X0306 4 2019-02-19 0 0001192448 GLAUKOS Corp GKOS 0001705850 Gilliam Joseph E C/O GLAUKOS CORPORATION, 229 AVENIDA FABRICANTE SAN CLEMENTE CA 92672 0 1 0 0 CFO, SVP Corporate Development Common Stock 2019-02-19 4 S 0 5000 70.03 D 75694 D These trades were made pursuant to a Rule 10b5-1 trading plan with pre-determined share amounts and prices. This transaction was executed in multiple trades at prices ranging from $70.00 to $70.195. The price reported above reflects the weighted average price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. The reported amount reflects (1) a transfer of 6,758 shares of Glaukos common stock made by the reporting person pursuant to a domestic relations order exempt from reporting pursuant to Section 16a-12 under the U.S. Securities Exchange Act of 1934, as amended, and (2) 1,335 shares acquired by the reporting person pursuant to the stockholder-approved Glaukos 2015 Employee Stock Purchase Plan. /s/ Robert L. Davis, Attorney-in-Fact 2019-02-21