Additional Proxy Soliciting Materials (Form DEFA14A)

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 ☐

Check the appropriate box:

Your Vote Counts! GLAUKOS CORPORATION 2026 Annual Meeting Vote by May 27, 2026 11:59 PM ET GLAUKOS CORPORATION ONE GLAUKOS WAY ALISO VIEJO, CA 92656 You invested in GLAUKOS CORPORATION and it's time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy material for the stockholder meeting to be held on May 28, 2026. Get informed before you vote View the Notice & Proxy Statement, Annual Report online OR you can receive a free paper or email copy of the material(s) by requesting prior to May 14, 2026. If you would like to request a copy of the material(s) for this and/or future stockholder meetings, you may (1) visit www.ProxyVote.com, (2) call 1-800-579-1639 or (3) send an email to [email protected]. If sending an email, please include your control number (indicated below) in the subject line. Unless requested, you will not otherwise receive a paper or email copy. Smartphone users Point your camera here and vote without entering a I number Virtually at: Vote Virtually at the Meeting* May 28, 2026 9:00 AM PDT www.virtualshareholdermeeting.com/GKOS2026 *Please check the meeting materials for any special requirements for meeting attendance.

Vote at www.ProxyVote.com THIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming stockholder meeting. Please follow the instructions on the reverse side to vote these important matters. Voting Items 1. Election of Directors Nominees:01) Denice M. Torres 02) Aimee S. WeisnerBoard Recommends 2.Approval, on an advisory basis, of the compensation of the Company's named executive officers. 3.Ratification of the appointment of Ernst & Young LLP as the Company's independent registered public accounting firm for the year ending December 31, 2026. For For NOTE: In their discretion, the proxies are authorized to vote upon such other business as may properly come before the meeting and any adjournment or postponement thereof. Prefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click "Delivery Settings".