FilingIndex
SC 13DThe Stakes

Koppers Holdings Inc. files SC 13D

Filed May 19, 2026 · 1mo ago · Accession 0000921895-26-001441

Plain English

Activist stake — an investor has acquired more than 5% with intent to influence.

Read the source below for the full document.

Filing details
Ticker
KOP
CIK
1315257
Form type
SC 13D
Filing date
May 19, 2026
Report date
Document
Size