0001708035-26-000036.txt : 20260205 0001708035-26-000036.hdr.sgml : 20260205 20260205160457 ACCESSION NUMBER: 0001708035-26-000036 CONFORMED SUBMISSION TYPE: 4 PUBLIC DOCUMENT COUNT: 1 CONFORMED PERIOD OF REPORT: 20260203 FILED AS OF DATE: 20260205 DATE AS OF CHANGE: 20260205 REPORTING-OWNER: OWNER DATA: COMPANY CONFORMED NAME: Koscinski Joseph S. CENTRAL INDEX KEY: 0001717992 ORGANIZATION NAME: FILING VALUES: FORM TYPE: 4 SEC ACT: 1934 Act SEC FILE NUMBER: 001-38221 FILM NUMBER: 26602837 MAIL ADDRESS: STREET 1: C/O PQ GROUP HOLDINGS INC. STREET 2: 300 LINDENWOOD DRIVE CITY: MALVERN STATE: PA ZIP: 19355 ISSUER: COMPANY DATA: COMPANY CONFORMED NAME: Ecovyst Inc. CENTRAL INDEX KEY: 0001708035 STANDARD INDUSTRIAL CLASSIFICATION: CHEMICALS & ALLIED PRODUCTS [2800] ORGANIZATION NAME: 08 Industrial Applications and Services EIN: 813406833 STATE OF INCORPORATION: DE FISCAL YEAR END: 1231 BUSINESS ADDRESS: STREET 1: 600 LEE ROAD, SUITE 200 CITY: WAYNE STATE: PA ZIP: 19087 BUSINESS PHONE: 484-617-1200 MAIL ADDRESS: STREET 1: 600 LEE ROAD, SUITE 200 CITY: WAYNE STATE: PA ZIP: 19087 FORMER COMPANY: FORMER CONFORMED NAME: PQ Group Holdings Inc. DATE OF NAME CHANGE: 20170531 4 1 wk-form4_1770325495.xml FORM 4 X0508 4 2026-02-03 0 0001708035 Ecovyst Inc. ECVT 0001717992 Koscinski Joseph S. C/O ECOVYST INC. 600 LEE ROAD, SUITE 200 WAYNE PA 19087 0 1 0 0 See Remarks 0 Common Stock 2026-02-03 4 A 0 27158 0 A 584732 D Vice President, Chief Administrative Officer, General Counsel and Secretary /s/ Joseph S. Koscinski 2026-02-05