Trinseo PLC (TSE) Institutional Ownership

Ownership Summary

Trinseo PLC (NYSE:TSE) showed up in the 13F filings of 71 institutional investors as of December 2025.

• Collectively, these holders controlled 68.6% of Trinseo's outstanding shares in December 2025, down from 78.4% in September 2025.
• They decreased total shares held in TSE by -7.75% quarter over quarter, and investors in Trinseo decreased 26.04% from a year ago.
• During the quarter, 26 of these 71 funds increased positions in TSE, 24 reduced exposure, and 21 held steady.
• Combined, these investors held 24.71Mn shares in TSE for December 2025, down by 2.08Mn shares quarter on quarter, and down 730.59K shares year over year.
• M&G Plc is the top holder of Trinseo as of December 31, 2025, with 7.63Mn shares representing 21.18% of outstanding stock.
• Leading buyers of Trinseo shares for the quarter ending December 2025 were CHARLES SCHWAB INVESTMENT MANAGEMENT INC (586.06K), GSA CAPITAL PARTNERS LLP (511.34K), Goldman Sachs Group Inc (454.63K), DEUTSCHE BANK AG\ (96.82K), Morgan Stanley (82.14K).
• Leading sellers of Trinseo shares for the quarter ending December 2025 were CastleKnight Management LP (1.95Mn), ICON ADVISERS INC/CO (1.0Mn), Bank Of America Corp /De/ (687.48K), Royal Bank Of Canada (225.36K), Invesco Ltd. (61.48K).
• According to Business Quant data, leading holders of TSE for December 2025 are M&G Plc (7.63Mn), Nut Tree Capital Management, LP (3.5Mn), BlackRock, Inc. (2.41Mn), CHARLES SCHWAB INVESTMENT MANAGEMENT INC (2.09Mn), Owl Creek Asset Management, L.P. (1.67Mn), ICON ADVISERS INC/CO (1.0Mn), GEODE CAPITAL MANAGEMENT, LLC (841.72K), VANGUARD GROUP INC (762.83K), Goldman Sachs Group Inc (580.62K), Morgan Stanley (536.42K).