The insider selling is small relative to market cap and likely driven by routine portfolio diversification or tax planning rather than a bearish signal. Monitor for any upcoming material news (e.g., earnings, government contract announcements) that could explain the timing, but the low dollar value and historical underperformance of AMPX calls suggest no immediate trade action.
Price Chart
Executive Summary
A cluster of insider selling at Amprius Technologies saw the CEO, CTO, and a director sell a combined $949K in open-market sales on August 21-24, 2026. The CEO also made non-cash gifts and a grant. The selling follows a recent 8-K extending the Fremont facility lease, and the total value represents ~0.07% of the $1.4B market cap, which is below the 0.1% materiality threshold.
Key Financial Metrics
Key Facts
- CEO Thomas Stepien sold 31,529 shares for ~$323.6K on Aug 21 and 24.
- CTO Stefan Constantin Ionel sold 29,681 shares for ~$306.9K on Aug 21.
- Director Sun Kang sold 62,101 shares for ~$642.2K on Aug 21.
- Total open-market sales: ~$949K, or ~0.07% of the $1.4B market cap.
- CEO also made non-cash transactions: a grant of 346 shares and gifts of 5,346 shares.
- The cluster follows an 8-K (Aug 13) extending the Fremont facility lease by 7 years.
Financial Impact
Total insider sales of ~$949K, representing ~0.07% of market cap — well below the 0.1% materiality threshold for a $1.4B company.
Risk Factors
- Insider selling could accelerate if the stock price rises, but current levels are not alarming.
- The company's high cash burn rate (implied by recent lease extension and lack of profitability) could pressure the stock if not offset by revenue growth.
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-1787728619425 |
Filters
| Type | Now | ||||
|---|---|---|---|---|---|
Oct 9, 2026 17d ago | S-3ASR | $8.87 | awaiting T+60 | — | $8.77 (−1.16%) |
Sep 25, 2026 4w ago | 8-K | $9.60 | awaiting T+60 | — | $8.77 (−8.67%) |
Aug 25, 2026 8w ago | Insider Cluster | $10.20 | awaiting T+60 | — | $8.77 (−14.05%) |
Aug 13, 2026 10w ago | 8-K | $12.51 | awaiting T+60 | — | $8.77 (−29.92%) |
Aug 1, 2026 12w ago | Institutional Cluster | $10.12 | awaiting T+60 | — | $8.77 (+13.37%) |
Jun 11, 2026 19w ago | Insider Cluster | $16.31 $10.39 | ▼ −36.30% | ▼ −39.56% | $8.77 (−46.25%) |
Jun 11, 2026 19w ago | Institutional Cluster | $17.10 $9.89 | ▼ −42.16% | ▼ −46.56% | $8.77 (−48.73%) |
Jun 8, 2026 20w ago | 144 | $4.84 | awaiting T+60 | — | $8.77 (−81.14%) |
May 28, 2026 21w ago | 144 | — | awaiting T+60 | — | — |
May 28, 2026 21w ago | Insider Cluster | $20.28 $9.86 | ▲ +51.38% | ▲ +52.56% | $8.77 (+56.77%) |
US Market Status
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