ARTICLE 4
	  	ADDITIONAL RENT	  	5
			
	 ARTICLE 5
	  	USE OF PREMISES	  	10
			
	 ARTICLE 6
	  	SERVICES AND UTILITIES	  	11
			
	 ARTICLE 7
	  	REPAIRS	  	13
			
	 ARTICLE 8
	  	ADDITIONS AND ALTERATIONS	  	13
			
	 ARTICLE 9
	  	COVENANT AGAINST LIENS	  	15
			
	 ARTICLE 10
	  	INSURANCE	  	15
			
	 ARTICLE 11
	  	DAMAGE AND DESTRUCTION	  	17
			
	 ARTICLE 12
	  	NONWAIVER	  	18
			
	 ARTICLE 13
	  	CONDEMNATION	  	19
			
	 ARTICLE 14
	  	ASSIGNMENT AND SUBLETTING	  	19
			
	 ARTICLE 15
	  	SURRENDER OF PREMISES; OWNERSHIP AND REMOVAL OF TRADE FIXTURES	  	22
			
	 ARTICLE 16
	  	HOLDING OVER	  	23
			
	 ARTICLE 17
	  	ESTOPPEL CERTIFICATES	  	23
			
	 ARTICLE 18
	  	SUBORDINATION	  	23
			
	 ARTICLE 19
	  	DEFAULTS; REMEDIES	  	24
			
	 ARTICLE 20
	  	COVENANT OF QUIET ENJOYMENT	  	26
			
	 ARTICLE 21
	  	SECURITY DEPOSIT	  	26
			
	 ARTICLE 22
	  	SUBSTITUTION OF OTHER PREMISES	  	27
			
	 ARTICLE 23
	  	SIGNS	  	27
			
	 ARTICLE 24
	  	COMPLIANCE WITH LAW	  	27
			
	 ARTICLE 25
	  	LATE CHARGES	  	28
			
	 ARTICLE 26
	  	LANDLORD'S RIGHT TO CURE DEFAULT; PAYMENTS BY TENANT	  	28
			
	 ARTICLE 27
	  	ENTRY BY LANDLORD	  	28
			
	 ARTICLE 28
	  	TENANT PARKING	  	29
			
	 ARTICLE 29
	  	MISCELLANEOUS PROVISIONS	  	29

  


					
	 	 	(i)	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]










 INDEX 
  

				
	 	  	PAGE 	(S)
	 Abatement Event
	  	12	 
	 Additional Rent
	  	5	 
	 Alterations
	  	13	 
	 Area Renovations
	  	33	 
	 Base Building
	  	13	 
	 Base Rent
	  	5	 
	 Base Year
	  	6	 
	 Brokers
	  	32	 
	 Building
	  	3	 
	 Building Common Areas
	  	3	 
	 Building Hours
	  	11	 
	 China Basin Landing
	  	3	 
	 Common Areas
	  	3	 
	 Coordinator
	  	33	 
	 Cost Pools
	  	9	 
	 Direct Expenses
	  	6	 
	 Eligibility Period
	  	12	 
	 Estimate
	  	9	 
	 Estimate Statement
	  	9	 
	 Estimated Excess
	  	9	 
	 Excess
	  	9	 
	 Expense Year
	  	6	 
	 Force Majeure
	  	31	 
	 Holidays
	  	11	 
	 HVAC
	  	11	 
	 Landlord
	  	1	 
	 Landlord Parties
	  	15	 
	 Landlord Repair Notice
	  	17	 
	 Lease
	  	1	 
	 Lease Commencement Date
	  	4	 
	 Lease Expiration Date
	  	4	 
	 Lease Term
	  	4	 
	 Lease Year
	  	4	 
	 Lines
	  	34	 
	 Mail
	  	31	 
	 Notices
	  	31	 
	 Operating Expenses
	  	6	 
	 Option Rent
	  	4	 
	 Option Term
	  	4	 
	 Original Tenant
	  	4	 
	 Other Improvements
	  	34	 
	 Premises
	  	3	 
	 Project
	  	3	 
	 Project Common Areas
	  	3	 
	 Proposition 13
	  	8	 
	 Renovations
	  	33	 
	 Rent
	  	5	 
	 Requesting Party
	  	23	 
	 Security Deposit
	  	26	 
	 Statement
	  	9	 
	 Subject Space
	  	19	 
	 Summary
	  	1	 
	 Tax Expenses
	  	8	 
	 Tenant
	  	1	 
	 Tenant Personal Property
	  	22	 
	 Tenant’s Share
	  	9	 
	 TMP
	  	33	 
	 Transfer
	  	21	 
	 Transfer Notice
	  	19	 
	 Transfer Premium
	  	21	 
	 Transferee
	  	19	 
	 Transfers
	  	19	 

  


					
	 	 	(ii)	 	 CHINA BASIN LANDING
 [Sirna Therapeutics, Inc.]