Ecovyst Inc. — Form 8-K

Ecovyst Catalyst Technologies LLC adopted a Second Amended and Restated Severance Plan effective October 22, 2026, enhancing severance benefits for eligible employees. Key changes include: (1) Executive officers now receive 52 weeks of base compensation plus target bonus (CEO receives 104 weeks); (2) non-executives receive 2 weeks per year of service (minimum 4-52 weeks depending on grade); (3) change-in-control severance increased to 18 months for executives other than CEO and 30 months for CEO; (4) enhanced post-employment obligations including non-compete and confidentiality agreements required as condition of payment. The plan applies to Ecovyst Inc. and wholly-owned subsidiaries; no dollar amounts or share counts are specified in the filing.