UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a)

of the Securities Exchange Act of 1934

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

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☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☐ Definitive Proxy Statement

☒ Definitive Additional Materials

☐ Soliciting Material Pursuant to §240.14a-12

REATA PHARMACEUTICALS, INC.

(Name of Registrant as Specified In Its Charter)

N/A

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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US 4951857v.2

RETA PHARMACEUTICALS Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to be held on June 12, 2019, for Reata Pharmaceuticals, Inc. This is not a ballot. You cannot use this notice to vote your shares. 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. To view the proxy statement and annual report, go to www.proxydocs.com/RETA. To submit your proxy while visiting this site, you will need the 12 digit control number in the box below. Under United States Securities and Exchange Commission rules, proxy materials do not have to be delivered in paper. Proxy materials can be distributed by making them available on the Internet. We have chosen to use these procedures for our 2019 Annual Meeting and need YOUR participation. 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. In order to receive a paper package in time for this year’s annual meeting, please make this request on or before June 3, 2019. For a Convenient Way to VIEW Proxy Materials _ and _ VOTE Online go to: www.proxydocs.com/RETA Proxy Materials Available to View or Receive: 1. Proxy Statement and Notice of Annual Meeting 2. 2018 Annual Report Printed materials may be requested by one of the following methods: INTERNET www.investorelections.com/RETA TELEPHONE (866) 648-8133 *E-MAIL paper@investorelections.com * If requesting material by e-mail, please send You must use the 12 digit control number a blank e-mail with the 12 digit control number (located below) in the subject line. No other located in the shaded gray box below. requests, instructions or other inquiries should be included with your e-mail requesting material. ACCOUNT NO. SHARES Reata Pharmaceuticals, Inc. Notice of Annual Meeting Date: Wednesday, June 12, 2019 Time: 08:00 A.M. (Central Daylight Time) Place: 5320 Legacy Drive, Plano, TX 75024 For holders as of: April 18, 2019 The Board of Directors recommends that you vote “FOR” Proposals 1, 2 and 3. 1. Election of Class I Directors 01 J. Warren Huff 02 Jack B. Nielsen 2. To approve the Second Amended and Restated Long Term Incentive Plan. 3. To ratify the appointment of Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2019. 4. The transaction of such other business as may properly come before the meeting or at any and all adjournments or postponements thereof. NOTE: To obtain directions to attend the meeting and vote in person, please contact us at (469) 442-4772.