Financial reports
ARS
2023 FY
Annual report to shareholders
2 Apr 24
10-K
2023 FY
Annual report
28 Feb 24
10-Q
2023 Q3
Quarterly report
3 Nov 23
10-Q
2023 Q2
Quarterly report
3 Aug 23
10-Q
2023 Q1
Quarterly report
5 May 23
ARS
2022 FY
Annual report to shareholders
3 Apr 23
10-K
2022 FY
Annual report
27 Feb 23
10-Q
2022 Q3
Quarterly report
4 Nov 22
10-Q
2022 Q2
Quarterly report
4 Aug 22
10-Q
2022 Q1
Quarterly report
6 May 22
Current reports
8-K
Entry into a Material Definitive Agreement
15 Apr 24
8-K
Koppers Reports Fourth Quarter and Full-Year 2023 Results; Provides 2024 Outlook
28 Feb 24
8-K
Koppers Holdings Names Nishan J. Vartanian to Board
13 Feb 24
8-K
Koppers Names James A. Sullivan President and Chief Operating Officer
2 Jan 24
8-K
Koppers Reports Third Quarter 2023 Results; Reaffirms 2023 Outlook
3 Nov 23
8-K
Koppers Announces Successful Completion of Term Loan B Repricing
12 Oct 23
8-K
Koppers Holdings Inc. Announces Increase to 2023 Outlook
14 Sep 23
8-K
Amendments to Articles of Incorporation or Bylaws
3 Aug 23
8-K
Koppers Reports Second Quarter 2023 Results; Reaffirms 2023 Outlook
3 Aug 23
8-K
Koppers Reports First Quarter 2023 Results; Reaffirms 2023 Outlook
5 May 23
Registration and prospectus
S-8
Registration of securities for employees
6 Aug 21
S-8
Registration of securities for employees
7 May 21
S-8
Registration of securities for employees
7 May 21
S-8
Registration of securities for employees
6 May 20
424B3
Prospectus supplement
27 Feb 20
S-3ASR
Automatic shelf registration
27 Feb 20
S-8
Registration of securities for employees
3 May 18
S-8
Registration of securities for employees
3 Aug 17
S-3ASR
Automatic shelf registration
15 Dec 16
S-8
Registration of securities for employees
10 Jun 16
Proxies
DEF 14A
Definitive proxy
2 Apr 24
PRE 14A
Preliminary proxy
8 Mar 24
DEF 14A
Definitive proxy
3 Apr 23
DEF 14A
Definitive proxy
4 Apr 22
DEFA14A
Additional proxy soliciting materials
19 Apr 21
DEFA14A
Additional proxy soliciting materials
19 Apr 21
DEF 14A
Definitive proxy
5 Apr 21
DEFA14A
Additional proxy soliciting materials
24 Apr 20
DEF 14A
Definitive proxy
30 Mar 20
DEF 14A
Definitive proxy
1 Apr 19
Other
UPLOAD
Letter from SEC
28 Apr 23
CORRESP
Correspondence with SEC
25 Apr 23
UPLOAD
Letter from SEC
11 Apr 23
UPLOAD
Letter from SEC
2 Apr 14
CORRESP
Correspondence with SEC
12 Mar 14
CORRESP
Correspondence with SEC
6 Mar 14
CORRESP
Correspondence with SEC
11 Feb 14
UPLOAD
Letter from SEC
6 Feb 14
CORRESP
Correspondence with SEC
23 Jan 14
CORRESP
Correspondence with SEC
31 Dec 13