Form 4 for CSTL CASTLE BIOSCIENCES INC
Accepted 2026-03-09 00:00:00 ET · period of report 2026-03-05 · accession 0001447362-26-000008 · SEC index · Original document
Summary rows
Aggregated the way they appear in lists: one row per insider, transaction code and security table.
| X | Filed | Traded | Ticker | Insider | Title | Type | Price | Qty | Owned | ΔOwn | Value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| DM | 2026-03-09 | 2026-03-05 | CSTL | Cole G Bradley | Dir | S - Sale+OE | $28.47 | -7,403 | 19.3K | -28% | -$210.7K |
| D | 2026-03-09 | 2026-03-05 | CSTL | Cole G Bradley | Dir | M - OptEx | $3.38 | +4,748 | 26.7K | +22% | +$16.0K |
| D | 2026-03-09 | 2026-03-05 | CSTL | Cole G Bradley | Dir | M - OptEx | $0.00 | -4,748 | 20.0K | -19% | $0 |
Purchase Sale Sale after option exercise All abbreviations
Every reported transaction
| # | Table | Security | Date | Code | A/D | Shares | Price | Owned after | Own | Exercise / expiry | Underlying | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Common | Common Stock | 2026-03-05 | S | D | 4,748 | $28.44 | 21,964 | D | — | — | (F1) This transaction was executed in multiple trades at prices ranging from $28.39 to $28.51, inclusive. The price reported above reflects the weighted-average sale price. The Reporting Person hereby undertakes to provide upon request to the Securities and Exchange Commission staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. |
| 2 | Common | Common Stock | 2026-03-05 | S | D | 2,655 | $28.51 | 19,309 | D | — | — | (F2) This transaction was executed in multiple trades at prices ranging from $28.47 to $28.57, inclusive. The price reported above reflects the weighted-average sale price. The Reporting Person hereby undertakes to provide upon request to the Securities and Exchange Commission staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. |
| 3 | Common | Common Stock | 2026-03-05 | M | A | 4,748 | $3.38 | 26,712 | D | — | — | |
| 4 | Derivative | Stock option (right to buy) | 2026-03-05 | M | D | 4,748 | $0.00 | 20,000 | D | $3.38 · — to 2029-03-11 | 4,748 Common Stock | (F3) The shares subject to the option are fully vested. |