Castle Biosciences, Inc. (CSTL) has 12 known insider and institutional holders on record. The largest holder is Juvenal Tobin W with 86,825 shares. Other notable holders include Stokes Frank and Oelschlager Kristen M.
Over the last 12 months, insiders have made 59 transactions in CSTL stock — 14 buys (valued at RSU Award) and 23 sells (valued at $4.5M). Insider selling has exceeded buying during this period.
CSTL Insider Ownership
Top Holder
Juvenal Tobin W
86,825 shares
Buys (12 mo)
14
$0.00 value
Sells (12 mo)
23
$4.5M value
12-Month Transaction Activity
Top Insider Holders
| # |
Name |
Role |
Shares Owned |
Last Filed |
Relative Size |
| 1 |
Juvenal Tobin W |
Chief Commercial Officer |
86,825 |
2026-03-16 |
|
| 2 |
Stokes Frank |
Chief Financial Officer |
60,085 |
2026-03-09 |
|
| 3 |
Oelschlager Kristen M |
Chief Operating Officer |
20,068 |
2026-03-05 |
|
| 4 |
Cole G Bradley |
Director |
19,309 |
2026-03-09 |
|
| 5 |
Bradbury Daniel |
Director |
13,667 |
2025-05-23 |
|
| 6 |
Harrison Miles |
Director |
13,667 |
2025-05-23 |
|
| 7 |
Goldberg Ellen |
Director |
13,667 |
2025-05-23 |
|
| 8 |
Caple Kim |
Director |
13,667 |
2025-05-23 |
|
| 9 |
Olson Tiffany |
Director |
13,667 |
2025-05-23 |
|
| 10 |
Aspinall Mara G. |
Director |
8,636 |
2023-05-30 |
|
| 11 |
Cotton Rodney |
Director |
5,330 |
2026-03-30 |
|
| 12 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
3,058 |
2026-03-30 |
|
Recent Transactions (last 12 months)
| Date |
Name |
Role |
Type |
Shares |
Price |
Value |
| 2026-03-26 |
Cotton Rodney |
Director |
Option Exercise (Sell) |
5,329 |
- |
- |
| 2026-03-26 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
Informative Sell |
278 |
$25.55 |
$7.1K |
| 2026-03-18 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
Informative Sell |
650 |
$25.39 |
$16.5K |
| 2026-03-17 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
Informative Sell |
18,650 |
$25.93 |
$483.59K |
| 2026-03-16 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
Informative Sell |
126 |
$26.68 |
$3.36K |
| 2026-03-13 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
Informative Sell |
13,204 |
$25.45 |
$336K |
| 2026-03-12 |
Juvenal Tobin W |
Chief Commercial Officer |
Informative Sell |
20,863 |
$25.24 |
$526.58K |
| 2026-03-12 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
Informative Sell |
23,179 |
$25.28 |
$585.94K |
| 2026-03-11 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
Informative Sell |
279 |
$26.11 |
$7.28K |
| 2026-03-05 |
Stokes Frank |
Chief Financial Officer |
Informative Sell |
6,001 |
$27.98 |
$167.91K |
| 2026-03-05 |
Cole G Bradley |
Director |
Informative Sell |
2,655 |
$28.51 |
$75.69K |
| 2026-03-04 |
Oelschlager Kristen M |
Chief Operating Officer |
Option Exercise (Sell) |
13,811 |
- |
- |
| 2026-03-03 |
Oelschlager Kristen M |
Chief Operating Officer |
Tax Withholding of RSU |
2,427 |
$27.57 |
$66.91K |
| 2026-03-04 |
Juvenal Tobin W |
Chief Commercial Officer |
Option Exercise (Sell) |
13,811 |
- |
- |
| 2026-03-03 |
Juvenal Tobin W |
Chief Commercial Officer |
RSU Award |
48,367 |
- |
- |
| 2026-03-04 |
Stokes Frank |
Chief Financial Officer |
Option Exercise (Sell) |
3,800 |
$3.38 |
$12.84K |
| 2026-03-03 |
Stokes Frank |
Chief Financial Officer |
RSU Award |
48,367 |
- |
- |
| 2026-03-04 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
Option Exercise (Sell) |
31,110 |
- |
- |
| 2026-03-03 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
Tax Withholding of RSU |
19,043 |
$27.57 |
$525.02K |
| 2026-02-04 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
Informative Sell |
171 |
$38.61 |
$6.6K |
| 2026-02-03 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
Informative Sell |
3,200 |
$39.91 |
$127.72K |
| 2026-01-20 |
Maetzold Derek J |
Pres. & Chief Exec. Officer |
Informative Sell |
4,017 |
$40.01 |
$160.73K |
| 2026-01-12 |
Oelschlager Kristen M |
Chief Operating Officer |
RSU Award |
9,207 |
- |
- |
| 2026-01-12 |
Juvenal Tobin W |
Chief Commercial Officer |
RSU Award |
9,207 |
- |
- |
| 2026-01-12 |
Stokes Frank |
Chief Financial Officer |
RSU Award |
8,124 |
- |
- |
