Updated Jul 16, 2026
Kirby William C. is a corporate insider tracked by InsiderAlpha. No SEC Form 4 filings recorded in the last 90 days. Lifetime open-market purchases: $3.29M.
William C. Kirby is a corporate insider associated with Cabot Corp (CBT) as referenced in an SEC filing with CIK 0001413483. The most recent filing date provided is 2026-01-12, and it reports zero stock purchases and zero stock sales, with a total of one filing on that date. The SEC filing context does not disclose a specific role or title for Mr. Kirby beyond insider status.
| Role | Insider |
|---|---|
| Notability | 25/100 |
| Date | Ticker | Company | Code | Shares | Price | Value |
|---|---|---|---|---|---|---|
| 2026-02-28 | TWN | TAIWAN FUND INC | P — Open-market purchase | 50.7K | $64.90 | $3.29M |
| 2026-01-12 | CBT | CABOT CORP | A — Grant or award | 486 | $0.00 |
William C. Kirby is a corporate insider associated with Cabot Corp (CBT) as referenced in an SEC filing with CIK 0001413483. The most recent filing date provided is 2026-01-12, and it reports zero stock purchases and zero stock sales, with a total of one filing on that date. The SEC filing context does not disclose a specific role or title for Mr. Kirby beyond insider status.…
Recorded transactions: 1 open-market purchases ($3.29M) and 0 open-market sales () across all tracked filings.
All Form 4 filings, transaction values, and 10b5-1 plan flags are listed on this page and updated in real time as new SEC EDGAR filings are processed.
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