KOP - Koppers Holdings Inc (KOP) Q1 2021 Earnings Call Transcript May, 07 2021 11:30 PM Koppers Holdings Inc. Image source: The Motley Fool. Koppers Holdings Inc (NYSE: KOP) Q1 2021 Earnings Call May 7, 2021 , 11:00 a.m. ET Operator Continue reading For further details see: Koppers Holdings Inc (KOP) Q1 2021 Earnings Call Transcript