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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☐	Soliciting Material Under §240.14a-12
GLAUKOS CORPORATION
(Name of Registrant as Specified In Its Charter)
	Not applicable
	(Name of Person(s) Filing Proxy Statement, if other than the Registrant)
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*** Exercise Your Right to Vote *** Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to Be Held on June 3, 2020. GLAUKOS CORPORATION GLAUKOS CORPORATION 229 AVENIDA FABRICANTE SAN CLEMENTE, CA 92672 You are receiving this communication because you hold shares in the company named above. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting. proxy materials and voting instructions. D11611-P37624 See the reverse side of this notice to obtain Meeting Information Meeting Type: Annual Meeting For holders as of: April 8, 2020 Date: June 3, 2020 Time: 9:00 AM, Pacific Time Location: Meeting live via the Internet-please visit www.virtualshareholdermeeting.com/GKOS2020. The company will be hosting the meeting live via the Internet this year. To attend the meeting via the Internet please visit www.virtualshareholdermeeting.com/GKOS2020 and be sure to have the information that is printed in the box marked by the arrow (located on the following page). XXXX XXXX XXXX XXXX

Before You Vote How to Access the Proxy Materials How To Vote Please Choose One of the Following Voting Methods D11612-P37624 Vote By Internet: Before The Meeting: Go to www.proxyvote.com. Have the information that is printed in the box marked by the arrow (located on the following page) available and follow the instructions. During The Meeting: Go to www.virtualshareholdermeeting.com/GKOS2020. Have the information that is printed in the box marked by the arrow (located on the following page) available and follow the instructions. Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card. XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX Proxy Materials Available to VIEW or RECEIVE: NOTICE AND PROXY STATEMENT2019 ANNUAL REPORT ON FORM 10-K How to View Online: Have the information that is printed in the box marked by the arrow (located on the following page) and visit: www.proxyvote.com. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request: 1) BY INTERNET: www.proxyvote.com 2) BY TELEPHONE: 1-800-579-1639 3) BY E-MAIL*: sendmaterial@proxyvote.com * If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked by the arrow (located on the following page) in the subject line. Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before May 20, 2020 to facilitate timely delivery. XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX

The Board of Directors recommends you vote FOR ALL the following: 1. Election of Directors Nominees: 01) William J. Link, Ph.D. 02) Aimee S. Weisner The Board of Directors recommends you vote FOR proposal 2: 2. Approval, on an advisory basis, of the compensation of the Company's named executive officers. The Board of Directors recommends you vote FOR proposal 3: 3. Ratification of the appointment of Ernst & Young LLP as the Company’s independent registered public accounting firm for the year ending December 31, 2020. 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. D11613-P37624 Voting Items

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