Buesinger Robert F. 4

What Happened

• Robert F. Buesinger, EVP and PEM Segment Head at Westlake Corp (WLK), had 3,478 restricted stock units (RSUs) vest on Feb 17, 2026. The RSUs converted one‑for‑one into 3,478 common shares (reported as derivative exercise/conversion).
• To satisfy tax withholding obligations, 903 of those shares were withheld on Feb 18 at $98.95 per share, totaling $89,352. Net shares issued to Buesinger = 3,478 - 903 = 2,575 shares, worth roughly $254,800 using the $98.95/share withholding price.
• This was not an open‑market purchase or sale by the insider; it was a routine vesting and tax‑withholding event.

Key Details

• Transaction dates/prices: RSU conversion on 2026-02-17 (3,478 RSUs → 3,478 shares); tax withholding on 2026-02-18, 903 shares withheld at $98.95 each ($89,352).
• Transaction codes: M = exercise/conversion of derivative (RSU conversion); F = shares withheld to pay tax obligations.
• Footnotes: RSUs convert one‑for‑one; grant was made 2023-02-17 with a 3‑year vesting; shares were withheld to satisfy tax liabilities (standard practice).
• Shares owned after transaction: not specified in the provided filing.
• Filing date: Form 4 filed 2026-02-19 for a 2026-02-17 vesting — appears timely (no late filing indicated).

Context

• This is a routine RSU vesting and tax-withholding event (not a market sale). Withheld shares are commonly used by companies to cover taxes and do not necessarily indicate insider sentiment.
• The filing shows a derivative conversion (RSUs to stock) and withholding rather than a cash purchase or open‑market disposition.