Exhibit 10.33

LEASE AGREEMENT

     THIS LEASE AGREEMENT (this “Lease”) is made this 9 day of July, 2010, between ARE-SAN FRANCISCO NO. 12, LLC, a Delaware limited liability company (“Landlord”), and ONYX PHARMACEUTICALS, INC., a Delaware corporation (“Tenant”).

Address:		249 East Grand Avenue, South San Francisco, California
Premises:		That portion of the Project, consisting of the first and second floors of the Building, containing approximately 57,755 rentable square feet, as determined by Landlord, as shown on Exhibit A, subject to adjustment as provided for in Section 41 hereof.
Project:		The real property on which the building (the “Building”) in which the Premises are located, together with all improvements thereon and appurtenances thereto as described on Exhibit B.
Base Rent:		$2.85 per rentable square foot of the Premises per month

Rentable Area of Premises: 57,755 sq. ft., subject to adjustment as provided for in Section 41 hereof.

Rentable Area of Building: 129,501 sq. ft.

Rentable Area of Project: 129,501 sq. ft., subject to adjustment as provided form in Section 5 hereof

Building’s Share of Project: 100%

Tenant’s Share of Operating Expenses of Building: 44.6%, subject to adjustment as provided for in Section 41 hereof.

Tenant’s Share of Operating Expenses of Project: 44.6%, subject to adjustment as provided for in Section 5 and Section 41 hereof.

Security Deposit: $164,601

Rent Adjustment Percentage: 3%

Base Term:		Beginning on the Commencement Date and ending 120 months from the first day of the first full month following the Rent Commencement Date.
Permitted Use:		Research and development laboratory, office and other uses consistent with the character of the Project and otherwise in compliance with the provisions of Section 7 hereof.

Address for Rent Payment:		Landlord’s Notice Address:
P.O. Box 975383		385 E. Colorado Boulevard, Suite 299
Dallas, TX 75397-5383		Pasadena, CA 91101
		Attention: Corporate Secretary
Tenant’s Notice Address:
After Tenant Occupies the Building:		Before Tenant Occupies the Building:
249 E. Grand Avenue		2100 Powell Street
South San Francisco, CA 94080		Emeryville, CA 94608
Attention: General Counsel		Attention: General Counsel

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

þ EXHIBIT A — PREMISES DESCRIPTION		þ EXHIBIT B — DESCRIPTION OF PROJECT
þ EXHIBIT C — WORK LETTER		þ EXHIBIT D — COMMENCEMENT DATE
þ EXHIBIT E — RULES AND REGULATIONS		þ EXHIBIT F — TENANT’S PERSONAL PROPERTY
þ EXHIBIT G — NORTHERN FACILITY LAND		þ EXHIBIT H — APPROVED SIGNAGE
þ EXHIBIT I — INTENTIONALLY OMITTED		þ EXHIBIT J — SITE PLAN

     1. Lease of Premises. Upon and subject to all of the terms and conditions hereof, Landlord hereby leases the Premises to Tenant and Tenant hereby leases the Premises from Landlord. The portions of the Project which are for the non-exclusive use of tenants of the Project are collectively referred to herein as the “Common Areas.” Landlord reserves the right to modify Common Areas, provided that such modifications do not materially adversely affect Tenant’s use of the Premises for the Permitted Use and provided that such modifications do not materially increase the obligations or materially decrease the rights of Tenant under this Lease.

     2. Delivery; Acceptance of Premises; Commencement Date. Landlord shall make the Premises available to Tenant for Tenant’s Work under the Work Letter within 2 days of full execution of this Lease and Tenant’s delivery of evidence of the insurance required hereby and by the Work Letter (“Delivery” or “Deliver”). As used herein, the term “Tenant’s Work” shall have the meaning set forth for such term in the Work Letter.

     The “Commencement Date” shall be the date Landlord Delivers the Premises to Tenant. The “Rent Commencement Date” shall be the earliest of: (i) the date the Tenant Improvements (as defined in the Work Letter) are Substantially Completed (as defined in the Work Letter) by Tenant; (ii) the date Tenant conducts any business in the Premises or any part thereof; and (iii) April 1, 2011 (“Outside Date”); provided, however, that the Outside Date shall be delayed one day for each day that Substantial Completion of the Tenant Improvements is delayed due to Landlord Delay (as defined in the Work Letter) and Force Majeure (as hereinafter defined). Upon request of Landlord, Tenant shall execute and deliver a written acknowledgment of the Commencement Date, the Rent Commencement Date and the expiration date of the Term when such are established in the form of the “Acknowledgement of Commencement Date” attached to this Lease as Exhibit D; provided, however, Tenant’s failure to execute and deliver such acknowledgment shall not affect Landlord’s rights hereunder. The “Term” of this Lease shall be the Base Term, as defined above on the first page of this Lease and any Extension Terms which Tenant may elect pursuant to Section 40 hereof.

     Except as set forth in this Lease or the Work Letter, if applicable: (i) Tenant shall accept the Premises in their condition as of the Commencement Date, subject to all applicable Legal Requirements (as defined in Section 7 hereof); (ii) Landlord shall have no obligation for any defects in the Premises; and (iii) Tenant’s taking possession of the Premises shall be conclusive evidence that Tenant accepts the Premises and that the Premises were in good condition at the time possession was taken. Any occupancy of the Premises by Tenant before the Commencement Date shall be subject to all of the terms and conditions of this Lease, except the obligation to pay Base Rent or Operating Expenses.

     Notwithstanding anything to the contrary contained herein, for the period of 90 consecutive days after the Commencement Date, Landlord shall, at its sole cost and expense (which shall not constitute an Operating Expense), be responsible for any repairs that are required to be made to the roof of and elevators in the Building, unless Tenant and/or any Tenant Party was responsible for the cause of such repair, in which case Tenant shall pay the cost.

     Tenant agrees and acknowledges that neither Landlord nor any agent of Landlord has made any representation or warranty with respect to the condition of all or any portion of the Premises or the Project, and/or the suitability of the Premises or the Project for the conduct of Tenant’s business, and Tenant waives any implied warranty that the Premises or the Project are suitable for the Permitted Use. This Lease constitutes the complete agreement of Landlord and Tenant with respect to the subject matter

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hereof and supersedes any and all prior representations, inducements, promises, agreements, understandings and negotiations which are not contained herein. Landlord in executing this Lease does so in reliance upon Tenant’s representations, warranties, acknowledgments and agreements contained herein.

     3. Rent.

     (a) Base Rent. The Base Rent for the month in which the Rent Commencement Date occurs and the Security Deposit shall be due and payable on delivery of an executed copy of this Lease to Landlord. Tenant shall pay to Landlord in advance, without demand, abatement, deduction or set-off, monthly installments of Base Rent on or before the first day of each calendar month during the Term hereof after the Rent Commencement Date, in lawful money of the United States of America, at the office of Landlord for payment of Rent set forth above, or to such other person or at such other place as Landlord may from time to time designate in writing. Payments of Base Rent for any fractional calendar month shall be prorated. The obligation of Tenant to pay Base Rent and other sums to Landlord and the obligations of Landlord under this Lease are independent obligations. Tenant shall have no right at any time to abate, reduce, or set-off any Rent (as defined in Section 5) due hereunder except for any abatement as expressly provided in this Lease.

     (b) Additional Rent. In addition to Base Rent, Tenant agrees to pay to Landlord as additional rent (“Additional Rent”): (i) Tenant’s Share of “Operating Expenses” (as defined in Section 5), and (ii) the TI Rent (as defined in Section 4), and (iii) any and all other amounts Tenant assumes or agrees to pay under the provisions of this Lease, including, without limitation, any and all other sums that may become due by reason of any default of Tenant or failure to comply with the agreements, terms, covenants and conditions of this Lease to be performed by Tenant, after any applicable notice and cure period.

     4. Base Rent Adjustments.

     (a) Additional Tenant Improvement Allowance. Landlord shall, subject to the terms of the Work Letter, make the Additional Tenant Improvement Allowance (as defined in the Work Letter) available to Tenant for the construction of the Tenant Improvements. Commencing on the Rent Commencement Date, and continuing thereafter monthly on the same day that Base Rent is due, in addition to Base Rent, Tenant agrees to pay to Landlord the amount necessary to fully amortize over the Base Term, the portion of the Additional Tenant Improvement Allowance actually funded by Landlord with interest at a rate of 8.5% per annum and paid in equal monthly installments (“TI Rent”). The Additional Tenant Improvement Allowance shall only be available for use by Tenant as part of the construction of the Tenant Improvements and Tenant shall have no right thereafter to use any undisbursed portion thereof.

     (b) Annual Adjustments. Base Rent shall be increased on each annual anniversary of the first day of the calendar month following the Rent Commencement Date (each an “Adjustment Date”) by multiplying the Base Rent payable immediately before such Adjustment Date by the Rent Adjustment Percentage and adding the resulting amount to the Base Rent payable immediately before such Adjustment Date. Base Rent, as so adjusted, shall thereafter be due as provided herein. Base Rent adjustments for any fractional calendar month shall be prorated.

     5. Operating Expense Payments. Landlord shall endeavor to deliver to Tenant, at least 30 days prior to the beginning of each calendar year of the Term, a written estimate of Operating Expenses for each calendar year during the Term (the “Annual Estimate”), which may be revised by Landlord from time to time during such calendar year but no more than quarterly. Commencing on the Rent Commencement Date and continuing thereafter on the first day of each month of the Term, Tenant shall pay Landlord an amount equal to 1/12th of Tenant’s Share of the Annual Estimate. Payments for any fractional calendar month shall be prorated.

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     The term “Operating Expenses” means all costs and expenses of any kind or description whatsoever incurred or accrued in accordance with GAAP (except as otherwise provided herein) each calendar year by Landlord with respect to the Building (including the Building’s Share of all costs and expenses of any kind or description incurred or accrued by Landlord with respect to the Project which are not specific to the Building or any other building located in the Project)(including, without duplication, Taxes (as defined in Section 9), capital repairs and improvements amortized over the useful life of such capital items as reasonably determined by Landlord taking into account relevant factors including, without limitation, the hours of operation of the Building and its use for laboratory/office purposes (“Approved Capital Expenses”), and the costs of Landlord’s third party property manager (not to exceed 1.5% of the then-current Base Rent for each month of the calendar year) or, if there is no third party property manager, administration rent in the amount of 1.5% of the then-current Base Rent for each month of the calendar year), excluding only:

     (a) the original construction costs of the Project and renovation prior to the date of the Lease and costs of correcting defects in such original construction or renovation;

     (b) expenditures for expansion of the Project, including to develop additional buildings at the Project;

     (c) any costs incurred to remove, study, test, remediate or otherwise related to the presence of Hazardous Materials in or about the Building or the Project, which Hazardous Materials Tenant proves (i) existed prior to the Commencement Date, except to the extent caused by or contributed to by Tenant or any Tenant Party, (ii) originated from any separately demised tenant space within the Project other than the Premises, except to the extent caused by or contributed to by Tenant or any Tenant Party, or (iii) were not brought upon, kept, used, stored, handled, treated, generated in, or released or disposed of from, the Project by Tenant or any Tenant Party (as herein defined);

     (d) interest, principal payments of Mortgage (as defined in Section 27) debts of Landlord, financing costs and amortization of funds borrowed by Landlord, whether secured or unsecured and all payments or base rent (but not taxes or operating expenses) under any ground lease or other underlying lease of all or any portion of the Project;

     (e) depreciation of the Project and reserves (except for capital improvements, the cost of which are includable in Operating Expenses);

     (f) advertising, legal and space planning expenses and leasing commissions and other costs and expenses incurred in procuring and leasing space to tenants for the Project, including any leasing office maintained in the Project, free rent and construction allowances for tenants;

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

     (h) completing, fixturing, improving, renovating, painting, redecorating or other work, which Landlord pays for or performs for other tenants within their premises, and costs of correcting defects in such work;

     (i) costs to be reimbursed by other tenants of the Project or Taxes to be paid directly by Tenant or other tenants of the Project, whether or not actually paid;

     (j) salaries, wages, benefits and other compensation paid to officers and employees of Landlord who are not assigned in whole or in part to the operation, management, maintenance or repair of the Project;

     (k) general organizational, administrative and overhead costs relating to maintaining Landlord’s existence, either as a corporation, partnership, or other entity, including general corporate, legal and accounting expenses;

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     (l) costs (including attorneys’ fees and costs of settlement, judgments and payments in lieu thereof) incurred in connection with disputes with tenants, other occupants, or prospective tenants, and costs and expenses, including legal fees, incurred in connection with negotiations or disputes with employees, consultants, management agents, leasing agents, purchasers or mortgagees of the Building;

     (m) costs incurred by Landlord due to the violation by Landlord, its employees, agents or contractors or any tenant of the terms and conditions of any lease of space in the Project or any Legal Requirement (as defined in Section 7);

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

     (o) overhead and profit increment paid to Landlord or to subsidiaries or affiliates of Landlord for goods and/or services in or to the Project to the extent the same exceeds the costs of such goods and/or services rendered by unaffiliated third parties on a competitive basis;

     (p) costs of Landlord’s charitable or political contributions, or of fine art maintained at the Project;

     (q) costs in connection with services (including electricity and janitorial), items or other benefits of a type which are not provided by Landlord to Tenant without specific charges therefor, but which are provided to another tenant or occupant of the Project, whether or not such other tenant or occupant is specifically charged therefor by Landlord;

     (r) costs incurred in the sale or refinancing of the Project;

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

     (t) any expenses otherwise includable within Operating Expenses to the extent actually reimbursed by persons other than tenants of the Project under leases for space in the Project;

     (u) costs incurred in connection with the operation of any parking concession within the Project;

     (v) costs incurred in connection with the performance of alterations or modifications to the Project (other than the Premises for which Tenant shall be solely responsible for) that are required solely due to the non-compliance of the Project with Legal Requirements applicable to the Project (other than the Premises for which Tenant shall be solely responsible for) as of the Commencement Date;

     (w) costs occasioned by condemnation; and

     (x) until the square footage of such buildings are included in the rentable area of the Project pursuant to the last paragraph of this Section 5, costs attributable to other portions of the Project other than Phase I as shown on the site plan attached hereto as Exhibit J.

     Notwithstanding anything to the contrary contained in this Lease, Tenant’s Share of each deductible affecting the Premises (as the same may be expanded pursuant to the terms of this Lease) or each uninsured casualty damage shall not exceed $12.00 per rentable square foot of the Premises (as the same may be expanded pursuant to the terms of this Lease) (the “Cap”). Commencing on the Rent Commencement Date and on the first day of each month thereafter, the Cap shall be reduced by $0.125 per rentable square foot of the Premises; provided, however, if the Term of the Lease is extended for any reason (e.g., Tenant extends for an Extension Term or the Term is extended pursuant to the provisions of

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Section 39(a)), then the Cap shall be increased on the commencement date of the applicable extension to an amount equal to the product of the number of years remaining on the Term multiplied by $1.20 per rentable square foot of the Premises and the same shall be reduced each month by $0.125 per rentable square foot of the Premises. Notwithstanding anything to the contrary contained in this paragraph in no event shall the Cap be reduced below $6.00 per rentable square foot of the Premises (as the same may be expanded pursuant to the terms of this Lease). Tenant shall pay Tenant’s Share of any such deductible or uninsured damage in equal monthly installments (not to exceed the applicable Cap) amortized over the remaining balance of the Base Term of this Lease (or, if the event occurs during an Extension Term, then over the remaining balance of such Extension Term) with interest at 8% per annum.

     Within 90 days after the end of each calendar year (or such longer period as may be reasonably required), Landlord shall furnish to Tenant a statement (an “Annual Statement”) showing in reasonable detail: (a) the total and Tenant’s Share of actual Operating Expenses for the previous calendar year, and (b) the total of Tenant’s payments in respect of Operating Expenses for such year. If Tenant’s Share of actual Operating Expenses for such year exceeds Tenant’s payments of Operating Expenses for such year, the excess shall be due and payable by Tenant as Rent within 30 days after delivery of such Annual Statement to Tenant. If Tenant’s payments of Operating Expenses for such year exceed Tenant’s Share of actual Operating Expenses for such year Landlord shall pay the excess to Tenant within 30 days after delivery of such Annual Statement, except that after the expiration, or earlier termination of the Term or if Tenant is delinquent in its obligation to pay Rent, Landlord shall pay the excess to Tenant after deducting all other amounts due Landlord.

     The Annual Statement shall be final and binding upon Tenant unless Tenant, within 60 days after Tenant’s receipt thereof, shall contest any item therein by giving written notice to Landlord, specifying each item contested and the reason therefor. If, during such 60 day period, Tenant reasonably and in good faith questions or contests the accuracy of Landlord’s statement of Tenant’s Share of Operating Expenses, Landlord will provide Tenant with access to Landlord’s books and records relating to the operation of the Project and such information as Landlord reasonably determines to be responsive to Tenant’s questions (the “Expense Information”). If after Tenant’s review of such Expense Information, Landlord and Tenant cannot agree upon the amount of Tenant’s Share of Operating Expenses, then Tenant shall have the right to have a nationally or regionally recognized independent public accounting firm selected by Tenant and approved by Landlord (which approval shall not be unreasonably withheld or delayed), working pursuant to a fee arrangement other than a contingent fee (at Tenant’s sole cost and expense), audit and/or review the Expense Information for the year in question (the “Independent Review”). The results of any such Independent Review shall be binding on Landlord and Tenant. If the Independent Review shows that the payments actually made by Tenant with respect to Operating Expenses for the calendar year in question exceeded Tenant’s Share of Operating Expenses for such calendar year, Landlord shall pay the excess to Tenant within 30 days after delivery of such statement, except that after the expiration or earlier termination of this Lease or if Tenant is delinquent in its obligation to pay Rent, Landlord shall pay the excess to Tenant after deducting all other amounts due Landlord. If the Independent Review shows that Tenant’s payments with respect to Operating Expenses for such calendar year were less than Tenant’s Share of Operating Expenses for the calendar year, Tenant shall pay the deficiency to Landlord within 30 days after delivery of such statement. If the Independent Review shows that Tenant has overpaid with respect to Operating Expenses by more than 5% then Landlord shall reimburse Tenant for all costs incurred by Tenant for the Independent Review. Operating Expenses for the calendar years in which Tenant’s obligation to share therein begins and ends shall be prorated such that Tenant shall not be required to pay any Taxes or other Operating Expenses for periods prior to the Rent Commencement Date or after the termination of this Lease.

     “Tenant’s Share” shall be the percentage set forth on the first page of this Lease as Tenant’s Share as reasonably adjusted by Landlord for changes in the physical size of the Premises or the Project occurring thereafter. The rentable area of the Premises shall not be subject to remeasurement by either party. If Landlord has a reasonable basis for doing so, Landlord may equitably charge Tenant for any item of expense or cost reimbursable by Tenant that relates to a repair, replacement, or service that benefits only the Premises or only a portion of the Project that includes the Premises or that varies with

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occupancy or use. Base Rent, Tenant’s Share of Operating Expenses and all other amounts payable by Tenant to Landlord hereunder are collectively referred to herein as “Rent.”

     Landlord and Tenant acknowledge that Landlord intends to develop other buildings at the Project. Upon receipt of a temporary or permanent certificate of occupancy for each new building at the Project, (x) the definition of “Rentable Area of Project” on page 1 of this Lease shall be amended as to reflect the actual rentable square footage of such buildings, and (y) the definitions of “Building’s Share of Project” and “Tenant’s Share of Operating Expenses of Project” on page 1 of this Lease shall also be amended due to the fact that the same were calculated based on the actual rentable square footage of the Building and the Project as of the date of this Lease.

     6. Security Deposit. Tenant shall deposit with Landlord, upon delivery of an executed copy of this Lease to Landlord, a security deposit (the “Security Deposit”) for the performance of all of Tenant’s obligations hereunder in the amount set forth on page 1 of this Lease, which Security Deposit shall be in the form of an unconditional and irrevocable letter of credit (the “Letter of Credit”): (i) in form and substance satisfactory to Landlord, (ii) naming Landlord as beneficiary, (iii) expressly allowing Landlord to draw upon it at any time from time to time by delivering to the issuer notice that Landlord is entitled to draw thereunder, (iv) issued by an FDIC-insured financial institution satisfactory to Landlord, and (v) redeemable by presentation of a sight draft in the state of Landlord’s choice. If Tenant does not provide Landlord with a substitute Letter of Credit complying with all of the requirements hereof at least 10 days before the stated expiration date of any then current Letter of Credit, Landlord shall have the right to draw the full amount of the current Letter of Credit and hold the funds drawn in cash without obligation for interest thereon as the Security Deposit until Tenant shall have replaced the expired Letter of Credit with a new Letter of Credit consistent with the requirements herein, at which time Landlord shall refund the amount of the previously drawn Letter of Credit to Tenant less any amounts applied under this Lease. The Security Deposit shall be held by Landlord as security for the performance of Tenant’s obligations under this Lease. The Security Deposit is not an advance rental deposit or a measure of Landlord’s damages in case of Tenant’s default. Upon each occurrence of a Default (as defined in Section 20), Landlord may use all or any part of the Security Deposit to pay delinquent payments due under this Lease, future rent damages under California Civil Code Section 1951.2, and the cost of any damage, injury, expense or liability caused by such Default, without prejudice to any other remedy provided herein or provided by law. Landlord’s right to use the Security Deposit under this Section 6 includes the right to use the Security Deposit to pay future rent damages following the termination of this Lease pursuant to Section 21(c) below. Upon any use of all or any portion of the Security Deposit, Tenant shall, at Landlord’s option, (i) pay Landlord on demand the amount that will restore the Security Deposit to the amount set forth on Page 1 of this Lease or (ii) restore the Letter of Credit to the amount defined herein. Tenant hereby waives the provisions of any law, now or hereafter in force, including, without limitation, California Civil Code Section 1950.7, which provide that Landlord may claim from a security deposit only those sums reasonably necessary to remedy defaults in the payment of Rent, to repair damage caused by Tenant or to clean the Premises, it being agreed that Landlord may, in addition, claim those sums reasonably necessary to compensate Landlord for any other loss or damage, foreseeable or unforeseeable, caused by the act or omission of Tenant or any officer, employee, agent or invitee of Tenant. Upon bankruptcy or other debtor-creditor proceedings against Tenant, the Security Deposit shall be deemed to be applied first to the payment of Rent and other charges due Landlord for periods prior to the filing of such proceedings. Upon any such use of all or any portion of the Security Deposit, Tenant shall, within 5 days after demand from Landlord, restore the Security Deposit to its original amount. If Tenant shall fully perform every provision of this Lease to be performed by Tenant, the Security Deposit, or any balance thereof (i.e., after deducting therefrom all amounts to which Landlord is entitled under the provisions of this Lease), shall be returned to Tenant (or, at Landlord’s option, to the last assignee of Tenant’s interest hereunder) within 90 days after the expiration or earlier termination of this Lease.

     If Landlord transfers its interest in the Project or this Lease, Landlord shall either (a) transfer any Security Deposit then held by Landlord to a person or entity assuming Landlord’s obligations under this Section 6, or (b) return to Tenant any Security Deposit then held by Landlord and remaining after the deductions permitted herein. Upon such transfer to such transferee or the return of the Security Deposit

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to Tenant, Landlord shall have no further obligation with respect to the Security Deposit, and Tenant’s right to the return of the Security Deposit shall apply solely against Landlord’s transferee. Landlord’s obligation respecting the Security Deposit is that of a debtor, not a trustee, and no interest shall accrue thereon.

     7. Use. The Premises shall be used solely for the Permitted Use set forth in the basic lease provisions on page 1 of this Lease, and in compliance with all laws, orders, judgments, ordinances, regulations, codes, directives, permits, licenses, covenants and restrictions now or hereafter applicable to the Premises, and to the use and occupancy thereof, including, without limitation, the Americans With Disabilities Act, 42 U.S.C. § 12101, et seq. (together with the regulations promulgated pursuant thereto, “ADA”) (collectively, “Legal Requirements” and each, a “Legal Requirement”). Tenant shall, as quickly as commercially feasible following written notice from Landlord, discontinue any use of the Premises which is declared by any Governmental Authority (as defined in Section 9) having jurisdiction to be a violation of a Legal Requirement. Tenant will not use or permit the Premises to be used for any purpose or in any manner that would void Tenant’s or Landlord’s insurance or cause the disallowance of any sprinkler or other credits. The Permitted Use as defined in this Lease will not result in the voidance of or an increased insurance risk or cause the disallowance of any sprinkler or other credits with respect to the insurance currently being maintained by Landlord. Tenant shall not permit any part of the Premises to be used as a “place of public accommodation”, as defined in the ADA or any similar legal requirement. Tenant shall reimburse Landlord promptly upon demand for any additional premium charged for any such insurance policy by reason of Tenant’s failure to comply with the provisions of this Section or otherwise caused by Tenant’s use and/or occupancy of the Premises. Tenant will use the Premises in a careful, safe and proper manner and will not commit or permit waste, overload the floor or structure of the Premises, subject the Premises to use that would damage the Premises or obstruct or interfere with the rights of Landlord or other tenants or occupants of the Project, including conducting or giving notice of any auction, liquidation, or going out of business sale on the Premises, or using or allowing the Premises to be used for any unlawful purpose. Tenant shall cause any equipment or machinery to be installed in the Premises so as to reasonably prevent sounds or vibrations from the Premises from extending into Common Areas, or other space in the Project. Tenant shall not place any machinery or equipment which will overload the floor in or upon the Premises or transport or move such items through the Common Areas of the Project or in the Project elevators without the prior written consent of Landlord. Except as may be provided under the Work Letter, Tenant shall not, without the prior written consent of Landlord, which shall not be unreasonably withheld or delayed, use the Premises in any manner which will require ventilation, air exchange, heating, gas, steam, electricity or water beyond the existing capacity of the Project as proportionately allocated to the Premises based upon Tenant’s Share as usually furnished for the Permitted Use.

     Landlord shall, as an Operating Expense (to the extent such Legal Requirement is generally applicable to similar buildings in the area in which the Project is located) or at Tenant’s expense (to the extent such Legal Requirement is applicable by reason of Tenant’s, as compared to other tenants of the Project, particular use of the Premises or any alterations or modifications or Tenant Improvements made by Tenant) make any alterations or modifications to the Project that are required by Legal Requirements, including the ADA. However, Tenant shall, at Tenant’s expense, make any alterations or modifications to the Premises that are required due to the non compliance of the Premises with the Legal Requirements applicable to the Premises as of the Commencement Date. Notwithstanding any other provision herein to the contrary, subject to the first sentence of this paragraph, Tenant shall be responsible for any and all demands, claims, liabilities, losses, costs, expenses, actions, causes of action, damages or judgments, and all reasonable expenses incurred in investigating or resisting the same (including, without limitation, reasonable attorneys’ fees, charges and disbursements and costs of suit) (collectively, “Claims”) arising out of any failure of the Premises to comply with any Legal Requirements, and Tenant shall indemnify, defend, hold and save Landlord harmless from and against any and all Claims arising out of or in connection with any failure of the Premises to comply with any Legal Requirement.

     8. Holding Over. If, with Landlord’s express written consent, Tenant retains possession of the Premises after the termination of the Term, (i) unless otherwise agreed in such written consent, such

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possession shall be subject to immediate termination by Landlord at any time, (ii) all of the other terms and provisions of this Lease (including, without limitation, the adjustment of Base Rent pursuant to Section 4 hereof) shall remain in full force and effect (excluding any expansion or renewal option or other similar right or option) during such holdover period, (iii) Tenant shall continue to pay Base Rent in the amount payable upon the date of the expiration or earlier termination of this Lease or such other amount as Landlord may indicate, in Landlord’s sole and absolute discretion, in such written consent, and (iv) all other payments shall continue under the terms of this Lease. If Tenant remains in possession of the Premises after the expiration or earlier termination of the Term without the express written consent of Landlord, (A) Tenant shall become a tenant at sufferance upon the terms of this Lease except that the monthly rental shall be equal to 150% of Rent in effect during the last 30 days of the Term for the first 60 days of such tenancy at sufferance and thereafter 200% of Rent in effect during the last 30 days of the Term, and (B) Tenant shall be responsible for all damages suffered by Landlord resulting from or occasioned by Tenant’s holding over, including consequential damages. No holding over by Tenant, whether with or without consent of Landlord, shall operate to extend this Lease except as otherwise expressly provided, and this Section 8 shall not be construed as consent for Tenant to retain possession of the Premises. Acceptance by Landlord of Rent after the expiration of the Term or earlier termination of this Lease shall not result in a renewal or reinstatement of this Lease.

     9. Taxes. Landlord shall pay, as part of Operating Expenses, all taxes, levies, fees, assessments and governmental charges of any kind, existing as of the Commencement Date or thereafter enacted (collectively referred to as “Taxes”), imposed by any federal, state, regional, municipal, local or other governmental authority or agency, including, without limitation, quasi-public agencies (collectively, “Governmental Authority”) during the Term, including, without limitation, all Taxes: (i) imposed on or measured by or based, in whole or in part, on rent payable to (or gross receipts received by) Landlord under this Lease and/or from the rental by Landlord of the Project or any portion thereof, or (ii) based on the square footage, assessed value or other measure or evaluation of any kind of the Premises or the Project, or (iii) assessed or imposed by or on the operation or maintenance of any portion of the Premises or the Project, including parking, or (iv) assessed or imposed by, or at the direction of, or resulting from Legal Requirements, or interpretations thereof, promulgated by any Governmental Authority, or (v) imposed as a license or other fee, charge, tax, or assessment on Landlord’s business or occupation of leasing space in the Project. Landlord may contest by appropriate legal proceedings the amount, validity, or application of any Taxes or liens securing Taxes. Notwithstanding anything to the contrary herein, Landlord shall only charge Tenant for assessments as if those assessments were paid by Landlord over the longest possible term which Landlord is permitted to pay for the applicable assessments without additional charge other than interest, if any, provided under the terms of the underlying assessments. Notwithstanding anything to the contrary contained in this Lease, Taxes shall not include any net income taxes, gross receipts tax, estate taxes or inheritance taxes imposed on Landlord except to the extent such net income taxes are in substitution for any Taxes payable hereunder, or any late penalties, interest or fines unless due to any late payment of Rent by Tenant. If any such Tax is levied or assessed directly against Tenant, then Tenant shall be responsible for and shall pay the same at such times and in such manner as the taxing authority shall require. Tenant shall pay, prior to delinquency, any and all Taxes levied or assessed against any personal property or trade fixtures placed by Tenant in the Premises, whether levied or assessed against Landlord or Tenant. If any Taxes on Tenant’s personal property or trade fixtures are levied against Landlord or Landlord’s property, or if the assessed valuation of the Project is increased by a value attributable to improvements in or alterations to the Premises, whether owned by Landlord or Tenant and whether or not affixed to the real property so as to become a part thereof, higher than the base valuation on which Landlord from time-to-time allocates Taxes to all tenants in the Project, Landlord shall have the right, but not the obligation, to pay such Taxes. Landlord’s determination of any excess assessed valuation shall be binding and conclusive, absent manifest error. The amount of any such payment by Landlord shall constitute Additional Rent due from Tenant to Landlord immediately upon demand.

     10. Parking. Subject to all matters of record, Force Majeure, a Taking (as defined in Section 19 below) and the exercise by Landlord of its rights hereunder, Tenant shall have the right, in common with other tenants of the Project pro rata in accordance with the rentable area of the Premises and the

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rentable areas of the Project occupied by such other tenants, to park in those areas designated for non-reserved parking, subject in each case to Landlord’s rules and regulations. Subject to the foregoing, Tenant’s pro rata share of parking shall not be less than 2.83 parking spaces per 1,000 rentable square feet of the Premises. Landlord may reasonably designate (taking into consideration the proximity of such spaces to the leased premises) certain parking spaces within the Project for the exclusive use of Tenant and other tenants in the Project on a pro rata basis as described above if Landlord determines that such parking facilities are becoming crowded.

     11. Utilities, Services. Landlord shall provide, subject to the terms of this Section 11, water, electricity, heat, light, power, sewer, and other utilities (including gas and fire sprinklers to the extent the Project is plumbed for such services), refuse and trash collection and, to the Common Areas, janitorial services (collectively, “Utilities”). Landlord shall pay, as Operating Expenses or subject to Tenant’s reimbursement obligation, for all Utilities used on the Premises, all maintenance charges for Utilities, and any storm sewer charges or other similar charges for Utilities imposed by any Governmental Authority or Utility provider, and any taxes, penalties, surcharges or similar charges thereon. Landlord may cause, at Landlord’s expense, any Utilities to be separately metered or charged directly to Tenant by the provider. Tenant shall pay directly to the Utility provider, prior to delinquency, any separately metered Utilities and services which may be furnished to Tenant or the Premises during the Term. Tenant shall pay, as part of Operating Expenses, its share of all charges for jointly metered Utilities based upon consumption, as reasonably determined by Landlord. No interruption or failure of Utilities, from any cause whatsoever other than Landlord’s willful misconduct, shall result in eviction or constructive eviction of Tenant, termination of this Lease or the abatement of Rent.

     12. Alterations and Tenant’s Property. Any alterations, additions, or improvements made to the Premises by or on behalf of Tenant, including additional locks or bolts of any kind or nature upon any doors or windows in the Premises, but excluding installation, removal or realignment of furniture systems (other than removal of furniture systems owned or paid for by Landlord) not involving any modifications to the structure or connections (other then by ordinary plugs or jacks) to Building Systems (as defined in Section 13) (“Alterations”) shall be subject to Landlord’s prior written consent, which shall not be unreasonably withheld. Tenant may construct nonstructural Alterations in the Premises from time to time without Landlord’s prior approval if the cost of the applicable project does not exceed $100,000 (a “Notice-Only Alteration”), provided Tenant notifies Landlord in writing (or by email to persons designated by Landlord from time to time as Landlord’s representatives for purposes of receiving such email notices) of such intended Notice-Only Alteration. For all other Alterations, Tenant’s notice shall be accompanied by plans, specifications, work contracts and such other information concerning the nature and cost of the Notice-Only Alteration as may be reasonably requested by Landlord, which notice and accompanying materials shall be delivered to Landlord not less than 15 business days in advance of any proposed construction. If Landlord approves any Alterations, Landlord may impose such conditions on Tenant in connection with the commencement, performance and completion of such Alterations as Landlord may deem appropriate in Landlord’s reasonable discretion and the procedures set forth in Sections 2(a) — 2(d), 3(a) and 4 of the Work Letter shall apply to the approval of the plans and construction but with Tenant being responsible for all costs. Any request for approval shall be in writing, delivered not less than 15 business days in advance of any proposed construction, and accompanied by plans, specifications, bid proposals, work contracts and such other information concerning the nature and cost of the alterations as may be reasonably requested by Landlord, including the identities and mailing addresses of all persons performing work or supplying materials. Landlord’s right to review plans and specifications and to monitor construction shall be solely for its own benefit, and Landlord shall have no duty to ensure that such plans and specifications or construction comply with applicable Legal Requirements. Tenant shall cause, at its sole cost and expense, all Alterations to comply with insurance requirements and with Legal Requirements and shall implement at its sole cost and expense any alteration or modification required by Legal Requirements as a result of any Alterations. Tenant shall pay to Landlord, as Additional Rent, on demand an amount equal to 1.5% of all charges incurred by Tenant or its contractors or agents in connection with any Alteration as to which Landlord’s consent is required to cover Landlord’s overhead and expenses where Landlord has plan review, coordination, scheduling and supervision responsibilities (albeit along with Tenant) in connection with such Alteration. Notwithstanding the foregoing, Tenant shall

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not be required to pay the Additional Rent provided for in the preceding sentence for an Alteration where Landlord’s obligations are limited to review and approval of plans for the proposed Alteration. Before Tenant begins any Alteration, Landlord may post on and about the Premises notices of non-responsibility pursuant to applicable law. Tenant shall reimburse Landlord for, and indemnify and hold Landlord harmless from, any expense incurred by Landlord by reason of faulty work done by Tenant or its contractors, delays caused by such work, or inadequate cleanup. Notwithstanding anything to the contrary contained herein, if any of Tenant’s Alterations result in the configuration between laboratory and office space on the first and second floors of the Building being other than what is in place immediately following the completion of construction of the Tenant Improvements; and if any proposed Alterations would reduce the proportion of laboratory to office space, then in addition to requiring the restoration of the same upon the expiration or earlier termination of the Term, Landlord shall have the right, if the restoration cost is reasonably determined by Landlord to be material, to require Tenant to concurrently deposit with Landlord a letter of credit in an amount not to exceed the estimated restoration cost to secure Tenant’s restoration obligation. Such letter of credit shall be in form and content reasonably acceptable to Landlord and otherwise satisfy the requirements of Section 6.

     Tenant shall furnish security or make other arrangements reasonably satisfactory to Landlord to assure payment for the completion of all Alterations costing in excess of $500,000 free and clear of liens, and shall provide (and cause each contractor or subcontractor to provide) certificates of insurance for workers’ compensation and other coverage in amounts and from an insurance company satisfactory to Landlord protecting Landlord against liability for personal injury or property damage during construction. Upon completion of any Alterations, Tenant shall deliver to Landlord: (i) sworn statements setting forth the names of all contractors and subcontractors who did the work and final lien waivers from all such contractors and subcontractors; and (ii) “as built” plans for any such Alteration.

     Except for Removable Installations (as hereinafter defined), all Installations (as hereinafter defined) shall be and shall remain the property of Landlord during the Term and following the expiration or earlier termination of the Term, shall not be removed by Tenant at any time during the Term, and shall remain upon and be surrendered with the Premises as a part thereof. Notwithstanding the foregoing, Landlord may, at the time its approval of any such Installation is requested, notify Tenant that Landlord requires that Tenant remove such Installation upon the expiration or earlier termination of the Term, in which event Tenant shall remove such Installation in accordance with the immediately succeeding sentence. Upon the expiration or earlier termination of the Term, Tenant shall remove (i) all wires, cables or similar equipment which Tenant has installed in the Premises or in the risers or plenums of the Building, (ii) any Installations for which Landlord has given Tenant notice of removal in accordance with the immediately preceding sentence, and (iii) all of Tenant’s Property (as hereinafter defined), and Tenant shall restore and repair any damage caused by or occasioned as a result of such removal, including, without limitation, capping off all such connections behind the walls of the Premises and repairing any holes. During any restoration period beyond the expiration or earlier termination of the Term, Tenant shall pay Rent to Landlord as provided herein as if said space were otherwise occupied by Tenant. Notwithstanding anything to the contrary contained herein, Tenant shall have no obligation to remove any Tenant Improvements. If Landlord is requested by Tenant or any lender, lessor or other person or entity claiming an interest in any of Tenant’s Property to waive any lien Landlord may have against any of Tenant’s Property, and Landlord consents to such waiver, then Landlord shall be entitled to be paid as administrative rent a fee of $1,000 per occurrence for its time and effort in preparing and negotiating such a waiver of lien.

     For purposes of this Lease, (x) “Removable installations” means any items listed on Exhibit F attached hereto and any items agreed by Landlord in writing to be included on Exhibit F in the future, (y) “Tenant’s Property” means Removable Installations and, other than Installations, any personal property or equipment of Tenant that may be removed without material damage to the Premises, and (z) “Installations” means all property of any kind paid for by Landlord, all Alterations, all fixtures, and all partitions, hardware, built-in machinery, built-in casework and cabinets and other similar additions, equipment, property and improvements built into the Premises so as to become an integral part of the Premises, including, without limitation, fume hoods which penetrate the roof or plenum area, built-in cold

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rooms, built-in warm rooms, walk-in cold rooms, walk-in warm rooms, deionized water systems, glass washing equipment, autoclaves, chillers, built-in plumbing, electrical and mechanical equipment and systems, and any power generator and transfer switch.

     13. Landlord’s Repairs. Landlord, as an Operating Expense (except to the extent the cost thereof is excluded from Operating Expenses pursuant to Section 5 hereof), shall maintain all of the structural, exterior, parking and other Common Areas of the Project, including HVAC, plumbing, fire sprinklers, fire risers, elevators and all other building systems serving the Premises and other portions of the Project and related utilities beyond the meters (“Building Systems”), in good repair, reasonable wear and tear and uninsured losses and damages (unless such losses or damages would have been insured losses or expenses if the insurance Landlord is required to maintain hereunder had been obtained) caused by Tenant, or by any of Tenant’s agents, servants, employees, invitees and contractors (collectively, “Tenant Parties”) excluded. Subject to the provisions of the penultimate paragraph of Section 17, losses and damages caused by Tenant or any Tenant Party shall be repaired by Landlord, at Tenant’s sole cost and expense, to the extent not covered by insurance Landlord is required to maintain hereunder (or to the extent such losses or damages would have been covered by insurance Landlord is required to maintain hereunder if such insurance had been maintained and so long as it would make reasonable business sense to Landlord unless the losses or damages in question are relatively minor, bearing in mind the potential amount of the losses and damages and the amount of the applicable deductibles, to submit a claim for such losses and damages to its insurer). Landlord reserves the right to stop Building Systems services when necessary (i) by reason of accident or emergency, or (ii) for planned repairs, alterations or improvements, which are, in the judgment of Landlord, desirable or necessary to be made, until said repairs, alterations or improvements shall have been completed, provided Landlord shall use reasonable efforts to minimize interference with Tenant’s Permitted Use of the Premises. Landlord shall have no responsibility or liability for failure to supply Building Systems services during any such period of interruption; provided, however, that Landlord shall, except in case of emergency, make a commercially reasonable effort to give Tenant 24 hours advance notice of any planned stoppage of Building Systems services for routine maintenance, repairs, alterations or improvements and shall in all events use reasonable efforts to perform any repairs in a manner that will minimize interference and Tenant’s use of the Premises. Tenant shall promptly give Landlord written notice of any repair required by Landlord pursuant to this Section, after which Landlord shall make a commercially reasonable effort to effect such repair. Landlord shall not be liable for any failure to make any repairs or to perform any maintenance unless such failure shall persist for an unreasonable time after Tenant’s written notice of the need for such repairs or maintenance as provided in this Lease. Tenant waives its rights under any state or local law to terminate this Lease or to make such repairs at Landlord’s expense and agrees that the parties’ respective rights with respect to such matters shall be solely as set forth herein. Repairs required as the result of fire, earthquake, flood, vandalism, war, or similar cause of damage or destruction shall be controlled by Section 18.

     Notwithstanding the foregoing, during any period that Tenant is leasing the Premises and all of the Additional Space, Tenant may access the Building’s environmental management system to directly control its own utilities and shall have the obligation to maintain, at Tenant’s sole cost and expense, all of Building Systems which serve the Building except for the elevators, fire risers and utilities beyond the meters which shall be maintained by Landlord as part of Operating Expenses. The maintenance obligation described in the preceding sentence shall include, without limitation, an obligation on the part of Tenant to maintain the applicable Building Systems in good condition and repair which shall include the procurement and maintenance of contracts, in form and substance reasonably satisfactory to Landlord, with copies to Landlord, for, and with contractors specializing and experienced in the maintenance and repair of such Building Systems that Tenant is responsible for under this Lease. If Tenant fails to maintain such Building Systems in a manner reasonably acceptable to Landlord, Landlord shall have the right to provide Tenant with written notice thereof and to undertake maintenance of such Building Systems if Tenant does not cure Tenant’s failure within 10 days after receipt of such notice.

     14. Tenant’s Repairs. Subject to Section 13 hereof, Tenant, at its expense, shall repair, replace and maintain in good condition all portions of the Premises, including, without limitation, entries,

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doors, ceilings, interior windows, interior walls, and the interior side of demising walls, including systems serving the Premises. Such repair and replacement may include capital expenditures and repairs whose benefit may extend beyond the Term. Should Tenant fail to make any such repair or replacement or fail to maintain the Premises, Landlord shall give Tenant notice of such failure. If Tenant fails to commence cure of such failure within 10 days of Landlord’s notice, and thereafter diligently prosecute such cure to completion, Landlord may perform such work and shall be reimbursed by Tenant within 10 days after demand therefor; provided, however, that if such failure by Tenant creates or could create an emergency, Landlord may immediately commence cure of such failure and shall thereafter be entitled to recover the costs of such cure from Tenant. Subject to Sections 17 and 18, Tenant shall bear the full uninsured cost of any repair or replacement to any part of the Project that results from damage caused by Tenant or any Tenant Party and any repair that benefits only the Premises.

     15. Mechanic’s Liens. Tenant shall discharge, by bond or otherwise, any mechanic’s lien filed against the Premises or against the Project for work claimed to have been done for, or materials claimed to have been furnished to, Tenant within 10 days after the filing thereof, at Tenant’s sole cost and shall otherwise keep the Premises and the Project free from any liens arising out of work performed, materials furnished or obligations incurred by Tenant. Should Tenant fail to discharge any lien described herein, Landlord shall have the right, but not the obligation, to pay such claim or post a bond or otherwise provide security to eliminate the lien as a claim against title to the Project and the cost thereof shall be immediately due from Tenant as Additional Rent. If Tenant shall lease or finance the acquisition of office equipment, furnishings, or other personal property of a removable nature utilized by Tenant in the operation of Tenant’s business, Tenant warrants that any Uniform Commercial Code Financing Statement filed as a matter of public record by any lessor or creditor of Tenant will upon its face or by exhibit thereto indicate that such Financing Statement is applicable only to removable personal property of Tenant located within the Premises. In no event shall the address of the Project be furnished on the statement without qualifying language as to applicability of the lien only to removable personal property, located in an identified suite held by Tenant.

     16. Indemnification. Tenant hereby indemnifies and agrees to defend, save and hold Landlord harmless from and against any and all Claims for injury or death to persons or damage to property occurring within or about the Premises, arising directly or indirectly out of use or occupancy of the Premises or a breach or default by Tenant in the performance of any of its obligations hereunder, except to the extent caused by the willful misconduct or negligence of Landlord or the default by Landlord in the performance of its obligations under this Lease. Landlord shall not be liable to Tenant for, and Tenant assumes all risk of damage to, personal property (including, without limitation, loss of records kept within the Premises). Tenant further waives any and all Claims for injury to Tenant’s business or loss of income relating to any such damage or destruction of personal property (including, without limitation, any loss of records). Landlord shall not be liable for any damages arising from any act, omission or neglect of any tenant in the Project or of any other third party.

     17. Insurance. Landlord shall maintain all risk property and, if applicable, sprinkler damage insurance covering the full replacement cost of the Project including the Tenant Improvements. Landlord shall further procure and maintain commercial general liability insurance with a single loss limit of not less than $3,000,000 for bodily injury and property damage with respect to the Project. Landlord may, but is not obligated to, maintain such other insurance and additional coverages as it may deem necessary, including, but not limited to, flood, environmental hazard and earthquake, loss or failure of building equipment, errors and omissions, rental loss during the period of repair or rebuilding, workers’ compensation insurance and fidelity bonds for employees employed to perform services and insurance for any improvements installed by Tenant or which are in addition to the standard improvements customarily furnished by Landlord without regard to whether or not such are made a part of the Project. All such insurance shall be included as part of the Operating Expenses. The Project may be included in a blanket policy (in which case the cost of such insurance allocable to the Project will be determined by Landlord based upon the insurer’s cost calculations). Tenant shall also reimburse Landlord for any increased premiums or additional insurance which Landlord reasonably deems necessary as a result of Tenant’s use of the Premises.

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

     In each instance where insurance is to name Landlord as an additional insured, Tenant shall upon written request of Landlord also designate and furnish certificates so evidencing Landlord as additional insured to: (i) any lender of Landlord holding a security interest in the Project or any portion thereof, (ii) the landlord under any lease wherein Landlord is tenant of the real property on which the Project is located, if the interest of Landlord is or shall become that of a tenant under a ground or other underlying lease rather than that of a fee owner, and/or (iii) any management company retained by Landlord to manage the Project.

     The property insurance obtained by Landlord and Tenant shall include a waiver of subrogation by the insurers and all rights based upon an assignment from its insured, against Landlord or Tenant, and their respective officers, directors, employees, managers, agents, invitees and contractors (“Related Parties”), in connection with any loss or damage thereby insured against. Notwithstanding anything to the contrary contained in this Lease, neither party nor its respective Related Parties shall be liable to the other for loss or damage caused by any risk insured against under property insurance required to be maintained hereunder regardless of the negligence of the party to the Lease receiving the benefit of the waiver, and each party waives any claims against the other party, and its respective Related Parties, for such loss or damage. The failure of a party to insure its property shall not void this waiver. Landlord and its respective Related Parties shall not be liable for, and Tenant hereby waives all claims against such parties for, business interruption and losses occasioned thereby sustained by Tenant or any person claiming through Tenant resulting from any accident or occurrence in or upon the Premises or the Project from any cause whatsoever. If the foregoing waivers shall contravene any law with respect to exculpatory agreements, the liability of Landlord or Tenant shall be deemed not released but shall be secondary to the other’s insurer.

     Landlord may require insurance policy limits to be raised to conform with requirements of Landlord’s lender and/or to bring coverage limits to levels then being generally required of new tenants within the Project; provided, however, that the increased amount of coverage is consistent with coverage amounts then being required by institutional owners of similar projects with tenants occupying similar size premises in the geographical area in which the Project is located.

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

     Notwithstanding the foregoing, Landlord shall also have the right to terminate this Lease if sufficient insurance proceeds are not available to pay for such restoration in full but not in the event that sufficient insurance proceeds are not available as a result of Landlord’s failure to maintain the property insurance which Landlord is expressly required to maintain under this Lease. Notwithstanding the foregoing, if the Building is damaged or destroyed by a casualty which is not covered by Landlord’s insurance (or is only partially covered by Landlord’s insurance) such that any shortfall in coverage to restore the Building is (i) 5% or less of the replacement cost of the Building, Landlord shall be required to repair the Building (exclusive of Tenant’s Property and Alterations), or (ii) more than 5% of the replacement cost of the Building and Landlord is not willing to pay for the cost of the repair, then Landlord shall give written notice to Tenant of such determination (the “Determination Notice”). In addition, if any Holder requires that any of the insurance proceeds from a casualty be applied to indebtedness secured by the Project and it results in a shortfall of more than 5% of the replacement cost of the Building to complete the repairs and Landlord is not willing to pay for such shortfall, then Landlord shall have the right to provide a Determination Notice to Tenant. Either Landlord or Tenant may terminate this Lease by giving written notice (“Termination Notice”) to the other party within 30 days after receipt of the Determination Notice. Tenant shall have the right to reject Landlord’s termination notice and require Landlord to restore the Building provided, however, that Tenant provides Landlord with written notice (“Termination Rejection Notice”), within 10 business days after receipt of the Termination Notice, of Tenant’s election to require Landlord to restore the Building and Tenant pays the full amount of the shortfall over and above the 5% that Landlord would have been required to pay (“Tenant Contribution”). Landlord shall have the right to require Tenant to deposit a letter of credit complying with the terms of Section 6 above in the amount of the full Tenant Contribution with Landlord concurrently with Tenant’s delivery of the Termination Rejection Notice to secure Tenant’s obligation to pay the Tenant Contribution. Notwithstanding anything to the contrary contained in this paragraph, (w) if the shortfall which is required

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to be paid by Landlord is greater than 3% but not more than 5% of the replacement cost of the Building, Landlord shall have no obligation to make any repairs under this paragraph unless there is at least 7 years remaining on the Base Term of this Lease from and after the estimated completion date of the repairs, (x) if the shortfall which is required to be paid by Landlord is greater than 1% but not more than 3% of the replacement cost of the Building, Landlord shall have no obligation to make any repairs under this paragraph unless there is at least 2 years remaining on the Base Term of this Lease (or, if applicable, an Extension Term) from and after the estimated completion date of the repairs, and (y) if the shortfall which is required to be paid by Landlord is 1% or less of the replacement cost of the Building, Landlord shall be required to complete the repairs unless any provisions of this Lease other than this paragraph may apply.

     Tenant may, at Tenant’s option, promptly re-enter the Premises and commence doing business in accordance with this Lease upon Landlord’s completion of all repairs or restoration required to be done by Landlord pursuant to this Section 18; provided, however, that Tenant shall nonetheless (and even if Tenant does not re-enter the Premises) continue to be responsible for all of its obligations under this Lease. Rent shall be abated from the date all required Hazardous Material Clearances applicable to Tenant’s operations at the Premises are obtained until the Premises are repaired and restored, in the proportion which the area of the Premises, if any, which is not usable by Tenant bears to the total area of the Premises. Such abatement shall be the sole remedy of Tenant, and except as provided in this Section 18, Tenant waives any right to terminate the Lease by reason of damage or casualty loss.

     The provisions of this Lease, including this Section 18, constitute an express agreement between Landlord and Tenant with respect to any and all damage to, or destruction of, all or any part of the Premises, or any other portion of the Project, and any statute or regulation which is now or may hereafter be in effect shall have no application to this Lease or any damage or destruction to all or any part of the Premises or any other portion of the Project, the parties hereto expressly agreeing that this Section 18 sets forth their entire understanding and agreement with respect to such matters.

     19. Condemnation. If the whole or any material part of the Premises or the Building is taken for any public or quasi-public use under governmental law, ordinance, or regulation, or by right of eminent domain, or by private purchase in lieu thereof (a “Taking” or “Taken”), and the Taking would in Landlord’s reasonable judgment, either prevent or materially interfere with Tenant’s use of the Premises or materially interfere with or impair Landlord’s ownership or operation of the Project, then upon written notice by Landlord this Lease shall terminate and Rent shall be apportioned as of said date. If part of the Premises shall be Taken, and this Lease is not terminated as provided above, Landlord shall promptly restore the Premises and the Project as nearly as is commercially reasonable under the circumstances to their condition prior to such partial Taking and the rentable square footage of the Building, the rentable square footage of the Premises, Tenant’s Share of Operating Expenses and the Rent payable hereunder during the unexpired Term shall be reduced to such extent as may be fair and reasonable under the circumstances. Upon any such Taking, Landlord shall be entitled to receive the entire price or award from any such Taking without any payment to Tenant, and Tenant hereby assigns to Landlord Tenant’s interest, if any, in such award; provided, however, that if any of Tenant’s Alterations or Tenant Improvements to the extent paid for by Tenant and not the Tl Allowance are attributed a specific value in and of themselves in connection with the Taking which increases the price or award that would in the absence of such Alterations and Tenant Improvements to the extent paid for by Tenant and not the Tl Allowance have been paid to Landlord, Tenant shall have the right to make a claim for the unamortized value specifically attributable to such Alterations and Tenant Improvements to the extent paid for by Tenant and not the Tl Allowance. Tenant shall have the right, to the extent that same shall not diminish Landlord’s award other than as provided for in the preceding sentence, to make a separate claim against the condemning authority (but not Landlord) for such compensation as may be separately awarded or recoverable by Tenant for moving expenses and damage to Tenant’s trade fixtures, if a separate award for such items is made to Tenant. Tenant hereby waives any and all rights it might otherwise have pursuant to any provision of state law to terminate this Lease upon a partial Taking of the Premises or the Project. Notwithstanding the foregoing, Landlord may not terminate this Lease due to a Taking unless it also terminates the Exelixis Lease.

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

     (a) Payment Defaults. Tenant shall fail to pay any installment of Rent or any other payment hereunder when due; provided, however, that Landlord will give Tenant notice and an opportunity to cure any failure to pay Rent within 3 days of any such notice not more than twice in any 12 month period.

     (b) Insurance. Any insurance required to be maintained by Tenant pursuant to this Lease shall be canceled or terminated or shall expire or shall be reduced or materially changed and Tenant shall fail to restore the required coverage within 5 days after notice from Landlord.

     (c) Abandonment. Tenant shall abandon the Premises.

     (d) Improper Transfer. Tenant shall assign, sublease or otherwise transfer or attempt to transfer all or any portion of Tenant’s interest in this Lease or the Premises except as expressly permitted herein, or Tenant’s interest in this Lease shall be attached, executed upon, or otherwise judicially seized and such action is not released within 90 days of the action.

     (e) Liens. Tenant shall fail to discharge or otherwise obtain the release of any lien placed upon the Premises in violation of this Lease within 10 days after notice to Tenant that any such lien has been filed against the Premises.

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

     (g) Estoppel Certificate or Subordination Agreement. Tenant fails to execute any document required from Tenant under Sections 23 or 27 within 5 days after a second notice requesting such document.

     (h) Other Defaults. Tenant shall fail to comply with any provision of this Lease other than those specifically referred to in this Section 20, and, except to the extent a different time period is otherwise provided for herein, such failure shall continue for a period of 30 days after written notice thereof from Landlord to Tenant.

Any notice given under Section 20(h) hereof shall: (i) specify the alleged default, (ii) demand that Tenant cure such default, (iii) be in lieu of, and not in addition to, or shall be deemed to be, any notice required under any provision of applicable law, and (iv) not be deemed a forfeiture or a termination of this Lease unless Landlord elects otherwise in such notice; provided that if the nature of Tenant’s default pursuant to Section 20(h) is such that it cannot be cured by the payment of money and reasonably requires more than 30 days to cure, then Tenant shall not be deemed to be in default if Tenant commences such cure within said 30 day period and thereafter diligently prosecutes the same to completion; provided, however, that, upon request from Landlord from time to time, Tenant shall provide Landlord with any information reasonably requested by Landlord regarding the prosecution of the cure in question including, without limitation, status reports detailing actions being undertaken by Tenant.

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     21. Landlord’s Remedies.

     (a) Payment By Landlord; Interest. Upon a Default by Tenant hereunder, Landlord may, without waiving or releasing any obligation of Tenant hereunder, make such payment or perform such act on behalf of Tenant. All sums so paid or incurred by Landlord, together with interest thereon, from the date such sums were paid or incurred, at the annual rate equal to 12% per annum or the highest rate permitted by law (the “Default Rate”), whichever is less, shall be payable to Landlord on demand as Additional Rent. Nothing herein shall be construed to create or impose a duty on Landlord to mitigate any damages resulting from Tenant’s Default hereunder.

     (b) Late Payment Rent. Late payment by Tenant to Landlord of Rent and other sums due will cause Landlord to incur costs not contemplated by this Lease, the exact amount of which will be extremely difficult and impracticable to ascertain. Such costs include, but are not limited to, processing and accounting charges and late charges which may be imposed on Landlord under any Mortgage covering the Premises. Therefore, if any installment of Rent due from Tenant is not received by Landlord within 5 days after the date such payment is due, Tenant shall pay to Landlord an additional sum equal to 6% of the overdue Rent as a late charge. Notwithstanding the foregoing, before assessing a late charge the first time in any calendar year, Landlord shall provide Tenant written notice of the delinquency and will waive the right if Tenant pays such delinquency within 5 days thereafter. The parties agree that this late charge represents a fair and reasonable estimate of the costs Landlord will incur by reason of late payment by Tenant. In addition to the late charge, Rent not paid when due shall bear interest at the Default Rate from the 5th day after the date due until paid.

     (c) Remedies. Upon the occurrence of a Default, Landlord, at its option, without further notice or demand to Tenant, shall have in addition to all other rights and remedies provided in this Lease, at law or in equity, the option to pursue any one or more of the following remedies, each and all of which shall be cumulative and nonexclusive, without any notice or demand whatsoever.

     (i) Terminate this Lease, or at Landlord’s option, Tenant’s right to possession only, 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;

     (ii) Upon any termination of this Lease, whether pursuant to the foregoing Section 21(c)(i) or otherwise, Landlord may recover from Tenant the following:

     (A) The worth at the time of award of any unpaid rent which has been earned at the time of such termination; plus

     (B) 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

     (C) The worth at the time of award of the amount by which the unpaid rent for the balance of the Term after the time of award exceeds the amount of such rental loss that Tenant proves could have been reasonably avoided; plus

     (D) 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, to the extent allocable to the remainder of the Term, brokerage commissions and advertising expenses incurred, expenses of

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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

     (E) 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 21 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 Sections 21(c)(ii) (A) and (B), above, the “worth at the time of award” shall be computed by allowing interest at the Default Rate. As used in Section 21(c)(ii)(C) 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 1% .

     (iii) Landlord may continue this Lease in effect after Tenant’s Default and recover rent as it becomes due (Landlord and Tenant hereby agreeing that Tenant has the right to sublet or assign hereunder, subject only to reasonable limitations). Accordingly, if Landlord does not elect to terminate this Lease following a Default by Tenant, Landlord may, from time to time, without terminating this Lease, enforce all of its rights and remedies hereunder, including the right to recover all Rent as it becomes due.

     (iv) After Landlord terminates this Lease following a 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 or may, in Landlord’s sole discretion, succeed to Tenant’s interest in such subleases, licenses, concessions or arrangements. Upon 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.

     (v) Independent of the exercise of any other remedy of Landlord hereunder or under applicable law, Landlord may conduct an environmental test of the Premises as generally described in Section 30(d) hereof, at Tenant’s expense.

     (d) Effect of Exercise. Exercise by Landlord of any remedies hereunder or otherwise available shall not be deemed to be an acceptance of surrender of the Premises and/or a termination of this Lease by Landlord, it being understood that such surrender and/or termination can be effected only by the express written agreement of Landlord and Tenant. Any law, usage, or custom to the contrary notwithstanding, Landlord shall have the right at all times to enforce the provisions of this Lease in strict accordance with the terms hereof; and the failure of Landlord at any time to enforce its rights under this Lease strictly in accordance with same shall not be construed as having created a custom in any way or manner contrary to the specific terms, provisions, and covenants of this Lease or as having modified the same and shall not be deemed a waiver of Landlord’s right to enforce one or more of its rights in connection with any subsequent default. A receipt by Landlord of Rent or other payment with knowledge of the breach of any covenant hereof shall not be deemed a waiver of such breach, and no waiver by Landlord of any provision of this Lease shall be deemed to have been made unless expressed in writing and signed by Landlord. To the greatest extent permitted by law, Tenant waives the service of notice of Landlord’s intention to re-enter, re-take or otherwise obtain possession of the Premises as provided in any statute, or to institute legal proceedings to that end, and also waives all right of redemption in case Tenant shall be dispossessed by a judgment or by warrant of any court or judge. Notwithstanding the foregoing, nothing contained herein shall constitute Tenant’s waiver of its right under applicable Legal Requirements to receive a 3 day notice from Landlord to quit or pay rent prior to Landlord commencing an unlawful detainer action. Any relating of the Premises or any portion thereof shall be on such terms and conditions as Landlord in its sole discretion may determine. Landlord shall not be liable for, nor shall Tenant’s obligations hereunder be diminished because of, Landlord’s failure to relet the Premises or

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collect rent due in respect of such reletting or otherwise to mitigate any damages arising by reason of Tenant’s Default.

     22. Assignment and Subletting.

     (a) General Prohibition. Without Landlord’s prior written consent subject to and on the conditions described in this Section 22, Tenant shall not, directly or indirectly, voluntarily or by operation of law, assign this Lease or sublease the Premises or any part thereof or mortgage, pledge, or hypothecate its leasehold interest or grant any concession or license within the Premises, and any attempt to do any of the foregoing shall be void and of no effect.

     (b) Permitted Transfers. If Tenant desires to assign, sublease, hypothecate or otherwise transfer this Lease or sublet the Premises other than pursuant to a Permitted Assignment (as defined below), then at least 15 business days, but not more than 45 business days, before the date Tenant desires the assignment or sublease to be effective (the “Assignment Date”), Tenant shall give Landlord a notice (the “Assignment Notice”) containing such information about the proposed assignee or sublessee, including the proposed use of the Premises and any Hazardous Materials proposed to be used, stored handled, treated, generated in or released or disposed of from the Premises, the Assignment Date, any relationship between Tenant and the proposed assignee or sublessee, and all material terms and conditions of the proposed assignment or sublease, including a copy of any proposed assignment or sublease in its final form, and such other information as Landlord may deem reasonably necessary or appropriate to its consideration whether to grant its consent. Landlord may, by giving written notice to Tenant within 15 business days after receipt of the Assignment Notice: (i) grant such consent, or (ii) refuse such consent, in its reasonable discretion. Among other reasons, it shall be reasonable for Landlord to withhold its consent in any of these instances: (1) the proposed assignee or subtenant is a governmental agency; (2) in Landlord’s reasonable judgment, the use of the Premises by the proposed assignee or subtenant would entail any alterations that would materially lessen the value of the leasehold improvements in the Premises; (3) Landlord has experienced previous defaults by or is in litigation with the proposed assignee or subtenant; (4) the use of the Premises by the proposed assignee or subtenant will violate any applicable Legal Requirement; (5) the proposed assignee or subtenant is an entity with whom Landlord has agreed to a letter of intent to lease space in the Project; or (6) the assignment or sublease is prohibited by Landlord’s lender. No failure of Landlord to deliver a timely notice in response to the Assignment Notice, shall be deemed to be Landlord’s consent to the proposed assignment, sublease or other transfer. Tenant shall pay to Landlord a fee equal to One Thousand Five Hundred Dollars ($1,500) in connection with its consideration of any Assignment Notice and/or its preparation or review of any consent documents. Notwithstanding the foregoing, Landlord’s consent to an assignment of this Lease or a subletting of any portion of the Premises to any entity controlling, controlled by or under common control with Tenant (a “Control Permitted Assignment”) shall not be required, provided that Landlord shall have the right to approve the form of any such sublease or assignment (which approval shall not be unreasonably withheld or delayed). In addition, Tenant shall have the right to assign this Lease, provided that Tenant delivers written notice thereof to Landlord within 5 business days thereafter but without obtaining Landlord’s prior written consent, to a corporation or other entity which is a successor-in-interest to Tenant, by way of merger, consolidation or corporate reorganization, or by the purchase of all or substantially all of the assets or the ownership interests of Tenant provided that (i) such merger or consolidation, or such acquisition or assumption, as the case may be, is for a good business purpose and not principally for the purpose of transferring the Lease, and (ii) the net worth (as determined in accordance with generally accepted accounting principles (“GAAP”)) of the assignee is not less than the greater of the net worth (as determined in accordance with GAAP) of Tenant as of the date of Tenant’s most current quarterly or annual financial statements, and (iii) such assignee shall agree in writing to assume all of the terms, covenants and conditions of this Lease arising after the effective date of the assignment (a “Corporate Permitted Assignment”). Control Permitted Assignments and Corporate Permitted Assignments are hereinafter referred to as “Permitted Assignments.”

     (c) Additional Conditions. As a condition to any such assignment or subletting, whether or not Landlord’s consent is required, Landlord may require:

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     (i) that any assignee or subtenant agree, in writing at the time of such assignment or subletting, that if Landlord gives such party notice that Tenant is in default under this Lease, such party shall thereafter make all payments otherwise due Tenant directly to Landlord, which payments will be received by Landlord without any liability except to credit such payment against those due under the Lease, and any such third party shall agree to attorn to Landlord or its successors and assigns should this Lease be terminated for any reason; provided, however, in no event shall Landlord or its successors or assigns be obligated to accept such attornment; and

     (ii) A list of Hazardous Materials, certified by the proposed assignee or sublessee to be true and correct, which the proposed assignee or sublessee intends to use, store, handle, treat, generate in or release or dispose of from the Premises, together with copies of all documents relating to such use, storage, handling, treatment, generation, release or disposal of Hazardous Materials by the proposed assignee or subtenant in the Premises or on the Project, prior to the proposed assignment or subletting, including, without limitation: permits; approvals; reports and correspondence; storage and management plans; plans relating to the installation of any storage tanks to be installed in or under the Project (provided, said installation of tanks shall only be permitted after Landlord has given its written consent to do so, which consent may be withheld in Landlord’s sole and absolute discretion); and all closure plans or any other documents required by any and all federal, state and local Governmental Authorities for any storage tanks installed in, on or under the Project for the closure of any such tanks. Neither Tenant nor any such proposed assignee or subtenant is required, however, to provide Landlord with any portion(s) of the such documents containing information of a proprietary nature which, in and of themselves, do not contain a reference to any Hazardous Materials or hazardous activities.

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

     (e) No Waiver. The consent by Landlord to an assignment or subletting shall not relieve Tenant or any assignees of this Lease or any sublessees of the Premises from obtaining the consent of Landlord to any further assignment or subletting nor shall it release Tenant or any assignee or sublessee of Tenant from full and primary liability under the Lease. The acceptance of Rent hereunder, or the acceptance of performance of any other term, covenant, or condition thereof, from any other person or entity shall not be deemed to be a waiver of any of the provisions of this Lease or a consent to any subletting, assignment or other transfer of the Premises.

     (f) Prior Conduct of Proposed Transferee. Notwithstanding any other provision of this Section 22, if (i) the proposed assignee or sublessee of Tenant has been required by any prior landlord, lender or Governmental Authority to take remedial action in connection with Hazardous Materials contaminating a property, where the contamination resulted from such party’s action or use of the property in question, (ii) the proposed assignee or sublessee is subject to an enforcement order issued by any Governmental Authority in connection with the use, storage, handling, treatment, generation, release

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or disposal of Hazardous Materials (including, without limitation, any order related to the failure to make a required reporting to any Governmental Authority), or (iii) because of the existence of a pre-existing environmental condition in the vicinity of or underlying the Project, the risk that Landlord would be targeted as a responsible party in connection with the remediation of such pre-existing environmental condition would be materially increased or exacerbated by the proposed use of Hazardous Materials by such proposed assignee or sublessee, Landlord shall have the absolute right to refuse to consent to any assignment or subletting to any such party.

     23. Estoppel Certificate. Tenant shall, within 10 business days of written notice from Landlord, execute, acknowledge and deliver a statement in writing in any form reasonably requested by a proposed lender or purchaser, (i) certifying that this Lease is unmodified and in full force and effect (or, if modified, stating the nature of such modification and certifying that this Lease as so modified is in full force and effect) and the dates to which the rental and other charges are paid in advance, if any, (ii) acknowledging that there are not any uncured defaults on the part of Landlord hereunder, or specifying such defaults if any are claimed, and (iii) setting forth such further information with respect to the status of this Lease or the Premises as may be requested thereon. Any such statement may be relied upon by any prospective purchaser or encumbrancer of all or any portion of the real property of which the Premises are a part. Tenant’s failure to deliver such statement within such time shall, at the option of Landlord, be conclusive upon Tenant that the Lease is in full force and effect and without modification except as may be represented by Landlord in any certificate prepared by Landlord and delivered to Tenant for execution.

     24. Quiet Enjoyment. So long as Tenant is not in Default under this Lease, Tenant shall, subject to the terms of this Lease, at all times during the Term, have peaceful and quiet enjoyment of the Premises against any person claiming by, through or under Landlord.

     25. Prorations. All prorations required or permitted to be made hereunder shall be made on the basis of a 360 day year and 30 day months.

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

     27. Subordination. This Lease and Tenant’s interest and rights hereunder are hereby made and shall be subject and subordinate at all times to the lien of any Mortgage now existing or hereafter created on or against the Project or the Premises, and all amendments, restatements, renewals, modifications, consolidations, refinancing, assignments and extensions thereof, without the necessity of any further instrument or act on the part of Tenant; provided, however that so long as there is no Default hereunder by Tenant such subordination shall be subject to Landlord’s SNDA Obligation (as defined below). Tenant agrees, at the election of the Holder of any such Mortgage, to attorn to any such Holder. Tenant agrees upon demand to execute, acknowledge and deliver such instruments, confirming such subordination, and such instruments of attornment as shall be requested by any such Holder, provided any such instruments contain appropriate non-disturbance provisions assuring Tenant’s quiet enjoyment of the Premises as set forth in this Section 27 and Section 24 hereof. Notwithstanding the foregoing, any such Holder may at any time subordinate its Mortgage to this Lease, without Tenant’s consent, by notice in writing to Tenant, and thereupon this Lease shall be deemed prior to such Mortgage without regard to their respective dates of execution, delivery or recording and in that event such Holder shall have the same rights with respect to this Lease as though this Lease had been executed prior to the execution, delivery and recording of such Mortgage and had been assigned to such Holder. The term “Mortgage” whenever used in this Lease shall be deemed to include deeds of trust, security assignments and any other encumbrances, and any reference to the “Holder” of a Mortgage shall be deemed to include the beneficiary under a deed of trust. As of the date of this Lease, Landlord represents that there is no

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existing Mortgage encumbering the Project. Upon written request from Tenant, Landlord shall use reasonable efforts to obtain for execution by Tenant a commercially reasonable form of subordination, non-disturbance and attornment agreement (a “SNDA”) executed by the Holder of any future Mortgage with a lien on the Project which provides subject to the terms and carve-outs reasonably required by the Holder in such SNDA, among other things, that so long as Tenant is not in Default of its obligations under this Lease, foreclosure or other enforcement of such Mortgage shall not terminate this Lease and the successor to Landlord’s interest in the Project shall recognize and be bound by the terms of this Lease and, if applicable, the Exelixis Lease (and Landlord’s consent to the Exelixis Sublease) including the provisions of Section 5(f) of the Work Letter and Tenant’s right to possession of the Premises (“Landlord’s SNDA Obligation”). Tenant acknowledges and agrees that the SNDA may provide that in no event shall any such Holder and/or the successor to Landlord’s interest in the Project: (i) be liable for any act or omission of any prior landlord or with respect to events occurring prior to acquisition of ownership and, with respect to any continuing failure by Landlord under the Lease such as the failure to perform required maintenance and repairs, such failure shall as to such Holder or successor only be deemed to have commenced from and after the date that such party succeeds to Landlord’s interest in the Project and obtains written notice from Tenant of the failure in question; (ii) except for Section 5(f) of the Work Letter, be subject to any offsets or defenses which Tenant might have against any prior landlord, (iii) be bound by prepayment of more than one (1) month’s rent, or (iv) be obligated to be bound by any modifications or amendments to this Lease not consented to in writing by such Holder or successor to Landlord’s interest in the Project.

     28. Surrender. Upon the expiration of the Term or earlier termination of Tenant’s right of possession, Tenant shall surrender the Premises to Landlord in the same condition as received, subject to any Alterations or Installations permitted by Landlord to remain in the Premises, free of Hazardous Materials brought upon, kept, used, stored, handled, treated, generated in, or released or disposed of from, the Premises by any person other than a Landlord Party (collectively, “Tenant HazMat Operations”) and released of all Hazardous Materials Clearances, broom clean, ordinary wear and tear and casualty loss and condemnation covered by Sections 18 and 19 excepted. At least 3 months prior to the surrender of the Premises, Tenant shall deliver to Landlord a narrative description of the actions proposed (or required by any Governmental Authority) to be taken by Tenant in order to surrender the Premises (including any Installations permitted by Landlord to remain in the Premises) at the expiration or earlier termination of the Term, free from any residual impact from the Tenant HazMat Operations and otherwise released for unrestricted use and occupancy (the “Surrender Plan”). Such Surrender Plan shall be accompanied by a current listing of (i) all Hazardous Materials licenses and permits held by or on behalf of any Tenant Party with respect to the Premises, and (ii) all Hazardous Materials used, stored, handled, treated, generated, released or disposed of from the Premises, and shall be subject to the review and approval of Landlord’s environmental consultant, such approval not to be unreasonably withheld or delayed. In connection with the review and approval of the Surrender Plan, upon the request of Landlord, Tenant shall deliver to Landlord or its consultant such additional non-proprietary information concerning Tenant HazMat Operations as Landlord shall request. On or before such surrender, Tenant shall deliver to Landlord evidence that the approved Surrender Plan shall have been satisfactorily completed and Landlord shall have the right, subject to reimbursement at Tenant’s expense as set forth below, to cause Landlord’s environmental consultant to inspect the Premises and perform such additional procedures as may be deemed reasonably necessary to confirm that the Premises are, as of the effective date of such surrender or early termination of the Lease, free from any residual impact from Tenant HazMat Operations. Tenant shall reimburse Landlord, as Additional Rent, for the actual reasonable out-of pocket expense incurred by Landlord for Landlord’s environmental consultant to review and approve the Surrender Plan and to visit the Premises and verify satisfactory completion of the same, which cost shall not exceed $5,000. Landlord shall have the unrestricted right to deliver such Surrender Plan and any report by Landlord’s environmental consultant with respect to the surrender of the Premises to third parties.

     If Tenant shall fail to prepare or submit a Surrender Plan approved by Landlord, or if Tenant shall fail to complete the approved Surrender Plan, or if such Surrender Plan, whether or not approved by Landlord, shall fail to adequately address any residual effect of Tenant HazMat Operations in, on or about

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the Premises, Landlord shall have the right to take such actions as Landlord may deem reasonable or appropriate to assure that the Premises and the Project are surrendered free from any residual impact from Tenant HazMat Operations, the cost of which actions shall be reimbursed by Tenant as Additional Rent, without regard to the limitation set forth in the first paragraph of this Section 28.

     Tenant shall immediately return to Landlord all keys to parking, the Project, restrooms or all or any portion of the Premises furnished to or otherwise procured by Tenant. If any such key is lost, Tenant shall pay to Landlord, at Landlord’s election, either the cost of replacing such lost key or changing the lock or locks opened by such lost key. Any Tenant’s Property, Alterations and property not so removed by Tenant as permitted or required herein shall be deemed abandoned and may be stored, removed, and disposed of by Landlord at Tenant’s expense, and Tenant waives all claims against Landlord for any damages resulting from Landlord’s retention and/or disposition of such property. All obligations of Tenant hereunder not fully performed as of the termination of the Term, including the obligations of Tenant under Section 30 hereof, shall survive the expiration or earlier termination of the Term, including, without limitation, indemnity obligations, payment obligations with respect to Rent and obligations concerning the condition and repair of the Premises.

     29. Waiver of Jury Trial. TO THE EXTENT PERMITTED BY LAW, TENANT AND LANDLORD WAIVE ANY RIGHT TO TRIAL BY JURY OR TO HAVE A JURY PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT, OR OTHERWISE, BETWEEN LANDLORD AND TENANT ARISING OUT OF THIS LEASE OR ANY OTHER INSTRUMENT, DOCUMENT, OR AGREEMENT EXECUTED OR DELIVERED IN CONNECTION HEREWITH OR THE TRANSACTIONS RELATED HERETO.

     30. Environmental Requirements.

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

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existing prior to the time of such contamination, provided that Landlord’s approval of such action shall first be obtained, which approval shall not unreasonably be withheld so long as such actions would not potentially have any material adverse long-term or short-term effect on the Premises, the Building or the Project. Notwithstanding anything to the contrary contained in Section 28 or this Section 30, Tenant shall not be responsible for or have any liability to Landlord, and the indemnification and hold harmless obligation set forth in this paragraph shall not apply to (i) contamination in the Premises which Tenant can prove to Landlord’s reasonable satisfaction existed in the Premises immediately prior to the Commencement Date, (ii) the presence of any Hazardous Materials in the Premises which Tenant can prove to Landlord’s reasonable satisfaction migrated from outside of the Premises into the Premises, or (iii) any Hazardous Materials that Tenant can prove to Landlord’s reasonable satisfaction were not brought upon, kept, used, stored, handled, treated, generated in, or released or disposed of from, the Project by Tenant or any Tenant Party, unless in any case, the presence of such Hazardous Materials (x) is the result of a breach by Tenant of any of its obligations under this Lease, or (y) was caused, contributed to or exacerbated by Tenant or any Tenant Party.

     (b) Business. Landlord acknowledges that it is not the intent of this Section 30 to prohibit Tenant from using the Premises for the Permitted Use. Tenant may operate its business according to prudent industry practices so long as the use or presence of Hazardous Materials is strictly and properly monitored according to all then applicable Environmental Requirements. As a material inducement to Landlord to allow Tenant to use Hazardous Materials in connection with its business, Tenant agrees to deliver to Landlord prior to the Commencement Date a list identifying each type of Hazardous Materials to be brought upon, kept, used, stored, handled, treated, generated on, or released or disposed of from, the Premises and setting forth any and all governmental approvals or permits required in connection with the presence, use, storage, handling, treatment, generation, release or disposal of such Hazardous Materials on or from the Premises (“Hazardous Materials List”). Tenant shall deliver to Landlord an updated Hazardous Materials List at least once per calendar year listing all Hazardous Materials which Tenant is required to disclose to any Governmental Authority (e.g., the fire department) in connection with its use or occupancy of the Premises. Tenant shall deliver to Landlord true and correct copies of the following documents (the “Haz Mat Documents”) relating to the use, storage, handling, treatment, generation, release or disposal of Hazardous Materials prior to the Commencement Date, or if unavailable at that time, concurrent with the receipt from or submission to a Governmental Authority: permits; approvals; reports and correspondence; storage and management plans, notice of violations of any Legal Requirements; plans relating to the installation of any storage tanks to be installed in or under the Project (provided, said installation of tanks shall only be permitted after Landlord has given Tenant its written consent to do so, which consent may be withheld in Landlord’s sole and absolute discretion); all closure plans or any other documents required by any and all federal, state and local Governmental Authorities for any storage tanks installed in, on or under the Project for the closure of any such tanks; and a Surrender Plan (to the extent surrender in accordance with Section 28 cannot be accomplished in 3 months). Tenant is not required, however, to provide Landlord with any portion(s) of the Haz Mat Documents containing information of a proprietary nature which, in and of themselves, do not contain a reference to any Hazardous Materials or hazardous activities. It is not the intent of this Section to provide Landlord with information which could be detrimental to Tenant’s business should such information become possessed by Tenant’s competitors.

     (c) Tenant Representation and Warranty. Tenant hereby represents and warrants to Landlord that (i) neither Tenant nor any of its legal predecessors has been required by any prior landlord, lender or Governmental Authority at any time to take remedial action in connection with Hazardous Materials contaminating a property which contamination was permitted by Tenant of such predecessor or resulted from Tenant’s or such predecessor’s action or use of the property in question, and (ii) Tenant is not subject to any enforcement order issued by any Governmental Authority in connection with the use, storage, handling, treatment, generation, release or disposal of Hazardous Materials (including, without limitation, any order related to the failure to make a required reporting to any Governmental Authority). If Landlord determines that this representation and warranty was not true as of the date of this lease, Landlord shall have the right to terminate this Lease in Landlord’s sole and absolute discretion.

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     (d) Testing. Landlord shall have the right to conduct annual tests of the Premises to determine whether any contamination of the Premises or the Project has occurred as a result of Tenant’s use. Tenant shall be required to pay the cost of such annual test of the Premises only if there is violation of this Section 30 or if contamination for which Tenant is responsible under this Section 30 is identified; provided, however, that if Tenant conducts its own tests of the Premises using third party contractors and test procedures acceptable to Landlord which tests are certified to Landlord, Landlord shall accept such tests in lieu of the annual tests. In addition, at any time, and from time to time, prior to the expiration or earlier termination of the Term, Landlord shall have the right to conduct appropriate tests of the Premises and the Project to determine if contamination has occurred as a result of Tenant’s use of the Premises. In connection with such testing, upon the request of Landlord, Tenant shall deliver to Landlord or its consultant such non-proprietary information concerning the use of Hazardous Materials in or about the Premises by Tenant or any Tenant Party. If contamination has occurred for which Tenant is liable under this Section 30, Tenant shall pay all costs to conduct such tests. If no such contamination is found, Landlord shall pay the costs of such tests (which shall not constitute an Operating Expense). Landlord shall provide Tenant with a copy of all third party, non-confidential reports and tests of the Premises made by or on behalf of Landlord during the Term without representation or warranty and subject to a confidentiality agreement. Tenant shall, at its sole cost and expense, promptly and satisfactorily remediate any environmental conditions identified by such testing in accordance with all Environmental Requirements. Landlord’s receipt of or satisfaction with any environmental assessment in no way waives any rights which Landlord may have against Tenant.

     (e) Control Areas. Tenant shall comply with all Legal Requirements applicable to the storage of Hazardous Materials at the Project.

     (f) Underground Tanks. If underground or other storage tanks storing Hazardous Materials located on the Premises or the Project are used by Tenant or are hereafter placed on the Premises or the Project by Tenant, Tenant shall install, use, monitor, operate, maintain, upgrade and manage such storage tanks, maintain appropriate records, obtain and maintain appropriate insurance, implement reporting procedures, properly close any underground storage tanks, and take or cause to be taken all other actions necessary or required under applicable state and federal Legal Requirements, as such now exists or may hereafter be adopted or amended in connection with the installation, use, maintenance, management, operation, upgrading and closure of such storage tanks.

     (g) Tenant’s Obligations. Tenant’s obligations under this Section 30 shall survive the expiration or earlier termination of the Lease. During any period of time after the expiration or earlier termination of this Lease required by Tenant or Landlord to complete the removal from the Premises of any Hazardous Materials (including, without limitation, the release and termination of any licenses or permits restricting the use of the Premises and the completion of the approved Surrender Plan), Tenant shall continue to pay the full Rent in accordance with this Lease for any portion of the Premises not relet by Landlord in Landlord’s sole discretion, which Rent shall be prorated daily.

     (h) Definitions. As used herein, the term “Environmental Requirements” means all applicable present and future statutes, regulations, ordinances, rules, codes, judgments, orders or other similar enactments of any Governmental Authority regulating or relating to health, safety, or environmental conditions on, under, or about the Premises or the Project, or the environment, including without limitation, the following: the Comprehensive Environmental Response, Compensation and Liability Act; the Resource Conservation and Recovery Act; and all state and local counterparts thereto, and any regulations or policies promulgated or issued thereunder. As used herein, the term “Hazardous Materials” means and includes any substance, material, waste, pollutant, or contaminant listed or defined as hazardous or toxic, or regulated by reason of its impact or potential impact on humans, animals and/or the environment under any Environmental Requirements, asbestos and petroleum, including crude oil or any fraction thereof, natural gas liquids, liquefied natural gas, or synthetic gas usable for fuel (or mixtures of natural gas and such synthetic gas). As defined in Environmental Requirements, Tenant is and shall be deemed to be the “operator” of Tenant’s “facility” and the “owner” of all Hazardous Materials brought

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on the Premises by Tenant or any Tenant Party, and the wastes, by-products, or residues generated, resulting, or produced therefrom.

     31. Tenant’s Remedies/Limitation of Liability. Landlord shall not be in default hereunder unless Landlord fails to perform any of its obligations hereunder within 30 days after written notice from Tenant specifying such failure (unless such performance will, due to the nature of the obligation, require a period of time in excess of 30 days, then after such period of time as is reasonably necessary). Upon any default by Landlord, Tenant shall give notice by registered or certified mail to any Holder of a Mortgage covering the Premises and to any landlord of any lease of property in or on which the Premises are located and Tenant shall offer such Holder and/or landlord a reasonable opportunity to cure the default, including time to obtain possession of the Project by power of sale or a judicial action if such should prove necessary to effect a cure; provided Landlord shall have furnished to Tenant in writing the names and addresses of all such persons who are to receive such notices. All obligations of Landlord hereunder shall be construed as covenants, not conditions; and, except as may be otherwise expressly provided in this Lease, Tenant may not terminate this Lease for breach of Landlord’s obligations hereunder.

     All obligations of Landlord under this Lease will be binding upon Landlord only during the period of its ownership of the Premises and not thereafter. The term “Landlord” in this Lease shall mean only the owner for the time being of the Premises. Upon the transfer by such owner of its interest in the Premises, such owner shall thereupon be released and discharged from all obligations of Landlord thereafter accruing, but such obligations shall be binding during the Term upon each new owner for the duration of such owner’s ownership.

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

     33. Security. Tenant acknowledges and agrees that security devices and services, if any, while intended to deter crime may not in given instances prevent theft or other criminal acts and that Landlord is not providing any security services with respect to the Premises. Tenant agrees that Landlord shall not be liable to Tenant for, and Tenant waives any claim against Landlord with respect to, any loss by theft or any other damage suffered or incurred by Tenant in connection with any unauthorized entry into the Premises or any other breach of security with respect to the Premises. Tenant shall be solely responsible for the personal safety of Tenant’s officers, employees, agents, contractors, guests and invitees while any such person is in, on or about the Premises and/or the Project. Tenant shall at Tenant’s cost obtain insurance coverage to the extent Tenant desires protection against such criminal acts.

     34. Force Majeure. Neither Tenant nor Landlord shall be responsible or liable for delays in the performance of its obligations hereunder when caused by, related to, or arising out of acts of God, sinkholes or subsidence, strikes, lockouts, or other labor disputes, embargoes, quarantines, weather, national, regional, or local disasters, calamities, or catastrophes, inability to obtain labor or materials (or

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reasonable substitutes therefor) at reasonable costs or failure of, or inability to obtain, utilities necessary for performance, governmental restrictions, orders, limitations, regulations, or controls, national emergencies, delay in issuance or revocation of permits, enemy or hostile governmental action, terrorism, insurrection, riots, civil disturbance or commotion, fire or other casualty, and other causes or events beyond the reasonable control of such party (“Force Majeure”); provided, however, that Force Majeure shall not include the inability to pay money (including, without limitation, the Rent due Landlord hereunder), general economic conditions, restrictions on the availability of credit or money, or other causes related to the particular financial condition of a party. Any party claiming Force Majeure shall be required to notify the other party of such Force Majeure promptly after the commencement of such Force Majeure and shall be required to keep such other party reasonably informed regarding the same throughout the period during which Force Majeure is being claimed. If the happening of any such Force Majeure event only partially impairs the performance of a party’s obligations hereunder, such party shall continue to perform under this Lease to the fullest extent possible in light of such Force Majeure event.

     35. Brokers. Landlord and Tenant each represents and warrants that it has not dealt with any broker, agent or other person (collectively, “Broker”) in connection with this transaction and that no Broker brought about this transaction, other than CB Richard Ellis and Cresa Partners. Landlord and Tenant each hereby agree to indemnify and hold the other harmless from and against any claims by any Broker, other than the broker, if any named in this Section 35, claiming a commission or other form of compensation by virtue of having dealt with Tenant or Landlord, as applicable, with regard to this leasing transaction. Landlord shall be responsible for all fees of Broker arising out of the execution of this Lease in accordance with the terms of a separate written agreement between Broker and Landlord.

     36. Limitation on Landlord’s Liability. NOTWITHSTANDING ANYTHING SET FORTH HEREIN OR IN ANY OTHER AGREEMENT BETWEEN LANDLORD AND TENANT TO THE CONTRARY: (A) LANDLORD SHALL NOT BE LIABLE TO TENANT OR ANY OTHER PERSON FOR (AND TENANT AND EACH SUCH OTHER PERSON ASSUME ALL RISK OF) LOSS, DAMAGE OR INJURY, WHETHER ACTUAL OR CONSEQUENTIAL TO: TENANTS PERSONAL PROPERTY OF EVERY KIND AND DESCRIPTION, INCLUDING, WITHOUT LIMITATION TRADE FIXTURES, EQUIPMENT, INVENTORY, SCIENTIFIC RESEARCH, SCIENTIFIC EXPERIMENTS, LABORATORY ANIMALS, PRODUCT, SPECIMENS, SAMPLES, AND/OR SCIENTIFIC, BUSINESS, ACCOUNTING AND OTHER RECORDS OF EVERY KIND AND DESCRIPTION KEPT AT THE PREMISES AND ANY AND ALL INCOME DERIVED OR DERIVABLE THEREFROM; (B) THERE SHALL BE NO PERSONAL RECOURSE TO LANDLORD FOR ANY ACT OR OCCURRENCE IN, ON OR ABOUT THE PREMISES OR ARISING IN ANY WAY UNDER THIS LEASE OR ANY OTHER AGREEMENT BETWEEN LANDLORD AND TENANT WITH RESPECT TO THE SUBJECT MATTER HEREOF AND ANY LIABILITY OF LANDLORD HEREUNDER SHALL BE STRICTLY LIMITED SOLELY TO LANDLORD’S INTEREST IN THE PROJECT OR ANY PROCEEDS FROM SALE OR CONDEMNATION THEREOF AND ANY INSURANCE PROCEEDS PAYABLE IN RESPECT OF LANDLORD’S INTEREST IN THE PROJECT OR IN CONNECTION WITH ANY SUCH LOSS; AND (C) IN NO EVENT SHALL ANY PERSONAL LIABILITY BE ASSERTED AGAINST LANDLORD IN CONNECTION WITH THIS LEASE NOR SHALL ANY RECOURSE BE HAD TO ANY OTHER PROPERTY OR ASSETS OF LANDLORD OR ANY OF LANDLORD’S OFFICERS, DIRECTORS, EMPLOYEES, AGENTS OR CONTRACTORS. UNDER NO CIRCUMSTANCES SHALL LANDLORD OR ANY OF LANDLORDS OFFICERS, DIRECTORS, EMPLOYEES, AGENTS OR CONTRACTORS BE LIABLE FOR INJURY TO TENANT’S BUSINESS OR FOR ANY LOSS OF INCOME OR PROFIT THEREFROM.

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

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     38. Signs; Exterior Appearance. Tenant shall not, without the prior written consent of Landlord, which may be granted or withheld in Landlord’s sole discretion: (i) attach any awnings, exterior lights, decorations, balloons, flags, pennants, banners, painting or other projection to any outside wall of the Project, (ii) use any curtains, blinds, shades or screens other than Landlord’s standard window coverings, (iii) coat or otherwise sunscreen the interior or exterior of any windows, (iv) place any bottles, parcels, or other articles on the window sills, (v) place any equipment, furniture or other items of personal property on any exterior balcony which can be viewed from the exterior of the Premises, or (iv) paint, affix or exhibit on any part of the Premises or the Project any signs, notices, window or door lettering, placards, decorations, or advertising media of any type which can be viewed from the exterior of the Premises. Interior signs on doors and the directory tablet shall be inscribed, painted or affixed for Tenant by Landlord at the sole cost and expense of Tenant.

     Within 60 days of the Commencement Date, Landlord shall, at Landlord’s sole cost, (a) remove the names on the existing monument sign closest to the Building and replace them with Tenant’s name and logo and (b) remove the existing Exelixis signage on the Building and replace it with Tenant’s name and logo as provided in this paragraph. Tenant shall have the exclusive right to display, at Landlord’s cost and expense, Tenant’s name and/or logo on the Building monument sign located on E. Grand Avenue (“Monument Sign”). Tenant shall also have the exclusive right to display, at Tenant’s cost and expense, signs bearing Tenant’s name and/or logo at locations on the Building acceptable to Landlord, in Landlord’s reasonable discretion. Notwithstanding the foregoing, Tenant acknowledges and agrees that Tenant’s name signage on the Monument Sign and on the Building including, without limitation, the size, color and type, shall be subject to Landlord’s prior written approval and shall be consistent with Landlord’s signage program at the Project and applicable Legal Requirements. Tenant shall be responsible, at Tenant’s sole cost and expense, for the maintenance of Tenant’s signs, for the removal of Tenant’s signs at the expiration or earlier termination of this Lease and for the repair all damage resulting from such removal. Landlord hereby approves of the signage described in Exhibit H attached hereto.

     39. Right to Expand.

     (a) Expansion in the Project. Tenant shall have the one-time right, commencing on the Commencement Date and exercisable on or before that date that is 36 months after the Rent Commencement Date (“Expansion Right Expiration Date”), to elect to lease (the “Expansion Right”) a minimum of 60% of the rentable square footage of that certain building (“Expansion Space”) (in locations within the building reasonably acceptable to both Landlord and Tenant but Landlord may require Tenant to lease all of the space on particular contiguous floor(s) before Tenant is permitted to lease space on any other floor) to be constructed (“Northern Facility”) in approximately the location on the land shown on Exhibit G attached hereto (“Northern Facility Land”), which Northern Facility Landlord currently anticipates will contain 5 floors and a total of approximately 161,942 rentable square feet of space. Notwithstanding the foregoing, Tenant acknowledges and agrees that (i) Landlord shall have no obligation to commence design and/or construction of the Northern Facility prior to Tenant delivering an Expansion Exercise Notice (as defined below) to Landlord, and (ii) the number of floors and anticipated square footage of the Northern Facility is not guaranteed and is subject to change by Landlord. If Tenant elects to exercise the Expansion Right, Tenant shall, on or before the Expansion Right Expiration Date, deliver irrevocable written notice to Landlord of its election to exercise the Expansion Right (“Expansion Exercise Notice”), which Expansion Exercise Notice will set forth how much of the Northern Facility Tenant elects to lease but in no event shall Tenant be permitted to lease less than 60% of the rentable square footage of the Northern Facility. Tenant acknowledges and agrees that if Tenant elects to exercise its Expansion Right, then, commencing on the Expansion Space Rent Commencement Date (as defined below), the Base Term of this Lease for the Premises shall automatically be extended for 10 years and the Base Rent for the Premises shall continue at the then current rate with the annual Rent Adjustment Percentage escalations, but Tenant shall nonetheless be required to comply with the other provisions of the lease agreement or lease amendment entered into with respect to the Expansion Space following the mutual execution and delivery of the same. (For example, if the Expansion Space Rent Commencement Date for the Expansion Space is January 1, 2012, then the Base Term of the Lease for the Premises and the Expansion Premises shall expire on December 31, 2021.) Tenant acknowledges

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and agrees that if Tenant elects to lease the Expansion Space as provided for in this Section 39(a) prior to the Expansion Right Expiration Date, all of the terms and conditions of this Lease shall apply to the leasing of the Expansion Space, except that: (i) the definitions on page 1 of the Lease shall be amended as necessary to document and reflect the addition of the Northern Facility to the Project and Tenant’s leasing of the Expansion Space plus an increase in the Security Deposit to reflect one month of Base Rent for the Expansion Space; (ii) Base Rent shall be determined pursuant to the provisions of Section 39(a)(D) below but in no event shall the initial Base Rent for the Expansion Space be more than $3.50 per rentable square foot per month and the same shall increase as provided for in Section 4(b) on each anniversary of the Expansion Space Rent Commencement Date; (iii) the “Expansion Space Rent Commencement Date” shall be the date that is 9 months after the Shell Delivery Date (as defined below) (“Tenant’s Build-Out Period”) and Tenant shall commence paying Base Rent and Operating Expenses for the Expansion Space on such date except that such date shall be extended on a day for day basis due to any Force Majeure and Landlord Delay applicable to Tenant’s construction of the Expansion Space Tenant Improvements; (iv) Tenant shall be responsible for the construction of tenant improvements in the Expansion Space desired by Tenant which improvements shall be of a fixed and permanent nature approved by Landlord (“Expansion Space Tenant Improvements”) and the parties shall enter into a work letter for the Expansion Space substantially in the form of Exhibit C but, instead of the Tenant Improvement Allowance and Additional Tenant Improvement Allowance provided for in Section 5 of the Work Letter, Tenant shall receive a tenant improvement allowance in the amount of $150 per rentable square foot of the Expansion Space (“Expansion Space Work Letter”) which shall be disbursed as provided for in the work letter and Tenant shall have 18 months from the Shell Delivery Date to use such allowance and any amount not used as of the expiration of such 18 month period shall be forfeited; (v) other than systems and facilities dedicated solely to the Expansion Space, Tenant shall not be entitled to maintain the Building Systems in the Northern Facility unless Tenant is leasing the entire Northern Facility; (vi) Landlord shall make available to Tenant its pro-rata share of the signage rights applicable to the Northern Facility; (vii) the provisions of Section 42(s) shall not apply to the Expansion Space and the provisions of Section 42(t) shall apply if Tenant leases the first floor of the Northern Facility as part of the Expansion Space; and (vii) since the Northern Facility may be a multi-tenant building Landlord may require such other changes to the lease for the Expansion Space as would be appropriate for a multi-tenant building. If (x) Tenant does not deliver an Expansion Exercise Notice to Landlord on or before the Expansion Right Expiration Date or (y) no lease amendment or lease agreement for the Expansion Space (including a Expansion Space Work Letter), acceptable to Landlord and Tenant, each in their respective reasonable discretion, has been executed and delivered by the parties within 20 days after Landlord delivers a draft of the same to Tenant despite the good faith efforts of both parties, Tenant shall be deemed to have forever waived its right to lease the Expansion Space and this Section 39(a) shall terminate and be of no further force or effect.

In addition to the foregoing, the following provisions shall apply following Tenant’s election to exercise the Expansion Right:

     (A) Northern Facility, Architects and Contractors. Landlord shall be obligated to construct the Building Shell for the Northern Facility. As used herein, “Building Shell” shall mean a warm building shell comparable to the warm building shell constructed by Landlord for the Building.

          Tenant acknowledges and agrees that the architect for the Northern Facility shall be selected by Landlord, subject to Tenant’s approval, which approval shall not be unreasonably withheld, conditioned or delayed. In addition, Landlord shall competitively bid the construction of the Northern Facility to 3 general contractors selected by Landlord. Landlord shall select the winning bidder, subject to Tenant’s approval of the selected bid, which approval shall not be unreasonably withheld, conditioned or delayed. Landlord shall thereafter enter into a guaranteed maximum price contract with the selected general contractor.

     (B) Plans. The plans for the Northern Facility shall be prepared by Landlord and shall be subject to Tenant’s approval which shall not be unreasonably withheld, conditioned or

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delayed and may in no event increase Landlord’s costs or reduce the rentable square footage of the Northern Facility. Any changes requested by Tenant shall be set forth in a written change order. Tenant acknowledges and agrees that, subject to changes in Legal Requirements, Tenant’s approval shall not be required for the Building Shell to the extent that the same is comparable to the warm building shell which Landlord constructed for the Building. Notwithstanding anything to the contrary contained herein, to the extent set forth in a written change order, Tenant shall be solely responsible for paying for any costs in connection with any changes which Tenant requests to the Building Shell (including, without limitation, with respect to any plans) whether or not such changes are made, and any delays in the design and/or construction of the Northern Facility caused by Tenant and/or any Tenant Party shall reduce Tenant’s Build-Out Period on a day for day basis. Tenant acknowledges that certain plans and other information that may be made available Tenant pursuant to the provisions of this Section 39 constitute information that Landlord considers confidential and, upon request from Landlord, Tenant shall execute a confidentiality and non-disclosure agreement reasonably acceptable to Landlord and Tenant with respect to such confidential information.

     (C) Northern Facility Budget and Schedule. Landlord shall, within a reasonable period of time, submit to Tenant a budget (“Northern Facility Budget”) for the estimated Total Northern Facility Expansion Costs (as defined below), including a sample calculation of Base Rent for the Expansion Space and a proposed construction schedule for the Northern Facility. The cost information related to the design and construction of the Northern Facility shall be shared with Tenant on a so called “open book basis”. The construction costs for the Building Shell shall not exceed the final Northern Facility Budget which Tenant shall have the right to approve (which approval shall not be unreasonably withheld, conditioned or delayed) prior to Landlord entering into the guaranteed maximum price contract with the general contractor for the Building Shell. Notwithstanding anything to the contrary contained herein, Landlord shall have the right to include a contingency of up to 8% in the Northern Facility Budget and the same 8% contingency in the guaranteed maximum price contract with the general contractor.

          The construction schedule shall include the following milestones (with Tenant acknowledging and agreeing that any failure by Tenant to make its representatives reasonably available for meetings and/or to provide information and other approvals required of Tenant shall, along with any other delays caused by Tenant and/or any Tenant Party in connection the design and construction of the Northern Facility that, with respect to any such event, (i) actually contribute to delaying (x) Landlord’s placing of Landlord’s steel order beyond the Outside Steel Order Date or (y) construction of the Building Shell beyond the Target Shell Delivery Date and (ii) continue for more than one day following Landlord’s written (or email) notice to Tenant of the matter that caused the delay, constitute a delay caused by Tenant which shall extend the dates for Landlord’s performance of the milestones noted below on a day for day basis):

     (i) on or before the date that is 9 months after the date that the parties have entered into the lease agreement or amendment for the Expansion Space (as such date may be extend by delays caused by Tenant), Landlord shall place the order for the steel for the Building Shell. If Landlord fails to timely place the order for the steel, Landlord shall not be liable to Tenant for any loss or damage resulting therefrom, and the lease with respect to the Expansion Space shall not be void or voidable except as provided for in the immediately following sentence. If, for any reason including Force Majeure (but specifically excluding any delays caused by Tenant), Landlord fails to place the order for the steel within 10.5 months after the parties have entered into the lease agreement or amendment for the Expansion Space (as extended by delays caused by Tenant, the “Outside Steel Order Date”), Tenant shall have the one time right (“Expansion Termination Right”) to terminate the lease agreement or amendment with respect to the Expansion Space and if so terminated, then, notwithstanding anything to the contrary contained herein, neither Landlord nor Tenant shall have any further rights, duties or obligations to one another with respect to the Northern Facility. If Tenant fails to deliver

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written notice to Landlord within 5 business day after the Outside Steel Order Date of its election to terminate pursuant to the provisions of the preceding sentence, Tenant shall be deemed to have forever waived its Expansion Termination Right. The parties hereby agree that, if applicable, for each day during the 1.5 month period following the expiration of the 9 month period (as such period may be extended by delays caused by Tenant) provided for in the first sentence of this paragraph until Landlord places the steel order, Tenant shall be entitled, starting on the Expansion Space Rent Commencement Date, to occupy the Expansion Space without the obligation to pay Base Rent for 1 day. If Tenant exercises the Expansion Termination Right or Landlord places the steel order prior to the expiration of such 9 month period (as such period may be extended by delays caused by Tenant) the provisions of the preceding sentence shall not apply.

     (ii) the target date for the Shell Delivery Date (as defined below) shall be 21 months after the date that the parties have entered into the lease agreement or amendment for the Expansion Space (“Target Shell Delivery Date”). If Landlord fails satisfy the requirements of the preceding sentence, Landlord shall not be liable for any loss or damage resulting therefrom but, if applicable depending on the Shell Delivery Date, the provisions of the second to last paragraph of this Section 39(a)(C) shall apply.

     The “Shell Delivery Date” shall mean the date that Tenant is notified accurately by Landlord or the general contractor for the Northern Facility that construction of the Building Shell is at a point where the Expansion Space is weather tight and is in a condition acceptable for the commencement of construction of the Expansion Space Tenant Improvements.

     Landlord shall deliver the Expansion Space to Tenant for the commencement of the construction of the Expansion Space Tenant Improvements on the Shell Delivery Date. If Landlord fails to timely deliver by the Target Shell Delivery Date, Landlord shall not be liable to Tenant for any loss or damage resulting therefrom except as expressly provided for below in this paragraph, and this Lease shall not be void or voidable. If Landlord does not deliver the Expansion Space with the Building Shell in the condition required on the Shell Delivery Date within 120 days of the Target Shell Delivery Date (as such date may be extended for Force Majeure and delays caused by Tenant and/or any Tenant Party, the “Outside Date”), Tenant shall be entitled, starting on the Expansion Space Rent Commencement Date, to occupy the Expansion Space without the obligation to pay Base Rent, 1 day for each day following the Outside Date until the Shell Delivery Date.

     Upon request of Landlord, Tenant shall execute and deliver a written acknowledgement of the Shell Delivery Date, the Expansion Space Rent Commencement Date, the Base Rent for the Expansion Space and the expiration date of the Base Term when such are established in the form substantially similar to the form of the “Acknowledgement of Commencement Date” attached to this Lease as Exhibit D; provided, however, Tenant’s failure to execute and deliver such acknowledgment shall not affect Landlord’s rights hereunder.

     Notwithstanding the foregoing, no tenant delay shall be deemed to have occurred under this Section 39 except to the extent (x) Tenant’s and/or any Tenant Parties’ action and/or inaction actually contributed to such delay beyond the applicable deadline or milestone and (y) such delay continues for more than one day following Landlord’s written (or email) notice to Tenant of the matter that caused the delay.

     (D) Base Rent for Expansion Space. The annual Base Rent for the Expansion Space shall, during the first year following the Expansion Space Rent Commencement Date, be equal to the percentage of Expansion Space relative to the rentable square footage of the Northern Facility multiplied by the product of (i) the Total Northern Facility Expansion Costs and (ii) the Annual Rate of Return; provided, however, that the monthly Base Rent for the Expansion Space shall not, during the first year following the Expansion Space Rent Commencement Date,

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exceed $3.50 per rentable square foot per month for the Expansion Space and the same shall thereafter increase as provided for in Section 4(b) on each anniversary of the Expansion Space Rent Commencement Date. For example, if the Total Northern Facility Expansion Costs equals $450 per rentable square foot, then the initial Base Rent for the Expansion Space shall be $3.38 per rentable square foot per month.

     (E) Definitions. For purposes of this Section 39(a), the following terms apply:

     (x) “Annual Rate of Return” shall mean an annual rate of return of 9%.

     (y) “Project Close-Out” is the first date following the final completion of the Building Shell by Landlord that (i) all contractors, subcontractors, suppliers, architects and others who supplied labor or materials have been paid in full; (ii) the architect or general contractor for the Northern Facility have issued any certificate(s) of completion as may be required by Landlord; and (iii) all punch list items have been completed; provided, however, that in no event shall such date be deemed to occur until the Expansion Space Rent Commencement Date.

     (z) “Total Northern Facility Expansion Costs” shall mean the sum of all of the costs incurred by Landlord through Project Close-Out in connection with the acquisition of the Northern Facility Land and the design and construction of the Northern Facility and related improvements including: (i) the purchase price allocable for Northern Facility Land (including the proposed parking structure allocated proportionately between the Northern Facility and the Project) and Landlord’s carrying costs for the Northern Facility Land (and proposed parking structure) from the time of Tenant’s delivery of the Expansion Exercise Notice through Project Close-Out, (ii) all architectural, engineering, construction, development, project management and leasing fees (consistent with other comparable projects in South San Francisco undertaken by Landlord and/or its affiliates) and all reasonable legal fees allocable to the Northern Facility (allocated proportionately to the extent such fees also relate to other portions of the Project), (iii) Landlord’s carry costs related to the Building Shell from the initiation of construction of the Building Shell and until the Expansion Space Rent Commencement Date, (iv) the $150 per rentable square foot tenant improvement allowance for the Expansion Space plus Landlord’s carry costs related to the Expansion Space Tenant Improvements from the initiation of construction of the Expansion Space Tenant Improvements until the Expansion Space Rent Commencement Date, (v) infrastructure costs, impact fees, site preparation costs, testing, labor and materials to construct the Northern Facility and related infrastructure and improvements, permit fees and any other governmental fees, sales taxes and fees payable to contractors, project landscaping, water, gas and electrical fees and related miscellaneous costs, and builder’s risk insurance and other insurance related costs (with costs described in this clause (v) allocated proportionately to the extent such costs also relate to other portions of the Project), and (vi) Landlord’s reasonable financing costs (or reasonable imputed financing costs) with respect to all of the foregoing.

     Notwithstanding the foregoing, in no event shall Total Northern Facility Expansion Costs include (A) a project management fee to Landlord for the construction of the Northern Facility in excess of 1.5% of the Total Northern Facility Expansion Costs, (B) costs due to the presence of Hazardous Materials at the Project which Tenant is not otherwise responsible for under this Lease, (C) costs to correct code violations at the Project, (D) overtime and premium time costs to complete the construction of the Northern Facility, (E) costs due to casualties (other than insurance premiums and deductibles up to $50,000 which may be included as part of Total Northern Facility Expansion Costs, (F) costs to enforce Landlord’s rights in the event of a contractor default, (G) construction costs in excess of the approved Northern Facility Budget (except for change orders requested and approved by Tenant or required by Legal Requirements

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which may be included as part of Total Northern Facility Expansion Costs), and (H) costs that in and of themselves would not otherwise have been incurred by Landlord had Tenant not elected to exercise the Expansion Right.

     (F) Tenant Default. Notwithstanding anything to the contrary contained herein, Landlord shall have the right to suspend performance of all or any of Landlord’s obligations under this Section 39 during any period that Tenant is in Default under this Lease and such period of suspension shall constitute a delay caused by Tenant; provided that Landlord has notified Tenant in writing (including email) of Landlord’s intention to suspend performance due to such Default.

     (b) Additional Expansions in Northern Facility. Provided that Landlord and Tenant have entered into a lease agreement or lease amendment for Tenant to lease the Expansion Space, Tenant shall, subject to the provisions of this Section 39(b) and (c). have the right from time to time, until the date that is 36 months after the Expansion Right Expiration Date, to elect to expand the Expansion Space (the “Right of First Offer”) to lease additional space(s) in the Northern Facility (“Additional Expansion Space”) upon the terms and conditions set forth in the immediately following paragraph; provided, however, that Landlord and Tenant can reasonably agree on the location(s) of any Additional Expansion Space but Landlord may require Tenant to lease all of the space on particular contiguous floor(s) before Tenant is permitted to lease space on any other floor. If Tenant elects to exercise the Right of First Offer, Tenant shall, on or before the date that is 36 months after Expansion Right Expiration Date, deliver written notice to Landlord of its election to lease Additional Expansion Space (“Additional Expansion Space Exercise Notice”). Tenant shall specify in each Additional Expansion Space Exercise Notice how many additional rentable square feet Tenant desires to lease. Within 10 days after Landlord’s receipt of each Additional Expansion Space Exercise Notice, Landlord shall deliver a notice (“Identification Expansion Notice”) to Tenant identifying Landlord’s proposed location of the Additional Expansion Space in the Northern Facility (“Identified Expansion Space”). Tenant shall have 5 business days after Landlord’s delivery of the Identification Expansion Notice to confirm that Tenant accepts the Identified Expansion Space as Additional Expansion Space by delivery of written notice to Landlord (“Tenant Confirmation”). If Tenant fails to deliver a Tenant Confirmation within such 5 business day period and/or no lease amendment or lease agreement for any Additional Expansion Space, acceptable to Landlord and Tenant, each in their respective reasonable discretion, has been executed and delivered by the parties within 20 days after Landlord delivers a draft of the same to Tenant despite the good faith efforts of both parties, Tenant shall be deemed to have rejected the Identified Expansion Space and Landlord shall be free, subject to the provisions of Section 39(c), to lease the Identified Expansion Space to any third party.

     Tenant acknowledges and agrees that, if Tenant accepts the Identified Expansion Space as the Additional Expansion Space by delivery of the Tenant Confirmation, Tenant shall lease such space on all of the same terms that are applicable to Tenant’s leasing of the Expansion Space, except that: (i) the term of the lease with respect to the Additional Expansion Space shall commence upon Landlord’s delivery of the Additional Expansion Space to Tenant in at least the condition required for the Shell Delivery Date to occur with respect to the Expansion Space and the term shall expire on the same date at as the term with respect to the Expansion Space, (ii) Tenant shall commence paying Base Rent (at the same per square foot rate that Tenant is then paying for the Expansion Space as the same is thereafter adjusted as provided for in this Lease) and Operating Expenses for the Additional Expansion Space immediately following the Tenant Build-Out Period for the Additional Expansion Space as such period may be extended due to Force Majeure and Landlord Delay applicable to the construction of the tenant improvements for the Additional Expansion Space, (iii) the parties shall enter into a work letter to be agreed upon by Landlord and Tenant as part of the lease agreement or lease amendment for Additional Expansion Space but which shall be substantially similar to Expansion Space Work Letter and with the same tenant improvement allowance of $150 per rentable square foot for the Additional Expansion Space for tenant improvements as provided for in the Expansion Space Work Letter; and (iv) the definitions on page 1 of the Lease will be amended as necessary to document and reflect the addition of the Additional Expansion Space and Tenant’s leasing of the Additional Expansion Space plus an increase in the Security Deposit to reflect one month of Base Rent for the Additional Expansion Space. Notwithstanding

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anything to the contrary contained herein, if applicable with respect to the Additional Expansion Space, Tenant shall be solely responsible for paying for any costs in connection with any changes which Tenant requests to the Building Shell (including, without limitation, with respect to any plans) whether or not such changes are made, and any delays in the design and/or construction of the Northern Facility caused by Tenant and/or any Tenant Party shall reduce Tenant’s Build-Out Period provided for in clause (ii) of this paragraph on a day for day basis.

     Notwithstanding anything to the contrary contained in this Section 39(b), Tenant may not elect to lease any space in the Northern Facility pursuant to this Section 39(b) if Landlord has previously delivered to Tenant a Pending Deal Notice pursuant to Section 39(c) with respect to the space in question.

     (c) Right of First Refusal. Provided that Landlord and Tenant have entered into a lease agreement or lease amendment for Tenant to lease the Expansion Space, any time prior to the date that is 36 months after the Expansion Right Expiration Date that Landlord intends to agree to a written proposal (the “Pending Deal”) to lease to any third party all or any portion of the Northern Facility which is not being leased to Tenant, not occupied by a tenant or which, subject to the provisions of the last paragraph of this Section 39(c), is occupied by an existing tenant whose lease is expiring within 6 months or less and such tenant does not wish to renew (whether or not such tenant has a right to renew) its occupancy of such space (“Right of First Refusal Space”), Landlord shall deliver to Tenant written notice (the “Pending Deal Notice”) of the existence and the terms of such Pending Deal. Tenant shall be entitled to exercise its right under this Section 39(c) only with respect to the entire space described in the Pending Deal Notice (the “Identified RFR Space”). Within 10 business days after Tenant’s receipt of the Pending Deal Notice, Tenant shall deliver to Landlord written notice (the “Space Acceptance Notice”) if Tenant elects to lease the Identified RFR Space. Tenant’s right to receive the Pending Deal Notice and election to lease or not lease the Identified RFR Space pursuant to this Section 39(c) is hereinafter referred to as the “Right of First Refusal.” If Tenant elects to lease the Identified RFR Space described in the Pending Deal Notice by delivering the Space Acceptance Notice within the required 10 business day period, Tenant shall be deemed to agree to lease the Identified RFR Space on the terms and conditions set forth in the Pending Deal Notice and any other terms as may be required by Landlord and Tenant, in their respective reasonable discretion, taking into consideration the provisions of this Lease (other than those provisions that could reasonably be considered economic and/or deal specific provisions) and the potential multi-tenant use of the Northern Facility. If (i) Tenant fails to deliver a Space Acceptance Notice to Landlord within the required 10 business day period, or (ii) no lease amendment or lease agreement for the Identified RFR Space, acceptable to Landlord and Tenant in their respective reasonable discretion, has been executed and delivered by the parties within 20 days after Landlord delivers a draft of the same to Tenant despite the good faith efforts of both parties, Tenant shall be deemed to have elected not to exercise Tenant’s right to lease the Identified RFR Space pursuant to the Pending Deal Notice in question in which case Tenant shall be deemed to have forever waived its right to lease the Identified RFR Space pursuant to the Pending Deal Notice in question, this Section 39(c) shall terminate and be of no further force or effect with respect to the Pending Deal Notice in question, and Landlord shall have the right to lease the Identified RFR Space to the party that was the subject of the Pending Deal Notice on substantially the business terms and conditions set forth in the Pending Deal Notice. Notwithstanding the foregoing, if Landlord negotiates with the proposed tenant economic lease terms materially more favorable (but in no event shall the economic lease terms be considered materially more favorable unless the other proposed tenant is offered a base rental rate, tenant improvement allowance, lease term and/or a free rent period more favorable than was offered to Tenant), as reasonably determined by Landlord, than those offered to Tenant but rejected as part of the Pending Deal Notice, Landlord shall be required to submit the more favorable economic terms to Tenant for its review. Tenant shall have 7 business days after receipt of the more favorable economic terms to accept or reject the revised terms. If Tenant rejects the more favorable terms, Landlord shall be free to enter into a lease with the proposed tenant on such terms. The Right of First Refusal shall be continuous during the period set forth in the first sentence of this Section 39(c). Tenant’s rejection of any particular Pending Deal Notice shall not relieve Landlord of its obligation to again offer any Right of First Refusal Space to Tenant at any time that Landlord intends, subject to the provisions of the first sentence of this Section 39(c) with

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respect to an existing tenant extending the term of its lease, to again agree to a written proposal from another party to lease such space in such period.

     Notwithstanding anything to the contrary contained herein, (i) in no event shall Landlord be required to disclose to Tenant the name of any party with whom Landlord intends to agree to a Pending Deal, and (ii) during the period that Tenant’s Right of First Refusal is in effect, in no event may Landlord agree to the extension of the term of a lease with a tenant in the Northern Facility beyond the term (including any proposed extensions) set forth in the applicable Pending Deal Notice delivered to Tenant with respect to such tenant’s premises without giving Tenant the right to lease such space pursuant to the terms of this Section 39(c).

     (d) Exceptions. Notwithstanding the above, the Expansion Right, Right of First Offer and the Right of First Refusal shall, at Landlord’s option, not be in effect and may not be exercised by Tenant:

     (i) during any period of time that Tenant is in Default under any provision of the Lease; or

     (ii) if Tenant has been in Default under any provision of the Lease 3 or more times, whether or not the Defaults are cured, during the 12 month period prior to the date on which Tenant seeks to exercise the Expansion Right, Right of First Offer or Right of First Refusal, as applicable.

     (e) Termination. The Expansion Right, Right of First Offer and Right of First Refusal, as applicable, shall, at Landlord’s option, terminate and be of no further force or effect even after Tenant’s due and timely exercise of the Expansion Right, Right of First Offer or Right of First Refusal, as applicable, if, after such exercise, but prior to the commencement date of the lease of such Expansion Space, Additional Expansion Space or Identified RFR Space, as applicable, (i) Tenant fails to timely cure any default by Tenant under the Lease; or (ii) Tenant has Defaulted 3 or more times during the period from the date of the exercise of the Expansion Right, Right of First Offer or Right of First Refusal, as applicable, to the date of the commencement of the lease of the Expansion Space, Additional Expansion Space or Identified RFR Space, as applicable, whether or not such Defaults are cured.

     (f) Rights Personal. The Expansion Right, Right of First Offer and Right of First Refusal are personal to Tenant and are not assignable without Landlord’s consent, which may be granted or withheld in Landlord’s sole discretion separate and apart from any consent by Landlord to an assignment of Tenant’s interest in the Lease except that they may be assigned in connection with any Permitted Assignment of this Lease.

     (g) No Extensions. The period of time within which the Expansion Right, Right of First Offer or Right of First Refusal may be exercised shall not be extended or enlarged for any reason. The parties acknowledge that the time period for Tenant’s response to a Pending Deal Notice is only triggered when Tenant receives such Pending Deal Notice.

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

     (a) Extension Rights. Tenant shall have 2 consecutive rights (each, an “Extension Right”) to extend the term of this Lease for 5 years each (each, an “Extension Term”) on the same terms and conditions as this Lease (other than with respect to Base Rent and the Work Letter) by giving Landlord written notice of its election to exercise each Extension Right at least 9 months prior, and no earlier than 12 months prior, to the expiration of the Base Term of the Lease or the expiration of any prior Extension Term.

     Upon the commencement of any Extension Term, Base Rent shall be payable at the Market Rate (as defined below). Base Rent shall thereafter be adjusted on each annual anniversary of the

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commencement of such Extension Term by a percentage as agreed to by Landlord and Tenant at the time the Market Rate is determined. As used herein, “Market Rate” shall mean the then market rental rate as agreed to by Landlord and agreed to by Tenant. In addition, Landlord may impose a market rent for the parking rights provided hereunder; provided, however, that Landlord shall not charge rent for parking rights during any Extension Term unless Landlord is required to do so by any Governmental Authority or as part of a traffic mitigation or similar such plan.

     If, on or before the date which is 180 days prior to the expiration of the Base Term of this Lease, or the expiration of any prior Extension Term, as applicable, Landlord and Tenant have not agreed upon the Market Rate and the rent escalations during the applicable Extension Term after negotiating in good faith, Tenant shall be deemed to have elected arbitration as described in Section 40(b). If Tenant has elected to exercise the Extension Right by delivering notice to Landlord as required in this Section 40(a), Tenant shall have no right thereafter to rescind or elect not to extend the term of the Lease for the Extension Term and Landlord shall be obligated to extend the Term of this Lease for the Extension Term.

     (b) Arbitration.

     (i) Within 10 days of Tenant’s notice to Landlord of its election (or deemed election) to arbitrate Market Rate and escalations, each party shall deliver to the other a proposal containing the Market Rate and escalations that the submitting party believes to be correct (“Extension Proposal”). If either party fails to timely submit an Extension Proposal, the other party’s submitted proposal shall determine the Base Rent and escalations for the Extension Term. If both parties submit Extension Proposals, then Landlord and Tenant shall meet within 7 days after delivery of the last Extension Proposal and make a good faith attempt to mutually appoint a single Arbitrator (and defined below) to determine the Market Rate and escalations. If Landlord and Tenant are unable to agree upon a single Arbitrator, then each shall, by written notice delivered to the other within 10 days after the meeting, select an Arbitrator. If either party fails to timely give notice of its selection for an Arbitrator, the other party’s submitted proposal shall determine the Base Rent and any escalations for the Extension Term. The 2 Arbitrators so appointed shall, within 5 business days after their appointment, appoint a third Arbitrator. If the 2 Arbitrators so selected cannot agree on the selection of the third Arbitrator within the time above specified, then either party, on behalf of both parties, may request such appointment of such third Arbitrator by application to any state court of general jurisdiction in the jurisdiction in which the Premises are located, upon 10 days prior written notice to the other party of such intent.

     (ii) The decision of the Arbitrator(s) shall be made within 30 days after the appointment of a single Arbitrator or the third Arbitrator, as applicable. The decision of the single Arbitrator shall be final and binding upon the parties. The average of the two closest Arbitrators in a three Arbitrator panel shall be final and binding upon the parties. Each party shall pay the fees and expenses of the Arbitrator appointed by or on behalf of such party and the fees and expenses of the third Arbitrator shall be borne equally by both parties. If the Market Rate and escalations are not determined by the first day of the Extension Term, then Tenant shall pay Landlord Base Rent in an amount equal to the Base Rent in effect immediately prior to the Extension Term and increased by the Rent Adjustment Percentage until such determination is made. After the determination of the Market Rate and escalations, the parties shall make any necessary adjustments to such payments made by Tenant. Landlord and Tenant shall then execute an amendment recognizing the Market Rate and escalations for the Extension Term.

     (iii) An “Arbitrator” shall be any person appointed by or on behalf of either party or appointed pursuant to the provisions hereof and: (i) shall be (A) a member of the American Institute of Real Estate Appraisers with not less than 10 years of experience in the appraisal of improved office and high tech industrial real estate in the greater South San Francisco area, or (B) a licensed commercial real estate broker with not less than 15 years experience representing landlords and/or tenants in the leasing of high tech or life sciences space in the greater South San Francisco area, (ii) devoting substantially all of their time to professional appraisal or

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brokerage work, as applicable, at the time of appointment and (iii) be in all respects impartial and disinterested.

     (c) Rights Personal. Extension Rights are personal to Tenant and are not assignable without Landlord’s consent, which may be granted or withheld in Landlord’s sole discretion separate and apart from any consent by Landlord to an assignment of Tenant’s interest in the Lease, except that they may be assigned in connection with any Permitted Assignment of this Lease.

     (d) Exceptions. Notwithstanding anything set forth above to the contrary, Extension Rights shall not be in effect and Tenant may not exercise any of the Extension Rights:

     (i) during any period of time that Tenant is in Default under any provision of this Lease; or

     (ii) if Tenant has been in Default under any provision of this Lease 3 or more times, whether or not the Defaults are cured, during the 12 month period immediately prior to the date that Tenant intends to exercise an Extension Right, whether or not the Defaults are cured.

     (e) No Extensions. The period of time within which any Extension Rights may be exercised shall not be extended or enlarged for any reason.

     (f) Termination. The Extension Rights shall terminate and be of no further force or effect even after Tenant’s due and timely exercise of an Extension Right, if, after such exercise, but prior to the commencement date of an Extension Term, (i) Tenant fails to timely cure any default by Tenant under this Lease; or (ii) Tenant has Defaulted 3 or more times during the period from the date of the exercise of an Extension Right to the date of the commencement of the Extension Term, whether or not such Defaults are cured.

     41. Additional Premises. As of the date of this Lease, the balance of the Building, consisting of the third and fourth floors and the server room on the first floor of the Building containing a total of approximately 71,746 rentable square feet (the “Additional Space”), is subject to that certain Lease Agreement between Landlord and Exelixis, Inc., a Delaware corporation (“Exelixis”),dated as of September 14, 2007 (as the same may have been or may in the future be amended, the “Exelixis Lease”). Tenant shall have the right to occupy the Additional Space (other than the server room) as of the Commencement Date pursuant to a sublease agreement between Exelixis and Tenant (the “Exelixis Sublease”), which Exelixis Sublease shall be subject to Landlord’s written consent. Landlord and Tenant hereby agree that, so long as this Lease remains in full force and effect at the expiration of the Exelixis Lease, which is scheduled to occur on November 30, 2015, then, commencing on December 1, 2015 (“AP Commencement Date”), the Premises shall be automatically expanded to include the Additional Space and the Additional Space shall be subject to all of the terms and conditions of this Lease; provided, however, that as of the AP Commencement Date, (a) the Rentable Area of Premises shall be increased to 129,501 rentable square feet, (b) Tenant shall be required to pay Base Rent for the Additional Space at the same per square foot rate of Base Rent then being paid by Tenant with respect to the original Premises, (c) Tenant’s Share of Operating Expenses of Building shall be increased to 100%, (d) Tenant’s Share of Operating Expenses of the Project shall be proportionately adjusted, subject to further adjustment pursuant to the last paragraph of Section 5, and (e) Tenant shall accept the Additional Space in its then as is condition and Landlord shall not be obligated to make any tenant improvements to the Additional Space or provide Tenant with any tenant improvement allowance. Notwithstanding anything to the contrary in this Lease, this Lease is expressly conditioned upon the occurrence of the following concurrent with the mutual execution and delivery of this Lease by Landlord and Tenant: (i) the execution and delivery by and between Exelixis and Tenant of the Exelixis Sublease on terms and conditions acceptable to Tenant, and (ii) Landlord’s written consent to the Exelixis Sublease, which consent shall contain Landlord’s agreement that (a) Tenant’s continued occupancy of the Additional Space following November 30, 2015, shall be pursuant to this Lease and shall not constitute a holdover under the Exelixis

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Lease and (b) Exelixis shall have no obligation to remove or restore any existing alterations in the Additional Space or to remove or restore any Tenant Improvements.

     Notwithstanding the foregoing, Landlord agrees that if the Exelixis Lease terminates prior to November 30, 2015, then, notwithstanding anything to the contrary contained in this Lease, the AP Commencement Date shall be amended to be the day immediately after the date of such early termination of the Exelixis Lease (“Early AP Commencement Date”); provided, however, that (i) Tenant shall, commencing on the later of the Early AP Commencement Date and the Start Date (as defined in the Sublease) through November 30, 2015, be required to (a) pay Base Rent in the amount provided for in the Sublease which shall in no event be less than the amount of $111,699.25 per month as increased by 3% on each anniversary of the Start Date, plus base rent for 3,008 rentable square foot server room on the first floor of the Building at the same base rent that is then being paid on a per square foot basis under the Sublease for the balance of the Additional Space (as the same is adjusted by the annual 3% increases), and (b) Tenant’s Share of Operating Expenses of the Building and the Project (as the same may be adjusted as provided for in this Lease) with respect to the Additional Space (i.e. 55.4% for the balance of the Building) and (ii) if the Exelixis Lease has terminated due to a casualty or condemnation, such casualty or condemnation shall be deemed to have occurred during the Base Term of this Lease and the rights and obligations of Landlord and Tenant with respect to this Lease shall be governed by Section 18 or Section 19 of this Lease, as applicable.

     42. Miscellaneous.

     (a) Notices. All notices or other communications between the parties shall be in writing and shall be deemed duly given upon delivery or refusal to accept delivery by the addressee thereof if delivered in person, or upon actual receipt if delivered by reputable overnight guaranty courier, addressed and sent to the parties at their addresses set forth above. Landlord and Tenant may from time to time by written notice to the other designate another address for receipt of future notices.

     (b) Joint and Several Liability. If and when included within the term “Tenant,” as used in this instrument, there is more than one person or entity, each shall be jointly and severally liable for the obligations of Tenant.

     (c) Financial Information. Upon Landlord’s request, Tenant shall furnish Landlord with true and complete copies of (i) Tenant’s most recent audited annual financial statements within 90 days of the end of each of Tenant’s fiscal years during the Term, (ii) Tenant’s most recent unaudited quarterly financial statements within 45 days of the end of each of Tenant’s first three fiscal quarters of each of Tenant’s fiscal years during the Term, (iii) at Landlord’s request from time to time, updated business plans, including cash flow projections and/or pro forma balance sheets and income statements, all of which shall be treated by Landlord as confidential information belonging to Tenant, (iv) corporate brochures and/or profiles prepared by Tenant for prospective investors, and (v) any other financial information or summaries that Tenant typically provides to its lenders or shareholders. So long as Tenant is a “public company” and its financial information is publicly available, then the foregoing delivery requirements of this Section 42(c) shall not apply.

     (d) Recordation. Neither this Lease nor a memorandum of lease shall be filed by or on behalf of Tenant in any public record. Landlord may prepare and file, and upon request by Landlord Tenant will execute, a memorandum of lease.

     (e) Interpretation. The normal rule of construction to the effect that any ambiguities are to be resolved against the drafting party shall not be employed in the interpretation of this Lease or any exhibits or amendments hereto. Words of any gender used in this Lease shall be held and construed to include any other gender, and words in the singular number shall be held to include the plural, unless the context otherwise requires. The captions inserted in this Lease are for convenience only and in no way define, limit or otherwise describe the scope or intent of this Lease, or any provision hereof, or in any way affect the interpretation of this Lease.

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

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

     (h) Choice of Law. Construction and interpretation of this Lease shall be governed by the internal laws of the state in which the Premises are located, excluding any principles of conflicts of laws.

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

     (j) OFAC. Tenant, and to Tenant’s knowledge, all beneficial owners of Tenant, are currently (a) in compliance with and shall at all times during the Term of this Lease remain in compliance with the regulations of the Office of Foreign Assets Control (“OFAC”) of the U.S. Department of Treasury and any statute, executive order, or regulation relating thereto (collectively, the “OFAC Rules”), (b) not listed on, and shall not during the term of this Lease be listed on, the Specially Designated Nationals and Blocked Persons List maintained by OFAC and/or on any other similar list maintained by OFAC or other governmental authority pursuant to any authorizing statute, executive order, or regulation, and (c) not a person or entity with whom a U.S. person is prohibited from conducting business under the OFAC Rules.

     (k) Incorporation by Reference. All exhibits and addenda attached hereto are hereby incorporated into this Lease and made a part hereof. If there is any conflict between such exhibits or addenda and the terms of this Lease, such exhibits or addenda shall control.

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

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

     (n) Hazardous Activities. Notwithstanding any other provision of this Lease, Landlord, for itself and its employees, agents and contractors, reserves the right to refuse to perform any repairs or services in any portion of the Premises which, pursuant to Tenant’s routine safety guidelines, practices or custom or prudent industry practices, require any form of protective clothing or equipment other than safety glasses. In any such case, Tenant shall contract with parties who are acceptable to Landlord, in Landlord’s reasonable discretion, for all such repairs and services, and Landlord shall, to the extent

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required, equitably adjust Tenant’s Share of Operating Expenses in respect of such repairs or services to reflect that Landlord is not providing such repairs or services to Tenant.

     (o) Construction of Remainder of Project. Tenant acknowledges that Landlord intends to construct other buildings at the Project in the future and that the same may adversely impact Tenant’s access to and use of the Project. In constructing additional improvements on the Project, Landlord shall endeavor to minimize disturbance to Tenant’s use of the Premises and/or Tenant’s parking rights.

     (p) Roof Equipment. Subject to the provisions of this Lease, during the Term, Tenant may, at its sole cost, install, maintain, and from time to time replace mechanical, security and/or process equipment on the roof of the Building (collectively, “Roof Equipment”), at no additional rental expense to Tenant (other than reimbursing Landlord for any costs reasonably incurred by Landlord in connection with the exercise by Tenant of any rights granted to Tenant under this Section 42(p)); provided, however, that (i) Tenant shall obtain Landlord’s prior written approval of the proposed size, weight and location of the Roof Equipment and method for fastening the same to the roof, (ii) Tenant shall, at its sole cost, comply with reasonable requirements imposed by Landlord and all Legal Requirements and the conditions of any bond or warranty maintained by Landlord on the roof, (iii) Tenant shall be responsible for paying for any structural upgrades that may be reasonably required by Landlord in connection with the Roof Equipment, and (iv) Tenant shall remove, at its expense, at the expiration or earlier termination of this Lease, any Roof Equipment which Landlord requires to be removed at the time Landlord consents to the installation of such equipment, other than Roof Equipment installed as part of the Tenant Improvements, which may be surrendered by Tenant. Landlord shall have the right to supervise any roof penetration. Tenant shall repair any damage to the Building caused by Tenant’s installation, maintenance, replacement, use or removal of the Roof Equipment. Tenant shall install, use, maintain and repair the Roof Equipment, and use the access areas, so as not to damage or interfere with the operation of the Building or with the occupancy or activities of any other tenant of the Building. Landlord shall give Tenant written notice and 30 days to cure such interference before requiring Tenant to remove any Roof Equipment. Tenant shall protect, defend, indemnify and hold harmless Landlord from and against claims, damages, liabilities, costs and expenses of every kind and nature, including attorneys’ fees, incurred by or asserted against Landlord arising out of Tenant’s installation, maintenance, replacement, use or removal of the Roof Equipment except to the extent caused by the willful misconduct or negligence of Landlord or the default by Landlord in the performance of its obligations under this Lease. Tenant’s right to use the roof as contemplated in this Section 41(p) shall be non-exclusive with any other tenant(s) in the Building until and during such time as Tenant leases the entire Building.

     (q) Hazardous Materials Storage Area. In connection with its use of the Premises, Tenant shall have the right, during the Term, to the use of certain space designated by Landlord on Exhibit J for the storage of chemicals, Hazardous Materials waste and other Hazardous Materials (“HazMat Safety Storage Area”). Tenant shall maintain appropriate records, obtain and maintain appropriate insurance, implement reporting procedures, and take or cause to be taken all other actions necessary or required under applicable state and federal Legal Requirements in connection with the use of the HazMat Safety Storage Area. Tenant shall surrender the HazMat Safety Storage Area in accordance with the requirements of Section 28 hereof.

     (r) New Generator. In connection with its the use of the Premises, Tenant may install an emergency generator (a “New Generator”) as part of the Tenant Improvements, in a location shown on Exhibit J, and if such New Generator is installed as part of the Tenant Improvements and paid for out of the Tl Allowance, the New Generator shall be the property of Landlord and may not be removed by Tenant. Tenant shall reimburse Landlord for any costs reasonably incurred by Landlord in connection with the exercise by Tenant of any rights granted to Tenant under this Section 42(r). Tenant shall, at its sole cost, comply with reasonable requirements imposed by Landlord and all Legal Requirements. Landlord shall have the right to supervise the installation of the New Generator. Tenant shall protect, defend, indemnify and hold harmless Landlord from and against claims, damages, liabilities, costs and expenses of every kind and nature, including attorneys’ fees, incurred by or asserted against Landlord arising out of Tenant’s installation, maintenance and/or use of the New Generator except to the extent

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caused by the willful misconduct or negligence of Landlord or the default by Landlord in the performance of its obligations under this Lease.

     (s) Existing Exelixis Generator. Tenant acknowledges that the existing emergency generator being used by Exelixis and located in the area shown Exhibit J (“Existing Generator”) is the property of Landlord and the same may not be removed by Tenant. Tenant shall have the right to maintain and use the Existing Generator following the expiration or earlier termination of the Exelixis Lease; provided, however, that Tenant shall protect, defend, indemnify and hold harmless Landlord from and against claims, damages, liabilities, costs and expenses of every kind and nature, including attorneys’ fees, incurred by or asserted against Landlord arising out of Tenant’s maintenance and/or use of the Existing Generator except to the extent caused by the willful misconduct or negligence of Landlord or the default by Landlord in the performance of its obligations under this Lease.

     (t) Patio Area. In connection with its use of the Premises, Tenant shall have the exclusive right to use the outdoor patio area to be shown in an area to be mutually approved by the parties on the Tl Construction Drawings (“Patio Area”); provided, however, that in all respects such Patio Area complies with all present and/or future approvals granted by the City of South San Francisco and all other Legal Requirements and rules and regulations applicable to the Project. Subject to the provisions of this Section 42(t), Tenant may place furniture outside of the Premises in the Patio Area. Tenant shall have all of the same obligations with respect to the Patio Area that Tenant has under this Lease with respect to the Premises, except that Tenant shall not be required to pay additional Base Rent with respect to any Patio Area. Tenant shall, at Tenant’s sole cost and expense, shall maintain any such Patio Area free of trash and debris. Tenant’s right to the Patio Area is neither transferable nor assignable except together with this Lease.

[Signatures on next page]

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

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		249 E. Grand/Onyx — Page 1

EXHIBIT A TO LEASE

DESCRIPTION OF PREMISES

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		249 E. Grand/Onyx — Page 2

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EXHIBIT B TO LEASE

DESCRIPTION OF PROJECT

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Work Letter — Tenant Build		249 E. Grand/Onyx — Page 1

EXHIBIT C TO LEASE

WORK LETTER

     THIS WORK LETTER (this “Work Letter”) is incorporated into that certain Lease Agreement (the “Lease”) dated as of July 9, 2010 by and between ARE-SAN FRANCISCO NO. 12, LLC, a Delaware limited liability company (“Landlord”), and ONYX PHARMACEUTICALS, INC., a Delaware corporation (“Tenant”). Any initially capitalized terms used but not defined herein shall have the meanings given them in the Lease.

     1.   General Requirements.

     (a) Tenant’s Authorized Representative. Tenant designates David Benjamin and Matthew K. Fust (either such individual acting alone, “Tenant’s Representative”) as the only persons authorized to act for Tenant pursuant to this Work Letter. Landlord shall not be obligated to respond to or act upon any request, approval, inquiry or other communication (“Communication”) from or on behalf of Tenant in connection with this Work Letter unless such Communication is in writing from Tenant’s Representative. Tenant may change either Tenant’s Representative at any time upon not less than 5 business days advance written notice to Landlord.

     (b) Landlord’s Authorized Representative. Landlord designates Stephen Richardson and Greg Gehlen (either such individual acting alone, “Landlord’s Representative”) as the only persons authorized to act for Landlord pursuant to this Work Letter. Tenant shall not be obligated to respond to or act upon any request, approval, inquiry or other Communication from or on behalf of Landlord in connection with this Work Letter unless such Communication is in writing from Landlord’s Representative. Landlord may change either Landlord’s Representative at any time upon not less than 5 business days advance written notice to Tenant.

     (c) Architects, Consultants and Contractors. Landlord and Tenant hereby acknowledge and agree that the architect (the “TI Architect”) for the Tenant Improvements (as defined in Section 2(a) below), the general contractor and any subcontractors for the Tenant Improvements shall be selected by Tenant, subject to Landlord’s approval, which approval shall not be unreasonably withheld, conditioned or delayed. Landlord shall be named a third party beneficiary of any contract entered into by Tenant with the TI Architect, any consultant, any contractor or any subcontractor, and of any warranty made by any contractor or any subcontractor. Landlord hereby approves of DGA Architects as Tenant’s architect and any of BNBuilders, Landmark Construction or XL Construction as Tenant’s contractor.

     2. Tenant Improvements.

     (a) Tenant Improvements Defined. As used herein, “Tenant Improvements” shall mean all improvements to the Building (including the roof and outdoor areas serving the Building) desired by Tenant of a fixed and permanent nature. Other than funding the TI Allowance (as defined below) as provided herein and as otherwise expressly set forth in this Lease, Landlord shall not have any obligation whatsoever with respect to the finishing of the Premises for Tenant’s use and occupancy.

     (b) Tenant’s Space Plans. Tenant shall deliver to Landlord schematic drawings and outline specifications (the “TI Design Drawings”) detailing Tenant’s requirements for the Tenant Improvements within 30 days of the date hereof. Not more than 7 days thereafter, Landlord shall deliver to Tenant the written objections, questions or comments of Landlord and the TI Architect with regard to the TI Design Drawings. Tenant shall cause the TI Design Drawings to be revised to address such written comments and shall resubmit said drawings to Landlord for approval within 30 days thereafter. Such process shall continue until Landlord has approved the TI Design Drawings. Subject to the provisions of this Section 2, Landlord approves of the Tenant Improvements as described in Schedule 1 of this Work Letter and shall not unreasonably withhold its consent to the TI Design Drawings or TI Construction Drawings to the

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Work Letter — Tenant Build		249 E. Grand/Onyx — Page 2

extent consistent therewith. Landlord shall respond to any request for approval in this Work Letter within the time period set forth herein, or if no time period is specified, within 5 business days. If Landlord fails to respond within the required time period, Tenant may submit a second written request to Landlord for approval which notice shall specifically describe the approval being sought and state that Landlord’s failure to respond within 5 business days shall be deemed to constitute Landlord’s approval of the matter in question and that from the date Landlord’s approval was due until the earlier of Landlord’s response or the expiration of such 5 business day period shall constitute a Landlord Delay (as defined below); provided, however, that in no event shall the Landlord Delay actually commence unless and until Landlord’s receives written notice from Tenant notifying Landlord of the existence of such Landlord Delay.

     (c) Working Drawings. Not later than 15 business days following the approval of the TI Design Drawings by Landlord, Tenant shall cause the TI Architect to prepare and deliver to Landlord for review and comment construction plans, specifications and drawings for the Tenant Improvements (“TI Construction Drawings”), which TI Construction Drawings shall be prepared substantially in accordance with the TI Design Drawings. Tenant shall be solely responsible for ensuring that the TI Construction Drawings reflect Tenant’s requirements for the Tenant Improvements. Landlord shall deliver its written comments on the TI Construction Drawings to Tenant not later than 10 business days after Landlord’s receipt of the same; provided, however, that Landlord may not disapprove any matter that is consistent with the TI Design Drawings. Tenant and the TI Architect shall consider all such comments in good faith and shall, within 10 business days after receipt, notify Landlord how Tenant proposes to respond to such comments. Any disputes in connection with such comments shall be resolved in accordance with Section 2(d) hereof. Provided that the design reflected in the TI Construction Drawings is consistent with the TI Design Drawings or otherwise reasonably approved by Landlord, Landlord shall approve the TI Construction Drawings submitted by Tenant. Once approved by Landlord, subject to the provisions of Section 4 below, Tenant shall not materially modify the TI Construction Drawings except as may be reasonably required in connection with the issuance of the TI Permit (as defined in Section 3(a) below).

     (d) Approval and Completion. If any dispute regarding the design of the Tenant Improvements is not settled within 10 business days after notice of such dispute is delivered by one party to the other, Tenant may make the final decision regarding the design of the Tenant Improvements, provided (i) Tenant acts reasonably and such final decision is either consistent with or a compromise between Landlord’s and Tenant’s positions with respect to such dispute, (ii) that all costs and expenses resulting from any such decision by Tenant shall be payable out of the TI Allowance (as defined in Section 5(d) below) or otherwise by Tenant, and (iii) Tenant’s decision will not affect the base Building, structural components of the Building or any Building systems (in which case Landlord shall make the final decision). Any changes to the TI Construction Drawings following Landlord’s and Tenant’s approval of same requested by Tenant shall be processed as provided in Section 4 hereof.

     (e)  No Obligation to Build Tenant Improvements. Notwithstanding anything to the contrary in this Work Letter, Tenant’s failure to design or construct the Tenant Improvements or meet any of the time periods set forth in this Work Letter for construction of the Tenant Improvements shall not be a default under this Lease. Other than with respect to Landlord Delay as provided for in this Work Letter, nothing contained in this Work Letter shall delay the Rent Commencement Date.

      3. Performance of the Tenant Improvements.

     (a) Commencement and Permitting of the Tenant Improvements. Tenant shall commence construction of the Tenant Improvements upon obtaining and delivering to Landlord a building permit (the “TI Permit”) authorizing the construction of the Tenant Improvements consistent with the TI Construction Drawings approved by Landlord. The cost of obtaining the TI Permit shall be payable from the TI Allowance. Landlord shall assist Tenant in obtaining the TI Permit. Prior to the commencement of the Tenant Improvements, Tenant shall deliver to Landlord a copy of any contract with Tenant’s contractors (including the TI Architect), and certificates of insurance from any contractor performing any part of the Tenant Improvement evidencing industry standard commercial general liability, automotive

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Work Letter — Tenant Build		249 E. Grand/Onyx — Page 3

liability, “builder’s risk”, and workers’ compensation insurance. Tenant shall cause the general contractor to provide a certificate of insurance naming Landlord, Alexandria Real Estate Equities, Inc., and Landlord’s lender (if any) as additional insureds for the general contractor’s liability coverages required above.

     (b) Selection of Materials, Etc. Where more than one type of material or structure is indicated on the TI Construction Drawings approved by Tenant and Landlord, the option will be within Tenant’s reasonable discretion if the matter concerns the Tenant Improvements, and within Landlord’s reasonable discretion if the matter concerns the structural components of the Building or any Building system.

     (c) Tenant Liability. Tenant shall be responsible for correcting any deficiencies or defects in the Tenant Improvements.

     (d) Substantial Completion. Tenant shall substantially complete or cause to be substantially completed the Tenant Improvements in a good and workmanlike manner, in accordance with the TI Permit subject, in each case, to Minor Variations and normal “punch list” items of a non-material nature which do not interfere with the use of the Premises (“Substantial Completion” or “Substantially Complete”). Upon Substantial Completion of the Tenant Improvements, Tenant shall require the TI Architect and the general contractor to execute and deliver, for the benefit of Tenant and Landlord, a Certificate of Substantial Completion in the form of the American Institute of Architects (“AIA”) document G704. For purposes of this Work Letter, “Minor Variations” shall mean any modifications reasonably required: (i) to comply with all applicable Legal Requirements and/or to obtain or to comply with any required permit (including the TI Permit); (ii) to comport with good design, engineering, and construction practices which are not material; or (iii) to make reasonable adjustments for field deviations or conditions encountered during the construction of the Tenant Improvements.

     (e) Landlord Delay. As provided for in Section 2 of the Lease, the Outside Date shall be extended one day for each day that Substantial Completion of the Tenant Improvements is delayed due to Landlord Delay. As used herein, “Landlord Delay” shall mean any delay or failure to act by Landlord after the date hereof (other than a matter which qualifies as a Force Majeure or a delay by Tenant) within the time period required for such action pursuant to this Work Letter (or if no period is provided for then within a reasonable period of time after written request to Landlord from Tenant) which delay or failure actually causes or results in a delay in Substantial Completion of the Tenant Improvements. The general contractor for the Tenant Improvements shall make the determination regarding the date on which Substantial Completion of the Tenant Improvements would have occurred but for such Landlord Delay; provided, however, that Landlord may challenge such determination by naming an architect or general contractor reasonably acceptable to Tenant to make a final determination as to the Landlord Delay, if any. In no event shall a Landlord Delay commence unless and until Landlord receives written notice from Tenant notifying Landlord of the existence of such Landlord Delay.

     4. Changes. Any changes requested by Tenant to the Tenant Improvements after the delivery and approval by Landlord of the TI Design Drawings, shall be requested and instituted in accordance with the provisions of this Section 4 and shall be subject to the written approval of Landlord, which approval shall not be unreasonably withheld, conditioned or delayed.

     (a) Tenant’s Right to Request Changes. If Tenant shall request changes (“Changes”), Tenant shall request such Changes by notifying Landlord in writing in substantially the same form as the AIA standard change order form (a “Change Request”), which Change Request shall detail the nature and extent of any such Change. Such Change Request must be signed by Tenant’s Representative. Landlord shall review and approve or disapprove such Change Request within 5 business days thereafter, provided that Landlord’s approval shall not be unreasonably withheld, conditioned or delayed.

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Work Letter — Tenant Build		249 E. Grand/Onyx — Page 4

     (b) Implementation of Changes. If Landlord approves such Change, Tenant may cause the approved Change to be instituted. If any TI Permit modification or change is required as a result of such Change, Tenant shall promptly provide Landlord with a copy of such TI Permit modification or change.

     5. Costs.

     (a) Budget For Tenant Improvements. Before the commencement of construction of the Tenant Improvements, Tenant shall obtain a detailed breakdown, by trade, of the costs incurred or that will be incurred, in connection with the design and construction of the Tenant Improvements (the “Budget”), and deliver a copy of the Budget to Landlord for Landlord’s approval, which shall not be unreasonably withheld or delayed and shall be given within five (5) business days of delivery thereof by Tenant. The Budget shall be based upon the TI Construction Drawings approved by Landlord.

     (b) TI Allowance. Landlord shall provide to Tenant a tenant improvement allowance (collectively, the “TI Allowance”) as follows:

     1. a “Tenant Improvement Allowance” in the amount of $193.46 per rentable square foot in the Premises, which is included in the Base Rent set forth in the Lease; and

     2. an “Additional Tenant Improvement Allowance” in the maximum amount of $20.00 per rentable square foot in the Premises, which shall, to the extent used, result in adjustments to the Base Rent as set forth in the Lease.

     For the avoidance of any doubt, although the TI Allowance may be used for Tenant Improvements throughout the Building (including the roof and outdoor areas serving the Building), the TI Allowance is only calculated upon the square footage of the original Premises consisting of 57,755 rentable square feet and not any other portion of the Project. If Tenant does not elect to use any of the Additional Tenant Improvement Allowance, then references to TI Allowance herein, shall mean the Tenant Improvement Allowance.

     Before commencing the Tenant Improvements, Tenant shall notify Landlord how much Additional Tenant Improvement Allowance Tenant has elected to receive from Landlord. Tenant may adjust such amount from time to time during the course of construction of the Tenant Improvements. The TI Allowance shall be disbursed in accordance with this Work Letter.

     Tenant shall have no right to the use or benefit (including any reduction to Base Rent) of any portion of the TI Allowance not required for the construction of (i) the Tenant Improvements described in the TI Construction Drawings approved pursuant to Section 2(d) or (ii) any Changes pursuant to Section 4. Tenant shall have no right to any portion of the TI Allowance that is not disbursed before December 31, 2011. Notwithstanding the foregoing, any portions of the Tenant Improvement Allowance not used by Tenant in constructing the Tenant Improvements may be used for Alterations of a fixed and permanent nature to the Building after the Rent Commencement Date but prior to December 31, 2011.

     (c) Costs Includable in TI Allowance. The TI Allowance shall be used solely for the payment of design, permits and construction costs in connection with the construction of the Tenant Improvements, including, without limitation, the cost of electrical power and other utilities used in connection with the construction of the Tenant Improvements, the cost of preparing the TI Design Drawings and the TI Construction Drawings and the cost of Tenant’s project manager, all costs set forth in the Budget and the cost of Changes (collectively, “TI Costs”). Notwithstanding anything to the contrary contained herein, the TI Allowance (whether used for the Tenant Improvements and/or Alterations) shall not be used to purchase any furniture, personal property or other non-Building system materials or equipment, including, but not limited to, Tenant’s voice or data cabling, non-ducted biological safety

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Work Letter — Tenant Build		249 E. Grand/Onyx — Page 5

cabinets and other scientific equipment not incorporated into the Tenant Improvements but may be used for Tenant’s clean dry air and deionized water systems and Roof Equipment.

     (d) Excess TI Costs. Landlord shall have no obligation to bear any portion of the cost of any of the Tenant Improvements except to the extent of the TI Allowance. Notwithstanding anything to the contrary set forth in this Section 5(d), Tenant shall be fully and solely liable for TI Costs and the cost of Minor Variations in excess of the TI Allowance. Notwithstanding the foregoing or anything to the contrary in this Lease, Landlord shall be responsible, at its sole cost and not as part of the TI Allowance, for any work required and costs incurred as part of the construction of the Tenant Improvements due to the presence of Hazardous Materials located on or about the Project prior to the date of this Lease.

     (e) Payment for TI Costs. During the course of design and construction of the Tenant Improvements, Landlord shall reimburse Tenant for TI Costs once a month against a draw request in Landlord’s standard form attached hereto as Schedule 2, containing evidence of incurrence of such TI Costs by Tenant and such certifications, lien waivers (including a conditional lien release for each progress payment and unconditional lien releases for the prior month’s progress payments), inspection reports and other matters as Landlord customarily obtains, to the extent of Landlord’s approval thereof for payment, no later than 30 days following receipt of such draw request. Upon completion of the Tenant Improvements (and prior to any final disbursement of the TI Allowance), Tenant shall deliver to Landlord: (i) sworn statements setting forth the names of all contractors and first tier subcontractors who did the work and final, unconditional lien waivers from all such contractors and first tier subcontractors (except only conditional waivers for the work covered by the final draw request); (ii) as-built plans (one copy in print format and two copies in electronic CAD format and, if prepared, copies of any 3D Building Information Models) for such Tenant Improvements; (iii) a certification of substantial completion in Form AIA G704, (iv) a certificate of occupancy for the Premises; and (v) copies of all operation and maintenance manuals and warranties affecting the Premises. Notwithstanding anything to the contrary contained herein, Tenant shall at all times have not less than a 10% retainage with respect its general contractor for the Tenant Improvements and as a condition to payment of any draw requests Landlord shall be entitled to confirm that the percentage of work completed is consistent with the percentage of payment then being sought.

     (f) Security. Provided that Tenant is not in Default under this Lease (including the Work Letter), if Landlord defaults in its obligation to disburse any portion of the TI Allowance as required under this Work Letter and Tenant expends the sum in question as permitted under this Work Letter, Tenant may offset such undisbursed amounts against Rent next coming due under this Lease.

     6. Miscellaneous.

     (a) Consents. Whenever consent or approval of either party is required under this Work Letter, that party shall not unreasonably withhold, condition or delay such consent or approval, except as may be expressly set forth herein to the contrary.

     (b) Modification. No modification, waiver or amendment of this Work Letter or of any of its conditions or provisions shall be binding upon Landlord or Tenant unless in writing signed by Landlord and Tenant.

     (c) Tenant Improvements. The construction of the Tenant Improvements shall be governed by this Work Letter and the provisions of Section 12 of the Lease shall not apply thereto.

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Work Letter — Tenant Build		249 E. Grand/Onyx — Page 6

Schedule 1

Description of Tenant Improvements

See attached schematic design drawings:

1st floor — Scope of work in bold

2nd floor — Scope of work in bold

3rd floor — Scope of work in bold

Notwithstanding anything to the contrary contained herein, Tenant acknowledges and agrees that the Tenant Improvements shall also be subject to obtaining the requisite approvals from the City of South San Francisco, any applicable architectural review boards, planning commission, city council and building department.

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Work Letter — Tenant Build		249 E. Grand/Onyx — Page 10

Schedule 2

Landlord’s Form Draw Request

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		249 E. Grand/Onyx — Page 1

EXHIBIT D TO LEASE

ACKNOWLEDGMENT OF COMMENCEMENT DATE

     This ACKNOWLEDGMENT OF COMMENCEMENT DATE is made this ___ day of                     , ___, between ARE-SAN FRANCISCO NO. 12, LLC, a Delaware limited liability company (“Landlord”), and ONYX PHARMACEUTICALS, INC., a Delaware corporation (“Tenant”), and is attached to and made a part of the Lease dated                     , 2010 (the “Lease”), by and between Landlord and Tenant. Any initially capitalized terms used but not defined herein shall have the meanings given them in the Lease.

     Landlord and Tenant hereby acknowledge and agree, for all purposes of the Lease, that the Commencement Date of the Base Term of the Lease is                     , ___, the “Rent Commencement Date is                     , ___ and the termination date of the Base Term of the Lease shall be midnight on                     , ___. In case of a conflict between the terms of the Lease and the terms of this Acknowledgment of Commencement Date, this Acknowledgment of Commencement Date shall control for all purposes.

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

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Rules and Regulations		249 E. Grand/Onyx — Page 1

EXHIBIT E TO LEASE

Rules and Regulations

     1. The sidewalk, entries, and driveways of the Project shall not be obstructed by Tenant, or any Tenant Party, or used by them for any purpose other than ingress and egress to and from the Premises.

     2. Except as provided for in Sections 42(p) through (t) of the Lease, Tenant shall not place any objects, including antennas, outdoor furniture, etc., in the parking areas, landscaped areas or other areas outside of its Premises, or on the roof of the Project.

     3. Except for animals assisting the disabled, no animals shall be allowed in the offices, halls, or corridors in the Project.

     4. Tenant shall not disturb the occupants of the Project or adjoining buildings by the use of any radio or musical instrument or by the making of loud or improper noises.

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

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

     7. Parking any type of recreational vehicles is specifically prohibited on or about the Project. Except for the overnight parking of operative vehicles, no vehicle of any type shall be stored in the parking areas at any time. In the event that a vehicle is disabled, it shall be removed within 48 hours. There shall be no “For Sale” or other advertising signs on or about any parked vehicle. All vehicles shall be parked in the designated parking areas in conformity with all signs and other markings. All parking will be open parking, and no reserved parking, numbering or lettering of individual spaces will be permitted except as specified by Landlord.

     8. Tenant shall make reasonable efforts to maintain the Premises free from rodents, insects and other pests.

     9. Landlord reserves the right to exclude or expel from the Project any person who, in the judgment of Landlord, is intoxicated or under the influence of liquor or drugs or who shall in any manner do any act in violation of the Rules and Regulations of the Project.

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

     11. Tenant shall give Landlord prompt notice of any defects in the water, lawn sprinkler, sewage, gas pipes, exterior electrical lights and fixtures, or any other service equipment affecting the Premises.

     12. Except as provided in Section 42(q) of the Lease, Tenant shall not permit storage outside the Premises, including without limitation, outside storage of trucks and other vehicles, or dumping of

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Rules and Regulations		249 E. Grand/Onyx — Page 2

waste or refuse or permit any harmful materials to be placed in any drainage system or sanitary system in or about the Premises.

     13. All moveable trash receptacles provided by the trash disposal firm for the Premises must be kept in the trash enclosure areas, if any, provided for that purpose.

     14. No auction, public or private, will be permitted on the Premises or the Project.

     15. No awnings shall be placed over the windows in the Premises except with the prior written consent of Landlord.

     16. The Premises shall not be used for lodging, sleeping or cooking (except for food preparation and service consistent with Tenant’s business and the Permitted Use) or for any immoral or illegal purposes or for any purpose other than that specified in the Lease. No gaming devices shall be operated in the Premises.

     17. Tenant shall ascertain from Landlord the maximum amount of electrical current which can safely be used in the Premises, taking into account the capacity of the electrical wiring in the Project and the Premises and the needs of other tenants, and shall not use more than such safe capacity. Landlord’s consent to the installation of electric equipment shall not relieve Tenant from the obligation not to use more electricity than such safe capacity.

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

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

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		249 E. Grand/Onyx — Page 1

EXHIBIT F TO LEASE

TENANT’S PERSONAL PROPERTY

None.

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EXHIBIT G TO LEASE

NORTHERN FACILITY LAND

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		249 E. Grand/Onyx — Page 1

EXHIBIT H TO LEASE

APPROVED SIGNAGE

Landlord acknowledges that it approves, in concept, Tenant’s proposed signage as narratively described below, subject to (a) Landlord’s review and approval of detailed specifications and/or drawings depicting the proposed manner of attachment of any exterior building signage (in order to determine the integrity, water tightness and other characteristics of the exterior walls will not be jeopardized by such attachment) and (b) applicable governmental approvals and other requirements set forth in the lease.

1. Tenant may install, up to 36” high, brushed/painted aluminum or other weather proof material, cut corporate signage and logo, mounted to the existing monument signage at the northern-most entrance to the Premises. The signage will contain the Onyx “virus” logo with the corporate name “Onyx Pharmaceuticals”. Notwithstanding the foregoing, Landlord shall remove Landlord’s own (Alexandria) signage from the existing monument and Tenant’s signage shall be required to be of a size that fits on the existing monument signage.

2. Onyx will affix signage on the west facing, top portion of the Premises. The Onyx “virus” logo and corporate name will be affixed to the fascia of the building and will be back rear-illuminated. Onyx signage will replace the existing signage from the current tenant (Exelixis).

Notwithstanding the foregoing, all of Tenant’s signage shall be required to comply with applicable Legal Requirements.

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		249 E. Grand/Onyx — Page 1

EXHIBIT I TO LEASE

INTENTIONALLY OMITTED

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		249 E. Grand/Onyx — Page 1

EXHIBIT J TO LEASE

SITE PLAN FOR PHASE I

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CONFIDENTIAL FOR ADDRESSEE ONLY
DO NOT COPY OR DISTRIBUTE

July 9, 2010

Onyx Pharmaceuticals, Inc.
2100 Powell Street
Emeryville, CA 94608
Attention: General Counsel

     Re:      249 East Grand Avenue, South San Francisco/Letter Agreement

Ladies and Gentlemen:

     Reference is made to that certain Lease of even date herewith between you, as “Tenant,” and ARE-San Francisco No. 12, LLC, a Delaware limited liability company, as “Landlord” (the “Lease”). Initially capitalized terms not specifically defined in this letter agreement are intended to have the meanings set forth for such terms in the Lease.

     This letter agreement is intended to modify the terms of Section 7 of the Lease and items 3 and 8 of Exhibit E of the Lease with respect to the meaning of “Permitted Use” under the Lease.

     This will confirm that the parties agree that the Permitted Use of the Premises may include use of a portion of the Premises as a vivarium for the housing and use in medical research of rodents and other small animals, but not primates or larger animals.

     The parties will make a commercially reasonable effort to keep the subject matter of this letter agreement confidential between them, and will not voluntarily disclose to any person the contents of this letter agreement except (a) as may be required in connection with any legal, administrative or regulatory proceeding or requirement related to the content of the Lease, and (b) to Landlord’s and Tenant’s auditors, attorneys, consultants, lenders and prospective purchasers in the ordinary course, as applicable, of Landlord’s and Tenant’s operations.

     By this letter agreement, the parties make no other change to the terms of the Lease with respect to the Permitted Use.

Onyx Pharmaceuticals, Inc.		CONFIDENTIAL FOR ADDRESSEE ONLY
July 9, 2010		DO NOT COPY OR DISTRIBUTE
Page 2 of 2

Please acknowledge your agreement to the terms of this letter agreement by countersigning below.

		Sincerely,
		ARE-SAN FRANCISCO NO. 12, LLC, a Delaware limited liability company
		By:		ALEXANDRIA REAL ESTATE EQUITIES, L.P., a Delaware limited partnership, managing member
				By:		ARE-QRS CORP.,
						a Maryland corporation, general partner

Acknowledged and agreed as of
the date first written above:

ONYX PHARMACEUTICALS, INC.,
a Delaware corporation

By:		/s/ N. Anthony Coles
Its:		CEO

By:		/s/ Matthew K. Fust
Its:		CFO