The cluster of C-suite selling is notable for its concentration among operating executives, but the dollar amounts are small relative to market cap. Monitor for any upcoming clinical data readouts or earnings guidance changes that could explain the timing. If selling accelerates above $2M in the next 30 days, it would breach the 0.2% threshold and warrant a more bearish reassessment.
Price Chart
Executive Summary
Two C-suite insiders at Castle Biosciences sold a combined $498K in open-market transactions over two days, with the COO executing three separate sales totaling $838K and the CCO selling $317K. While the dollar amount is modest relative to the $1.0B market cap (~0.05%), the cluster of senior operating executives selling concurrently warrants attention, especially given the company's strong recent stock performance and 93% analyst bullish consensus.
Key Financial Metrics
Key Facts
- Chief Commercial Officer Juvenal Tobin W sold 9,050 shares at $35.04 for $317,112 on 2026-08-25
- Chief Operating Officer Kristen M Oelschlager sold 24,602 shares across three trades totaling $837,865 on 2026-08-24 and 2026-08-25
- Total insider selling in this cluster: $1.155M across 2 C-suite executives
- Cluster represents approximately 0.12% of $1.0B market cap, below the 0.5% materiality threshold
- Prior 30-day insider activity shows 8 sells totaling $1.4M, indicating continued selling pattern
- 93% of analysts rate the stock as Buy or Strong Buy
Financial Impact
Total insider selling of $1.155M represents ~0.12% of market cap — below materiality thresholds for standalone impact
Risk Factors
- Insider selling may indicate management's view that shares are fairly valued or overvalued at current levels
- Concentrated selling by two senior operating executives could signal operational concerns not yet public
- Continued selling pattern (8 sells in 30 days) may create overhang perception
- No insider buying to offset the selling signal
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-1787900872173 |
Filters
| Type | Now | ||||
|---|---|---|---|---|---|
Oct 21, 2026 5d ago | Insider Cluster | $33.19 $33.08 | ▼ −0.33% | ▲ +0.19% | $34.35 (+3.48%) |
Oct 5, 2026 21d ago | 144 | $33.36 $33.00 | ▼ −1.08% | ▼ −0.84% | $34.35 (+2.95%) |
Oct 5, 2026 21d ago | Insider Cluster | $33.36 $33.00 | ▼ −1.08% | ▼ −0.84% | $34.35 (+2.95%) |
Sep 23, 2026 4w ago | Insider Cluster | $35.19 $35.81 | ▼ −1.76% | ▼ −1.22% | $34.35 (+2.40%) |
Sep 16, 2026 5w ago | Insider Cluster | $36.78 $35.34 | ▼ −3.92% | ▼ −4.04% | $34.35 (−6.62%) |
Sep 11, 2026 6w ago | 144 | $33.44 $35.50 | ▲ +6.16% | ▲ +6.62% | $34.35 (+2.71%) |
Sep 3, 2026 7w ago | Insider Cluster | $32.91 $32.76 | ▲ +0.46% | ▼ −0.09% | $34.35 (−4.36%) |
Sep 2, 2026 7w ago | Insider Cluster | $32.65 $32.91 | ▲ +0.80% | ▲ +1.18% | $34.35 (+5.19%) |
Sep 1, 2026 7w ago | Insider Cluster | $33.42 $32.65 | ▼ −2.30% | ▼ −3.35% | $34.35 (+2.77%) |
Aug 27, 2026 8w ago | Insider Cluster | $33.50 $33.03 | ▼ −1.40% | ▼ −1.10% | $34.35 (+2.52%) |
US Market Status
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