Insider selling is trivial in size and likely liquidity-driven. No bearish signal — monitor for any subsequent larger sales or a pattern of sustained insider distribution before adjusting position.
Price Chart
Executive Summary
Two insiders at Castle Biosciences sold a combined $189K in open-market transactions over two days. The CEO's sale was small and paired with a derivative exercise, while the COO's $178K sale is the dominant trade. Relative to the $641M market cap, the cluster is trivial at 0.03% — a routine liquidity event, not a material signal.
Key Financial Metrics
Key Facts
- CEO Derek Maetzold sold 550 shares for $11K on June 15, paired with a derivative exercise of 550 shares at $2.39/share.
- COO Kristen Oelschlager sold 8,587 shares for $178K on June 16 — the largest trade in the cluster.
- Total cluster value of $189K represents ~0.03% of CSTL's $641M market cap.
- No open-market purchases in the cluster; net direction is selling.
Financial Impact
Cluster total of $189K is immaterial at 0.03% of market cap.
Risk Factors
- If the COO continues selling in coming weeks, the pattern could become more informative.
- CEO's derivative exercise and immediate sale is a routine tax-planning move, not a conviction sale.
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-1781856074051 |
Filters
| Type | Now | ||||
|---|---|---|---|---|---|
Oct 21, 2026 5d ago | Insider Cluster | $33.19 $33.08 | ▼ −0.33% | ▲ +0.19% | $33.30 (+0.33%) |
Oct 5, 2026 21d ago | 144 | $33.36 $33.00 | ▼ −1.08% | ▼ −0.84% | $33.30 (−0.18%) |
Oct 5, 2026 21d ago | Insider Cluster | $33.36 $33.00 | ▼ −1.08% | ▼ −0.84% | $33.30 (−0.18%) |
Sep 23, 2026 4w ago | Insider Cluster | $35.19 $35.81 | ▼ −1.76% | ▼ −1.22% | $33.30 (+5.37%) |
Sep 16, 2026 5w ago | Insider Cluster | $36.78 $35.34 | ▼ −3.92% | ▼ −4.04% | $33.30 (−9.46%) |
Sep 11, 2026 6w ago | 144 | $33.44 $35.50 | ▲ +6.16% | ▲ +6.62% | $33.30 (−0.42%) |
Sep 3, 2026 7w ago | Insider Cluster | $32.91 $32.76 | ▲ +0.46% | ▼ −0.09% | $33.30 (−1.19%) |
Sep 2, 2026 7w ago | Insider Cluster | $32.65 $32.91 | ▲ +0.80% | ▲ +1.18% | $33.30 (+1.99%) |
Sep 1, 2026 7w ago | Insider Cluster | $33.42 $32.65 | ▼ −2.30% | ▼ −3.35% | $33.30 (−0.36%) |
Aug 27, 2026 8w ago | Insider Cluster | $33.50 $33.03 | ▼ −1.40% | ▼ −1.10% | $33.30 (−0.60%) |
US Market Status
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