Trinseo PLC (TSEO)

Trinseo PLC is a specialty materials company incorporated in Ireland and operated from Berwyn, Pennsylvania. It was created in 2010 when Bain Capital acquired a group of styrenics, latex and plastics businesses from The Dow Chemical Company. The business was originally known as Styron before taking the Trinseo name.

The company produced materials such as polystyrene, acrylics, synthetic rubber, latex binders and engineered plastics. These went into automotive parts, building and construction products, packaging, consumer goods, paper coatings and carpet backing. Trinseo operated plants in North America, Europe and Asia, and a large share of its sales were outside the United States.

Trinseo completed its initial public offering in June 2014 and its ordinary shares traded on the New York Stock Exchange under the symbol TSE. In later years it carried out strategic transactions, including the acquisition of Arkema's PMMA business in 2021 and the sale of several businesses.

Its results were affected by weak demand in Europe and in construction and automotive markets, volatile feedstock costs, and excess capacity in several product lines. These pressures, together with a heavy debt load of roughly $2 billion, strained liquidity and led it to consider restructuring alternatives.

The NYSE filed a Form 25 on March 23, 2026, and the delisting became effective on March 30, 2026. The ordinary shares began trading over the counter under the symbol TSEOF.

In an 8-K dated May 13, 2026, Trinseo disclosed a restructuring support agreement under which it planned to commence Chapter 11 cases in the U.S. Bankruptcy Court for the Southern District of Texas by May 25, 2026. The plan would discharge about $2.0 billion of funded debt, give existing lenders initially 100 percent of the reorganized equity, cancel existing equity interests without recovery, and leave trade creditors unimpaired. It provided for debtor-in-possession financing of $427.5 million and a $450 million backstopped equity rights offering.

An equity cancellation in a Chapter 11 plan means that existing shareholders generally receive no distribution, and the over-the-counter symbol, which ends in F for a foreign issuer, reflects the company's Irish incorporation. The company also noted that completion of the plan depended on court approval, regulatory clearances and Irish law steps, so the outcome was not assured when the agreement was announced.