Cooney Paula M. 4

What Happened
Paula M. Cooney, Senior Vice President and Chief Human Resources Officer of Trinseo PLC, had 7,670 shares withheld on 2026-02-27 to satisfy tax obligations following the vesting of restricted stock units. The filing reports the shares at $0.23 per share for a total of $1,764. This is a tax-withholding disposition (not an open-market sale or purchase).

Key Details

• Transaction date: 2026-02-27; reported on Form 4 filed 2026-03-03 (within the two-business-day filing window).
• Shares withheld/disposed: 7,670 at $0.23 per share; total value shown $1,764.
• Reporting code: F (shares withheld to cover tax liability).
• Footnote: F1 — shares withheld by the company to pay taxes due following RSU vesting.
• Shares owned after the transaction: not specified in the filing.

Context
Tax-withholding by an employer after restricted stock unit vesting is routine and typically reported as a disposition for tax purposes; it does not indicate an independent decision to sell shares on the market.