Koppers Holdings Inc. — SCHEDULE 13G/A Filings
5 SCHEDULE 13G/A filings on record
This page lists all SCHEDULE 13G/A filings submitted to the SEC by Koppers Holdings Inc. (KOP), sorted by most recent first. Each row links to the full filing on EdgarLookup. Koppers Holdings Inc. has filed 5 SCHEDULE 13G/A documents with the SEC since 2015. To view all SEC filings by Koppers Holdings Inc., see the full filings list.
All
10-K
10-K/A
10-Q
144
144/A
3
3/A
4
4/A
424B1
424B3
5
5/A
8-A12B
8-K
8-K/A
ARS
CERTNYS
CORRESP
DEF 14A
DEFA14A
EFFECT
POS AM
POSASR
PRE 14A
S-1
S-1/A
S-3
S-3/A
S-3ASR
S-4
S-4/A
S-8
SC 13G
SC 13G/A
SCHEDULE 13G
SCHEDULE 13G/A
UPLOAD
| Form | Description | Accession Number | Filed | Period |
|---|---|---|---|---|
| SCHEDULE 13G/A | — | 0000102909-26-001632 | Mar 27, 2026 | — |
| SCHEDULE 13G/A | — | 0000102909-25-000256 | Oct 31, 2025 | — |
| SCHEDULE 13G/A | — | 0000932471-25-000643 | Apr 30, 2025 | — |
| SCHEDULE 13G/A | — | 0002052113-25-001508 | Apr 23, 2025 | — |
| SCHEDULE 13G/A | — | 0002012383-25-001483 | Feb 5, 2025 | — |