🕵️ Amprius Technologies, Inc. ($AMPX)
SEC insider & ownership activity, last 12 months · CIK 1899287 · every row links its SEC filing
Over the last 12 months insiders sold $85.2M with no open-market buying against it. Sun Kang sold $57.4M (Aug–May). 3 planned sales are pending, the largest $1.0M (Kang Sun). No red-flag 8-Ks in the window.
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Monthly net open-market insider flow, last 12 months (up = net buying)
Insider flow
0 buyers, $0 (0 lots) · 7 sellers, $85.2M (36 lots)
| Insider | Buys | Bought | Sells | Sold | Last |
|---|---|---|---|---|---|
| Sun Kang | 0 | – | 13 | $57.4M | May 27, 2026 |
| Stefan Constantin Ionel | 0 | – | 10 | $10.5M | May 27, 2026 |
| Hsieh Wen Hsuan | 0 | – | 2 | $7.6M | Mar 12, 2026 |
| Chu Steven | 0 | – | 4 | $5.9M | Mar 12, 2026 |
| Donald R. Dixon | 0 | – | 3 | $2.5M | Jun 15, 2026 |
| Thomas M Stepien | 0 | – | 3 | $1.0M | Jun 4, 2026 |
| Sandra Wallach | 0 | – | 1 | $194K | Aug 21, 2025 |
5%+ holders
| Holder | Stake | Class | Schedule | Event | |
|---|---|---|---|---|---|
| Blackrock, Inc. | 7.4% | 13G | Jul 27, 2026 | filing ↗ | |
| JANE Street Group, LLC | 5.1% | 13G | Apr 28, 2026 | filing ↗ |
Planned insider sales (Form 144)
| Seller | Planned | Approx. sale date | |
|---|---|---|---|
| Donald R. Dixon | $2.4M | Jun 8, 2026 | filing ↗ |
| Thomas M Stepien | $42K | Jun 4, 2026 | filing ↗ |
| Thomas M. Stepien | $75K | May 27, 2026 | filing ↗ |
| Constantin Ionel Stefan | $55K | May 27, 2026 | filing ↗ |
| Kang Sun | $6K | May 27, 2026 | filing ↗ |
| Donald R. Dixon | $316K | May 26, 2026 | filing ↗ |
| Thomas M. Stepien | $898K | May 21, 2026 | filing ↗ |
| Stefan Constantin Ionel | $426K | May 21, 2026 | filing ↗ |
| Kang Sun | $1.0M | May 21, 2026 | filing ↗ |
| Kang Sun | $25.3M | Apr 1, 2026 | filing ↗ |
| Kang Sun | $3.5M | Mar 23, 2026 | filing ↗ |
| Steven Chu | $2.9M | Mar 12, 2026 | filing ↗ |
| Wen Hsuan Hsieh | $7.6M | Mar 12, 2026 | filing ↗ |
| Steven Chu | $3.0M | Mar 10, 2026 | filing ↗ |
| Stefan Constantin Ionel | $258K | Feb 23, 2026 | filing ↗ |
| Kang Sun | $622K | Feb 23, 2026 | filing ↗ |
| Stefan Constantin Ionel | $8.0M | Jan 21, 2026 | filing ↗ |
| Kang Sun | $10.3M | Jan 16, 2026 | filing ↗ |
| Kang Sun | $4.8M | Jan 12, 2026 | filing ↗ |
| Stefan Constantin Ionel | $2.2M | Dec 11, 2025 | filing ↗ |
| Stefan Constantin Ionel | $252K | Nov 21, 2025 | filing ↗ |
| Kang Sun | $692K | Nov 21, 2025 | filing ↗ |
| Kang Sun | $11.3M | Nov 17, 2025 | filing ↗ |
| Stefan Constantin Ionel | $131K | Aug 21, 2025 | filing ↗ |
| Sandra Wallach | $194K | Aug 21, 2025 | filing ↗ |
| Kang Sun | $448K | Aug 21, 2025 | filing ↗ |
Material events (8-K)
| Item | Event date | |
|---|---|---|
| Shareholder vote (5.07) | Jun 11, 2026 | filing ↗ |
| Unregistered equity sale (3.02) | May 6, 2026 | filing ↗ |
| Material agreement (1.01) | May 6, 2026 | filing ↗ |
| Unregistered equity sale (3.02) | May 6, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | May 6, 2026 | filing ↗ |
| Earnings (2.02) | May 6, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | May 6, 2026 | filing ↗ |
| Auditor change (4.01) | Apr 17, 2026 | filing ↗ |
| Earnings (2.02) | Mar 4, 2026 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Mar 4, 2026 | filing ↗ |
| Agreement terminated (1.02) | Jan 30, 2026 | filing ↗ |
| Other events (8.01) | Jan 12, 2026 | filing ↗ |
| Officer/director changes (5.02) | Dec 18, 2025 | filing ↗ |
| Earnings (2.02) | Nov 6, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Nov 6, 2025 | filing ↗ |
| Officer/director changes (5.02) | Oct 6, 2025 | filing ↗ |
| Officer/director changes (5.02) | Sep 2, 2025 | filing ↗ |
| Earnings (2.02) | Aug 7, 2025 | filing ↗ |
| Financial Statements and Exhibits (9.01) | Aug 7, 2025 | filing ↗ |