Over the past year there were no insider purchases at Castle Biosciences Inc. Five insiders sold roughly $19.3 million instead.
Selling on its own is common and often pre-planned (10b5-1 plans, taxes, diversification), so it matters more when it is unusually heavy or broad.
Looking at the quarterly pattern: 7 quarters in a row of net selling by insiders. Insiders bought in 0 of the last 7 full quarters. Big money check: 176 institutions held CSTL as of Q2 2026, and more funds bought than sold.
| Filed | Insider | Role | Type | Shares | Price | Value | Source |
|---|---|---|---|---|---|---|---|
| Oct 7, 2026 | MAETZOLD DEREK J | Executive Officer | Sell | 8,580 | $35.57 | $305K | SEC |
| Oct 7, 2026 | MAETZOLD DEREK J | Executive Officer | Sell | 2,718 | $35.57 | $97K | SEC |
| Oct 7, 2026 | MAETZOLD DEREK J | Executive Officer | Sell | 3,198 | $35.57 | $114K | SEC |
| Oct 5, 2026 | Oelschlager Kristen M | COO | Sell | 2,807 | $35.75 | $100K | SEC |
| Oct 5, 2026 | Oelschlager Kristen M | COO | Sell | 1,346 | $36.38 | $49K | SEC |
| Oct 1, 2026 | Juvenal Tobin W | Executive Officer | Sell | 5,543 | $35.50 | $197K | SEC |
| Oct 1, 2026 | Juvenal Tobin W | Executive Officer | Sell | 1,034 | $34.20 | $35K | SEC |
| Sep 23, 2026 | MAETZOLD DEREK J | Executive Officer | Sell | 2,718 | $35.33 | $96K | SEC |
| Sep 23, 2026 | MAETZOLD DEREK J | Executive Officer | Sell | 3,198 | $35.33 | $113K | SEC |
| Sep 23, 2026 | MAETZOLD DEREK J | Executive Officer | Sell | 8,580 | $35.33 | $303K | SEC |
| Sep 16, 2026 | Juvenal Tobin W | Executive Officer | Sell | 3,306 | $32.32 | $107K | SEC |
| Sep 16, 2026 | Juvenal Tobin W | Executive Officer | Sell | 3,294 | $35.14 | $116K | SEC |
| Sep 15, 2026 | MAETZOLD DEREK J | Executive Officer | Sell | 2,656 | $32.00 | $85K | SEC |
| Sep 15, 2026 | MAETZOLD DEREK J | Executive Officer | Sell | 71 | $32.78 | $2K | SEC |
| Sep 15, 2026 | MAETZOLD DEREK J | Executive Officer | Sell | 83 | $32.78 | $3K | SEC |
In the last 12 months Castle Biosciences Inc insiders made open-market purchases worth about $0 and sales worth about $19.3 million. Data comes from SEC Form 4 filings, updated every 30 minutes on CapitalSnitch.
The most recent open-market insider trade in CSTL was filed on 2026-10-07.
176 investment managers reported holding CSTL in SEC Form 13F filings for Q2 2026.
No congressional trades in CSTL were reported in the past two years. The full list is free on CapitalSnitch.
Public-record data for research and education, not investment advice. Insider sales are often pre-planned (10b5-1). Congress data: Data derived from public disclosures filed under the Ethics in Government Act and the STOCK Act, republished free for public transparency and news reporting. Disclosures may lag the trade by 45 days or more and show amounts only as ranges. This data may not be used for credit rating, loan underwriting, solicitation of money (political, charitable or other), direct-mail or commercial targeting (5 U.S.C. 13107).