CSTL
CASTLE BIOSCIENCES INC · Healthcare · Market cap $1.1B
Insiders sold $7.5M net in the last 90 days ·4 sellers, 0 buyers· 22 of 25 sales under Rule 10b5-1 plans· latest Form 4 filed Sep 16, 2026
Insider Buying
$0
reported purchases (SEC code P)
Insider Selling
$17.7M
reported sales (SEC code S)
Unique Insiders
5
in the rolling window
Latest filing
Sep 16, 2026
Juvenal Tobin W
CASTLE BIOSCIENCES INC (CSTL) has 79 SEC Form 4 filings (275 transaction rows) in the rolling window, disclosed by 5 distinct insiders. Most recent filing: Sep 16, 2026.
Inside the rolling window, 5 insiders at CASTLE BIOSCIENCES INC reported no open-market purchases and 72 open-market sales totaling $17.7M. The most active filer is Pres. & Chief Exec. Officer MAETZOLD DEREK J with 43 filings. Insiders have net sold $8.4M over the trailing 6 months. The most recent open-market filing is a sale of 3,306 shares by Chief Commercial Officer Juvenal Tobin W, dated Sep 14, 2026, worth $107K.
- Industry:Medical - Diagnostics & Research
- CEO:Derek J. Maetzold
- Employees:784
- HQ:Friendswood, TX, US
- IPO:2019-07-25
| Source | |||||||
|---|---|---|---|---|---|---|---|
| Chief Commercial Officer | Sale | 3,306 | $107K | Sep 16 | — | SEC ↗ | |
| Chief Commercial Officer | Sale | 3,294 | $116K | Sep 16 | — | SEC ↗ | |
| Pres. & Chief Exec. Officer | Sale | 14,518 | $465K | Sep 15 | — | SEC ↗ | |
| Chief Operating Officer | Sale | 4,152 | $139K | Sep 3 | +8.7% | SEC ↗ | |
| Chief Commercial Officer | Sale | 1,730 | $57K | Sep 2 | — | SEC ↗ | |
| Pres. & Chief Exec. Officer | Sale | 17,726 | $588K | Sep 1 | — | SEC ↗ | |
| Chief Commercial Officer | Sale | 9,050 | $317K | Aug 27 | — | SEC ↗ | |
| Chief Operating Officer | Sale | 12,218 | $412K | Aug 26 | — | SEC ↗ | |
| Chief Operating Officer | Sale | 12,384 | $426K | Aug 26 | — | SEC ↗ | |
| Chief Commercial Officer | Sale | 1,730 | $51K | Aug 19 | — | SEC ↗ | |
| Pres. & Chief Exec. Officer | Sale | 6,398 | $192K | Aug 18 | — | SEC ↗ | |
Stokes FrankFirst in 5 months | Chief Financial Officer | Sale | 24,908 | $742K | Aug 18 | — | SEC ↗ |
| Chief Commercial Officer | Sale | 1,301 | $50K | Aug 6 | — | SEC ↗ | |
| Pres. & Chief Exec. Officer | Sale | 35,441 | $1.1M | Aug 6 | — | SEC ↗ | |
| Pres. & Chief Exec. Officer | Sale | 3,575 | $110K | Aug 6 | — | SEC ↗ | |
| Chief Operating Officer | Sale | 8,586 | $256K | Aug 5 | — | SEC ↗ | |
| Pres. & Chief Exec. Officer | Sale | 10,153 | $306K | Aug 4 | — | SEC ↗ | |
| Pres. & Chief Exec. Officer | Sale | 18,493 | $561K | Aug 4 | — | SEC ↗ | |
Juvenal Tobin WFirst in 5 months | Chief Commercial Officer | Sale | 17,310 | $507K | Aug 4 | — | SEC ↗ |
Juvenal Tobin WFirst in 5 months | Chief Commercial Officer | Sale | 1,730 | $49K | Aug 4 | — | SEC ↗ |
| Pres. & Chief Exec. Officer | Sale | 9,002 | $218K | Jul 29 | — | SEC ↗ | |
| Pres. & Chief Exec. Officer | Sale | 3,338 | $77K | Jul 16 | — | SEC ↗ | |
| Pres. & Chief Exec. Officer | Sale | 9,002 | $219K | Jul 6 | — | SEC ↗ | |
| Chief Operating Officer | Sale | 8,586 | $210K | Jul 6 | — | SEC ↗ | |
Oelschlager Kristen MFirst in 6 months | Chief Operating Officer | Sale | 8,587 | $178K | Jun 18 | — | SEC ↗ |
Congress trading CSTL 3 all-time
- DRep. Josh S. GottheimerOther$1,001 - $15,0002022-03-15
- DRep. Gilbert Ray CisnerosPurchase$1,001 - $15,0002020-12-23
- DRep. Josh S. GottheimerPurchase$1,001 - $15,0002020-12-21
STOCK Act disclosures are filed up to 45 days after the trade. Amount is a disclosed range, not an exact figure.
Frequently asked questions
How many SEC Form 4 insider filings does CSTL have?
CASTLE BIOSCIENCES INC (CSTL) has 79 SEC Form 4 filings (275 transaction rows) in the rolling 365-day window, disclosed by 5 distinct insiders. Most recent filing: Sep 16, 2026.
When was the most recent SEC Form 4 filing for CSTL?
The most recent Form 4 filing for CSTL on Tracefour is dated Sep 16, 2026.
Who is the most active insider at CSTL?
The most active SEC Form 4 filer at CSTL in the rolling window is Pres. & Chief Exec. Officer MAETZOLD DEREK J, with 43 filings.
What is the net insider flow at CSTL over the last 6 months?
Over the trailing 180 days, insiders at CSTL have net sold $8.4M based on SEC Form 4 disclosures.
What is the total insider buy and sell value at CSTL in the current window?
Inside the rolling window, insiders at CSTL bought $0 and sold $17.7M based on SEC Form 4 filings.
Can I get alerts for CSTL insider trading?
Yes. Tracefour sends a free email when a new SEC Form 4 purchase or sale is filed at CASTLE BIOSCIENCES INC (CSTL). Alerts are set per company from the page itself, there is no paid tier, and each email links to the original filing on SEC EDGAR.
Related companies
CASTLE BIOSCIENCES INC is in the Healthcare sector.