Koppers Holdings Inc KOP

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Koppers Holdings Inc. Common Stock · Company · NYSE

Announcement types: (default: consequential filings)
Results & current reports
Capital markets
Ownership & governance

USD closing-price chart (daily close from yfinance · Last year)

USD 33.00 → 51.17 · 55.1%
51.47038.91026.350 1,2 3 4,5 6 7 8,9 10 11 12 13,14 15 Jul 25Oct 25Jan 26Apr 26Jul 26

Numbered dotted lines mark the filtered filings under Announcement Events below.

Price & SEC Filing History 22 Jul 2025 — 23 Jul 2026 (Last year)

Daily NYSE prices are sourced from yfinance. Yellow highlighting marks an intraday rise or a gap up between adjacent trading sessions. SEC acceptance times are converted to US Eastern time: pre-market filings appear below that day’s OHLCV row; filings accepted after the 09:30 ET open appear above it. The SEC does not publish an exact first-public-availability timestamp, so acceptance time is the best available proxy.

No data yet
51.4700 52.2500 50.3700 51.1700 70,756
49.7300 51.5400 48.6700 51.4700 163,400
49.1700 50.0700 47.7700 49.2000 205,400
Weekend
Weekend
48.5900 49.4600 48.3200 49.1400 217,000
48.0600 50.0000 48.0600 49.0500 222,300
48.7400 49.3000 48.0000 48.4700 145,100
48.2700 49.0000 48.0500 48.5300 78,500
47.6500 48.3600 47.2300 47.7700 116,300
Weekend
Weekend
46.9300 48.1200 46.4900 47.5600 115,600
47.4100 48.0000 46.4800 46.5900 159,600
46.6100 47.5200 45.3700 47.4000 144,500
46.8400 47.3200 45.1300 46.7600 202,900
45.9700 47.6800 45.7500 47.1000 149,800
Weekend
Weekend
No trading
44.9700 48.6300 44.9600 46.2100 255,700
44.7800 45.5600 44.4800 44.5600 126,300
45.0900 45.5400 44.6500 44.9000 123,200
44.8800 45.4500 43.9500 45.3600 157,800
Weekend
Weekend
44.3300 45.1300 44.0100 45.1200 322,200
44.4500 44.7500 43.6800 44.7000 154,800
42.9400 44.3600 42.7700 43.8800 157,400
43.8000 43.9000 42.7800 42.9000 136,000
43.4900 44.4600 42.6500 44.4200 291,800
Weekend
Weekend
No trading
43.9400 44.7400 43.4200 43.7300 385,900
44.5300 45.4400 43.6400 43.6500 153,400
44.6500 45.3300 44.2600 44.5000 183,900
44.0700 44.5500 43.6300 44.4000 183,900
Weekend
Weekend
41.9200 43.6600 41.8700 43.4100 160,800
42.1700 42.1700 40.8100 41.5200 110,500
41.7000 42.3100 41.4900 41.6800 167,200
41.9000 42.6000 40.8000 41.8600 145,700
41.2200 41.7600 40.6200 41.2200 178,100
Weekend
Weekend
42.0400 42.3800 40.6200 40.8100 167,200
43.3600 43.5700 41.7200 42.1600 272,200
42.0900 43.5200 41.8800 43.0900 230,100
41.1700 42.6100 40.6300 42.4800 124,500
40.5800 41.2900 40.2000 41.1900 115,000
Weekend
Weekend
40.9700 41.3600 40.6400 40.8000 228,400
42.4600 42.6100 41.1000 41.2900 107,900
41.7000 42.7700 41.7000 42.7300 141,900
41.5700 42.0000 40.8500 41.5400 174,100
No trading
Weekend
Weekend
40.0500 40.5800 39.5400 40.3600 120,100
38.5600 39.6700 38.5000 39.6300 150,800
38.2200 39.4900 38.1400 39.2000 160,700
39.8600 39.9600 38.1300 38.3100 223,600
40.7300 41.9600 40.3900 40.3900 204,400
Weekend
Weekend
42.2300 42.2300 40.3300 40.6800 233,700
43.2300 43.8800 41.9400 42.4100 367,500
43.7700 44.6700 42.3000 42.6900 294,100
42.9900 44.1000 42.4200 43.5500 328,900
44.0000 44.0000 41.9100 43.0800 253,100
15 · 8-K Pre-market · 09:05 ET 8-K ↗
Weekend
Weekend
14 · 10-Q After market open · 12:05 ET 10-Q ↗
44.3800 46.4000 42.4500 43.9900 334,000
13 · 8-K Pre-market · 09:10 ET 8-K ↗ 12 · 8-K/A After-hours · 16:18 ET 8-K/A ↗
41.4900 42.4100 41.0900 41.1600 176,900
41.8000 42.0400 40.1800 41.6100 102,800
40.0400 41.8900 39.5000 41.3500 121,000
41.7000 41.7400 39.5000 39.8400 148,500
Weekend
Weekend
41.0900 41.9300 41.0000 41.9100 145,900
39.7300 41.0600 39.7300 40.8300 109,600
41.6100 41.6100 39.7500 39.8000 166,500
41.5000 42.1700 40.9100 41.4600 193,700
40.4700 41.4200 40.3100 41.3500 153,500
Weekend
Weekend
39.0000 40.4900 38.8500 40.2800 169,000
38.1200 38.8000 37.6600 38.6500 129,000
38.0600 38.0600 37.4200 38.0100 83,200
37.5800 38.1900 36.7400 37.5200 150,300
37.5800 37.9600 37.3500 37.4400 71,700
Weekend
Weekend
36.9200 38.1300 36.5600 37.6900 161,800
37.3500 37.8500 36.7700 36.9800 125,400
38.2700 38.2700 37.4300 37.5400 102,100
38.2800 38.8900 37.9000 38.4400 122,300
37.4600 38.4600 37.1400 38.4200 118,000
Weekend
Weekend
37.0700 37.5000 37.0700 37.4400 87,600
37.2100 37.6100 36.7000 37.0400 147,500
37.2000 37.5000 36.9300 37.3600 186,700
35.7500 36.7300 35.6200 36.6700 217,700
37.1800 37.1900 35.6800 35.7900 212,500
Weekend
Weekend
No trading
36.9400 37.8400 36.3100 37.2900 237,300
38.5900 38.9300 37.5400 37.6500 200,600
38.6100 39.0900 37.9700 38.6800 171,500
38.4700 38.5400 38.0000 38.2400 205,000
Weekend
Weekend
11 · DEF 14A After-hours · 16:30 ET DEF 14A ↗
38.3200 38.6700 37.5400 37.9200 136,600
37.6500 38.8400 37.6500 38.7700 272,500
37.4700 37.8800 36.8300 37.8700 175,200
35.8800 37.3000 35.8800 37.2100 155,800
35.9700 36.7300 35.7300 36.1000 235,400
Weekend
Weekend
37.8700 38.1400 35.0100 35.1000 1,281,200
37.4300 37.7500 36.8100 37.4500 291,600
10 · 8-K/A After-hours · 16:45 ET 8-K/A ↗
37.5700 38.0500 37.3100 37.3500 310,300
38.6800 39.5000 37.6500 37.7200 225,200
37.9200 39.0700 37.9200 38.3900 258,800
Weekend
Weekend
37.5000 37.8100 37.2200 37.7700 272,600
37.1700 38.3900 37.1700 37.3600 251,900
37.0500 38.1700 36.8900 37.2800 291,900
38.0100 38.1100 37.0700 37.1900 327,500
37.1400 38.7700 36.4100 38.5300 418,800
Weekend
Weekend
37.6000 38.0800 36.9300 37.5500 290,800
37.9700 39.2700 37.2000 38.0200 247,400
36.8900 38.7400 35.9500 38.5500 342,200
35.1200 36.7600 34.5900 36.7300 257,300
37.5100 37.5100 35.3000 36.4200 327,800
Weekend
Weekend
36.7400 38.2100 36.1000 37.8000 342,700
9 · 10-K After market open · 12:17 ET 10-K ↗
35.5000 37.5200 34.9200 37.2400 186,700
8 · 8-K Pre-market · 08:59 ET 8-K ↗
34.5100 34.5900 33.4400 34.5200 104,700
33.8900 34.6800 33.7600 34.4200 120,600
34.9800 34.9800 33.5100 33.7200 161,000
Weekend
Weekend
34.8100 35.1600 34.1600 35.1100 129,400
35.0700 35.1200 34.1400 34.6100 124,600
35.0700 35.7000 34.6300 35.0600 199,900
34.1200 35.4400 33.1400 35.0700 178,600
No trading
Weekend
Weekend
34.2900 34.8100 34.0000 34.3000 209,800
34.5300 34.9100 33.5200 34.2200 243,500
33.3500 34.2100 32.9200 34.2100 154,700
32.6300 33.6200 32.6300 33.2000 155,000
32.2500 32.7700 31.6600 32.5000 112,300
Weekend
Weekend
31.8300 32.5100 31.5700 32.3000 168,500
31.2400 31.6700 30.8300 31.5000 174,800
30.5700 31.8800 30.4600 31.2200 200,300
29.5800 30.7400 29.3300 30.3100 145,700
29.4700 30.0000 29.1500 29.6900 155,700
Weekend
Weekend
29.2200 29.8300 28.9900 29.4600 156,000
29.4400 29.6800 29.0000 29.6200 147,500
29.1200 29.2800 28.7900 29.2400 91,700
29.0600 29.1700 28.7700 29.1200 83,800
29.0300 29.2200 28.6500 29.1300 94,400
Weekend
Weekend
29.3400 29.4600 28.8800 28.9700 97,100
29.8500 30.2200 29.3700 29.4500 123,800
28.2200 29.6000 28.2200 29.5200 126,500
28.5000 28.5600 27.9600 28.1600 112,400
No trading
Weekend
Weekend
28.9200 29.2500 28.7500 29.0800 170,400
29.3900 29.6600 29.0200 29.2400 100,500
28.9000 29.7200 28.6700 29.3600 133,300
28.9200 29.9100 28.7100 28.7400 117,000
28.2500 29.0100 27.4900 28.9300 115,600
Weekend
Weekend
27.0400 28.4700 26.8100 28.3300 220,000
7 · 8-K Pre-market · 08:15 ET 8-K ↗
26.8000 27.8300 26.7700 27.6200 85,700
27.6500 27.7700 26.7900 26.9300 123,900
26.7500 27.7200 26.5500 27.6300 247,800
26.5200 27.4900 26.5200 26.9300 102,500
Weekend
Weekend
27.0400 27.2900 26.6500 26.6700 122,900
No trading
27.3900 27.4800 27.0000 27.0800 116,400
27.2000 27.6000 27.0100 27.3500 115,600
26.9400 27.3100 26.6400 27.2900 139,900
Weekend
Weekend
27.1500 27.2400 26.7600 26.9500 119,300
No trading
26.8900 27.2900 26.8800 27.2500 54,900
27.2600 27.3300 26.7600 26.8500 80,800
27.4200 28.1300 27.2100 27.2700 182,000
Weekend
Weekend
27.9200 28.0000 27.0800 27.4900 325,900
28.1700 28.6800 27.8800 28.1300 143,100
28.5100 28.8300 28.1700 28.3000 106,600
28.4700 29.0400 28.1200 28.6200 220,600
29.0600 29.4700 28.4200 28.4900 120,300
Weekend
Weekend
29.2500 29.8000 28.9200 29.0100 151,500
29.0400 29.3400 28.7200 29.2600 109,500
27.6900 29.0900 27.6900 28.7800 192,800
28.2500 28.4100 27.4700 27.7900 165,200
28.0800 28.6100 27.8700 28.0500 154,000
Weekend
Weekend
27.8400 28.4900 27.8400 28.0100 106,200
29.0800 29.2500 27.9900 28.0500 115,200
6 · 8-K/A After-hours · 16:35 ET 8-K ↗
29.2400 29.7100 28.8100 29.2000 105,900
29.7700 29.7700 28.9200 29.2200 133,600
29.4300 30.0800 29.4300 29.6200 90,200
Weekend
Weekend
29.6200 29.9100 29.4000 29.6700 94,300
No trading
29.5500 30.3500 29.5500 29.7000 196,000
28.7500 30.1300 28.7100 29.8900 195,200
28.2600 28.6400 27.7000 28.5500 166,000
Weekend
Weekend
27.4000 28.8100 27.2300 28.2100 206,100
28.0900 28.4400 27.1800 27.2900 98,600
27.9700 28.0400 27.4600 27.7400 141,300
27.7200 28.4900 27.4900 27.9300 160,700
28.9800 28.9900 27.8400 27.8600 186,400
Weekend
Weekend
29.3400 29.7500 28.5100 28.9400 234,900
28.4300 29.5800 28.1400 29.3900 196,700
28.4400 28.9500 28.1800 28.5500 172,100
27.8900 28.3700 27.3700 28.3000 227,600
27.0000 27.8900 26.0200 27.7000 182,200
Weekend
Weekend
5 · 10-Q After market open · 12:37 ET 10-Q ↗
28.6500 28.6500 25.0000 26.7000 212,900
4 · 8-K Pre-market · 08:22 ET 8-K ↗
28.1500 30.0000 27.7400 27.8400 174,500
3 · 8-K After-hours · 16:35 ET 8-K ↗
28.0700 28.6100 27.7700 28.0500 182,900
27.8600 28.4800 26.9300 28.2400 135,200
28.0100 28.3900 27.5200 28.1700 174,100
Weekend
Weekend
27.5800 28.3900 27.1000 28.2200 162,500
28.6700 28.6700 27.2600 27.6100 162,600
29.3800 29.8300 28.8200 29.2500 219,500
29.1900 29.5900 28.8200 29.3700 139,400
29.3600 29.6300 28.9600 29.4100 152,000
Weekend
Weekend
29.1200 29.4400 29.0700 29.1400 85,600
28.6200 29.0400 28.3000 28.7200 104,700
28.0000 28.4400 27.9400 28.3800 145,000
27.0200 28.0300 27.0000 27.9900 153,300
26.9200 27.1500 26.5700 27.0100 119,400
Weekend
Weekend
26.5100 26.9000 26.4500 26.7400 131,100
26.4900 26.7400 26.1700 26.7400 116,400
26.9000 27.3900 26.2600 26.4300 101,900
26.3800 26.9900 26.3800 26.6900 94,700
26.7400 26.9400 26.5500 26.7400 146,700
Weekend
Weekend
26.5400 26.8400 26.1600 26.3500 181,300
26.6000 26.7900 26.3400 26.5000 191,000
26.6400 26.6500 26.3000 26.5900 114,800
26.7500 27.1300 26.3700 26.4700 153,100
27.1400 27.1400 26.2200 26.7400 175,200
Weekend
Weekend
27.1400 27.4900 26.9100 27.0000 157,800
27.7900 28.0700 26.9100 26.9400 137,800
27.7400 27.9800 27.4600 27.9000 135,300
27.5700 28.2200 27.3900 28.0000 123,800
28.6000 28.6300 27.7500 27.7500 138,800
Weekend
Weekend
28.1500 28.6800 28.1500 28.4100 121,900
28.7500 28.7500 28.1000 28.1500 127,700
28.8100 28.9500 28.6400 28.8200 114,600
28.8700 29.4900 28.7300 28.7500 224,800
28.8300 29.0200 28.5700 28.8900 227,100
Weekend
Weekend
29.3200 29.3600 28.5600 29.0000 591,400
29.2200 29.5500 28.8600 29.3500 222,000
28.7300 29.9000 28.5300 28.9800 290,300
28.6700 29.1600 28.4300 28.6300 132,800
28.8800 28.9600 28.2900 28.6300 140,000
Weekend
Weekend
28.6500 28.9800 28.1400 28.7500 177,700
27.4900 28.9800 27.4900 28.9000 199,100
28.6500 28.8200 27.3800 27.5300 137,900
28.3900 28.9400 28.1900 28.6900 198,400
28.9100 28.9400 28.3500 28.6700 170,800
Weekend
Weekend
28.5900 29.9900 28.5000 28.8700 159,600
28.2200 28.6900 27.9700 28.6200 172,000
28.1400 28.9800 27.2400 28.0800 173,100
28.6500 28.8900 28.2400 28.3200 174,800
No trading
Weekend
Weekend
29.0400 29.1600 28.6500 28.9800 135,700
29.4000 29.4700 28.9400 29.0100 172,900
29.2300 29.7400 28.7500 29.2300 130,000
29.6500 29.7900 29.2300 29.3900 138,900
30.2200 30.2200 29.2300 29.7000 127,400
Weekend
Weekend
29.2700 30.4700 28.9400 30.1600 148,800
28.8500 29.3000 28.6400 28.7900 266,700
29.7800 29.9000 29.2500 29.3300 138,400
29.7800 30.3000 29.5300 29.8500 143,100
29.5400 29.9000 29.4600 29.6200 160,400
Weekend
Weekend
30.8100 30.8900 29.5200 29.6100 223,000
30.4400 31.0100 30.4300 30.6400 168,400
30.0000 31.1800 30.0000 31.0600 169,100
28.9300 30.4000 28.5000 29.6500 265,600
28.7400 29.0400 26.8200 28.3500 308,100
Weekend
Weekend
2 · 10-Q After market open · 11:59 ET 10-Q ↗
28.7600 29.5700 26.7900 28.8400 405,300
1 · 8-K Pre-market · 08:10 ET 8-K ↗
32.9500 33.4600 32.7200 33.2700 96,600
32.4900 32.6000 32.2400 32.4400 79,000
31.9100 32.7500 31.9100 32.6200 102,900
31.9900 32.3600 31.7300 31.8500 87,500
Weekend
Weekend
32.4900 32.4900 31.4100 31.8900 116,700
32.6700 33.1200 32.5100 32.8600 121,500
33.7600 33.7600 32.8300 33.1000 114,000
34.1800 34.1800 33.6900 33.8200 99,800
34.5000 34.7000 33.8400 34.0500 94,700
Weekend
Weekend
33.4300 34.6500 33.4000 34.5900 100,800
33.8400 34.0800 33.2800 33.4900 116,100
33.6000 34.3100 33.3200 34.2900 110,300
32.4100 33.1900 32.3300 33.0000 180,800

Announcement Events

Each title opens the filing on the SEC website. Registered users can summarise the filing and up to seven relevant exhibits linked within the same SEC submission.

15 8-K 8-K (opens SEC filing in a new tab) Pre-market · 09:05 ET Summarise
14 10-Q 10-Q (opens SEC filing in a new tab) After market open · 12:05 ET Summarise
13 8-K 8-K (opens SEC filing in a new tab) Pre-market · 09:10 ET Summarise
12 8-K/A 8-K/A (opens SEC filing in a new tab) After-hours · 16:18 ET Summarise
11 DEF 14A DEF 14A (opens SEC filing in a new tab) After-hours · 16:30 ET Summarise
10 8-K/A 8-K/A (opens SEC filing in a new tab) After-hours · 16:45 ET Summarise
9 10-K 10-K (opens SEC filing in a new tab) After market open · 12:17 ET Summarise
8 8-K 8-K (opens SEC filing in a new tab) Pre-market · 08:59 ET Summarise
7 8-K 8-K (opens SEC filing in a new tab) Pre-market · 08:15 ET Summarise
6 8-K/A 8-K (opens SEC filing in a new tab) After-hours · 16:35 ET Summarise
5 10-Q 10-Q (opens SEC filing in a new tab) After market open · 12:37 ET Summarise
4 8-K 8-K (opens SEC filing in a new tab) Pre-market · 08:22 ET Summarise
3 8-K 8-K (opens SEC filing in a new tab) After-hours · 16:35 ET Summarise
2 10-Q 10-Q (opens SEC filing in a new tab) After market open · 11:59 ET Summarise
1 8-K 8-K (opens SEC filing in a new tab) Pre-market · 08:10 ET Summarise