Amprius Technologies, Inc. — Insider Transactions
Form 4 filings by directors, officers, and 10%+ shareholders
SEC rules require corporate insiders — including directors, executive officers, and any shareholder owning more than 10% of a company's shares — to report changes in their ownership within two business days of a transaction. These disclosures are filed as Form 4. Open-market purchases (code P) are generally considered the most meaningful signal, as insiders are spending their own money.
| Insider | Title | Type | Shares | Price | Value | Owns After | Date |
|---|---|---|---|---|---|---|---|
| Stepien Thomas M | President | Award / Grant | 200,000 | — | — | 610,000 | Dec 19, 2025 |
| Stefan Constantin Ionel | Chief Technology Officer | Sale | 198,255 | $10.51 | $2,083,660 | 748,696 | Dec 11, 2025 |
| Stefan Constantin Ionel | Chief Technology Officer | Sale | 25,024 | $10.08 | $252,242 | 821,951 | Nov 21, 2025 |
| Sun Kang | Chief Executive Officer | Sale | 68,655 | $10.08 | $692,042 | 1,403,651 | Nov 21, 2025 |
| Sun Kang | Chief Executive Officer | Sale | 1,000,000 | $10.60 | $10,600,000 | 1,472,306 | Nov 17, 2025 |
| RODRIGUEZ RICARDO C. | Chief Financial Officer | Award / Grant | 200,000 | — | — | 200,000 | Oct 6, 2025 |
| Stefan Constantin Ionel | Chief Technology Officer | Sale | 19,159 | $6.82 | $130,664 | 846,975 | Aug 21, 2025 |
| Wallach Sandra | Chief Financial Officer | Sale | 28,390 | $6.82 | $193,620 | 1,005,275 | Aug 21, 2025 |
| Sun Kang | Chief Executive Officer | Sale | 65,654 | $6.82 | $447,760 | 1,472,306 | Aug 21, 2025 |
| HSIEH Wen Hsuan | — | Award / Grant | 44,444 | — | — | 187,339 | Jun 13, 2025 |
| DIXON DONALD R | — | Award / Grant | 44,444 | — | — | 394,656 | Jun 13, 2025 |
| SATTERTHWAITE LIVINGSTON | — | Award / Grant | 44,444 | — | — | 336,083 | Jun 13, 2025 |
| BAYLESS KATHLEEN A | — | Award / Grant | 44,444 | — | — | 205,697 | Jun 13, 2025 |
| Chu Steven | — | Award / Grant | 44,444 | — | — | 189,839 | Jun 13, 2025 |
| Stefan Constantin Ionel | Chief Technology Officer | Sale | 20,366 | $2.43 | $49,489 | 866,134 | May 21, 2025 |
| Wallach Sandra | Chief Financial Officer | Sale | 27,595 | $2.43 | $67,056 | 1,033,665 | May 21, 2025 |
| Sun Kang | Chief Executive Officer | Sale | 69,786 | $2.43 | $169,580 | 1,812,235 | May 21, 2025 |
| Stepien Thomas M | President | Award / Grant | 400,000 | — | — | 400,000 | May 1, 2025 |
| Sun Kang | Chief Executive Officer | Award / Grant | 599,400 | — | — | 1,882,021 | Mar 19, 2025 |
| Wallach Sandra | Chief Financial Officer | Award / Grant | 383,260 | — | — | 1,061,260 | Mar 19, 2025 |
| Stefan Constantin Ionel | Chief Technology Officer | Award / Grant | 461,540 | — | — | 886,500 | Mar 19, 2025 |
| Stefan Constantin Ionel | Chief Technology Officer | Option Exercise | 3,471 | $0.98 | $3,402 | 424,960 | Mar 14, 2025 |
| Bornstein Jonathan | President of Amprius Lab | Option Exercise | 3,471 | $0.98 | $3,402 | 422,668 | Mar 10, 2025 |
| Sun Kang | Chief Executive Officer | Sale | 34,353 | $3.13 | $107,525 | 1,282,621 | Feb 21, 2025 |
| Wallach Sandra | Chief Financial Officer | Sale | 18,142 | $3.13 | $56,784 | 678,000 | Feb 21, 2025 |
| Stefan Constantin Ionel | Chief Technology Officer | Sale | 9,066 | $3.13 | $28,377 | 421,489 | Feb 21, 2025 |
| Bornstein Jonathan | President of Amprius Lab | Sale | 13,527 | $3.13 | $42,340 | 419,197 | Feb 21, 2025 |
| Sun Kang | Chief Executive Officer | Sale | 33,779 | $1.96 | $66,207 | 1,316,974 | Nov 21, 2024 |
| Bornstein Jonathan | President of Amprius Lab | Sale | 133,536 | $1.92 | $256,389 | 1,039,187 | Nov 21, 2024 |
| Wallach Sandra | Chief Financial Officer | Sale | 17,158 | $1.96 | $33,630 | 696,142 | Nov 21, 2024 |
| Stefan Constantin Ionel | Chief Technology Officer | Sale | 8,575 | $1.96 | $16,807 | 430,555 | Nov 21, 2024 |
| Amprius, Inc. | — | Other | 5,500,000 | — | — | 59,695,997 | Oct 23, 2024 |
| MIRRO JUSTIN E | — | Sale | 140,000 | $0.81 | $113,400 | 1,195,000 | Sep 3, 2024 |
| Amprius, Inc. | — | Sale | 13,255 | $0.95 | $12,592 | 65,195,997 | Sep 3, 2024 |
| Wallach Sandra | Chief Financial Officer | Sale | 17,606 | $1.04 | $18,310 | 713,300 | Aug 21, 2024 |
| Bornstein Jonathan | President of Amprius Lab | Sale | 18,644 | $1.04 | $19,390 | 1,528,251 | Aug 21, 2024 |
| Sun Kang | Chief Executive Officer | Sale | 33,333 | $1.04 | $34,666 | 1,350,753 | Aug 21, 2024 |
| Stefan Constantin Ionel | Chief Technology Officer | Sale | 8,800 | $1.04 | $9,152 | 386,168 | Aug 21, 2024 |
| SATTERTHWAITE LIVINGSTON | — | Award / Grant | 283,019 | — | — | 291,639 | Aug 13, 2024 |
| MIRRO JUSTIN E | — | Award / Grant | 925,900 | — | — | 2,393,042 | Jul 23, 2024 |
| MIRRO JUSTIN E | — | Sale | 65,000 | $1.22 | $79,300 | 1,650,000 | Jun 12, 2024 |
| HSIEH Wen Hsuan | — | Award / Grant | 125,000 | — | — | 142,895 | Jun 7, 2024 |
| BAYLESS KATHLEEN A | — | Award / Grant | 125,000 | — | — | 161,253 | Jun 7, 2024 |
| Chu Steven | — | Award / Grant | 125,000 | — | — | 145,395 | Jun 7, 2024 |
| Gustanski Mary | — | Award / Grant | 114,583 | — | — | 146,396 | Jun 7, 2024 |
| MIRRO JUSTIN E | — | Award / Grant | 125,000 | — | — | 142,895 | Jun 7, 2024 |
| DIXON DONALD R | — | Award / Grant | 125,000 | — | — | 142,895 | Jun 7, 2024 |
| Stefan Constantin Ionel | Chief Technology Officer | Sale | 5,272 | $1.33 | $7,012 | 399,089 | May 22, 2024 |
| Sun Kang | See Remarks | Sale | 19,973 | $1.33 | $26,564 | 1,399,697 | May 22, 2024 |
| Bornstein Jonathan | President of Amprius Lab | Sale | 11,171 | $1.33 | $14,857 | 1,555,626 | May 22, 2024 |