Monitor for further insider selling or commentary around earnings or guidance; CEO selling at this level may signal reduced confidence, especially if not part of a pre-arranged 10b5-1 plan. Consider pairing with short interest and volume trends.
Price Chart
Executive Summary
Castle Biosciences CEO Derek Maetzold sold 49,953 shares in the past week through open-market transactions, totaling approximately $1.3 million. This represents a notable insider selling cluster, though still under 0.2% of the company's $762M market cap.
Key Financial Metrics
Key Facts
- CEO Derek Maetzold sold 49,953 shares over four days (March 13–18, 2026) in open-market transactions.
- Total proceeds from the sales amount to $1,389,146.026.
- All transactions were reported as open-market sales (Form 4 code 'S').
- Total value represents approximately 0.18% of CSTL's $762M market cap.
- No insider purchases were reported in this cluster.
Financial Impact
$1.39 million in insider sales over 7 days
Risk Factors
- Sustained insider selling could erode investor confidence.
- Potential perception of negative sentiment if sales are not part of a pre-planned trading arrangement.
Market Snapshot
Investment Themes
Documents Analyzed
This report is based on 1 SEC document filed with EDGAR.
| Document | Accession Number |
|---|---|
| CONTEXT: Insider Cluster Data (4 trades, 7d window) | cluster-CSTL-1773951720025 |
Filters
| Type | Now | ||||
|---|---|---|---|---|---|
Oct 21, 2026 5d ago | Insider Cluster | $33.19 $33.08 | ▼ −0.33% | ▲ +0.19% | $34.07 (+2.65%) |
Oct 5, 2026 21d ago | 144 | $33.36 $33.00 | ▼ −1.08% | ▼ −0.84% | $34.07 (+2.13%) |
Oct 5, 2026 21d ago | Insider Cluster | $33.36 $33.00 | ▼ −1.08% | ▼ −0.84% | $34.07 (+2.13%) |
Sep 23, 2026 4w ago | Insider Cluster | $35.19 $35.81 | ▼ −1.76% | ▼ −1.22% | $34.07 (+3.18%) |
Sep 16, 2026 5w ago | Insider Cluster | $36.78 $35.34 | ▼ −3.92% | ▼ −4.04% | $34.07 (−7.37%) |
Sep 11, 2026 6w ago | 144 | $33.44 $35.50 | ▲ +6.16% | ▲ +6.62% | $34.07 (+1.88%) |
Sep 3, 2026 7w ago | Insider Cluster | $32.91 $32.76 | ▲ +0.46% | ▼ −0.09% | $34.07 (−3.52%) |
Sep 2, 2026 7w ago | Insider Cluster | $32.65 $32.91 | ▲ +0.80% | ▲ +1.18% | $34.07 (+4.35%) |
Sep 1, 2026 7w ago | Insider Cluster | $33.42 $32.65 | ▼ −2.30% | ▼ −3.35% | $34.07 (+1.94%) |
Aug 27, 2026 8w ago | Insider Cluster | $33.50 $33.03 | ▼ −1.40% | ▼ −1.10% | $34.07 (+1.70%) |
US Market Status
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