Koppers Holdings(KOP) - 2025 Q3 - Quarterly Results

Koppers Holdings Inc. 436 Seventh Avenue Pittsburgh, PA 15219-1800 Tel 412 227 2001 www.koppers.com KOPPERS REPORTS THIRD QUARTER 2025 RESULTS Exhibit 99.1 News Release FOR IMMEDIATE RELEASE For Information: Quynh McGuire Vice President, Investor Relations 412 227 2049 McGuireQT@koppers.com PITTSBURGH, November 7, 2025 – Koppers Holdings Inc. (NYSE: KOP), an integrated global provider of treated wood products, wood treatment chemicals, and carbon compounds, today reported its third quarter of 2025 results. ...