Thurman Alex R. 4

What Happened
Alex R. Thurman, Chief Financial Officer of Glaukos Corp (GKOS), disposed of a total of 1,239 shares in mid‑March 2026 for aggregate proceeds of $122,718. Transactions reported: 614 shares were withheld by the issuer to satisfy tax withholding on vested restricted stock units (3/16/2026) valued at $98.94/share ($60,749), and 625 shares were sold in an open‑market sale (3/17/2026) at $99.15/share ($61,969). Both actions are dispositions (sales/routine tax withholding), not purchases.

Key Details

• Transactions:
  • 2026-03-16 — 614 shares withheld (Code F) at $98.94/share — $60,749 (tax withholding on RSU vesting).
  • 2026-03-17 — 625 shares sold (Code S) in open market at $99.15/share — $61,969.
• Total disposed: 1,239 shares for $122,718.
• Shares owned after transaction: not specified in the provided excerpt; footnote notes the Reporting Person holds 12,512 restricted stock units that have not yet vested and 167 shares from the Employee Stock Purchase Plan (F2).
• Footnotes of note:
  • F1: 614 shares withheld to cover tax withholding upon vesting of RSUs granted March 14, 2024.
  • F3: The open‑market sale was effected under a Rule 10b5‑1 trading plan adopted December 15, 2025.
• Filing timeliness: The Form 4 was filed March 19, 2026. The 3/17 sale was reported within the two‑business‑day window; the 3/16 tax‑withholding disposition appears to have been reported one business day late.

Context
Tax‑withholding dispositions (Code F) occur when the company retains shares to cover tax obligations on vested awards and do not reflect a market sale decision. The 625‑share sale was executed under a prearranged 10b5‑1 plan, which typically schedules trades in advance. These transactions are routine insider dispositions; they are factual disclosures and do not, by themselves, indicate management’s view of the company’s prospects.