🕵️ Castle Biosciences Inc ($CSTL)
SEC insider & ownership activity, last 12 months · CIK 1447362 · every row links its SEC filing
Over the last 12 months insiders sold $12.2M with no open-market buying against it. Derek J. Maetzold sold $7.7M through a 10b5-1 trading plan in 129 lots (Aug–Jul). No red-flag 8-Ks in the window.
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Monthly net open-market insider flow, last 12 months (up = net buying)
Insider flow
0 buyers, $0 (0 lots) · 5 sellers, $12.2M (148 lots)
| Insider | Buys | Bought | Sells | Sold | Last |
|---|---|---|---|---|---|
| Derek J. Maetzold | 0 | – | 129 | $7.7M | Jul 27, 2026 |
| Kristen Oelschlager | 0 | – | 7 | $2.3M | Jul 1, 2026 |
| Tobin W. Juvenal | 0 | – | 5 | $1.2M | Mar 12, 2026 |
| Stokes Frank | 0 | – | 5 | $717K | Mar 5, 2026 |
| Cole G Bradley | 0 | – | 2 | $211K | Mar 5, 2026 |
5%+ holders
| Holder | Stake | Class | Schedule | Event | |
|---|---|---|---|---|---|
| RTW Investments, LP | 9.3% | 13G | May 15, 2026 | filing ↗ | |
| Roderick Wong | 9.3% | 13G | May 15, 2026 | filing ↗ | |
| Blackrock, Inc. | 8.2% | 13G | Apr 23, 2025 | filing ↗ |
Planned insider sales (Form 144)
| Seller | Planned | Approx. sale date | |
|---|---|---|---|
| Derek Maetzold | $589K | Jul 1, 2026 | filing ↗ |
| Kristen Oelschlager | $618K | Jun 16, 2026 | filing ↗ |
| Derek Maetzold | $294K | Jun 1, 2026 | filing ↗ |
| Derek Maetzold | $270K | May 7, 2026 | filing ↗ |
| Derek Maetzold | $449K | Mar 26, 2026 | filing ↗ |
| Tobin Juvenal | $528K | Mar 12, 2026 | filing ↗ |
| Derek Maetzold | $2.5M | Mar 11, 2026 | filing ↗ |
| Franklin Stokes | $169K | Mar 5, 2026 | filing ↗ |
| Gordon B. Cole | $211K | Mar 5, 2026 | filing ↗ |
| Franklin Stokes | $196K | Mar 3, 2026 | filing ↗ |
| Derek Maetzold | $470K | Jan 5, 2026 | filing ↗ |
| Kristen M. Oelschlager | $581K | Dec 17, 2025 | filing ↗ |
| Derek Maetzold | $1.3M | Dec 15, 2025 | filing ↗ |
| Tobin Juvenal | $495K | Dec 11, 2025 | filing ↗ |
| Franklin M. Stokes | $168K | Dec 11, 2025 | filing ↗ |
| Derek Maetzold | $428K | Nov 25, 2025 | filing ↗ |
| Tobin Juvenal | $49K | Nov 24, 2025 | filing ↗ |
| Kristen M. Oelschlager | $658K | Nov 11, 2025 | filing ↗ |
| Tobin Juvenal | $187K | Nov 11, 2025 | filing ↗ |
| Franklin Stokes | $187K | Nov 11, 2025 | filing ↗ |
| Derek Maetzold | $424K | Nov 4, 2025 | filing ↗ |
| Derek Maetzold | $89K | Oct 2, 2025 | filing ↗ |
| Kristen M. Oelschlager | $384K | Aug 27, 2025 | filing ↗ |
| Kristen M. Oelschlager | $541K | Aug 27, 2025 | filing ↗ |
| Derek Maetzold | $81K | Aug 15, 2025 | filing ↗ |
| Derek Maetzold | $835K | Aug 13, 2025 | filing ↗ |
Material events (8-K)
| Item | Event date | |
|---|---|---|
| Shareholder vote (5.07) | May 28, 2026 | filing ↗ |
| Earnings (2.02) | May 6, 2026 | filing ↗ |
| Reg FD disclosure (7.01) | May 6, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | May 6, 2026 | filing ↗ |
| Earnings (2.02) | Feb 26, 2026 | filing ↗ |
| Reg FD disclosure (7.01) | Feb 26, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Feb 26, 2026 | filing ↗ |
| Earnings (2.02) | Jan 11, 2026 | filing ↗ |
| Reg FD disclosure (7.01) | Jan 11, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Jan 11, 2026 | filing ↗ |
| Earnings (2.02) | Nov 3, 2025 | filing ↗ |
| Reg FD disclosure (7.01) | Nov 3, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Nov 3, 2025 | filing ↗ |
| Charter/bylaw changes (5.03) | Aug 5, 2025 | filing ↗ |
| Earnings (2.02) | Aug 4, 2025 | filing ↗ |
| Reg FD disclosure (7.01) | Aug 4, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Aug 4, 2025 | filing ↗ |