SEC Form DEFA14A filed by Clearside Biomedical Inc.

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

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Clearside Biomedical, Inc.

(Name of Registrant as Specified In Its Charter)

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P.O. BOX 8016, CARY, NC 27512-9903 Your vote matters! Clearside Biomedical, Inc. Annual Meeting of Stockholders Friday, May 30, 2025 8:00 AM, Eastern Time 900 North Point Parkway, Suite 200, Alpharetta, GA 30005 styleINA Meeting Materials: Notice of Meeting and Proxy Statement & Annual Report or Form 10-K Important Notice Regarding the Availability of Proxy Materials for the Stockholders Meeting to be Held on May 30, 2025 for Stockholders of Record as of April 1, 2025 To order materials for this and/or future stockholder meetings, use one of the following methods. For a convenient way to view proxy materials, VOTE, and obtain directions to attend the meeting go to www.proxydocs.com/CLSD To vote your proxy while visiting this site, you will need the 12 digit control number in the box below. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. This is not a ballot. You cannot use this notice to vote your shares. We encourage you to access and review all of the important information contained in the proxy materials before voting. 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. If you want to receive a paper or e-mail copy of the proxy material, 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 meeting, you must make this request on or before May 20, 2025. Internet: www.investorelections.com/CLSD Call: 1-866-648-8133 Email: [email protected] * If requesting material by e-mail, please send a blank e-mail with the 12 digit control number (located below) in the subject line. No other requests, instructions OR other inquiries should be included with your e-mail requesting material. Your control number Have the 12 digit control number located in the box above available when you access the website and follow the instructions. SEE REVERSE FOR FULL AGENDA Copyright © 2025 BetaNXT, Inc. or its affiliates. All Rights Reserved

Clearside Biomedical, Inc. Annual Meeting of Stockholders THE BOARD OF DIRECTORS RECOMMENDS A VOTE: FOR ON PROPOSALS 1, 2, 3 AND 4 PROPOSAL 1. Election of Directors 1.01 Anthony S. Gibney 1.02 George Lasezkay 1.03 Christy L. Shaffer 2. Approval, on an advisory basis, of the compensation of the Company's named executive officers, as disclosed in the proxy statement. 3. Ratification of the selection of Ernst & Young LLP as the Company's independent registered public accounting firm for the fiscal year ending December 31, 2025. 4. Approval of an amendment to the Company's Amended and Restated Certificate of Incorporation to increase the authorized number of shares of common stock from 200,000,000 shares to 400,000,000 shares. NOTE: In their discretion, the proxies are authorized to vote upon such other business as may properly come before the meeting, including any adjournment or postponement thereof.