As of March 23, 2026, the three largest insider holders of AMPX are Inc. Amprius, (TenPercentOwner, 2.50Mn shares), Kang Sun (Director, 1.34Mn shares), Justin E Mirro (Director, 1.20Mn shares).
| Holder | Position | Shares (Direct) | Shares (Indirect) | Report Date |
|---|---|---|---|---|
| Inc. Amprius, | 2,500,071 | 0 | 25 Oct, 2024 | |
| Kang Sun | 1,342,400 | 0 | 24 Feb, 2026 | |
| Justin E Mirro | 0 | 1,195,000 | 05 Sep, 2024 | |
| Jonathan Bornstein | President Of Amprius Lab | 0 | 1,040,950 | 22 Nov, 2024 |
| Sandra Wallach | Chief Financial Officer | 1,005,275 | 0 | 25 Aug, 2025 |
| Constantin Ionel Stefan | Chief Technology Officer | 833,330 | 0 | 06 Mar, 2026 |
| Thomas M Stepien | Chief Executive Officer | 760,000 | 0 | 06 Mar, 2026 |
| Jonathan Bornstein | President Of Amprius Lab | 422,668 | 0 | 12 Mar, 2025 |
| Donald R Dixon | 394,656 | 0 | 17 Jun, 2025 | |
| Ricardo C. Rodriguez | Chief Financial Officer | 350,000 | 0 | 13 Mar, 2026 |
| Livingston Satterthwaite | 336,083 | 0 | 17 Jun, 2025 | |
| Kathleen A Bayless | 205,697 | 0 | 17 Jun, 2025 | |
| Mary Gustanski | 146,396 | 0 | 07 Jun, 2024 | |
| Justin E Mirro | 142,895 | 0 | 07 Jun, 2024 | |
| Steven Chu | 127,339 | 0 | 12 Mar, 2026 | |
| Wen Hsuan Hsieh | 44,444 | 0 | 13 Mar, 2026 |
* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.
| Transaction Date | Insider Name | Security Class | Transaction Type | Shares Traded | Price | Shares Remaining | Ownership | Code |
|---|---|---|---|---|---|---|---|---|
| 04 Mar, 2026 | Ricardo C. Rodriguez | Common stock | A | 150,000 | $0.00 | 350,000 | D | A |
| 12 Mar, 2026 | Wen Hsuan Hsieh | Common stock | A | 270,251 | $2.61 | 457,590 | D | M |
| 12 Mar, 2026 | Wen Hsuan Hsieh | Common stock | D | 282,500 | $18.55 | 175,090 | D | S |
| 12 Mar, 2026 | Wen Hsuan Hsieh | Common stock | D | 130,646 | $18.22 | 44,444 | D | S |
| 12 Mar, 2026 | Wen Hsuan Hsieh | Stock Option (right to buy) | D | 270,251 | $2.61 | 0 | D | M |
| 10 Mar, 2026 | Steven Chu | Common stock | A | 104,132 | $0.62 | 293,971 | D | M |
| 10 Mar, 2026 | Steven Chu | Common stock | D | 166,632 | $17.92 | 127,339 | D | S |
| 12 Mar, 2026 | Steven Chu | Common stock | A | 86,143 | $2.61 | 213,482 | D | M |
| 12 Mar, 2026 | Steven Chu | Common stock | A | 69,422 | $0.62 | 282,904 | D | M |
| 12 Mar, 2026 | Steven Chu | Common stock | D | 100,000 | $18.65 | 182,904 | D | S |
| 12 Mar, 2026 | Steven Chu | Common stock | D | 50,000 | $18.21 | 132,904 | D | S |
| 12 Mar, 2026 | Steven Chu | Common stock | D | 5,565 | $18.53 | 127,339 | D | S |
| 10 Mar, 2026 | Steven Chu | Stock Option (right to buy) | D | 104,132 | $0.62 | 69,422 | D | M |
| 12 Mar, 2026 | Steven Chu | Stock Option (right to buy) | D | 86,143 | $2.61 | 184,108 | D | M |
| 12 Mar, 2026 | Steven Chu | Stock Option (right to buy) | D | 69,422 | $0.62 | 0 | D | M |
| 04 Mar, 2026 | Ricardo C. Rodriguez | Common stock | A | 150,000 | $0.00 | 350,000 | D | A |
| 04 Mar, 2026 | Thomas M Stepien | Common stock | A | 150,000 | $0.00 | 760,000 | D | A |
| 04 Mar, 2026 | Constantin Ionel Stefan | Common stock | A | 110,000 | $0.00 | 833,330 | D | A |
| 23 Feb, 2026 | Constantin Ionel Stefan | Common stock | D | 25,366 | $10.16 | 723,330 | D | S |
| 23 Feb, 2026 | Kang Sun | Common stock | D | 61,251 | $10.16 | 1,342,400 | D | S |