Cooney Paula M. 4

What Happened Paula M. Cooney, Senior Vice President and Chief Human Resources Officer at Trinseo PLC, had a total of 10,124 shares withheld by the company to cover tax withholding following the vesting of restricted stock units (RSUs). The filing reports 7,440 shares withheld on 2026-02-21 at $0.33 per share (reported value $2,437) and 2,684 shares withheld on 2026-02-22 at $0.33 per share (reported value $879), for a combined reported value of $3,316. This is a routine tax-withholding disposition (not an open-market sale indicating a trading decision).

Key Details

• Transaction dates and amounts:
  • 2026-02-21: 7,440 shares withheld @ $0.33 — reported $2,437 (code F)
  • 2026-02-22: 2,684 shares withheld @ $0.33 — reported $879 (code F)
• Total shares withheld: 10,124; total reported value: $3,316.
• Transaction code: F (shares withheld by the company to pay taxes due following RSU vesting) — see footnote F1.
• Shares owned after the transaction: not disclosed in this Form 4 filing.
• Filing date: 2026-02-24; based on transaction dates (Feb 21–22) this appears to be filed within the normal Form 4 reporting window (not marked late).

Context Shares withheld to cover taxes after RSU vesting are a routine administrative disposition (cashless or share-surrender withholding) and generally do not signal insider sentiment like an open-market sale or purchase would. The filing simply reflects the tax payment mechanism for vested awards.