RESPIRATORY DISEASES RESEARCH COLLABORATION AND LICENSE AGREEMENT by and between Glaxo Group Limited and Five Prime Therapeutics, Inc.

“FivePrime Collaboration Know-How” shall mean any and all Know-How that (a) is Controlled by FivePrime or its Affiliates during the Term, and (b) arose from the conduct of the Research Program or FivePrime Early

Development by or on behalf of FivePrime or its Affiliates pursuant to this Agreement, but excluding any Know-How included in the FivePrime Platform Technology and FivePrime Background Know-How, and excluding FivePrime’s interest in Joint Know-How.

“GSK Licensed Product Patents” shall mean, with respect to a Committed Lead Target or its corresponding Licensed Products, any and all Patents that are Controlled by GSK or its Affiliates during the Term, that arose from the development, manufacture or commercialization of such Committed Lead Target or Licensed Products, as applicable, by or on behalf of GSK, but

excluding GSK Background Know-How and GSK Evaluation Know-How. Notwithstanding the foregoing, when the term “GSK Licensed Product Patents” is applied to GSK’s license grant to FivePrime under Section 10.6.1(d) with respect to any Terminated Product, GSK Licensed Product Patents shall include any and all Patents that are Controlled by GSK or its Affiliates as of the date such Terminated Product becomes a Terminated Product that: (a) are incorporated in such Terminated Product as of the date such Terminated Product becomes a Terminated Product, or (b) are *** for the manufacture, sale or use of such Terminated Product as of the date such Terminated Product becomes a Terminated Product.

“Know-How” shall mean any and all tangible and intangible information, data, results (including pharmacological, research and development data, reports and batch records) materials, including discoveries, improvements, compositions of matter, cell lines, assays, sequences, processes, methods, knowledge, protocols,

formulas, utility, formulations, data, inventions (whether patentable or not), strategy, know-how and trade secrets, patentable or otherwise, and all other scientific, pre-clinical, clinical, regulatory, manufacturing, marketing, financial and commercial information or data, in each case that has been treated by either Party as confidential or proprietary information and that is not generally known by the public, but excluding any of the foregoing to the extent described or claimed in any Patents.

If the Combination Product and the Licensed Product are sold separately, but the average gross selling price of the other

therapeutically active ingredient(s) cannot be determined, Net Sales of the Combination Product shall be equal to the Net Sales of the Combination Product multiplied by the fraction A/C wherein A is the average gross selling price of the Licensed Product and C is the average gross selling price of the Combination Product.

Working Group and Project Leaders.  Each Party shall establish a team (the “Project Team”) that shall work together with the other Party’s Project Team to form a single group (collectively, the “Working Group”) that is responsible for carrying out the activities under the Research Plan. Each Party may assemble its Project Team in its own discretion, based on its reasonable assessment of the staffing needs for the activities to be carried out by the respective Party. The size and composition of a Party’s Project Team may be changed by a Party at any time for any reason, in its sole discretion. GSK and FivePrime each shall appoint a member of its respective Project Team (each, a “Project Leader”), who shall be responsible for coordinating the Research Program for his/her own Project Team and the Working Group. The Project Leader(s) shall be the primary contact between the Parties with respect to the Research Program. Each Party shall notify the other within *** days of the Effective Date of the appointment of a Project Leader and shall notify the other Party in writing prior to changing this appointment. The Working Group shall make decisions on day-to-day operational matters, make decisions on which Hits shall be subject to further assays to confirm selection of such Hits as

Offered Hits, as provided in Section 3.4.1(b), and conduct the activities under the Research Plan. The Working Group shall also serve as a forum through which the Parties will share day-to-day operational information regarding the Research Program, all in accordance with the terms of this Agreement.

Scope of Joint Steering Committee Oversight.  Subject to Section 2.2.3 and except as otherwise provided herein, during the JSC Oversight Period the JSC shall oversee the Parties’ activities with respect to the Research Program as well as FivePrime Early Development of Track 2 Development for any Clinical Lead Target or Clinical Lead Product. The JSC shall perform the following functions: (a) prioritizing experiments for the Working Group; (b) resolving disputes between Project Teams comprising the Working Group; (c) conferring regarding the status of the Research Program and FivePrime Early Development; (d) reviewing data generated in the course of the Research Program and FivePrime Early Development; (e) considering and advising on any technical issues that arise in the course of the Research Program and FivePrime Early Development; (f) approving amendments to the Research Plan; (g) subject to Section 2.2.3(c) and Section 5.1.2(b), approving the FivePrime Early Development Plan and any

amendments thereto, including the selection of Proof of Mechanism Endpoints; (h) evaluate the achievement of Proof of Mechanism Endpoints for each Clinical Lead Product; (i) reviewing written updates submitted to the JSC pursuant to Section 3.5.1(c) and Section 5.2; (j) monitoring the Parties’ progress under the Research Program in accordance with the then-current Research Plan; (k) monitor FivePrime Early Development activities; and (l) performing such other obligations as set forth in this Agreement or as otherwise necessary for the conduct of the Research Program. To the extent that the Parties mutually agree that an un-performed Screening Assay(s) would not be scientifically feasible to perform, then the JSC may also, during the Research Program Term, modify the Research Plan to substitute any un-performed Screening Assay with a new Screening Assay that is of similar scope and would require similar research efforts; provided that any substitution shall not cause either GSK or FivePrime to incur additional costs, unless the Parties otherwise agree in writing. When evaluating whether a substitute Screening Assay is of similar scope and would require similar research efforts as the un-performed Screening Assay to be replaced, the JSC shall consider the specific research efforts necessary to perform both such Screening Assay and the substitute Screening Assay to ensure that the substitute Screening Assay requires equivalent research efforts. When measuring the equivalent research efforts to be transferred to a substitute Screening Assay, the JSC may also consider *** to ensure that any ***. If the JSC modifies the Research Plan to substitute a different Screening Assay as set forth herein, then each Party shall transfer such efforts as would have been expended on the un-performed Screening Assay under the Research Plan to the substitute Screening Assay. For clarity, the JSC shall not have any authority beyond the specific matters set forth in this Section 2.2.2, including not having the authority to: (i) obligate GSK to exercise the Claiming Option or Selection Option with respect to any Target, or obligate GSK to exercise its PoM Option with respect to any Clinical Lead Target; (ii) amend this Agreement (including making any modifications to the financial terms set forth herein), waive any breach of either Party under this Agreement, or terminate this Agreement; (iii) make decisions or take any actions that are inconsistent with the terms of this Agreement; (iv) approve any Research Plan amendment that would result in any increase to the payments GSK is or would be obligated to make to FivePrime pursuant to the terms of this Agreement; or (v) subject to Section 2.2.3(c), approve any Research Plan amendment that would result in the increase of any funding or resource commitment by FivePrime inconsistent with the terms of this Agreement.

Decision Making.  It is anticipated that most day-to-day decisions will be made at the level of the Working Group, except for those that are within the

purview of the JSC as specified in Section 2.2.2. If the Working Group disagrees on any of the decisions within the purview of the Working Group pursuant to Section 2.1, the Project Leaders will first try to reach agreement on such matter. If the Project Leaders are unsuccessful in reaching agreement within *** days after first attempting to resolve such matter, either Party shall have the right, upon prior written notice to the other Party, to elevate the matter to the JSC for discussion and resolution at the next regularly scheduled meeting of the JSC or at some earlier ad hoc scheduled meeting of the JSC as agreed to by the Parties. At each JSC meeting, each Party shall have collectively one (1) vote in all decisions within the JSC’s purview, as specified in Section 2.2.2, and all decisions of the JSC shall be made by unanimous vote, except as set forth below:

Decisions.  During the time period that the JPC is in place, all decisions of the JPC shall be made by consensus with each Party collectively having one (1) vote in all decisions of the committee. In the event that the JPC is unable to reach a decision within *** Business Days after it has met and attempted to reach such decision, then either Party may, by written notice to

the other, have such issue submitted to the chief patent counsels of GSK and FivePrime (“Chief Patent Counsels”), or such other person holding a similar position designated by GSK or FivePrime from time to time, for resolution. The Chief Patent Counsels shall meet promptly to discuss the matter submitted and to determine a resolution. If the Chief Patent Counsels are unable to determine a resolution in a timely manner, which shall in no case be more than *** Business Days after the matter was referred to them, then the matter will be resolved as follows: If the matter involves (i) an inventorship determination for a Collaboration Patent, or (ii) whether a Joint Patent is a Collaboration Patent, then a final decision with respect to such matter will be made by an independent patent attorney mutually acceptable to the Parties with at least *** years of experience in biotechnology-related patent prosecution (or who has such other similar credentials as mutually agreed by the Parties) within *** days of referral of the matter to the independent patent attorney, which referral will be made promptly. If the matter involves whether a Patent (other than a Joint Patent) is a Collaboration Patent, the final decision will be made by the Chief Patent Counsel of FivePrime for Patents solely Controlled by FivePrime and will be made by the Chief Patent Counsel of GSK for Patents solely controlled by GSK. Once a determination is made as provided in this Section 2.4.3 regarding whether a Joint Patent or Patent is a Collaboration Patent, final decision-making authority with respect to the filing, prosecution or maintenance of any such Collaboration Patent(s) shall be as set forth in Sections 8.2.1(c) and 8.2.1(d). For clarity, except as set forth above, patent strategy decisions regarding Patents directed to a Third Party Target, FivePrime Reserved Target, Terminated Target, Reverted Target, or Licensed Product shall be outside of the scope of the JPC.

Oversight Periods of Committees.  The activities to be performed by the JSC and the JPC shall solely relate to governance under this Agreement, and shall not involve the delivery of services. The JSC shall continue to exist until the first to occur of (a): the longer of (i) the expiration of the Research Program Term, or (ii) the completion of FivePrime’s activities under the applicable FivePrime Early Development Plan for the last Track 2 Development of a Clinical Lead Target; (b) the date the Parties mutually agree to disband the JSC; or (c) the date FivePrime provides written notice to GSK of its intention to disband and no longer participate in the JSC (such period, the “JSC Oversight Period”). The JPC shall continue to

exist until the first to occur of: (a) the expiration of the Term; (b) the date the Parties mutually agree to disband the JPC; or (c) the date FivePrime provides written notice to GSK of its intention to disband and no longer participate in the JPC. If FivePrime provides written notice of its intent to disband the JSC or JPC or the Parties mutually agree to disband such committee, such committee shall have no further obligations under this Agreement and GSK shall control any decisions that were previously the responsibility of such committee.

Research Plan.  The Parties have agreed upon a research plan, which is attached to this Agreement as Exhibit A, and which shall govern the Parties’ activities under the Research Program during the Research Program Term in Respiratory Diseases (the “Research Plan”). As more fully set forth in the Research Plan, the Parties will conduct

activities to: (a) seek to identify potential Targets in Respiratory Diseases initially through the conduct of *** Screening Assays; (b) conduct further characterization work with respect to Targets identified in Screening Assays; and (c) perform work to assess the feasibility of conducting Co-Culture Screening Assays hereunder. Subject to Section 2.2.3, each Party shall use its Commercially Reasonable Efforts to conduct those activities allocated to it under the Research Plan. Neither Party shall be obligated to conduct activities that are not described in the Research Plan, unless such additional activities are mutually agreed in writing in advance by the Parties.

FivePrime shall not use any GSK Background Know-How, GSK Background Patents, GSK Evaluation Know-How, GSK Evaluation

Patents, or any other Know-How, data or information of either Party learned by FivePrime in the conduct of the Research Program to form the basis of or to otherwise inform in any way FivePrime’s decision to in-license or otherwise acquire or access a Third Party In-Licensed Target;

If such Third Party In-Licensed Target is presented to GSK as a Hit under Section 3.4.1(a) and subsequently such Target becomes a Committed Lead Target, then promptly after such Target becomes a Committed Lead Target and to the extent FivePrime has the contractual right to do so, FivePrime shall provide to GSK a copy of the agreement(s) with Third Party(ies) under which FivePrime obtained rights to such Third Party In-Licensed Target (each, a “Third Party License Agreement”). In the event that FivePrime does not have a contractual right to provide a copy of such Third Party License Agreement to GSK, FivePrime will use its reasonable efforts under the circumstances to obtain consent from such Third Party to provide a copy of such Third Party License Agreement to GSK. GSK shall have the right, at its election, to: (i) cause FivePrime to use commercially reasonable efforts to either assign or sublicense (at GSK’s election) to GSK FivePrime’s rights and obligations under such Third Party License Agreement; or (ii) obtain the rights to such Third Party In-Licensed Target directly from such Third Party(ies), in which case FivePrime may elect to terminate such Third Party License Agreement, at no cost or expense to GSK. For the avoidance of doubt, nothing in this Section 3.3.4(d) shall be interpreted or construed as an assignment or sublicense by FivePrime to GSK of any of FivePrime’s rights or obligations, including any payment obligations, under such Third Party License Agreement unless and until GSK elects for FivePrime to assign or sublicense to GSK any such rights and obligations under such Third Party License Agreement as set forth in this Section 3.3.4(d). In the event FivePrime has obtained under such Third Party License Agreement the rights to Targets and/or technology (including any Patents and/or Know-How) in addition to such Third Party In-Licensed Target (the “Other Technology”), then: (A) FivePrime shall have the right to redact the portion of such agreement(s) pertaining solely to such Other Technology (and not to Third Party In-Licensed Target) prior to providing such agreement(s) to GSK; (B) any assignment or sublicense of FivePrime’s rights and obligations under such Third Party License Agreement to GSK shall be solely with respect to the Third Party In-Licensed Target, and the Parties shall negotiate in good faith as to a reasonable allocation of any rights or obligations, including an appropriate allocation of any costs, fees, expenses, maintenance fees, milestone payments, and royalty payments, between the

Parties as a result thereof; and (C) in the event GSK elects to obtain a direct license from such Third Party, FivePrime shall not be required to terminate such Third Party License Agreement with respect to the Other Technology. If: (A) within *** days after GSK’s receipt of the Third Party License Agreement from FivePrime, FivePrime does not receive a written notification from GSK that it elects to obtain from FivePrime an assignment or sublicense under the Third Party License Agreement; or (B) if FivePrime receives such written notification from GSK within such *** day period, but such sublicense or assignment is not effected within *** days thereafter, then FivePrime shall have the right, exercisable at its sole discretion, to terminate such Third Party License Agreement in its entirety or with respect to such Third Party In-Licensed Target.

Offered Hits. FivePrime shall offer to GSK any and all Hits from a Screening Assay that have been further confirmed, to the extent confirmation is feasible and reasonable, to exhibit in vivo activity or

Hits that, by virtue of activity in medically relevant, secondary in vitro assays, are thought to have reasonable and realistic potential as therapeutics or targets of therapeutics for Respiratory Diseases (each such Hit, an “Offered Hit”). The Working Group will determine which Hits will be subject to further assays and will determine which secondary in vitro assays or in vivo assays, using the FivePrime Platform Technology (including the *** technology), will be used, to the extent such assays are feasible and available as determined by the Working Group. In the event the Working Group determines (either at the time of its designation as a Hit or subsequently during the Research Program Term) that a Hit shall not be subject to further evaluation under the Research Program, except as set forth in Section 4.4.5(c)(i), such Hit shall become a Reverted Target, unless, within *** Business Days after such determination by the Working Group, GSK notwithstanding the Working Group’s decision decides, in its sole discretion, to designate such Hit as an Offered Hit, regardless of the amount of evaluation (if any) that has been performed on such Hit after its designation as a Hit and so notifies FivePrime in writing. At the end of the Research Program Term: (i) all Hits that have not become Reverted Targets as determined by the Working Group as set forth above or Non-Selected Targets pursuant to Section 4.4.5(c)(i) shall be deemed Offered Hits; (ii) unless otherwise agreed to by the Parties, FivePrime shall have no further obligation to conduct any activities under the Research Plan; (iii) GSK’s right to exercise its Claiming Option for any Target that, at the end of the Research Program Term, has been offered to GSK as an Offered Hit, or has been deemed an Offered Hit, in each case pursuant to this Section 3.4.1(b), shall continue after the expiration of such Research Program Term for the full Claiming Option Period of time; and (iv) GSK’s Selection Option for any Target that is a Claimed Target at the end of the Research Program Term (or becomes a Claimed Target after the end of the Research Program Term by reason of GSK’s exercise of its Claiming Option pursuant to subsection (iii) above), shall continue after the expiration of such Research Program Term for the full Selection Option Period of time.

Third Party Target List.  FivePrime shall maintain a current Third Party Target List and shall update GSK within *** days of making any changes to the Third Party Target List. FivePrime may add one or more Targets to the Third Party List from time to time, provided that such Target is

not, at the time FivePrime seeks to add it to the Third Party List, a Hit, Offered Hit, Claimed Target or a Committed Lead Target, unless such Hit, Offered Hit, Claimed Target or Committed Lead, as applicable, has become a Reverted Target or Terminated Target. In the event the right to any Third Party Target reverts to FivePrime under such Third Party collaboration so that FivePrime is no longer required to reserve such Target for such Third Party, then, such Target shall no longer be deemed a Third Party Target and if such Third Party Target qualifies as an Advanced Reserved Target at the time of reversion by the Third Party to FivePrime, then FivePrime shall have the right to add such Target to the Reserved Target List in accordance with the provisions of Section 3.4.1(d). If such Third Party Target does not qualify as an Advanced Reserved Target at the time of reversion of the Third Party Target by the Third Party to FivePrime (or if FivePrime elects not to include such Third Party Target on the Reserved Target List, notwithstanding the fact that such Third Party Target qualifies as an Advanced Reserved Target at the time of reversion), then in the event: (i) such reversion occurs during the Research Program Term, and (ii) such Target would have otherwise been designated a Hit at the time it was identified in a Screening Assay for such Respiratory Disease under the Research Program but for its inclusion on the Third Party Target List at the time, FivePrime shall inform GSK of the availability of such Target and designate such Target as a Hit, provided that GSK’s right to such Target shall be subject to any and all contractual obligations FivePrime may have to such Third Party collaborator from whom the right of such Target was reverted. Nothing herein shall be construed as preventing FivePrime from having the right to designate such reverted Third Party Target as a Reserved Target if FivePrime offers GSK such Target as a Hit as set forth in the immediately preceding sentence, and such Hit becomes a Reverted Hit as set forth in this Agreement.

The provisions regarding each Party’s rights and obligations to Targets as set forth in this Agreement shall also apply to each ***, subject to the following clarifications and further subject to Section 3.4.1(e)(ii) below: (A) if any *** (e.g.,

***) becomes a Hit, Offered Hit, Claimed Target or Committed Lead Target under this Agreement, then *** of such *** (in this example, ***) shall also be included within such corresponding designation (i.e., *** shall be deemed a *** Hit, Offered Hit, Claimed Target or Committed Lead Target, as the case may be), without counting any such *** or *** thereof as *** Targets, without exercising a separate Claiming Option or Selection Option (or paying a separate Claiming Fee or Selection Fee) for *** and ***, and without counting *** and ***, in each case to the extent included on the Reserved Target List, as *** Targets (as applicable); (B) if any *** (e.g., *** is a Reserved Target, then *** of such *** (in this example, ***) shall also be deemed, collectively with the ***, a Reserved Target, without counting any such *** as *** Reserved Targets; (C) if any *** (e.g., ***) is a Third Party Target, then *** of such *** (in this example, ***) shall also be deemed, ***, a Third Party Target, without counting any such *** as *** Third Party Targets; and (D) a *** shall be deemed a Reserved Target or Third Party Target if such ***, or any of the *** (in this example, ***), is a Reserved Target or Third Party Target (including by operation of subsection (B) above).

In the event that any *** (whether or not *** is a Reserved Target and whether or not *** has been deemed to be an Advanced Research Target as provided in Section 3.4.1(d)(i)(6)(aa)) is also a *** of two (2) or more other *** (such *** is referred to as a “***”), then each Party’s rights to such *** under Sections 3.4.1(e)(i)(A) and (B) above shall be non-exclusive as between the Parties. The determination of whether a *** is a *** shall be made based on existing data in the possession of either Party or in the existing literature. For the purposes of example only, if *** is a Reserved Target and the *** is a ***, then: (A) *** shall *** be deemed *** Reserved Target; (B) FivePrime shall have the right to research, develop or commercialize Biologics and Compounds to *** as if it were a Reserved Target; (C) in the event such *** (i.e., ***), or a *** comprising such *** (i.e., ***), qualifies as a Hit in a Screening Assay conducted under the Research Program, such *** shall not be excluded as a Hit by reason of the existence of *** on the Reserved Target List; and (D) GSK’s license under Section 4.1.1 and Section 4.1.2 with respect to

such *** (i.e., ***) (either as a Target by itself or as *** (i.e., ***)) shall be non-exclusive. Similarly, if *** is not a Reserved Target, but is a Hit, and *** is a ***, then: (A) *** shall *** be deemed *** Offered Hit, Claimed Target or Committed Lead Target, as applicable; (B) the licenses granted to GSK under Section 4.1.1 and Section 4.1.2 with respect to such *** shall be exclusive and GSK shall have the exclusive right to research, develop and commercialize Biologics and Compounds to such ***; and (C) the licenses granted to GSK under Section 4.1.1 and Section 4.1.2 shall be non-exclusive with respect to such *** (either by itself or as *** of another *** (i.e., ***).

During the period commencing on the date on which FivePrime has delivered all Offered Hit Data with respect to an Offered Hit and continuing for *** days thereafter (the “Claiming Option Period”), GSK shall have an exclusive option (even as to FivePrime) to select or decline such Offered Hit for evaluation and further development (each such option, a “Claiming Option”). GSK may alternatively elect to exercise its Claiming Option with respect to a GSK Alternative Target in lieu of such Offered Hit. GSK shall have the right, but not the obligation, to exercise its Claiming Option prior to the expiration of the Claiming

Option Period by providing written notice to FivePrime. Upon FivePrime’s receipt of such written notice from GSK that it is exercising its Claiming Option for such Offered Hit or GSK Alternative Target, such Offered Hit or GSK Alternative Target shall be deemed to be and designated as a Claimed Target or GSK Alternative Target, as applicable, under this Agreement. Notwithstanding the foregoing and subject to Section 3.4.1(d), GSK shall not have the right to exercise its Claiming Option with respect to any GSK Alternative Target if such GSK Alternative Target is a Reserved Target or Third Party Target. GSK shall, in the event it exercises the Claiming Option with respect to such Offered Hit or GSK Alternative Target, pay FivePrime the Claiming Fee as set forth in Section 6.3.1. If (A) prior to the expiration of the Claiming Option Period, GSK notifies FivePrime that it is not exercising its Claiming Option with respect to a particular Offered Hit or any GSK Alternative Target in lieu of such Offered Hit, or (B) GSK does not exercise its Claiming Option with respect to a particular Offered Hit or any GSK Alternative Target in lieu of such Offered Hit by providing FivePrime with written notification prior to the expiration of the Claiming Option Period, then in each case of (A) and (B), such Offered Hit shall cease to be an Offered Hit and such Offered Hit shall become a Reverted Target. If during the Claiming Option Period for a particular Offered Hit GSK elects to exercise its Claiming Option with respect to a GSK Alternative Target in lieu of such Offered Hit, such Offered Hit shall not become a Reverted Target, but shall instead remain subject to GSK’s exclusive option until such time as GSK either exercises or declines its Selection Option with respect to such GSK Alternative Target. If GSK exercises its Selection Option with respect to such GSK Alternative Target, such Offered Hit shall be included in the licenses granted to GSK in accordance with Section 4.1. If GSK declines to exercise its Selection Option with respect to such GSK Alternative Target, such Offered Hit shall, at the expiration of the relevant Selection Option Period, be deemed a Reverted Target. If an Offered Hit becomes a Claimed Target in accordance with this Section 3.4.2(b)(i) but later GSK fails to pay FivePrime any Claiming Fee due with respect to such Claimed Target in accordance with Section 6.3.1, then such Claimed Target shall thereupon cease to be a Claimed

Target and shall be deemed to be a Reverted Target effective retroactively as of the date of GSK’s exercise of the Claiming Option with respect to such Claimed Target. The collection, collectively at any given time, of all Claimed Targets from a particular Screening Assay and GSK Alternative Targets selected with respect thereto, shall be deemed the “Claimed Targets Basket” for such Screening Assay.

During the Selection Option Period (as defined in Section 3.4.4(b)) for each Claimed Target, GSK shall have an exclusive option (even as to FivePrime) with respect to each such Claimed Target, exercisable as set forth below, to select such Claimed Target (or, if GSK elected to select a GSK Alternative Target in lieu of an Offered Hit as set forth in Section 3.4.2(b)(i), then such GSK Alternative Target) for the purpose of developing, using, manufacturing and commercializing any product comprising a Biologic and/or Compound that is directed to or against (or, in the case of a Claimed Target that is a *** Target, in the ***), or incorporates or is derived from, such Claimed Target or GSK Alternative Target, as applicable (each such option, the “Selection Option”). GSK shall have the right, but not the obligation, prior to the expiration of the Selection Option Period, to exercise the Selection Option by providing FivePrime with written notice. Upon FivePrime’s receipt of such written notice from GSK that it is exercising its Selection Option with respect to a particular Claimed

Target or GSK Alternative Target, such Claimed Target or GSK Alternative Target shall be deemed to be and designated as a Committed Lead Target or GSK Alternative Committed Lead Target, as applicable. In the event GSK exercises its Selection Option with respect to a particular Claimed Target or GSK Alternative Target as provided herein, GSK shall pay FivePrime the Selection Fee as set forth in Section 6.3.2.

If (A) prior to the expiration of the applicable Selection Option Period, GSK notifies FivePrime that GSK will not exercise its Selection Option with respect to a particular Claimed Target or any GSK Alternative Target in lieu of such Claimed Target, or (B) prior to the expiration of the applicable Selection Option Period, FivePrime has not received from GSK such notification of its exercise of the Selection Option with respect to a particular Claimed Target or any GSK Alternative Target in lieu of such Claimed Target, then in either case of (A) or (B), such Claimed Target shall cease to be a Claimed Target and such Claimed Target shall become a Reverted Target. If during the Selection Option Period for a particular Claimed Target GSK elects to exercise its Selection Option with respect to a GSK Alternative Target in lieu of such Claimed Target, such Claimed Target shall not become a Reverted Target, but shall instead remain subject to GSK’s exclusive licenses as set forth in Section 4.1. If GSK exercises its Selection Option with respect to such GSK Alternative Target, such Claimed Target shall be included in the licenses granted to GSK in accordance with Section 4.1. If GSK declines to exercise its Selection Option with respect to such GSK Alternative Target, such Claimed Target shall, at the expiration of the relevant Selection Option Period, be deemed a Reverted Target. If GSK exercises its Selection Option with respect to a GSK Alternative Committed Lead Target rather than a Committed Lead Target, then: (A) development of such GSK

Alternative Committed Lead Target in compliance with Section 5.2.2 shall satisfy GSK’s diligence obligations in Section 5.2.2 with respect to such Committed Lead Target; (B) GSK shall pay to FivePrime, upon the achievement of each relevant milestone or Net Sales with respect to the GSK Alternative Committed Lead Target, the applicable milestone payment and/or royalty due with respect to a Compound Target, as if such milestone or Net Sales had been achieved with respect to the associated Committed Lead Target; (C) the Committed Lead Target for which the GSK Alternative Committed Lead Target was substituted shall remain subject to GSK’s exclusive licenses granted herein and will not become a Reverted Target unless and until the GSK Alternative Committed Lead Target is terminated by GSK. If a Claimed Target becomes a Committed Lead Target in accordance with Section 3.4.4(a) but later GSK fails to pay FivePrime the Selection Fee due with respect to such Committed Lead Target as set forth in Section 6.3.2, then such Committed Lead Target shall thereupon cease to be a Committed Lead Target and shall be deemed a Reverted Target effective retroactively as of the date that GSK exercises its Selection Option with respect to such Committed Lead Target. If a GSK Alternative Target becomes a GSK Alternative Committed Lead Target in accordance with Section 3.4.4(a) but later GSK fails to pay FivePrime the Selection Fee due with respect to such GSK Alternative Committed Lead Target, as set forth in Section 6.3.2, then such GSK Alternative Committed Lead Target shall not become a Reverted Target, but shall instead be subject to the terms of Section 10.6.1(c).

GSK Alternative Targets; GSK Alternative Committed Lead Targets.  Notwithstanding Section 3.4.2(b)(ii), GSK shall have the right, in its discretion, to select a Claimed Target as a Committed Lead Target for development as a Compound Target or a Biologics

Target, as designated by GSK, and subject to payment of the applicable Selection Fee for a Compound Target in accordance with Section 3.4.4(a), to substitute such Committed Lead Target with a GSK Alternative Committed Lead Target. Notwithstanding the foregoing and subject to Section 3.4.1(d), GSK shall not have the right to substitute a Committed Lead Target with a GSK Alternative Target, if such GSK Alternative Target is a Reserved Target or Third Party Target. If GSK elects to substitute a GSK Alternative Committed Lead Target for a Committed Lead Target and to develop a GSK Alternative Committed Lead Target as a Compound Target in lieu of developing the substituted Committed Lead Target, then: (A) development of such GSK Alternative Committed Lead Target in compliance with Section 5.2.2 shall satisfy GSK’s diligence obligations in Section 5.2.2 with respect to such Committed Lead Target; (B) GSK shall pay to FivePrime, upon the achievement of each relevant milestone or Net Sales with respect to the GSK Alternative Committed Lead Target, the applicable milestone payment and/or royalty due with respect to a Compound Target, as if such milestone or Net Sales had been achieved with respect to the associated Committed Lead Target; (C) the Committed Lead Target for which the GSK Alternative Committed Lead Target was substituted shall remain subject to GSK’s exclusive licenses granted herein and will not become a Reverted Target unless and until the GSK Alternative Committed Lead Target is terminated by GSK. In the event that GSK has paid a Selection Fee for the Committed Lead Target prior to substituting such Committed Lead Target with a GSK Alternative Committed Lead Target, GSK shall not have an obligation to pay a Selection Fee or to pay any other fee in connection with the substitution of the GSK Alternative Committed Lead Target for the Committed Lead Target.

HSR Clearance.  If GSK reasonably determines in good faith prior to the expiration of the applicable Selection Option Period for a particular Claimed Target that the exercise of Selection Option with respect to such Claimed Target is required to be filed with the United States Department of Justice (the “DOJ”) or the United States Federal Trade Commission (the “FTC”), as applicable, under the ▇▇▇▇-▇▇▇▇▇-▇▇▇▇▇▇ Antitrust Improvements Act of 1976, as amended (15 U.S.C. §18a) (“HSR”) or with equivalent foreign governmental authorities under any similar foreign law, GSK shall provide written notice of its desire to exercise such Selection Option and of the perceived HSR filing requirement to FivePrime prior to the expiration of the applicable Selection Option Period, and the applicable

Selection Option Period shall be automatically extended for *** days. GSK will be obligated to submit any such filings that are required, as promptly as practicable but, in any event, within *** Business Days of FivePrime’s receipt of this written notice of a GSK perceived need to file. GSK shall provide FivePrime with a copy of the portion of GSK’s initial filing pertaining to FivePrime’s technology for FivePrime’s comment prior to its filing. In addition, GSK shall update FivePrime with any response from the FTC promptly after GSK receives such response, and shall provide FivePrime with a copy of the portion of the proposed response thereto pertaining to FivePrime’s technology for FivePrime’s comment. If the HSR or other clearance is not granted prior to the expiration of the Selection Option Period (as extended herein), or if GSK receives a “Second Request” from the DOJ or FTC or receives a similar request for additional information or materials from another governmental authority in connection with such filing, the once extended Selection Option Period shall be extended again for such additional period of time as reasonably necessary (which additional period of time is not expected to exceed an additional *** days unless reasonably required to obtain clearance) to permit the Parties to obtain HSR or other governmental clearances and to respond to requests to provide additional information or materials to the governmental authority (or authorities). If HSR or other governmental clearance has not been granted by the expiration of the Selection Option Period (as extended herein), FivePrime and GSK shall promptly meet to discuss in good faith whether an additional extension of the Selection Option Period is reasonable under the circumstances. Notwithstanding the foregoing, nothing in this Section shall require either Party to divest any assets in such Party’s ownership or Control as of the Effective Date or during the Term. GSK shall be solely responsible for all reasonable costs and expenses of either Party in connection with the grant of any exclusive license to GSK hereunder (including all governmental filing or other fees, and any other costs and expenses) arising from pursuing or obtaining any HSR or other governmental approval addressed in this Section 3.4.5.

Sharing of Data.  Subject to the specific limitations in Section 3.4, the Parties shall share the results of all research performed by or on behalf of either Party under the Research Plan or by GSK on Claimed Targets prior to

the time when GSK exercises its Selection Option with respect to such Claimed Target or when such Claimed Target becomes a Reverted Target, as the case may be, provided that nothing in this Agreement, including in this Article 3, shall be interpreted as obligating FivePrime to disclose to GSK: (a) any data obtained by FivePrime in testing any Target in any Third Party Assay; or (b) the specific identity of any Target that is a Reserved Target or a Third Party Target.

MATERIALS SUPPLIED BY THE MATERIALS TRANSFERRING PARTY PURSUANT TO THIS SECTION 3.5.7 ARE SUPPLIED IN “AS IS” CONDITION WITH NO WARRANTY, EXPRESS, IMPLIED OR STATUTORY, INCLUDING WARRANTIES OF MERCHANTABILITY, TITLE, NON-INFRINGEMENT, EXCLUSIVITY, OR FITNESS FOR A PARTICULAR PURPOSE. THE MATERIALS RECEIVING PARTY SHALL NOT AND

SHALL NOT PERMIT ANY PERSON TO ADMINISTER ANY SUCH MATERIALS TO HUMANS UNDER ANY CIRCUMSTANCES. ANY MATERIAL DELIVERED PURSUANT TO THIS AGREEMENT IS UNDERSTOOD TO BE EXPERIMENTAL IN NATURE AND MAY HAVE HAZARDOUS PROPERTIES. THE MATERIALS RECEIVING PARTY WILL HANDLE THE MATERIAL ACCORDINGLY AND WILL INFORM THE MATERIALS TRANSFERRING PARTY IN WRITING OF ANY ADVERSE EFFECTS EXPERIENCED BY PERSONS HANDLING THE MATERIAL. THE RECEIVING PARTY ASSUMES ALL LIABILITY FOR DAMAGES WHICH MAY ARISE FROM ITS USE, STORAGE OR DISPOSAL OF THE MATERIAL.

The Materials Receiving Party assumes all liability for damages which may arise from its use, storage or disposal of the Materials. The Materials Transferring Party shall not be liable to the Materials

Receiving Party for any loss, claim or demand made by the Materials Receiving Party, or made against the Materials Receiving Party by any Third Party, due to or arising from the use of the Materials, except to the extent permitted by applicable law, when caused by the gross negligence or wilful misconduct of the Materials Transferring Party.

In the event: (i) the Parties desire to use any Human Biological Samples obtained by either Party prior to the Effective Date; and (ii) the Party that obtained such Human Biological Sample discovers that the terms and conditions under which such Human Biological Sample was obtained do not meet the requirements of Section 3.5.12(b), then, prior to using such Human Biological Sample in the Research Program, the Party who has obtained such Human Biological Sample shall disclose to the other Party the terms and conditions under which such Human Biological Sample was obtained, and the Parties shall discuss in good faith and in an expeditious manner the suitability of using such Human Biological

Sample in the Research Program, including whether additional consents should be obtained. The Parties shall not use such Human Biological Sample in the Research Program unless both Parties agree to such use. If the Parties agree to use such Human Biological Sample in the Research Program, such use shall not be deemed to constitute a breach of any representation or warranty in this Section 3.5.12.

Development and Commercialization Licenses.  Subject to the terms and conditions of this Agreement, commencing upon the designation of a

Claimed Target as a Committed Lead Target pursuant to Section 3.4.4, or the designation of a GSK Alternative Committed Lead Target pursuant to Section 3.4.4 , as applicable, FivePrime hereby grants to GSK an exclusive, royalty-bearing license (as set forth in Article 6), with the right to grant sublicenses (including the right to further sublicense) pursuant to Section 4.1.3, under the FivePrime Collaboration Patents, FivePrime Collaboration Know-How, and FivePrime’s interest in the Joint Patents and Joint Know-How, to make, have made, use, sell, offer for sale and import Licensed Product(s) (for any *** Target, solely in ***) with respect to such Committed Lead Target and such GSK Alternative Committed Lead Target, as applicable, in the Field in the Territory, and a non-exclusive, royalty-free license, with the right to grant sublicenses (including the right to further sublicense) pursuant to Section 4.1.3, under the FivePrime Background Know-How and FivePrime Background Patents, solely to the extent necessary to exercise the exclusive license granted in this Section 4.1.2 to GSK. The license granted in this Section 4.1.2 shall not be construed as granting GSK the right under any FivePrime Background Know-How, FivePrime Background Patents, FivePrime Collaboration Patents, or FivePrime Collaboration Know-How, to research, develop, make, use or commercialize a Licensed Product that is directed to, derived from, or incorporates a Target other than a Committed Lead Target or a GSK Alternative Committed Lead Target, as applicable.

Research License; Track 2 Development License.  Subject to the terms and conditions of this Agreement, effective only during the Research Program Term and, if applicable, during the Clinical Lead Target Development Period solely with respect to Track 2 Development activities conducted by FivePrime with respect a Clinical Lead Target, GSK hereby grants to FivePrime a fully-paid, royalty-free, non-exclusive license: (i) under GSK Background Patents, GSK Background Know-How, GSK Evaluation Patents and GSK Evaluation Know-How, solely to the extent necessary for FivePrime to conduct the obligations and responsibilities allocated

to FivePrime under the Research Plan; and (ii) under GSK Background Patents, GSK Background Know-How, GSK Evaluation Patents, and GSK Evaluation Know-How, solely to the extent necessary for FivePrime to conduct the obligations and responsibilities allocated to FivePrime under each FivePrime Early Development Plan for the Track 2 Development of a Clinical Lead Target. In addition, GSK hereby grants to FivePrime a fully-paid, non-exclusive, royalty-free sublicense under GSK’s exclusive license to the FivePrime Collaboration Patents, FivePrime Collaboration Know-How, and FivePrime’s interest in the Joint Patents and Joint Know-How, solely during the Clinical Lead Target Development Period and solely for use by FivePrime in the conduct of obligations and responsibilities allocated to FivePrime under each FivePrime Early Development Plan for the Track 2 Development of a Clinical Lead Target and Clinical Lead Products with respect thereto. Subject to Section 5.5, FivePrime may grant sublicenses (with the right to grant further sublicenses) under the foregoing license solely to its Affiliates and Contractors solely to conduct such obligations and responsibilities on its behalf.

GSK hereby covenants that it shall not use any FivePrime Background Know-How, FivePrime Background Patents, FivePrime Collaboration Know-How or FivePrime Collaboration Patents for any purposes other than those expressly permitted in Section 4.1, Section 3.4.1(c), Section 3.4.2,

Section 3.4.3, or as otherwise expressly permitted in this Agreement, and GSK specifically covenants that it shall not use any FivePrime Background Know-How, FivePrime Background Patents, FivePrime Collaboration Know-How, or FivePrime Collaboration Patents to design or conduct screening assays, or to identify additional Targets, outside of the Research Program.

as long as GSK continues to have rights to develop or commercialize any Committed Lead Target, GSK Alternative Committed Lead

Target, or Licensed Products derived from such Committed Lead Target or GSK Alternative Committed Lead Target and for as long as the following information remains non-public and proprietary, disclose to any Third Party, which of the Claimed Targets have been selected by GSK as Committed Lead Targets, which GSK Alternative Targets have been selected by GSK as GSK Alternative Committed Lead Targets, or the behavior of any Committed Lead Target or GSK Alternative Committed Lead Target in other screening assays without redacting the identity of such Committed Lead Target or GSK Alternative Committed Lead Target, as applicable, in each case without GSK’s prior written consent.

GSK Exclusivity.  Subject to Section 4.4.5(c), ***, GSK shall not, and shall cause its Affiliates not to, (alone or with or for a Third Party) conduct any Screening Assays, and shall not offer or grant rights to any Third Party under which

such Third Party would conduct any Screening Assays to discover or identify Targets in order to develop pharmaceuticals or therapeutics to *** other than as set forth herein. For the avoidance of doubt and subject to Section 4.4.5(c), nothing herein shall be construed to prohibit GSK or its Affiliates from pursuing, or continuing to pursue any other internal GSK programs or Third Party programs for ***, or from screening GSK’s internal libraries for Targets. This Section 4.4.5(a)(ii) shall not be construed as prohibiting GSK from using any commercially available screening assays or any screening assays disclosed in the scientific literature, provided that GSK shall not use any FivePrime Background Know-How, FivePrime Background Patents, FivePrime Collaboration Know-How or FivePrime Collaboration Patents in connection therewith.

Non-Selected Targets.  In the event that FivePrime presents a Target as a Hit to GSK that, at the time such Hit was presented to GSK, GSK either: (a) was conducting research, development or commercialization activities with respect to such Target on its own as part of an internal program or as part of a program in collaboration with a Third Party in Respiratory Diseases, or (b) had actual knowledge that such Target is a therapeutic target or potential therapeutic agent for Respiratory Diseases, in each of (a) and (b) above as evidenced by GSK’s written records (the “Non-Selected Target Criteria”), then GSK shall inform FivePrime within *** Business Days after such Hit has been presented to GSK that such Hit meets the Non-Selected Target Criteria as set forth in this Section 4.4.5(c)(i). Notwithstanding the foregoing, GSK may nevertheless elect to exercise its Claiming Option with respect to such Hit as if it were an Offered Hit. If, however, GSK elects not to exercise its Claiming Option with respect to such Hit, then such Hit shall not be deemed a Reverted Target as that term is defined herein but rather shall thereafter be referred to as a

“Non-Selected Target” and such Non-Selected Target shall be considered outside of the scope of this Agreement and the Research Program with respect to Respiratory Diseases. For clarity, subject to the restrictions set forth in Sections 4.4.5(a) and (b), each Party may research, develop, validate, commercialize, or undertake any other activities in their sole discretion with respect to such Non-Selected Target without any further obligations, including payment obligations, of any kind to the other Party.

Designation of Clinical Lead Targets; Substitution Rights. Prior to GSK paying the Selection Fee with respect to a Committed Lead Target included within a Claimed Targets Basket, the Parties will discuss and agree upon the number and specific Committed Lead Targets from such Claimed Targets Basket that each Party may select to develop as Committed Lead Targets under Track 1

Development or Clinical Lead Targets under Track 2 Development, as applicable, considering each Party’s available resources and capabilities at the time to conduct the activities necessary for such Track 1 Development or Track 2 Development, as applicable, but subject to each Party’s right to alternate in such selection as set forth in this Section 5.1.2(a); provided, however, that all GSK Alternative Committed Lead Targets will be developed by GSK under Track 1 Development. With respect to each Claimed Targets Basket, GSK shall have the right to select the first Committed Lead Target or GSK Alternative Committed Lead Target in such Claimed Targets Basket for research and development pursuant to Section 5.1.1 (such development, “Track 1 Development”) and FivePrime shall have the right to select the second Committed Lead Target in such Claimed Targets Basket for further research, preclinical and clinical development (such development, “Track 2 Development” and such Committed Lead Target a “Clinical Lead Target”), in each case in accordance with the agreed-upon number and specific Committed Lead Targets as agreed by the Parties in advance as set forth above. The Parties’ selection rights shall continue to alternate with respect to Committed Lead Targets in such Claimed Targets Basket until all such Committed Lead Targets have been selected. If GSK selects at least *** Committed Lead Target and pays the relevant Selection Fee, but thereafter elects not to exercise its right to select such Committed Lead Target (or the first of such Committed Lead Targets, as applicable) for Track 1 Development, GSK shall offer FivePrime the right to select such Committed Lead Target for Track 2 Development. If FivePrime elects to pursue Track 2 Development with respect to such Committed Lead Target, then FivePrime shall use its Commercially Reasonable Efforts, consistent with the terms of this Agreement, to develop such Committed Lead Target through to achievement of the Proof of Mechanism Endpoints as mutually agreed by the Parties in advance. If FivePrime does not exercise its right to pursue Track 2 Development with respect to such Committed Lead Target, then such Committed Lead Target shall be a Reverted Target subject to Section 4.4.5(c)(ii).

If during Track 1 Development of a Committed Lead Target, GSK determines that a different Committed Lead Target or GSK Alternative Committed Lead Target may have a more suitable development profile, GSK may elect to substitute such Committed Lead Target under development (a “Track 1 Substitution”) with such alternative Committed Lead

Target or GSK Alternative Committed Lead Target (a “Substituted Lead Target”) so long as (1) the Committed Lead Target being replaced was selected within the prior *** as a Committed Lead Target for Track 1 Development by GSK, and (2) FivePrime has not selected the Substituted Lead Target designated by GSK for Track 2 Development as a Clinical Lead Target. If GSK elects to make such a substitution, GSK will pay the Selection Fee for the Substituted Lead Target, if owed, and shall have a right to offset such Selection Fee against future milestone payments owed by GSK. GSK may, in GSK’s discretion, elect to first offset such Selection Fee against any future milestone payment(s) to be made by GSK to FivePrime for the First Initiation of a GLP toxicology study for any Licensed Product with respect to such Substituted Lead Target and thereafter against any additional future milestones owed by GSK until such Selection Fee amount has been exhausted. The Committed Lead Target replaced by the Substituted Lead Target shall revert to FivePrime and become a Reverted Target subject to Section 4.4.5(a)(ii). GSK shall have the right to make no more than two (2) Track 1 Substitutions.

If during Track 2 Development of a Clinical Lead Target, FivePrime determines that a different Committed Lead Target may have a more suitable development profile, FivePrime will notify GSK and the Parties will discuss whether the alternative Committed Lead Target should be substituted for such original Clinical Lead Target. GSK shall have the right to conduct intellectual property due diligence with respect to such proposed alternative Committed Lead Target and with respect to the proposed activities to be conducted under FivePrime’s proposed FivePrime Early Development Plan for such Committed Lead Target, provided that FivePrime shall not be required to continue to carry on Track 2 Development of the original Clinical Lead Target during the period of time during which GSK is conducting intellectual property due diligence with respect to the proposed alternative Committed Lead Target. If, however, GSK does not consent to the proposed alternative Committed Lead Target, FivePrime shall promptly resume activities with respect to the original Clinical Lead Target, provided that FivePrime shall have the

right to discontinue the activities with respect to such original Clinical Lead Target for reasons such as safety, toxicity, efficacy, clinical trial enrollment, action of Regulatory Authority or intellectual property matters. Subject to the conclusion of intellectual property due diligence to GSK’s satisfaction and GSK’s approval of the proposed FivePrime Early Development Plan for such proposed alternative Committed Lead Target, FivePrime may select such proposed alternative Committed Lead Target for Track 2 Development (a “Track 2 Substitution”), so long as (1) the Clinical Lead Target being replaced was selected within the prior *** as a Clinical Lead Target for Track 2 Development by FivePrime, and (2) GSK has not selected the subsequent Committed Lead Target for Track 1 Development. Upon such substitution, the Clinical Lead Target being replaced shall no longer be deemed a Clinical Lead Target and shall thereafter be a Committed Lead Target and GSK shall have the right to elect to pursue Track 1 Development of such Committed Lead Target. If GSK elects to pursue Track 1 Development of such Committed Lead Target, GSK shall have the right to credit an amount equal to the incremental milestone payments made by GSK to FivePrime by reason of such Target being a Clinical Lead Target rather than a Committed Lead Target on Track 1 Development against any future milestone payments owed by GSK to FivePrime with respect to the development and commercialization of such Target by GSK. If GSK does not elect to further develop and commercialize such Committed Lead Target within *** days after the date such FivePrime shall have replaced such Committed Lead Target was replaced by FivePrime, then FivePrime shall refund GSK the Selection Fee with respect to such Committed Lead Target, and such Committed Lead Target shall revert to FivePrime and become a Reverted Target, subject to Section 4.4.5(c)(ii).

FivePrime Early Development Plan; Proof of Mechanism Endpoints.  For each Clinical Lead Target, FivePrime shall have the right to (i) develop Biologics directed to or against, or that incorporate or are directly derived from, such Clinical Lead Target (each, a “Clinical Lead Product”) and (ii) advance a Clinical Lead Product through to a measurable clinical proof of mechanism endpoint(s) to be tested in a Phase 1 Clinical Trial or a Phase 2

Clinical Trial, or both (such proof of mechanism endpoints, “Proof of Mechanism Endpoints”) to be agreed upon by the Parties in advance, subject to ***. Prior to initiating FivePrime Early Development with respect to a particular Clinical Lead Target, FivePrime shall propose a clinical development plan for review and approval by GSK (which may be in the form of approval by GSK’s Technology Investment Board) and the JSC (the “FivePrime Early Development Plan”), which shall include details of the discovery technology FivePrime will use to make Clinical Lead Products to such Clinical Lead Target, the selection criteria that FivePrime will use to select a Clinical Lead Product before conducting a toxicology study conducted pursuant to good laboratory practices (GLP) for the purpose of submitting an IND for such Clinical Lead Product, proposed Proof of Mechanism Endpoints for such Clinical Lead Product, and any necessary manufacturing plans for the manufacture of clinical supply of any such Clinical Lead Product (as set forth in Section 5.5) for use in connection with the FivePrime Early Development Plan. GSK shall have the right to undertake intellectual property due diligence both with respect to each Clinical Lead Target and with respect to the pre-clinical and clinical activities proposed to be conducted under FivePrime’s proposed FivePrime Early Development Plan for such Clinical Lead Target (including any technology platforms proposed by FivePrime for use in connection with such activities) and a right to undertake appropriate due diligence with respect to any proposed manufacturing activities for the manufacture of clinical supplies of a Clinical Lead Target, in each case prior to the JSC’s approval of a FivePrime Early Development Plan for such Clinical Lead Target. FivePrime shall use commercially reasonable efforts, including entering into any necessary three-way confidentiality agreements with GSK and any applicable Third Parties, to assist and facilitate GSK in undertaking such intellectual property and manufacturing due diligence. FivePrime shall not present the FivePrime Early Development Plan to the JSC unless and until GSK has completed such intellectual property due diligence and manufacturing due diligence to GSK’s satisfaction and such FivePrime Early Development Plan has been approved by GSK. FivePrime shall propose the Proof of Mechanism Endpoints in the draft FivePrime Early Development Plan and the JSC shall approve or modify, subject to ***, such Proof of Mechanism Endpoints. Such Proof of Mechanism Endpoints may consist of a determination of pharmacodynamic effect, a biomarker measurement, or a functional effect, or any combination of such metrics or other metrics. If the

JSC cannot agree on the Proof of Mechanism Endpoints, the matter shall be escalated to *** and ***, or their respective designees with the power and authority to resolve such matter. If the Parties still cannot agree on a matter after such escalation, then ***, provided that any such Proof of Mechanism Endpoint selected by *** shall be an endpoint that has proven to be measurable and is relevant to the indication of interest, unless both Parties agree otherwise.

Promptly after the final data lock of the clinical trial database of a Clinical Trial in which Proof of Mechanism Endpoints were tested by FivePrime in Track 2 Development, FivePrime shall provide to GSK and the JSC the final and complete data package from the final data lock from such Proof of Mechanism Clinical Trial, including all preclinical data and results regarding such Clinical Lead Product as well as all available data and results from any Clinical Trials of such Clinical Lead Product (“PoM Option Data Package”) together with the complete CMC Work Package. FivePrime shall certify in writing to GSK the date upon which FivePrime has delivered the final and complete PoM Data Package and CMC Work Package to GSK. GSK shall have the right to exercise its exclusive option to obtain an exclusive license from FivePrime to make, have made, use, sell, offer for sale and import Licensed Products with respect to the Clinical Lead Target for such Clinical Lead Product, including the right to any Clinical Lead Product developed by FivePrime in the course of such FivePrime Early Development (the “PoM Option”), by providing FivePrime written notification of such option exercise at any time up to *** days after GSK’s receipt of such PoM Option Data Package and CMC Work Package and FivePrime’s written certification with respect to the completeness thereof (the “PoM Option Exercise Period”). On or after FivePrime’s receipt of GSK’s PoM Option exercise notice, FivePrime shall Invoice GSK and GSK shall pay to FivePrime within *** days after receipt of an Invoice from FivePrime therefor, the PoM Option exercise fee of (A) *** dollars ($***), if GSK exercises its PoM Option prior to the Initiation of a Phase 2 Clinical Trial of a Clinical Lead Product for such Clinical Lead Target; or (B) *** dollars ($***), if GSK exercises its PoM Option upon or after the

Initiation of a Phase 2 Clinical Trial of a Clinical Lead Product for such Clinical Lead Target, with such PoM Option exercise becoming effective after FivePrime’s receipt of such notification and payment. If GSK does not exercise its PoM Option with respect to a Clinical Lead Target within the PoM Option Exercise Period, then such Clinical Lead Target shall cease to be a Clinical Lead Target (or a Committed Lead Target) and shall become a Reverted Target subject to Section 4.4.5(c)(ii).

FivePrime shall, during the Clinical Lead Target Development Period for a particular Clinical Lead Target and at its sole cost and expense, use

Commercially Reasonable Efforts to design and develop at least one (1) Clinical Lead Product and conduct further lead optimization on such Clinical Lead Product, such as performing humanization of mouse monoclonal antibodies and protein or antibody engineering as appropriate. Within *** days after the end of each Calendar Quarter, FivePrime shall provide GSK with a written report summarizing its development activities with respect to each Clinical Lead Target and its related Clinical Lead Product(s) in such Calendar Quarter.

GSK shall be solely responsible, at its sole cost and expense, for the manufacturing of Licensed Products for development and commercialization under this Agreement, except that FivePrime shall be responsible, at its sole cost and expense, for the manufacturing of clinical supply of Licensed Products with respect to any Clinical Lead Target during the Clinical Lead Target Development Period. FivePrime shall prepare and provide to GSK a complete proposed work package including the activities to be undertaken by FivePrime or by an approved Manufacturing Contractor (as set forth in this Section 5.5) on behalf of FivePrime, in connection with the scale up and manufacture of clinical supply of Licensed Products with respect to Clinical Lead Targets. GSK and FivePrime will discuss such proposed manufacturing work package (the “CMC Work Package”) and will agree upon the scope and content thereof, subject to ***. FivePrime shall have the right to select a third party contract manufacturing organization to conduct such manufacturing activities on behalf of FivePrime (each, a “Manufacturing Contractor”), subject to the following conditions: (a) selection of a Manufacturing Contractor shall be subject to the prior written approval of GSK; (b) GSK shall have the right to undertake an audit of any such potential Manufacturing Contractor prior to granting its approval and GSK’s approval may be expressly conditioned upon the remedy of any deficiencies noted in such audit to GSK’s satisfaction; (c) in the event that any deficiencies identified in an audit conducted pursuant to this Section 5.5.1(b) are unable to be cured, or are unable to be cured during a reasonable period of time, such proposed Manufacturing Contractor shall not be selected and GSK and FivePrime shall discuss in good faith alternative Manufacturing Contractors; and (d) in the event FivePrime selects a potential Manufacturing Contractor for such manufacturing

activities, GSK shall have the right, exercisable within *** Business Days after GSK’s approval of such Manufacturing Contractor, to elect to perform such manufacturing activities on behalf of FivePrime on the same material terms and conditions as negotiated by FivePrime with such potential Manufacturing Contractor. In connection with FivePrime’s identification, evaluation and selection of a potential Manufacturing Contractor, GSK agrees to discuss with FivePrime and to provide to FivePrime information, including whether any such Manufacturing Contractors under consideration have been approved by GSK, and GSK’s preferences with respect to the selection of a Manufacturing Contractor. In the event GSK manufactures and supplies any Clinical Lead Product (or ingredients thereof) to FivePrime under this Section 5.5.1, FivePrime shall have the right to undertake a reasonable technical and quality audit of GSK’s manufacturing facilities in connection therewith, in a manner that is customary for an IND sponsor to inspect drug substance and drug product manufacturing sites, in accordance with procedures to be agreed upon in advance by the Parties.

Promptly following GSK’s exercise of its PoM Option with respect to a Clinical Lead Target, FivePrime and GSK shall develop and reasonably agree upon a detailed supply transition plan to transfer to GSK at no additional costs all relevant Know-How, technology and inventory, including all information Controlled by FivePrime (including such information generated by FivePrime’s Manufacturing Contractors), related to the manufacture of the Clinical Lead Target and Clinical Lead Product, as applicable, within a reasonable period of time, not to exceed *** days after exercise of GSK’s PoM Option, such supply transition plan to include, at a minimum, the items set forth on the attached Exhibit F (the “Supply Transition Plan”). Prior to FivePrime entering into an agreement for the manufacture or supply of API or finished Clinical Lead Product with a Manufacturing Contractor in accordance with this Section 5.5, GSK and FivePrime will agree upon any costs to be allocated under such agreement for payment for consulting or other activities to be undertaken by the Manufacturing Contractor in connection with the Supply Transition Plan, provided that GSK would agree to bear all such costs allocated to payment for time incurred by the Manufacturing Contractor for consulting or other activities undertaken in connection with the Supply Transition Plan;

provided further, however, that GSK shall not be responsible for such amounts agreed between FivePrime and such Manufacturing Contractor without the approval of GSK. Each Party shall use its Commercially Reasonable Efforts to implement the Supply Transition Plan and to effect the transfer of such manufacturing responsibilities to GSK in an orderly manner.

Research Program Funding for Additional Assays.  In consideration for FivePrime’s performance of any additional Screening Assays GSK elects to

include in the Research Program pursuant to Section 3.2.2, GSK shall pay to FivePrime (a) *** dollars ($***) for each such Screening Assay that is a ***; and (b) *** dollars ($***) for each such Screening Assay that is a ***. Such payment(s) shall be made in equal quarterly installments over the remainder of the Research Program Term after the date on which GSK delivered the relevant Expansion Notice, as follows: FivePrime shall Invoice GSK, and GSK shall pay to FivePrime within *** days following receipt of such Invoice by GSK, such quarterly payment. It is the intent of the Parties that GSK will pay each such quarterly payments on the first day of each Calendar Quarter starting with the first (1^st) Calendar Quarter after the date on which GSK delivered the relevant Expansion Notice to FivePrime and that FivePrime may, accordingly, Invoice GSK for such quarterly payments *** days in advance of the start of a Calendar Quarter, provided, however, that GSK shall have no obligation to pay any such Invoiced amounts in less than *** days following receipt of such Invoice. For clarity, the maximum amount GSK may be required to pay under this Section 6.2.2 shall be *** dollars ($***), in the event that GSK elects to expand the Research Program to include ***.

Extraordinary Sample Expenses. GSK and FivePrime shall discuss and agree upon which Party shall be responsible for obtaining sufficient quantities of ***, as agreed upon by the Parties for use under the Research Program. GSK shall be responsible for obtaining sufficient quantities of *** samples as agreed upon by the Parties collectively, the “Extraordinary Samples”). GSK and FivePrime agree to share the costs, fees and expenses associated with the procurement of Extraordinary Samples (the “Extraordinary Sample Costs”) at the ratio of ***%:***% (GSK:FivePrime). The Parties agree that: (a) FivePrime’s obligation to share *** percent (***%) of the Extraordinary Sample Costs associated with *** by GSK shall be limited to those expenses paid by GSK after the Effective Date of this Agreement; (b) FivePrime’s total financial contribution to Extraordinary Sample Costs under this Agreement shall be capped at *** dollars ($***); (c) FivePrime’s total financial contribution to the Extraordinary Sample Costs incurred during each contract year (i.e., from the Effective Date to the first anniversary of the Effective Date, and then from each anniversary of the Effective Date to the subsequent Anniversary of the Effective Date) shall be capped at *** dollars ($***) for the first *** contract years and zero thereafter (the “Annual Cap”). In the event such Annual Cap is reached for any contract year, GSK shall pay for any excess amount that would otherwise be allocated to FivePrime but for such Annual Cap (the “Excess Amount”), and such Excess Amount shall be added to any Extraordinary Sample Costs allocated to FivePrime in subsequent contract year(s) to the extent the total Extraordinary Sample

Costs allocated to FivePrime in each such subsequent contract years do not exceed the Annual Cap. For clarity, GSK shall not have the obligation to make payment to FivePrime (beyond those set forth in Sections 6.2.1 and 6.2.2) for any of the following reagents if used by FivePrime under the Research Plan: ***.

Upon initiation of the first GLP toxicology study

Upon Initiation of a Phase 1 Clinical Trial

Upon Initiation of a Phase 2 Clinical Trial

Upon Initiation of a Phase 3 Clinical Trial

Upon acceptance of the first application for Marketing Authorization in the US

Upon acceptance of the first application for Marketing Authorization in the EU

Upon acceptance of the first application for Marketing Authorization in Japan

Upon acceptance of the first application for Marketing Authorization in China

Upon acceptance of the first application for Marketing Authorization in all of South America

First Commercial Sale in the US

First Commercial Sale in at least *** of the Major Markets

First Commercial Sale in Japan

First Commercial Sale in China

First Commercial Sale in all of South America

Upon initiation of the first GLP toxicology study

Upon Initiation of a Phase 1 Clinical Trial

Upon Initiation of a Phase 2 Clinical Trial

Upon Initiation of a Phase 3 Clinical Trial

Upon acceptance of the first application for Marketing Authorization in the US

Upon acceptance of the first application for Marketing Authorization in the EU

Upon acceptance of the first application for Marketing Authorization in Japan

Upon acceptance of the first application for Marketing Authorization in China

Upon acceptance of the first application for Marketing Authorization in all of South America

First Commercial Sale in the US

First Commercial Sale in at least *** of the Major Markets

First Commercial Sale in Japan

First Commercial Sale in China

First Commercial Sale in all of South America

Upon initiation of the first GLP toxicology study

Upon Initiation of a Phase 1 Clinical Trial

Upon Initiation of a Phase 2 Clinical Trial

Upon Initiation of a Phase 3 Clinical Trial

Upon acceptance of the first application for Marketing Authorization in the US

Upon acceptance of the first application for Marketing Authorization in the EU

Upon acceptance of the first application for Marketing Authorization in Japan

Upon acceptance of the first application for Marketing Authorization in China

Upon acceptance of the first application for Marketing Authorization in all of South America

First Commercial Sale in the US

First Commercial Sale in at least *** of the Major Markets in the EU

First Commercial Sale in Japan

First Commercial Sale in China

First Commercial Sale in all of South America

Upon initiation of the first GLP toxicology study

Upon Initiation of a Phase 1 Clinical Trial

Upon Initiation of a Phase 2 Clinical Trial

Upon Initiation of a Phase 3 Clinical Trial

Upon acceptance of the first application for Marketing Authorization in the US

Upon acceptance of the first application for Marketing Authorization in the EU

Upon acceptance of the first application for Marketing Authorization in Japan

Upon acceptance of the first application for Marketing Authorization in China

Upon acceptance of the first application for Marketing Authorization in all of South America

First Commercial Sale in the US

First Commercial Sale in at least *** of the Major Markets in the EU

First Commercial Sale in Japan

First Commercial Sale in China

First Commercial Sale in all of South America

Aggregate Worldwide Net Sales for a

Calendar Year

Portion of aggregate worldwide Net Sales for such Licensed Product that is less than *** Dollars ($***)

Portion of aggregate worldwide Net Sales for such Licensed Product that is equal to or greater than *** Dollars ($***) and less than *** Dollars ($***)

Portion of aggregate worldwide Net Sales for such Licensed Product that is equal to or greater than *** Dollars ($***)

Portion of aggregate worldwide Net Sales for such Licensed Product that is less than *** Dollars ($***)

Portion of aggregate worldwide Net Sales for such Licensed Product that is equal to or greater than *** Dollars ($***) and less than *** Dollars ($***)

Portion of aggregate worldwide Net Sales for such Licensed Product that is equal to or greater than *** Dollars ($***)

Portion of aggregate worldwide Net Sales for such Licensed Product that is less than *** Dollars ($***)

Portion of aggregate worldwide Net Sales for such Licensed Product that is equal to or greater than *** Dollars ($***) and less than *** Dollars ($***)

Portion of aggregate worldwide Net Sales for such Licensed Product that is equal to or greater than *** Dollars ($***)

Portion of aggregate worldwide Net Sales for such Licensed Product that is less than *** Dollars ($***)

Portion of aggregate worldwide Net Sales for such Licensed Product that is equal to or greater than *** Dollars ($***) and less than *** Dollars ($***)

Portion of aggregate worldwide Net Sales for such Licensed Product that is equal to or greater than *** Dollars ($***)

Reports; Payment of Royalty.  During the Term, and following the First Commercial Sale of any Licensed Product, GSK shall furnish to FivePrime a written report for the Calendar Quarter showing (i) for each of the Major Markets, on a Licensed Product-by-Licensed Product basis and for all Licensed Product(s) sold in the Territory during the reporting period and the royalties payable under this Agreement, the Net Sales and royalties due, and (ii) for all other sales outside of the Major Markets, on a Licensed Product-by-Licensed

Product basis and for all Licensed Product(s) sold in the Territory during the reporting period and the royalties payable under this Agreement, Net Sales, and royalties due. Reports shall be due on the *** day following the close of each Calendar Quarter. Royalties shown to have accrued by each royalty report shall be due and payable on the date such royalty report is due.

If such accounting firm correctly identifies an underpayment made by GSK during such period, GSK shall pay FivePrime *** percent (***%) of the amount of the underpayment, plus applicable interest as set forth in Section 6.6 above, within *** days of the date FivePrime delivers to GSK such accounting firm’s written report so concluding, or as otherwise agreed upon in writing by the Parties. The fees charged by such accounting firm shall be paid by FivePrime; provided, however, if such audit uncovers an underpayment by GSK that exceeds *** percent (***%) of the total payment due for the period under audit, then the fees of such accounting

firm shall be paid by GSK. In the event that the accounting firm uncovers an overpayment by GSK, then such overpayment by GSK shall be credited against any royalty payments owing in the Calendar Quarter following the Calendar Quarter in which such audit was completed, such future royalty payments to be adjusted accordingly on a carry-forward basis until such overpayment amount has been fully credited against future royalties owing to FivePrime.

Is required by applicable law, valid order of a court of competent jurisdiction, or judicial or administrative process, provided that the Receiving Party shall promptly inform the Disclosing Party of the disclosure that is being sought in order to provide the Disclosing Party,

where possible, an opportunity to challenge, limit or receive confidential treatment for the required disclosure, and further provided that the Receiving Party shall take all steps reasonably necessary to challenge, limit or receive confidential treatment for, the required disclosure.

Comment Rights.  In connection with the filing, prosecution and maintenance of Collaboration Patents set forth in Section 8.2.1(c) and (d), the filing Party shall give the non-filing Party an opportunity to review, prior to filing, the draft text of each Collaboration Patent application, and the draft text of each office action or substantive prosecution document (after the initial application is filed) for each such Collaboration Patent, shall consult with non-filing Party with respect thereto, shall take the non-filing Party’s reasonable written comments into account when finalizing such document, provided the non-filing Party promptly submits its written comments to allow the filing Party sufficient time to prepare and file its response and not lose its rights or reduce any patent term adjustment and shall supply the non-filing Party with a copy of the document as filed and with all substantive notices received from the relevant patent office with respect to such Collaboration Patent. The non-filing Party for such