X0508 4 2026-02-03 0 0001708035 Ecovyst Inc. ECVT 0001795151 Ward Susan F C/O ECOVYST INC. 600 LEE ROAD, SUITE 200 WAYNE PA 19087 1 0 0 0 0 Common Stock 2026-02-03 4 A 0 19399 0 A 97660 D /s/ Joseph S. Koscinski, as attorney-in-fact for Susan F. Ward 2026-02-05