No bearish signal from this cluster. The small dollar amount, derivative-exercise pattern, and C-suite-only makeup indicate option-vesting liquidity sales. Monitor for any subsequent change in company guidance or clinical data releases, but on its own this filing is not actionable.
Price Chart
Executive Summary
Three C-suite insiders at Castle Biosciences, including the CEO and COO, sold shares worth a combined ~$240K over a two-day window. The sales represent a very small fraction of the ~$931M market cap (<<0.1%), making them routine in size. The CEO also had derivative exercises at nominal cost during the same period, indicating that the sales are tied to option vesting rather than a directional negative view.
Key Financial Metrics
Key Facts
- Total insider sales of ~$240K (open-market) over two days
- CEO Derek Maetzold sold ~$104K; COO Kristen Oelschlager sold ~$87K; CCO Tobin Juvenal sold ~$49K
- CEO exercised derivatives (2,546 and 10,664 shares at $2.39) concurrently with sales—strongly suggests 10b5-1/vesting-driven transaction
- Sales represent <0.03% of $931M market cap—trivial relative to company size
Financial Impact
~$240K in total insider open-market sales, ~0.03% of market cap—immaterial to company valuation
Risk Factors
- Management selling into strength could signal lack of conviction if sales accelerate or increase in size materially
Market Snapshot
Investment Themes
Documents Analyzed
This report is based on 1 SEC document filed with EDGAR.
| Document | Accession Number |
|---|---|
| CLUSTER Data (Synthetic) | cluster-CSTL-1786082650448 |
Filters
| Type | Now | ||||
|---|---|---|---|---|---|
Oct 21, 2026 6d ago | Insider Cluster | $33.19 $33.08 | ▼ −0.33% | ▲ +0.19% | $34.51 (+3.98%) |
Oct 5, 2026 22d ago | 144 | $33.36 $33.00 | ▼ −1.08% | ▼ −0.84% | $34.51 (+3.45%) |
Oct 5, 2026 22d ago | Insider Cluster | $33.36 $33.00 | ▼ −1.08% | ▼ −0.84% | $34.51 (+3.45%) |
Sep 23, 2026 5w ago | Insider Cluster | $35.19 $35.81 | ▼ −1.76% | ▼ −1.22% | $34.51 (+1.93%) |
Sep 16, 2026 6w ago | Insider Cluster | $36.78 $35.34 | ▼ −3.92% | ▼ −4.04% | $34.51 (−6.17%) |
Sep 11, 2026 6w ago | 144 | $33.44 $35.50 | ▲ +6.16% | ▲ +6.62% | $34.51 (+3.20%) |
Sep 3, 2026 7w ago | Insider Cluster | $32.91 $32.76 | ▲ +0.46% | ▼ −0.09% | $34.51 (−4.86%) |
Sep 2, 2026 7w ago | Insider Cluster | $32.65 $32.91 | ▲ +0.80% | ▲ +1.18% | $34.51 (+5.70%) |
Sep 1, 2026 8w ago | Insider Cluster | $33.42 $32.65 | ▼ −2.30% | ▼ −3.35% | $34.51 (+3.26%) |
Aug 27, 2026 8w ago | Insider Cluster | $33.50 $33.03 | ▼ −1.40% | ▼ −1.10% | $34.51 (+3.01%) |
US Market Status
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