Trinseo (TSE) Proxy Filing summary

Executive summary

• Annual General Meeting scheduled for June 25, 2025, with voting open until June 23, 2025.

• Shareholders can access proxy materials online or request paper/email copies by June 11, 2025.

• Meeting will be held in Dublin, Ireland, with in-person and online voting options.

Voting matters and shareholder proposals

• Election of nine directors, each for a one-year term expiring at the 2026 Annual General Meeting.

• Advisory vote to approve executive compensation for named executive officers.

• Ratification of PricewaterhouseCoopers LLP as independent auditor for 2025 and authorization for the Audit Committee to set remuneration.

• Proposal to grant the Board authority to issue shares under Irish law.

• Proposal to allow the Board to opt out of statutory pre-emption rights for up to 10% of issued share capital.

• Setting the price range for re-issuance of treasury shares.

• Amendments to the 2014 Omnibus Incentive Plan.

• Allowing CEO, CFO, and CLO to voluntarily forfeit stock options for no consideration, returning them to the equity plan.

Board of directors and corporate governance

• Nine director nominees listed for election, each to serve a one-year term.