VERSARTIS, INC. 2009 STOCK PLAN ADOPTED ON FEBRUARY 17, 2009 AS AMENDED ON MAY 13, 2009, SEPTEMBER 10,2010, FEBRUARY 14, 2011, JUNE 16, 2011, JANUARY 18,2012, MAY 1, 2012, OCTOBER 12, 2012, JANUARY 7, 2013, JULY 8, 2013, OCTOBER 1, 2013, DECEMBER 28, 2013, FEBRUARY 4, 2014 ANDFEBRUARY 14, 2014 TABLE OF CONTENTS

Exhibit 10.3

VERSARTIS, INC.

2009 STOCK PLAN

ADOPTED ON FEBRUARY 17, 2009

AS AMENDED ON MAY 13, 2009, SEPTEMBER 10, 2010, FEBRUARY 14, 2011, JUNE 16, 2011,

JANUARY 18, 2012, MAY 1, 2012, OCTOBER 12, 2012, JANUARY 7, 2013, JULY 8, 2013,

OCTOBER 1, 2013, DECEMBER 28, 2013, FEBRUARY 4, 2014 AND FEBRUARY 14, 2014

TABLE OF CONTENTS

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VERSARTIS, INC. 2009 STOCK PLAN

The purpose of the Plan is to offer selected persons an opportunity to acquire a proprietary interest in the success of the Company, or to increase such interest, by purchasing Shares of the Company’s Stock. The Plan provides both for the direct award or sale of Shares and for the grant of Options to purchase Shares. Options granted under the Plan may include Nonstatutory Options as well as ISOs intended to qualify under Section 422 of the Code.

Capitalized terms are defined in Section 12.

(a) Committees of the Board of Directors. The Plan may be administered by one or more Committees. Each Committee shall consist of one or more members of the Board of Directors who have been appointed by the Board of Directors. Each Committee shall have such authority and be responsible for such functions as the Board of Directors has assigned to it. If no Committee has been appointed, the entire Board of Directors shall administer the Plan. Any reference to the Board of Directors in the Plan shall be construed as a reference to the Committee (if any) to whom the Board of Directors has assigned a particular function.

(b) Authority of the Board of Directors. Subject to the provisions of the Plan, the Board of Directors shall have full authority and discretion to take any actions it deems necessary or advisable for the administration of the Plan. All decisions, interpretations and other actions of the Board of Directors shall be final and binding on all Purchasers, all Optionees and all persons deriving their rights from a Purchaser or Optionee.

(a) General Rule. Only Employees, Outside Directors and Consultants shall be eligible for the grant of Nonstatutory Options or the direct award or sale of Shares. Only Employees shall be eligible for the grant of ISOs.

(b) Ten-Percent Stockholders. A person who owns more than 10% of the total combined voting power of all classes of outstanding stock of the Company, its Parent or any of its Subsidiaries shall not be eligible for the grant of an ISO unless (i) the Exercise Price is at least 110% of the Fair Market Value of a Share on the date of grant and (ii) such ISO by its terms is not exercisable after the expiration of five years from the date of grant. For purposes of this Subsection (b), in determining stock ownership, the attribution rules of Section 424(d) of the Code shall be applied.

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(a) Basic Limitation. Not more than 29,474,164 Shares may be issued under the Plan (subject to Subsection (b) below and Section 8(a)). All of these Shares may be issued upon the exercise of ISOs. The number of Shares that are subject to Options or other rights outstanding at any time under the Plan shall not exceed the number of Shares that then remain available for issuance under the Plan. The Company, during the term of the Plan, shall at all times reserve and keep available sufficient Shares to satisfy the requirements of the Plan. Shares offered under the Plan may be authorized but unissued Shares or treasury Shares.

(b) Additional Shares. In the event that Shares previously issued under the Plan are reacquired by the Company, such Shares shall be added to the number of Shares then available for issuance under the Plan. In the event that an outstanding Option or other right for any reason expires or is canceled, the Shares allocable to the unexercised portion of such Option or other right shall be added to the number of Shares then available for issuance under the Plan.

(a) Stock Purchase Agreement. Each award or sale of Shares under the Plan (other than upon exercise of an Option) shall be evidenced by a Stock Purchase Agreement between the Purchaser and the Company. Such award or sale shall be subject to all applicable terms and conditions of the Plan and may be subject to any other terms and conditions which are not inconsistent with the Plan and which the Board of Directors deems appropriate for inclusion in a Stock Purchase Agreement. The provisions of the various Stock Purchase Agreements entered into under the Plan need not be identical.

(b) Duration of Offers and Nontransferability of Rights. Any right to acquire Shares under the Plan (other than an Option) shall automatically expire if not exercised by the Purchaser within 30 days after the grant of such right was communicated to the Purchaser by the Company. Such right shall not be transferable and shall be exercisable only by the Purchaser to whom such right was granted.

(c) Purchase Price. The Board of Directors shall determine the Purchase Price of Shares to be offered under the Plan at its sole discretion. The Purchase Price shall be payable in a form described in Section 7.

(d) Withholding Taxes. As a condition to the purchase of Shares, the Purchaser shall make such arrangements as the Board of Directors may require for the satisfaction of any federal, state, local or foreign withholding tax obligations that may arise in connection with such purchase.

(e) Restrictions on Transfer of Shares. Any Shares awarded or sold under the Plan shall be subject to such special forfeiture conditions, rights of repurchase, rights of first refusal and other transfer restrictions as the Board of Directors may determine. Such restrictions shall be set forth in the applicable Stock Purchase Agreement and shall apply in addition to any restrictions that may apply to holders of Shares generally.

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(a) Stock Option Agreement. Each grant of an Option under the Plan shall be evidenced by a Stock Option Agreement between the Optionee and the Company. The Option shall be subject to all applicable terms and conditions of the Plan and may be subject to any other terms and conditions which are not inconsistent with the Plan and which the Board of Directors deems appropriate for inclusion in a Stock Option Agreement. The provisions of the various Stock Option Agreements entered into under the Plan need not be identical.

(b) Number of Shares. Each Stock Option Agreement shall specify the number of Shares that are subject to the Option and shall provide for the adjustment of such number in accordance with Section 8. The Stock Option Agreement shall also specify whether the Option is an ISO or a Nonstatutory Option.

(c) Exercise Price. Each Stock Option Agreement shall specify the Exercise Price. The Exercise Price of any Option shall not be less than 100% of the Fair Market Value of a Share on the date of grant, and in the case of an ISO a higher percentage may be required by Section 3(b). Subject to the preceding sentence, the Exercise Price shall be determined by the Board of Directors at its sole discretion. The Exercise Price shall be payable in a form described in Section 7.

(d) Exercisability. Each Stock Option Agreement shall specify the date when all or any installment of the Option is to become exercisable. No Option shall be exercisable unless the Optionee (i) has delivered an executed copy of the Stock Option Agreement to the Company or (ii) otherwise agrees to be bound by the terms of the Stock Option Agreement. The Board of Directors shall determine the exercisability provisions of the Stock Option Agreement at its sole discretion. All of an Optionee’s Options shall become exercisable in full if Section 8(b)(iv) applies.

(e) Basic Term. The Stock Option Agreement shall specify the term of the Option. The term shall not exceed 10 years from the date of grant, and in the case of an ISO a shorter term may be required by Section 3(b). Subject to the preceding sentence, the Board of Directors at its sole discretion shall determine when an Option is to expire.

(f) Termination of Service (Except by Death). If an Optionee’s Service terminates for any reason other than the Optionee’s death, then the Optionee’s Options shall expire on the earliest of the following occasions:

(i) The expiration date determined pursuant to Subsection (e) above;

(ii) The date three months after the termination of the Optionee’s Service for any reason other than Disability, or such later date as the Board of Directors may determine; or

(iii) The date six months after the termination of the Optionee’s Service by reason of Disability, or such later date as the Board of Directors may determine.

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The Optionee may exercise all or part of the Optionee’s Options at any time before the expiration of such Options under the preceding sentence, but only to the extent that such Options had become exercisable before the Optionee’s Service terminated (or became exercisable as a result of the termination) and the underlying Shares had vested before the Optionee’s Service terminated (or vested as a result of the termination). The balance of such Options shall lapse when the Optionee’s Service terminates. In the event that the Optionee dies after the termination of the Optionee’s Service but before the expiration of the Optionee’s Options, all or part of such Options may be exercised (prior to expiration) by the executors or administrators of the Optionee’s estate or by any person who has acquired such Options directly from the Optionee by beneficiary designation, bequest or inheritance, but only to the extent that such Options had become exercisable before the Optionee’s Service terminated (or became exercisable as a result of the termination) and the underlying Shares had vested before the Optionee’s Service terminated (or vested as a result of the termination).

(g) Leaves of Absence. For purposes of Subsection (f) above, Service shall be deemed to continue while the Optionee is on a bona fide leave of absence, if such leave was approved by the Company in writing and if continued crediting of Service for this purpose is expressly required by the terms of such leave or by applicable law (as determined by the Company).

(h) Death of Optionee. If an Optionee dies while the Optionee is in Service, then the Optionee’s Options shall expire on the earlier of the following dates:

(i) The expiration date determined pursuant to Subsection (e) above; or

(ii) The date 12 months after the Optionee’s death, or such later date as the Board of Directors may determine.

All or part of the Optionee’s Options may be exercised at any time before the expiration of such Options under the preceding sentence by the executors or administrators of the Optionee’s estate or by any person who has acquired such Options directly from the Optionee by beneficiary designation, bequest or inheritance, but only to the extent that such Options had become exercisable before the Optionee’s death (or became exercisable as a result of the death) and the underlying Shares had vested before the Optionee’s death (or vested as a result of the Optionee’s death). The balance of such Options shall lapse when the Optionee dies.

(i) Restrictions on Transfer of Shares. Any Shares issued upon exercise of an Option shall be subject to such special forfeiture conditions, rights of repurchase, rights of first refusal and other transfer restrictions as the Board of Directors may determine. Such restrictions shall be set forth in the applicable Stock Option Agreement and shall apply in addition to any restrictions that may apply to holders of Shares generally.

(j) Transferability of Options. An Option shall be transferable by the Optionee only by (i) a beneficiary designation, (ii) a will or (iii) the laws of descent and distribution, except as provided in the next sentence. If the applicable Stock Option Agreement so provides, a Nonstatutory Option shall also be transferable by gift or domestic relations order to a Family Member of the Optionee. An ISO may be exercised during the lifetime of the Optionee only by the Optionee or by the Optionee’s guardian or legal representative.

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(k) Withholding Taxes. As a condition to the exercise of an Option, the Optionee shall make such arrangements as the Board of Directors may require for the satisfaction of any federal, state, local or foreign withholding tax obligations that may arise in connection with such exercise. The Optionee shall also make such arrangements as the Board of Directors may require for the satisfaction of any federal, state, local or foreign withholding tax obligations that may arise in connection with the disposition of Shares acquired by exercising an Option.

(l) No Rights as a Stockholder. An Optionee, or a transferee of an Optionee, shall have no rights as a stockholder with respect to any Shares covered by the Optionee’s Option until such person becomes entitled to receive such Shares by filing a notice of exercise and paying the Exercise Price pursuant to the terms of such Option.

(m) Modification, Extension and Assumption of Options. Within the limitations of the Plan, the Board of Directors may modify, extend or assume outstanding Options or may accept the cancellation of outstanding Options (whether granted by the Company or another issuer) in return for the grant of new Options for the same or a different number of Shares and at the same or a different Exercise Price. The foregoing notwithstanding, no modification of an Option shall, without the consent of the Optionee, impair the Optionee’s rights or increase the Optionee’s obligations under such Option.

(a) General Rule. The entire Purchase Price or Exercise Price of Shares issued under the Plan shall be payable in cash or cash equivalents at the time when such Shares are purchased, except as otherwise provided in this Section 7.

(b) Services Rendered. At the discretion of the Board of Directors, Shares may be awarded under the Plan in consideration of services rendered to the Company, a Parent or a Subsidiary prior to the award.

(c) Promissory Note. At the discretion of the Board of Directors, all or a portion of the Purchase Price or Exercise Price (as the case may be) of Shares issued under the Plan may be paid with a full-recourse promissory note. The Shares shall be pledged as security for payment of the principal amount of the promissory note and interest thereon. The interest rate payable under the terms of the promissory note shall not be less than the minimum rate (if any) required to avoid the imputation of additional interest under the Code. Subject to the foregoing, the Board of Directors (at its sole discretion) shall specify the term, interest rate, amortization requirements (if any) and other provisions of such note.

(d) Surrender of Stock. At the discretion of the Board of Directors, all or any part of the Exercise Price may be paid by surrendering, or attesting to the ownership of, Shares that are already owned by the Optionee. Such Shares shall be surrendered to the Company in good form for transfer and shall be valued at their Fair Market Value as of the date when the Option is exercised.

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(e) Exercise/Sale. To the extent that a Stock Option Agreement so provides, and if Stock is publicly traded, all or part of the Exercise Price and any withholding taxes may be paid by the delivery (on a form prescribed by the Company) of an irrevocable direction to a securities broker approved by the Company to sell Shares and to deliver all or part of the sales proceeds to the Company.

(f) Other Forms of Payment. To the extent that a Stock Purchase Agreement or Stock Option Agreement so provides, the Purchase Price or Exercise Price of Shares issued under the Plan may be paid in any other form permitted by the Delaware General Corporation Law, as amended.

(a) General. In the event of a subdivision of the outstanding Stock, a declaration of a dividend payable in Shares, a combination or consolidation of the outstanding Stock into a lesser number of Shares, a reclassification, or any other increase or decrease in the number of issued shares of Stock effected without receipt of consideration by the Company, proportionate adjustments shall automatically be made in each of (i) the number of Shares available for future grants under Section 4, (ii) the number of Shares covered by each outstanding Option and (iii) the Exercise Price under each outstanding Option. In the event of a declaration of an extraordinary dividend payable in a form other than Shares in an amount that has a material effect on the Fair Market Value of the Stock, a recapitalization, a spin-off, or a similar occurrence, the Board of Directors at its sole discretion may make appropriate adjustments in one or more of (i) the number of Shares available for future grants under Section 4, (ii) the number of Shares covered by each outstanding Option or (iii) the Exercise Price under each outstanding Option; provided, however, that the Board of Directors shall in any event make such adjustments as may be required by Section 25102(o) of the California Corporations Code.

(b) Change in Control.

(i) In the event of a Change in Control, the Shares subject to each Option granted to an Employee, Consultant or Outside Director that are outstanding under the Plan at the time of the Change in Control shall automatically become 100% fully vested, and each such Option shall become, immediately prior to the consummation of the Change in Control, exercisable for 100% of the Shares at the time subject to that Option, but only if and to the extent such Option is not assumed by the successor entity or otherwise not continued in full force and effect pursuant to the terms of the Change in Control transaction. In the event of a Change in Control, the Shares subject to an outstanding Option granted to an Employee, Consultant or Outside Director, which Option has been assumed by the successor entity or otherwise continued in full force and effect pursuant to the terms of the Change in Control transaction, shall automatically become 100% fully vested, and each such Option shall become exercisable for all Shares at the time subject to that Option, but only upon the occurrence and at the time of Optionee’s Involuntary Termination.

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(ii) Immediately prior to the consummation of a Change in Control, all outstanding repurchase rights of the Company related to any Option granted to an Employee, Consultant or Outside Director and set forth in an applicable Stock Purchase Agreement shall automatically terminate.

(iii) Immediately following the consummation of the Change in Control, all outstanding Options shall terminate and cease to be outstanding, except to the extent assumed by the successor entity or otherwise continued in full force and effect pursuant to the terms of the Change in Control transaction.

(iv) Each Option that is assumed in connection with a Change in Control or otherwise continued in full force and effect pursuant to the terms of the Change in Control transaction shall be appropriately adjusted, immediately after the consummation of such Change in Control, to apply to the number and class of securities that would have been issuable to the Optionee upon consummation of such Change in Control, had the Option been exercised immediately prior to such Change in Control. Appropriate adjustments to reflect such Change in Control transaction shall also be made to (1) the number and class of securities available for issuance under the Plan following the consummation of such Change in Control and (2) the exercise price payable per share under each outstanding Option, provided the aggregate exercise price payable for such securities shall remain the same.

(v) The portion of any ISO accelerated in connection with a Change in Control shall remain exercisable as an ISO only to the extent the applicable $100,000 limitation under Section 422(d) of the Code is not exceeded. To the extent such dollar limitation is exceeded, the accelerated portion of such Option shall be exercisable as a Nonstatutory Option under the federal tax laws.”

(vi) The acceleration and exercisability of Options in the event of a Change in Control are subject to other limitations imposed by the administrator of the Plan.

(c) Reservation of Rights. Except as provided in this Section 8, an Optionee or Purchaser shall have no rights by reason of (i) any subdivision or consolidation of shares of stock of any class, (ii) the payment of any dividend or (iii) any other increase or decrease in the number of shares of stock of any class. Any issuance by the Company of shares of stock of any class, or securities convertible into shares of stock of any class, shall not affect, and no adjustment by reason thereof shall be made with respect to, the number or Exercise Price of Shares subject to an Option. The grant of an Option pursuant to the Plan shall not affect in any way the right or power of the Company to make adjustments, reclassifications, reorganizations or changes of its capital or business structure, to merge or consolidate or to dissolve, liquidate, sell or transfer all or any part of its business or assets.

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Shares shall not be issued under the Plan unless the issuance and delivery of such Shares comply with (or are exempt from) all applicable requirements of law, including (without limitation) the Securities Act of 1933, as amended, the rules and regulations promulgated thereunder, state securities laws and regulations, and the regulations of any stock exchange or other securities market on which the Company’s securities may then be traded.

Nothing in the Plan or in any right or Option granted under the Plan shall confer upon the Purchaser or Optionee any right to continue in Service for any period of specific duration or interfere with or otherwise restrict in any way the rights of the Company (or any Parent or Subsidiary employing or retaining the Purchaser or Optionee) or of the Purchaser or Optionee, which rights are hereby expressly reserved by each, to terminate his or her Service at any time and for any reason, with or without cause.

(a) Term of the Plan. The Plan, as set forth herein, shall become effective on the date of its adoption by the Board of Directors, subject to the approval of the Company’s stockholders. If the stockholders fail to approve the Plan within 12 months after its adoption by the Board of Directors, then any grants, exercises or sales that have already occurred under the Plan shall be rescinded and no additional grants, exercises or sales shall thereafter be made under the Plan. The Plan shall terminate automatically 10 years after the later of (i) the date when the Board of Directors adopted the Plan or (ii) the date when the Board of Directors approved the most recent increase in the number of Shares reserved under Section 4 that was also approved by the Company’s stockholders. The Plan may be terminated on any earlier date pursuant to Subsection (b) below.

(b) Right to Amend or Terminate the Plan. The Board of Directors may amend, suspend or terminate the Plan at any time and for any reason; provided, however, that any amendment of the Plan shall be subject to the approval of the Company’s stockholders if it (i) increases the number of Shares available for issuance under the Plan (except as provided in Section 8) or (ii) materially changes the class of persons who are eligible for the grant of ISOs. Stockholder approval shall not be required for any other amendment of the Plan. If the stockholders fail to approve an increase in the number of Shares reserved under Section 4 within 12 months after its adoption by the Board of Directors, then any grants, exercises or sales that have already occurred in reliance on such increase shall be rescinded and no additional grants, exercises or sales shall thereafter be made in reliance on such increase.

(c) Effect of Amendment or Termination. No Shares shall be issued or sold under the Plan after the termination thereof, except upon exercise of an Option granted prior to such termination. The termination of the Plan, or any amendment thereof, shall not affect any Share previously issued or any Option previously granted under the Plan.

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(a) “Board of Directors” shall mean the Board of Directors of the Company, as constituted from time to time.

(b) “Change in Control” shall mean a change in ownership or control of the Company effected through any of the following transactions:

(i) a merger, consolidation or other reorganization in which securities representing more than 50% of the total combined voting power of the Company’s outstanding securities are beneficially owned, directly or indirectly, by a person or persons different from the person or persons who beneficially owned those securities immediately prior to such transaction, except that any such transaction effected in connection with or to facilitate a private financing of the Company that is approved by the Board of Directors shall not be deemed to be a Change in Control unless otherwise determined by the Board of Directors;

(ii) a sale, transfer or other disposition of all or substantially all of the Company’s assets; or

(iii) any “person” (as such term is used in Sections 13(d) and 14(d) of the Exchange Act) becomes the “beneficial owner” (as defined in Rule 13d-3 under the Exchange Act), directly or indirectly, of securities of the Company representing fifty percent (50%) or more of the total voting power represented by the Company’s then outstanding voting securities, except that any change in the beneficial ownership of the securities of the Company as a result of a private financing of the Company that is approved by the Board of Directors shall not be deemed to be a Change in Control.

In no event shall any public offering of the Company’s securities be deemed to constitute a Change in Control.

(c) “Code” shall mean the Internal Revenue Code of 1986, as amended.

(d) “Committee” shall mean a committee of the Board of Directors, as described in Section 2(a).

(e) “Company” shall mean Versartis, Inc., a Delaware corporation.

(f) “Consultant” shall mean a person who performs bona fide services for the Company, a Parent or a Subsidiary as a consultant or advisor, excluding Employees and Outside Directors.

(g) “Disability” shall mean that the Optionee is unable to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment.

(h) “Employee” shall mean any individual who is a common-law employee of the Company, a Parent or a Subsidiary.

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(i) “Exchange Act” shall mean the Securities Exchange Act of 1934, as amended.

(j) “Exercise Price” shall mean the amount for which one Share may be purchased upon exercise of an Option, as specified by the Board of Directors in the applicable Stock Option Agreement.

(k) “Fair Market Value” shall mean the fair market value of a Share, as determined by the Board of Directors in accordance with applicable law. Such determination shall be conclusive and binding on all persons.

(1) “Family Member” shall mean (i) any child, stepchild, grandchild, parent, stepparent, grandparent, spouse, former spouse, sibling, niece, nephew, mother-in-law, father-in law, son-in-law, daughter-in-law, brother-in-law or sister-in-law, including adoptive relationships, (ii) any person sharing the Optionee’s household (other than a tenant or employee), (iii) a trust in which persons described in Clause (i) or (ii) have more than 50% of the beneficial interest, (iv) a foundation in which persons described in Clause (i) or (ii) or the Optionee control the management of assets and (v) any other entity in which persons described in Clause (i) or (ii) or the Optionee own more than 50% of the voting interests.

(m) “Involuntary Termination” shall mean, during the twelve (12) months following the consummation of a Change in Control,

(i) the termination of Optionee’s Service by reason of Optionee’s involuntary dismissal or discharge by the Company or Parent or Subsidiary employing Optionee for reasons other than Misconduct, or

(ii) Optionee’s voluntary resignation following (A) a material diminution in the Optionee’s base compensation, (B) a material diminution in the Optionee’s authority, duties, position or responsibilities, (C) a material diminution in the authority, duties, position or responsibilities of the supervisor to whom the Optionee is required to report, including a requirement that the Optionee report to a corporate officer or employee instead of directly to the Board of Directors, (D) a material diminution in the budget over which the Optionee retains authority, (E) a relocation of Optionee’s principal place of work to a location that is more than 50 miles away from the Optionee’s principal place of work immediately prior to the consummation of a Change in Control, or (F) any other action or inaction that constitutes a material breach by the Company of this Plan.

(n) “ISO” shall mean an employee incentive stock option described in Section 422(b) of the Code.

(o) “Misconduct” shall mean (i) Optionee’s repeated failure to substantially perform his duties and responsibilities to the Company or deliberate violation of significant Company policies, (ii) the commission of any act of fraud, embezzlement or dishonesty by the Optionee, (iii) any unauthorized use or disclosure by Optionee of confidential information or trade secrets of the Company (or any Parent or Subsidiary), or (iv) any other intentional misconduct by Optionee adversely affecting the business or affairs of the Company (or any

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Parent or Subsidiary) in a material manner; provided, however, that if the term or concept has been defined in a written employment agreement between the Company and the Optionee, then Misconduct shall have the definition set forth in such employment agreement while such employment agreement is in effect. The foregoing definition shall not in any way preclude or restrict the right of the Company (or any Parent or Subsidiary) to discharge or dismiss any Optionee or other person in the Service of the Company (or any Parent or Subsidiary) for any other acts or omissions, but such other acts or omissions shall not be deemed, for purposes of the Plan, to constitute grounds for termination for Misconduct.

(p) “Nonstatutory Option” shall mean a stock option not described in Sections 422(b) or 423(b) of the Code.

(q) “Option” shall mean an ISO or Nonstatutory Option granted under the Plan and entitling the holder to purchase Shares.

(r) “Optionee” shall mean a person who holds an Option.

(s) “Outside Director” shall mean a member of the Board of Directors who is not an Employee.

(t) “Parent” shall mean any corporation (other than the Company) in an unbroken chain of corporations ending with the Company, if each of the corporations other than the Company owns stock possessing 50% or more of the total combined voting power of all classes of stock in one of the other corporations in such chain. A corporation that attains the status of a Parent on a date after the adoption of the Plan shall be considered a Parent commencing as of such date.

(u) “Plan” shall mean this Versartis, Inc. 2009 Stock Plan.

(v) “Purchase Price” shall mean the consideration for which one Share may be acquired under the Plan (other than upon exercise of an Option), as specified by the Board of Directors.

(w) “Purchaser” shall mean a person to whom the Board of Directors has offered the right to acquire Shares under the Plan (other than upon exercise of an Option).

(x) “Service” shall mean service as an Employee, Outside Director or Consultant.

(y) “Share” shall mean one share of Stock, as adjusted in accordance with Section 8 (if applicable).

(z) “Stock” shall mean the Common Stock of the Company.

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(aa) “Stock Option Agreement” shall mean the agreement between the Company and an Optionee that contains the terms, conditions and restrictions pertaining to the Optionee’s Option.

(bb) “Stock Purchase Agreement” shall mean the agreement between the Company and a Purchaser who acquires Shares under the Plan that contains the terms, conditions and restrictions pertaining to the acquisition of such Shares.

(cc) “Subsidiary” shall mean any corporation (other than the Company) in an unbroken chain of corporations beginning with the Company, if each of the corporations other than the last corporation in the unbroken chain owns stock possessing 50% or more of the total combined voting power of all classes of stock in one of the other corporations in such chain. A corporation that attains the status of a Subsidiary on a date after the adoption of the Plan shall be considered a Subsidiary commencing as of such date.

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