The dollar amount is trivial relative to market cap, and both sales occurred on the same day at the same price, consistent with a shared blackout-window opening or 10b5-1 plan. Per academic literature, cluster sales are not informative signals. No action warranted.
Price Chart
Executive Summary
CEO and CTO of Amprius Technologies sold a combined $1.32M in open-market sales on May 21, 2026, at ~$14.79/share. The CEO's $898K sale and CTO's $426K sale represent ~0.06% of the $2.3B market cap, a trivial amount that falls well below the 0.1% materiality threshold. This is a routine liquidity-driven cluster with no bearish signal.
Key Financial Metrics
Key Facts
- CEO Stepien Thomas M sold 60,702 shares for $897,685 on May 21, 2026
- CTO Stefan Constantin Ionel sold 28,812 shares for $426,083 on May 21, 2026
- Total insider sales of $1.32M represent ~0.06% of AMPX's $2.3B market cap
- Both sales were open-market transactions at $14.7884/share
- No insider purchases were reported in the cluster window
Financial Impact
Total insider sales of $1.32M, representing 0.06% of market cap — immaterial relative to company size
Risk Factors
- No material risk identified from this cluster given the small dollar value relative to market cap
Market Snapshot
Investment Themes
Documents Analyzed
This report is based on 1 SEC document filed with EDGAR.
| Document | Accession Number |
|---|---|
| CLUSTER Data (Synthetic) | cluster-AMPX-1779837050306 |
Filters
| Type | Now | ||||
|---|---|---|---|---|---|
Oct 9, 2026 17d ago | S-3ASR | $8.87 | awaiting T+60 | — | $8.35 (−5.86%) |
Sep 25, 2026 4w ago | 8-K | $9.60 | awaiting T+60 | — | $8.35 (−13.02%) |
Aug 25, 2026 8w ago | Insider Cluster | $10.20 | awaiting T+60 | — | $8.35 (−18.14%) |
Aug 13, 2026 10w ago | 8-K | $12.51 | awaiting T+60 | — | $8.35 (−33.25%) |
Aug 1, 2026 12w ago | Institutional Cluster | $10.12 | awaiting T+60 | — | $8.35 (+17.49%) |
Jun 11, 2026 19w ago | Insider Cluster | $16.31 $10.39 | ▼ −36.30% | ▼ −39.56% | $8.35 (−48.80%) |
Jun 11, 2026 19w ago | Institutional Cluster | $17.10 $9.89 | ▼ −42.16% | ▼ −46.56% | $8.35 (−51.17%) |
Jun 8, 2026 20w ago | 144 | $4.84 | awaiting T+60 | — | $8.35 (−72.52%) |
May 28, 2026 21w ago | 144 | — | awaiting T+60 | — | — |
May 28, 2026 21w ago | Insider Cluster | $20.28 $9.86 | ▲ +51.38% | ▲ +52.56% | $8.35 (+58.83%) |
US Market Status
Subscribe to SecBot
Get Real-Time SEC Filing Intelligence
Comprehensive SEC filing analysis delivered the moment filings hit EDGAR. Sentiment scoring, impact analysis, and actionable insights for every material event.
Create a free account Live analysis, Telegram alerts, watchlists and the MCP server for subscribers