Definitive Additional Materials





Washington, D.C. 20549




Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.     )



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¨   Definitive Proxy Statement
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Ardelyx, Inc.

(Name of Registrant as Specified In Its Charter)


(Name of Person(s) Filing Proxy Statement, if Other Than The Registrant)

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Important Notice of Availability of Proxy Materials for the Stockholder Meeting of


To Be Held On: June 2, 2016 at 8:30 am local time at

34175 Ardenwood Blvd., Suite 200, Fremont, California 94555




This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. We encourage you to access and review all of the important information contained in the proxy materials before voting.

If you want to receive a paper or e-mail copy of the proxy materials you must request one. There is no charge to you for requesting a copy. To facilitate timely delivery please make the request as instructed below before May 20, 2016.

Please visit, where the following materials are available for view:

• Notice of Annual Meeting of Stockholders

• Proxy Statement

• Form of Electronic Proxy Card

• Annual Report on Form 10-K


TELEPHONE: 888-Proxy-NA (888-776-9962) 718-921-8562 (for international callers)




ONLINE: To access your online proxy card, please visit and follow the on-screen instructions or scan the QR code with your smartphone. You may enter your voting instructions at up until 11:59 PM Eastern Time the day before the cut-off or meeting date.

IN PERSON: You may vote your shares in person by attending the Annual Meeting.

TELEPHONE: To vote by telephone, please visit to view the materials and to obtain the toll free number to call.

MAIL: You may request a card by following the instructions above.

1. To elect two Class 2 directors to hold office until the 2019 Annual Meeting of Stockholders and until their successors are elected and qualified.


David Mott

Michael Raab

2. To ratify the selection, by the Audit Committee of our Board of Directors, of Ernst

& Young, LLP as the independent registered public accounting firm of the Company for the fiscal year ended December 31, 2016.

3. To transact any other business as may properly be presented at the Annual Meeting or any adjournment or postponement thereof These items of business are more fully described in the proxy statement. The record date for the Annual Meeting is April 8, 2016. Only stockholders of record at the close of business on that date may vote at the meeting or any adjournment thereof.

Please note that you cannot use this notice to vote by mail.