KOP SCHEDULE 13D/A: Activist campaign
Simcoe Partners, L.P.
Filed with the SEC on · accession 0000921895-26-002844
KOP filed a SCHEDULE 13D/A (schedule 13d/a) with the SEC on Oct 22, 2026. A report the company filed with the SEC (the US market regulator). The stock moved -1.4% by the first close after the filing.
Summary of the filing
Simcoe Partners, L.P. filed an amended Schedule 13D disclosing sales of Koppers Holdings common stock over the past sixty days, totaling approximately 331,987 shares sold at prices ranging from about $41.02 to $47.17 per share.
Key details
How KOP stock reacted
Close before
$41.34
Oct 21, 2026
First close after
-1.43%
$40.75
5 trading days
+1.79%
$42.08
Since filing
-27.50%
$29.97
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Click hereFrequently asked questions
What did KOP file with the SEC on Oct 22, 2026?
KOP filed a SCHEDULE 13D/A (Activist campaign). Simcoe Partners, L.P. filed an amended Schedule 13D disclosing sales of Koppers Holdings common stock over the past sixty days, totaling approximately 331,987 shares sold at prices ranging from about $41.02 to $47.17 per share.
What does a activist campaign mean for KOP stock?
A settlement removes uncertainty; the stock often reacts to whether the amount is bigger or smaller than investors expected.
How do I read a SCHEDULE 13D/A?
A report the company filed with the SEC (the US market regulator). Start with the summary, then the key amounts and names. Compare it with the company’s earlier filings.
Why are SEC filings important?
Public companies must tell the SEC about anything that can change their value — results, leadership changes, big deals, new shares, bankruptcy. Filings are the official source, often before the news. A SCHEDULE 13D/A (schedule 13d/a): A report the company filed with the SEC (the US market regulator).
How did KOP stock react to this filing?
KOP closed at $41.34 before the filing and $40.75 on Oct 22, 2026 (-1.43%). Five trading days later: $42.08 (+1.79%).
Other KOP SEC filings
- 8-K · SEC filingNov 6, 2026
- 10-Q · SEC filingNov 6, 2026
- SCHEDULE 13G · SEC filingOct 30, 2026
- SCHEDULE 13G/A · SEC filingOct 19, 2026
- SCHEDULE 13G/A · SEC filingOct 8, 2026
- 10-Q · SEC filingAug 6, 2026
- 8-K · SEC filingAug 6, 2026
- 8-K · Cfo changeMay 11, 2026
- 8-K · Guidance cutMay 8, 2026
- 10-Q · Executive departureMay 8, 2026
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