ARDELYX, INC. 2014EQUITY INCENTIVE AWARD PLAN RESTRICTED STOCK UNIT AWARD GRANT NOTICE

Exhibit 10.6(c)

ARDELYX, INC.

2014 EQUITY INCENTIVE AWARD PLAN

RESTRICTED STOCK UNIT AWARD GRANT NOTICE

Ardelyx, Inc., a Delaware corporation, (the “Company”), pursuant to its 2014 Equity Incentive Award Plan, as amended from time to time (the “Plan”), hereby grants to the holder listed below (the “Participant”), an award of restricted stock units (“Restricted Stock Units” or “RSUs”). Each vested Restricted Stock Unit represents the right to receive, in accordance with the Restricted Stock Unit Award Agreement attached hereto as Exhibit A (the “Agreement”), one share of Common Stock (“Share”). This award of Restricted Stock Units is subject to all of the terms and conditions set forth herein and in the Agreement and the Plan, each of which are incorporated herein by reference. Unless otherwise defined herein, the terms defined in the Plan shall have the same defined meanings in this Restricted Stock Unit Award Grant Notice (the “Grant Notice”) and the Agreement.

By his or her signature and the Company’s signature below, the Participant agrees to be bound by the terms and conditions of the Plan, the Agreement and this Grant Notice. The Participant has reviewed the Agreement, the Plan and this Grant Notice in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Grant Notice and fully understands all provisions of this Grant Notice, the Agreement and the Plan. The Participant hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Administrator upon any questions arising under the Plan, this Grant Notice or the Agreement. In addition, by signing below, the Participant also agrees that the Company, in its sole discretion, may satisfy any withholding obligations in accordance with Section 2.6(b) of the Agreement by (i) withholding shares of Common Stock otherwise issuable to the Participant upon vesting of the RSUs, (ii) instructing a broker on the Participant’s behalf to sell shares of Common Stock otherwise issuable to the Participant upon vesting of the RSUs and submit the proceeds of such sale to the Company, or (iii) using any other method permitted by Section 2.6(b) of the Agreement or the Plan.

EXHIBIT A

TO RESTRICTED STOCK UNIT AWARD GRANT NOTICE

RESTRICTED STOCK UNIT AWARD AGREEMENT

Pursuant to the Restricted Stock Unit Award Grant Notice (the “Grant Notice”) to which this Restricted Stock Unit Award Agreement (this “Agreement”) is attached, Ardelyx, Inc., a Delaware corporation (the “Company”), has granted to the Participant the number of restricted stock units (“Restricted Stock Units” or “RSUs”) set forth in the Grant Notice under the Company’s 2014 Equity Incentive Award Plan, as amended from time to time (the “Plan”). Each vested Restricted Stock Unit represents the right to receive one share of Common Stock (“Share”). Capitalized terms not specifically defined herein shall have the meanings specified in the Plan and Grant Notice.

ARTICLE I.

GENERAL

1.1 Incorporation of Terms of Plan. The RSUs are subject to the terms and conditions of the Plan, which are incorporated herein by reference. In the event of any inconsistency between the Plan and this Agreement, the terms of the Plan shall control.

ARTICLE II.

GRANT OF RESTRICTED STOCK UNITS

2.1 Grant of RSUs. Pursuant to the Grant Notice and upon the terms and conditions set forth in the Plan and this Agreement, effective as of the Grant Date set forth in the Grant Notice, the Company hereby grants to the Participant an award of RSUs under the Plan in consideration of the Participant’s past and/or continued employment with or service to the Company or any Affiliates and for other good and valuable consideration.

2.2 Unsecured Obligation to RSUs. Unless and until the RSUs have vested in the manner set forth in Article 2 hereof, the Participant will have no right to receive Common Stock under any such RSUs. Prior to actual payment of any vested RSUs, such RSUs will represent an unsecured obligation of the Company, payable (if at all) only from the general assets of the Company.

2.3 Vesting Schedule. Subject to Section 2.5 hereof, the RSUs shall vest and become nonforfeitable with respect to the applicable portion thereof according to the vesting schedule set forth in the Grant Notice (rounding down to the nearest whole Share).

2.4 Consideration to the Company. In consideration of the grant of the award of RSUs pursuant hereto, the Participant agrees to render faithful and efficient services to the Company or any Affiliate.

2.5 Forfeiture, Termination and Cancellation upon Termination of Service. Notwithstanding any contrary provision of this Agreement or the Plan, upon the Participant’s Termination of Service for any or no reason, all Restricted Stock Units which have not vested prior to or in connection with such Termination of Service (after taking into consideration any accelerated vesting which may occur in connection with such Termination of Service (if any)) shall thereupon automatically be forfeited, terminated and cancelled as of the applicable termination date without payment of any consideration by the Company, and the Participant, or the Participant’s beneficiary or personal representative, as the case may be, shall have no further rights hereunder. No portion of the RSUs which has not become vested as of the date on which the Participant incurs a Termination of Service shall thereafter become vested.

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2.6 Issuance of Common Stock upon Vesting.

(a) As soon as administratively practicable following the vesting of any Restricted Stock Units pursuant to Section 2.3 hereof, but in no event later than thirty (30) days after such vesting date (for the avoidance of doubt, this deadline is intended to comply with the “short term deferral” exemption from Section 409A of the Code), the Company shall deliver to the Participant (or any transferee permitted under Section 3.2 hereof) a number of Shares (either by delivering one or more certificates for such Shares or by entering such Shares in book entry form, as determined by the Company in its sole discretion) equal to the number of RSUs subject to this Award that vest on the applicable vesting date, unless such RSUs terminate prior to the given vesting date pursuant to Section 2.5 hereof. Notwithstanding the foregoing, in the event Shares cannot be issued pursuant to Section 12.4 of the Plan, the Shares shall be issued pursuant to the preceding sentence as soon as administratively practicable after the Administrator determines that Shares can again be issued in accordance with such Section.

(b) As set forth in Section 12.2 of the Plan, the Company shall have the authority and the right to deduct or withhold, or to require the Participant to remit to the Company, an amount sufficient to satisfy all applicable federal, state and local taxes required by law to be withheld with respect to any taxable event arising in connection with the Restricted Stock Units. The Company shall not be obligated to deliver any new certificate representing Shares to the Participant or the Participant’s legal representative or enter such Shares in book entry form unless and until the Participant or the Participant’s legal representative shall have paid or otherwise satisfied in full the amount of all federal, state and local taxes applicable to the taxable income of the Participant resulting from the grant or vesting of the Restricted Stock Units or the issuance of Shares.

2.7 Conditions to Delivery of Shares. The Shares deliverable hereunder may be either previously authorized but unissued Shares, treasury Shares or issued Shares which have then been reacquired by the Company. Such Shares shall be fully paid and nonassessable. The Company shall not be required to issue or deliver any certificates or make any book entries evidencing Shares deliverable hereunder prior to fulfillment of the conditions set forth in Section 12.4 of the Plan.

2.8 Rights as Stockholder. The holder of the RSUs shall not be, nor have any of the rights or privileges of, a stockholder of the Company, including, without limitation, voting rights and rights to dividends, in respect of the RSUs and any Shares underlying the RSUs and deliverable hereunder unless and until such Shares shall have been issued by the Company and held of record by such holder (as evidenced by the appropriate entry on the books of the Company or of a duly authorized transfer agent of the Company). No adjustment shall be made for a dividend or other right for which the record date is prior to the date the Shares are issued, except as provided in Section 14.2 of the Plan.

ARTICLE III.

OTHER PROVISIONS

3.1 Administration. The Administrator shall have the power to interpret the Plan and this Agreement and to adopt such rules for the administration, interpretation and application of the Plan as are consistent therewith and to interpret, amend or revoke any such rules. All actions taken and all interpretations and determinations made by the Administrator in good faith shall be final and binding upon the Participant, the Company and all other interested persons. No member of the Administrator or the Board shall be personally liable for any action, determination or interpretation made in good faith with respect to the Plan, this Agreement or the RSUs.

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3.2 RSUs Not Transferable. The RSUs shall be subject to the restrictions on transferability set forth in Section 12.3 of the Plan; provided, however, that this Section 3.2 notwithstanding, with the consent of the Administrator, the RSUs may be transferred to one or more Permitted Transferees, subject to and in accordance with Section 12.3 of the Plan.

3.3 Tax Consultation. The Participant understands that the Participant may suffer adverse tax consequences in connection with the RSUs granted pursuant to this Agreement (and the Shares issuable with respect thereto). The Participant represents that the Participant has consulted with any tax consultants the Participant deems advisable in connection with the RSUs and the issuance of Shares with respect thereto and that the Participant is not relying on the Company for any tax advice.

3.4 Binding Agreement. Subject to the limitation on the transferability of the RSUs contained herein, this Agreement will be binding upon and inure to the benefit of the heirs, legatees, legal representatives, successors and assigns of the parties hereto.

3.5 Adjustments Upon Specified Events. The Administrator may accelerate the vesting of the RSUs in such circumstances as it, in its sole discretion, may determine. The Participant acknowledges that the RSUs are subject to adjustment, modification and termination in certain events as provided in this Agreement and Section 14.2 of the Plan.

3.6 Notices. Any notice to be given under the terms of this Agreement to the Company shall be addressed to the Company in care of the Secretary of the Company at the Company’s principal office, and any notice to be given to the Participant shall be addressed to the Participant at the Participant’s last address reflected on the Company’s records. By a notice given pursuant to this Section 3.6, either party may hereafter designate a different address for notices to be given to that party. Any notice shall be deemed duly given when sent via email or when sent by certified mail (return receipt requested) and deposited (with postage prepaid) in a post office or branch post office regularly maintained by the United States Postal Service.

3.7 Participant’s Representations. If the Shares issuable hereunder have not been registered under the Securities Act or any applicable state laws on an effective registration statement at the time of such issuance, the Participant shall, if required by the Company, concurrently with such issuance, make such written representations as are deemed necessary or appropriate by the Company and/or its counsel.

3.8 Titles. Titles are provided herein for convenience only and are not to serve as a basis for interpretation or construction of this Agreement.

3.9 Governing Law. The laws of the State of Delaware shall govern the interpretation, validity, administration, enforcement and performance of the terms of this Agreement regardless of the law that might be applied under principles of conflicts of laws.

3.10 Conformity to Securities Laws. The Participant acknowledges that the Plan and this Agreement are intended to conform to the extent necessary with all provisions of the Securities Act and the Exchange Act and any other Applicable Law. Notwithstanding anything herein to the contrary, the Plan shall be administered, and the RSUs are granted, only in such a manner as to conform to Applicable Law. To the extent permitted by Applicable Law, the Plan and this Agreement shall be deemed amended to the extent necessary to conform to such Applicable Law.

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3.11 Amendment, Suspension and Termination. To the extent permitted by the Plan, this Agreement may be wholly or partially amended or otherwise modified, suspended or terminated at any time or from time to time by the Administrator or the Board; provided, however, that, except as may otherwise be provided by the Plan, no amendment, modification, suspension or termination of this Agreement shall adversely affect the RSUs in any material way without the prior written consent of the Participant.

3.12 Successors and Assigns. The Company may assign any of its rights under this Agreement to single or multiple assignees, and this Agreement shall inure to the benefit of the successors and assigns of the Company. Subject to the restrictions on transfer herein set forth in Section 3.2 hereof, this Agreement shall be binding upon the Participant and his or her heirs, executors, administrators, successors and assigns.

3.13 Limitations Applicable to Section 16 Persons. Notwithstanding any other provision of the Plan or this Agreement, if the Participant is subject to Section 16 of the Exchange Act, then the Plan, the RSUs and this Agreement shall be subject to any additional limitations set forth in any applicable exemptive rule under Section 16 of the Exchange Act (including any amendment to Rule 16b-3 of the Exchange Act) that are requirements for the application of such exemptive rule. To the extent permitted by Applicable Law, this Agreement shall be deemed amended to the extent necessary to conform to such applicable exemptive rule.

3.14 Not a Contract of Service Relationship. Nothing in this Agreement or in the Plan shall confer upon Participant any right to continue to serve as an employee or other service provider of the Company or any of its Affiliates or interfere with or restrict in any way with the right of the Company or any of its Affiliates, which rights are hereby expressly reserved, to discharge or to terminate for any reason whatsoever, with or without cause, the services of the Participant’s at any time.

3.15 Entire Agreement. The Plan, the Grant Notice and this Agreement (including all Exhibits thereto, if any) constitute the entire agreement of the parties and supersede in their entirety all prior undertakings and agreements of the Company and the Participant with respect to the subject matter hereof.

3.16 Section 409A. This Award is not intended to constitute “nonqualified deferred compensation” within the meaning of Section 409A of the Code (together with any Department of Treasury regulations and other interpretive guidance issued thereunder, including without limitation any such regulations or other guidance that may be issued after the date hereof, “Section 409A”). However, notwithstanding any other provision of the Plan, the Grant Notice or this Agreement, if at any time the Administrator determines that this Award (or any portion thereof) may be subject to Section 409A, the Administrator shall have the right in its sole discretion (without any obligation to do so or to indemnify Participant or any other person for failure to do so) to adopt such amendments to the Plan, the Grant Notice or this Agreement, or adopt other policies and procedures (including amendments, policies and procedures with retroactive effect), or take any other actions, as the Administrator determines are necessary or appropriate for this Award either to be exempt from the application of Section 409A or to comply with the requirements of Section 409A.

3.17 Limitation on Participant’s Rights. Participation in the Plan confers no rights or interests other than as herein provided. This Agreement creates only a contractual obligation on the part of the Company as to amounts payable and shall not be construed as creating a trust. Neither the Plan nor any underlying program, in and of itself, has any assets. The Participant shall have only the rights of a general unsecured creditor of the Company and its Affiliates with respect to amounts credited and benefits payable, if any, with respect to the RSUs, and rights no greater than the right to receive the Common Stock as a general unsecured creditor with respect to RSUs, as and when payable hereunder.

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ARDELYX, INC.

2014 EQUITY INCENTIVE AWARD PLAN

RESTRICTED STOCK AWARD GRANT NOTICE

Ardelyx, Inc., a Delaware corporation, (the “Company”), pursuant to its 2014 Equity Incentive Award Plan, as amended from time to time (the “Plan”), hereby grants to the individual listed below (the “Participant”), in consideration of the mutual agreements set forth herein and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the number of shares of the Company’s Common Stock set forth below (the “Shares”). This Restricted Stock award is subject to all of the terms and conditions as set forth herein and in the Restricted Stock Award Agreement attached hereto as Exhibit A (the “Agreement”) (including without limitation the Restrictions on the Shares set forth in the Agreement) and the Plan, each of which is incorporated herein by reference. Unless otherwise defined herein, the terms defined in the Plan shall have the same defined meanings in this Restricted Stock Award Grant Notice (the “Grant Notice”) and the Agreement.

By his or her signature and the Company’s signature below, the Participant agrees to be bound by the terms and conditions of the Plan, the Agreement and this Grant Notice. The Participant has reviewed the Agreement, the Plan and this Grant Notice in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Grant Notice and fully understands all provisions of this Grant Notice, the Agreement and the Plan. The Participant hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Administrator upon any questions arising under the Plan, this Grant Notice or the Agreement. In addition, by signing below, the Participant also agrees that the Company, in its sole discretion, may satisfy any withholding obligations in accordance with Section 2.2(c) of the Agreement by (i) withholding shares of Common Stock otherwise issuable to the Participant upon vesting of the shares of Restricted Stock, (ii) instructing a broker on the Participant’s behalf to sell shares of Common Stock otherwise issuable to the Participant upon vesting of the shares of Restricted Stock and submit the proceeds of such sale to the Company, or (iii) using any other method permitted by Section 2.2(c) of the Agreement or the Plan. If the participant is married or part of a registered domestic partnership, his or her spouse or domestic partner has signed the Consent of Spouse or Registered Domestic Partner attached to this Grant Notice as Exhibit B.

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EXHIBIT A

TO RESTRICTED STOCK AWARD GRANT NOTICE

RESTRICTED STOCK AWARD AGREEMENT

Pursuant to the Restricted Stock Award Grant Notice (the “Grant Notice”) to which this Restricted Stock Award Agreement (this “Agreement”) is attached, Ardelyx, Inc., a Delaware corporation (the “Company”) has granted to the Participant the number of shares of Restricted Stock (the “Shares”) under the Company’s 2014 Equity Incentive Award Plan, as amended from time to time (the “Plan”), as set forth in the Grant Notice. Capitalized terms not specifically defined herein shall have the meanings specified in the Plan and Grant Notice.

ARTICLE IV.

GENERAL

4.1 Incorporation of Terms of Plan. The Award (as defined below) is subject to the terms and conditions of the Plan, which are incorporated herein by reference. In the event of any inconsistency between the Plan and this Agreement, the terms of the Plan shall control.

ARTICLE V.

AWARD OF RESTRICTED STOCK

5.1 Award of Restricted Stock.

(a) Award. Pursuant to the Grant Notice and upon the terms and conditions set forth in the Plan and this Agreement, effective as of the Grant Date set forth in the Grant Notice, the Company has granted to the Participant an award of Restricted Stock (the “Award”) under the Plan in consideration of the Participant’s past and/or continued employment with or service to the Company or any Affiliate, and for other good and valuable consideration. The number of Shares subject to the Award is set forth in the Grant Notice. The Participant is an Employee, Director or Consultant of the Company or one of its Affiliates.

(b) Book Entry Form; Certificates. At the sole discretion of the Administrator, the Shares will be issued in either (i) uncertificated form, with the Shares recorded in the name of the Participant in the books and records of the Company’s transfer agent with appropriate notations regarding the restrictions on transfer imposed pursuant to this Agreement, and upon vesting and the satisfaction of all conditions set forth in Sections 2.2(b) and (d) hereof, the Company shall remove such notations on any such vested Shares in accordance with Section 2.2(e) below; or (ii) certificated form pursuant to the terms of Sections 2.1(c), (d) and (e) below.

(c) Legend. Certificates representing Shares issued pursuant to this Agreement shall, until all Restrictions (as defined below) imposed pursuant to this Agreement lapse or have been removed and the Shares have thereby become vested or the Shares represented thereby have been forfeited hereunder, bear the following legend (or such other legend as shall be determined by the Administrator):

“THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN VESTING REQUIREMENTS AND MAY BE SUBJECT TO FORFEITURE UNDER THE TERMS OF A RESTRICTED STOCK AWARD AGREEMENT, BY

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AND BETWEEN ARDELYX, INC. AND THE REGISTERED OWNER OF SUCH SHARES, AND SUCH SHARES MAY NOT BE, DIRECTLY OR INDIRECTLY, OFFERED, TRANSFERRED, SOLD, ASSIGNED, PLEDGED, HYPOTHECATED OR OTHERWISE DISPOSED OF UNDER ANY CIRCUMSTANCES, EXCEPT PURSUANT TO THE PROVISIONS OF SUCH AGREEMENT.”

(d) Escrow. The Secretary of the Company or such other escrow holder as the Administrator may appoint may retain physical custody of any certificates representing the Shares until all of the Restrictions on transfer imposed pursuant to this Agreement lapse or shall have been removed; in such event, the Participant shall not retain physical custody of any certificates representing unvested Shares issued to him or her. The Participant, by acceptance of the Award, shall be deemed to appoint, and does so appoint, the Company and each of its authorized representatives as the Participant’s attorney(s)-in-fact to effect any transfer of unvested forfeited Shares (or Shares otherwise reacquired by the Company hereunder) to the Company as may be required pursuant to the Plan or this Agreement and to execute such documents as the Company or such representatives deem necessary or advisable in connection with any such transfer.

(e) Removal of Notations; Delivery of Certificates Upon Vesting. As soon as administratively practicable after the vesting of any Shares subject to the Award pursuant to Section 2.2(b) hereof, the Company shall, as applicable, either remove the notations on any Shares subject to the Award issued in book entry form which have vested or deliver to the Participant a certificate or certificates evidencing the number of Shares subject to the Award which have vested (or, in either case, such lesser number of Shares as may be permitted pursuant to Section 12.2 of the Plan). The Participant (or the beneficiary or personal representative of the Participant in the event of the Participant’s death or incapacity, as the case may be) shall deliver to the Company any representations or other documents or assurances required by the Company. The Shares so delivered shall no longer be subject to the Restrictions hereunder.

5.2 Restrictions.

(a) Forfeiture. Notwithstanding any contrary provision of this Agreement, upon the Participant’s Termination of Service for any or no reason, any portion of the Award (and the Shares subject thereto) which has not vested prior to or in connection with such Termination of Service (after taking into consideration any accelerated vesting and lapsing of Restrictions which may occur in connection with such Termination of Service (if any)) shall thereupon be forfeited immediately and without any further action by the Company, and the Participant’s rights in any Shares and such portion of the Award shall thereupon lapse and expire. For purposes of this Agreement, “Restrictions” shall mean the restrictions on sale or other transfer set forth in Section 3.3 hereof and the exposure to forfeiture set forth in this Section 2.2(a).

(b) Vesting and Lapse of Restrictions. Subject to Section 2.2(a) above, the Award shall vest and Restrictions shall lapse in accordance with the vesting schedule set forth in the Grant Notice (rounding down to the nearest whole Share).

(c) Tax Withholding. The Company or its Affiliates shall be entitled to require a cash payment (or to elect, or permit the Participant to elect, such other form of payment determined in accordance with Section 12.2 of the Plan) by or on behalf of the Participant and/or to deduct from other compensation payable to the Participant any sums required by federal, state or local tax law to be withheld with respect to the grant or vesting of the Award or the lapse of the Restrictions hereunder. In satisfaction of the foregoing requirement with respect to the grant or vesting of the Award or the lapse of the Restrictions hereunder, unless otherwise determined by the Company, the Company or its Affiliates

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shall withhold Shares otherwise issuable under the Award having a fair market value equal to the sums required to be withheld by federal, state and/or local tax law. The number of Shares which shall be so withheld in order to satisfy such federal, state and/or local withholding tax liabilities shall be limited to the number of shares which have a fair market value on the date of withholding equal to the aggregate amount of such liabilities based on the minimum statutory withholding rates for federal, state and/or local tax purposes that are applicable to such supplemental taxable income. Notwithstanding any other provision of this Agreement (including without limitation Section 2.1(b) hereof), the Company shall not be obligated to deliver any new certificate representing Shares to the Participant or the Participant’s legal representative or enter any such Shares in book entry form unless and until the Participant or the Participant’s legal representative, as applicable, shall have paid or otherwise satisfied in full the amount of all federal, state and local taxes applicable to the taxable income of the Participant resulting from the grant or vesting of the Award or the issuance of Shares hereunder.

(d) Conditions to Delivery of Shares. Subject to Section 2.1 above, the Shares deliverable under this Award may be either previously authorized but unissued Shares, treasury Shares or Shares purchased on the open market. Such Shares shall be fully paid and nonassessable. The Company shall not be required to issue or deliver any Shares under this Award prior to fulfillment of the conditions set forth in Section 12.4 of the Plan.

Notwithstanding the foregoing, the issuance of such Shares shall not be delayed if and to the extent that such delay would result in a violation of Section 409A of the Code. In the event that the Company delays the issuance of such Shares because it reasonably determines that the issuance of such Shares will violate Applicable Law, such issuance shall be made at the earliest date at which the Company reasonably determines that issuing such Shares will not cause such violation, as required by Treasury Regulation Section 1.409A-2(b)(7)(ii).

(e) To ensure compliance with the Restrictions, the provisions of the charter documents of the Company, and/or Applicable Law and for other proper purposes, the Company may issue appropriate “stop transfer” and other instructions to its transfer agent with respect to the Restricted Stock. The Company shall notify the transfer agent as and when the Restrictions lapse.

5.3 Consideration to the Company. In consideration of the grant of the Award pursuant hereto, the Participant agrees to render faithful and efficient services to the Company or any Affiliate.

ARTICLE VI.

OTHER PROVISIONS

6.1 Section 83(b) Election. If the Participant makes an election under Section 83(b) of the Code to be taxed with respect to the Restricted Stock as of the date of transfer of the Restricted Stock rather than as of the date or dates upon which the Participant would otherwise be taxable under Section 83(a) of the Code, the Participant hereby agrees to deliver a copy of such election to the Company promptly after filing such election with the Internal Revenue Service.

6.2 Administration. The Administrator shall have the power to interpret the Plan and this Agreement and to adopt such rules for the administration, interpretation and application of the Plan as are consistent therewith and to interpret, amend or revoke any such rules. All actions taken and all interpretations and determinations made by the Administrator in good faith shall be final and binding upon the Participant, the Company and all other interested persons. No member of the Administrator or the Board shall be personally liable for any action, determination or interpretation made in good faith with respect to the Plan, this Agreement or the Award.

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6.3 Restricted Stock Not Transferable. Until the Restrictions hereunder lapse or expire pursuant to this Agreement and the Shares vest, the Restricted Stock (including any Shares received by holders thereof with respect to Restricted Stock as a result of stock dividends, stock splits or any other form of recapitalization) shall be subject to the restrictions on transferability set forth in Section 12.3 of the Plan; provided, however, that this Section 3.3 notwithstanding, with the consent of the Administrator, the Shares may be transferred to one or more Permitted Transferees, subject to and in accordance with Section 12.3 of the Plan.

6.4 Rights as Stockholder. Except as otherwise provided herein, upon the Grant Date, the Participant shall have all the rights of a stockholder of the Company with respect to the Shares, subject to the Restrictions, including, without limitation, voting rights and rights to receive any cash or stock dividends, in respect of the Shares subject to the Award and deliverable hereunder.

6.5 Tax Consultation. The Participant understands that the Participant may suffer adverse tax consequences in connection with the Restricted Stock granted pursuant to this Agreement (and the Shares issuable with respect thereto). The Participant represents that the Participant has consulted with any tax consultants the Participant deems advisable in connection with the Restricted Stock and that the Participant is not relying on the Company for any tax advice.

6.6 Adjustments Upon Specified Events. The Administrator may accelerate the vesting of the Restricted Stock in such circumstances as it, in its sole discretion, may determine. The Participant acknowledges that the Restricted Stock is subject to adjustment, modification and termination in certain events as provided in this Agreement and Section 14.2 of the Plan.

6.7 Notices. Any notice to be given under the terms of this Agreement to the Company shall be addressed to the Company in care of the Secretary of the Company at the Company’s principal office, and any notice to be given to the Participant shall be addressed to the Participant at the Participant’s last address reflected on the Company’s records. By a notice given pursuant to this Section 3.7, either party may hereafter designate a different address for notices to be given to that party. Any notice shall be deemed duly given when sent via email or when sent by certified mail (return receipt requested) and deposited (with postage prepaid) in a post office or branch post office regularly maintained by the United States Postal Service.

6.8 Participant’s Representations. If the Shares issuable hereunder have not been registered under the Securities Act or any applicable state laws on an effective registration statement at the time of such issuance, the Participant shall, if required by the Company, concurrently with such issuance, make such written representations as are deemed necessary or appropriate by the Company and/or its counsel.

6.9 Titles. Titles are provided herein for convenience only and are not to serve as a basis for interpretation or construction of this Agreement.

6.10 Governing Law. The laws of the State of Delaware shall govern the interpretation, validity, administration, enforcement and performance of the terms of this Agreement regardless of the law that might be applied under principles of conflicts of laws.

6.11 Conformity to Securities Laws. The Participant acknowledges that the Plan and this Agreement are intended to conform to the extent necessary with all provisions of the Securities Act and the Exchange Act, and any and all Applicable Law. Notwithstanding anything herein to the contrary, the Plan shall be administered, and the Award is granted, only in such a manner as to conform to such Applicable Law. To the extent permitted by Applicable Law, the Plan and this Agreement shall be deemed amended to the extent necessary to conform to such Applicable Law.

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6.12 Amendment, Suspension and Termination. To the extent permitted by the Plan, this Agreement may be wholly or partially amended or otherwise modified, suspended or terminated at any time or from time to time by the Administrator or the Board; provided, however, that, except as may otherwise be provided by the Plan, no amendment, modification, suspension or termination of this Agreement shall adversely affect the Award in any material way without the prior written consent of the Participant.

6.13 Successors and Assigns. The Company or any Affiliate may assign any of its rights under this Agreement to single or multiple assignees, and this Agreement shall inure to the benefit of the successors and assigns of the Company and its Affiliates. Subject to the restrictions on transfer set forth in Section 3.3 hereof, this Agreement shall be binding upon the Participant and his or her heirs, executors, administrators, successors and assigns.

6.14 Limitations Applicable to Section 16 Persons. Notwithstanding any other provision of the Plan or this Agreement, if the Participant is subject to Section 16 of the Exchange Act, then the Plan, the Award and this Agreement shall be subject to any additional limitations set forth in any applicable exemptive rule under Section 16 of the Exchange Act (including any amendment to Rule 16b-3 of the Exchange Act) that are requirements for the application of such exemptive rule. To the extent permitted by applicable law, this Agreement shall be deemed amended to the extent necessary to conform to such applicable exemptive rule.

6.15 Not a Contract of Service Relationship. Nothing in this Agreement or in the Plan shall confer upon the Participant any right to continue to serve as an Employee or other service provider of the Company or any of its Affiliates or shall interfere with or restrict in any way the rights of the Company and its Affiliates, which rights are hereby expressly reserved, to discharge or terminate the services of the Participant at any time for any reason whatsoever, with or without cause, except to the extent expressly provided otherwise in a written agreement between the Company or an Affiliate and the Participant.

6.16 Entire Agreement. The Plan, the Grant Notice and this Agreement (including all Exhibits thereto, if any) constitute the entire agreement of the parties and supersede in their entirety all prior undertakings and agreements of the Company and its Affiliates and the Participant with respect to the subject matter hereof.

6.17 Limitation on the Participant’s Rights. Participation in the Plan confers no rights or interests other than as herein provided. This Agreement creates only a contractual obligation on the part of the Company as to amounts payable and shall not be construed as creating a trust. Neither the Plan nor any underlying program, in and of itself, has any assets. The Participant shall have only the rights of a general unsecured creditor of the Company and its Affiliates with respect to amounts credited and benefits payable, if any, with respect to the Shares issuable hereunder.

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EXHIBIT B

TO RESTRICTED STOCK AWARD GRANT NOTICE

CONSENT OF SPOUSE OR REGISTERED DOMESTIC PARTNER

I,                         , spouse or domestic partner of                         , have read and approve the Restricted Stock Award Grant Notice (the “Grant Notice”) to which this Consent of Spouse or Registered Domestic Partner is attached and the Restricted Stock Award Agreement (the “Agreement”) attached to the Grant Notice. In consideration of issuing to my spouse or domestic partner the shares of the common stock of Ardelyx, Inc. set forth in the Grant Notice, I hereby appoint my spouse or domestic partner as my attorney-in-fact in respect to the exercise of any rights under the Agreement and agree to be bound by the provisions of the Agreement insofar as I may have any rights in said Agreement or any shares of the common stock of Ardelyx, Inc. issued pursuant thereto under the community property laws or similar laws relating to marital property in effect in the state of our residence as of the date of the signing of the foregoing Agreement.

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