As of April 28, 2026, the three largest insider holders of AMPX are Inc. Amprius, (TenPercentOwner, 2.50Mn shares), Kang Sun (Chief Executive Officer, 1.34Mn shares), Jonathan Bornstein (President Of Amprius Lab, 1.04Mn shares).
| Holder | Position | Shares (Direct) | Shares (Indirect) | Report Date |
|---|---|---|---|---|
| Inc. Amprius, | - | 2,500,071 | 0 | 25 Oct, 2024 |
| Kang Sun | Chief Executive Officer | 1,342,400 | 0 | 02 Apr, 2026 |
| 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 |
| Ricardo C. Rodriguez | Chief Financial Officer | 350,000 | 0 | 13 Mar, 2026 |
| Livingston Satterthwaite | - | 336,083 | 0 | 17 Jun, 2025 |
| Kang Sun | - | 0 | 56,406 | 24 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 |
|---|---|---|---|---|---|---|---|---|
| 01 Apr, 2026 | Kang Sun | Common stock | A | 1,312,505 | $1.78 | 2,654,905 | D | M |
| 01 Apr, 2026 | Kang Sun | Common stock | A | 187,495 | $3.68 | 2,842,400 | D | M |
| 01 Apr, 2026 | Kang Sun | Common stock | D | 1,250,963 | $15.73 | 1,591,437 | D | S |
| 01 Apr, 2026 | Kang Sun | Common stock | D | 249,037 | $16.78 | 1,342,400 | D | S |
| 01 Apr, 2026 | Kang Sun | Stock Option (right to buy) | D | 1,312,505 | $1.78 | 0 | D | M |
| 01 Apr, 2026 | Kang Sun | Stock Option (right to buy) | D | 187,495 | $3.68 | 1,787,007 | D | M |
| 23 Mar, 2026 | Kang Sun | Common stock | D | 152,823 | $18.69 | 121,452 | I | S |
| 23 Mar, 2026 | Kang Sun | Common stock | D | 65,046 | $19.06 | 56,406 | I | S |
| 12 Mar, 2026 | Wen Hsuan Hsieh | Common stock | A | 270,251 | $2.61 | 457,590 | D | M |
| 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 | 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 |
| 04 Mar, 2026 | Ricardo C. Rodriguez | Common stock | A | 150,000 | $0.00 | 350,000 | D | A |
| 04 Mar, 2026 | Constantin Ionel Stefan | Common stock | A | 110,000 | $0.00 | 833,330 | D | A |
| 04 Mar, 2026 | Thomas M Stepien | Common stock | A | 150,000 | $0.00 | 760,000 | D | A |
| 23 Feb, 2026 | Kang Sun | Common stock | D | 61,251 | $10.16 | 1,342,400 | D | S |
| 23 Feb, 2026 | Constantin Ionel Stefan | Common stock | D | 25,366 | $10.16 | 723,330 | D | S |
| 28 Jan, 2026 | Constantin Ionel Stefan | Common stock | A | 90 | $0.62 | 748,786 | D | M |
| 28 Jan, 2026 | Constantin Ionel Stefan | Common stock | A | 39,600 | $0.05 | 788,386 | D | M |