Amprius Technologies, Inc. (AMPX) Insider Trading
Over the last 3 months, AMPX insiders made 0 open-market buys and 17 sales, a net sale of -$44.2M (SEC Form 4). Over the last 6 months, 200 institutions increased and 107 reduced their position (13F).
Insider Activity
Sentiment
0/100
Buys (3m)
0
Sells (3m)
17
Net (3m)
-$44.2M
Insider trades by month Buys Sells
Dec
Jan
Feb
Mar
Apr
May
Context3-month price +51.4%Institutions accumulating (13F)
| Date | Insider | Type | Shares | Price |
|---|---|---|---|---|
| May 28, 2026 | Stefan Constantin Ionelofficer: Chief Technology Officer | Sell | 3,208 | $17.19 |
| May 28, 2026 | DIXON DONALD Rdirector | Sell | 17,895 | $17.90 |
| May 28, 2026 | Sun Kangdirector | Sell | 356 | $17.19 |
| May 28, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Sell | 4,375 | $17.19 |
| May 26, 2026 | Stefan Constantin Ionelofficer: Chief Technology Officer | Sell | 28,812 | $14.79 |
| May 26, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Sell | 60,702 | $14.79 |
| May 26, 2026 | Sun Kangdirector | Sell | 67,796 | $14.79 |
| May 7, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Grant | 200,000 | — |
| May 7, 2026 | Sun Kangdirector | Grant | 6,250 | — |
| Apr 2, 2026 | Sun Kangdirector | Option | 187,495 | $3.68 |
| Apr 2, 2026 | Sun Kangdirector | Sell | 249,037 | $16.78 |
| Apr 2, 2026 | Sun Kangdirector | Sell | 1,250,963 | $15.73 |
| Apr 2, 2026 | Sun Kangdirector | Option | 1,312,505 | $1.78 |
| Mar 24, 2026 | Sun Kangdirector | Sell | 65,046 | $19.06 |
| Mar 24, 2026 | Sun Kangdirector | Sell | 152,823 | $18.69 |
| Mar 13, 2026 | HSIEH Wen Hsuandirector | Sell | 282,500 | $18.55 |
| Mar 13, 2026 | HSIEH Wen Hsuandirector | Sell | 130,646 | $18.22 |
| Mar 13, 2026 | HSIEH Wen Hsuandirector | Option | 270,251 | $2.61 |
| Mar 12, 2026 | Chu Stevendirector | Sell | 100,000 | $18.65 |
| Mar 12, 2026 | Chu Stevendirector | Sell | 50,000 | $18.21 |
| Mar 12, 2026 | Chu Stevendirector | Sell | 5,565 | $18.53 |
| Mar 12, 2026 | Chu Stevendirector | Sell | 166,632 | $17.92 |
| Mar 12, 2026 | Chu Stevendirector | Option | 104,132 | $0.62 |
| Mar 12, 2026 | Chu Stevendirector | Option | 86,143 | $2.61 |
| Mar 12, 2026 | Chu Stevendirector | Option | 69,422 | $0.62 |
| Mar 6, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Grant | 150,000 | — |
| Mar 6, 2026 | RODRIGUEZ RICARDO C.officer: Chief Financial Officer | Grant | 150,000 | — |
| Mar 6, 2026 | Stefan Constantin Ionelofficer: Chief Technology Officer | Grant | 110,000 | — |
| Feb 24, 2026 | Sun Kangdirector | Sell | 61,251 | $10.16 |
| Feb 24, 2026 | Stefan Constantin Ionelofficer: Chief Technology Officer | Sell | 25,366 | $10.16 |
Source: AMPX SEC Form 4 filings, latest May 28, 2026. For informational purposes only — not investment advice.
Institutional activity (13F)
How institutions changed their AMPX positions over the last 6 months (SEC Form 13F).
Increased
200
New positions
118
Reduced
107
Sold out
61
Largest moves
| Institution | Action | Shares | Filed |
|---|---|---|---|
| BLACKROCK, INC. | Increased | 9.2M | May 13, 2026 |
| BLACKROCK, INC. | Increased | 8.8M | Feb 12, 2026 |
| VANGUARD GROUP INC | Increased | 7.1M | Jan 29, 2026 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Increased | 5.2M | May 15, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | New Position | 4.9M | May 15, 2026 |
| JANE STREET GROUP, LLC | Increased | 4.2M | May 12, 2026 |
| DRIEHAUS CAPITAL MANAGEMENT LLC | Increased | 3.8M | May 15, 2026 |
| TWO SIGMA INVESTMENTS, LP | Increased | 3.5M | May 15, 2026 |
| MORGAN STANLEY | Increased | 3.2M | May 15, 2026 |
| GEODE CAPITAL MANAGEMENT, LLC | Increased | 2.8M | May 15, 2026 |
| MORGAN STANLEY | Increased | 2.8M | Feb 13, 2026 |
| STATE STREET CORP | Increased | 2.7M | May 15, 2026 |
| GEODE CAPITAL MANAGEMENT, LLC | Increased | 2.7M | Feb 9, 2026 |
| STATE STREET CORP | Increased | 2.6M | Feb 13, 2026 |
| DRIEHAUS CAPITAL MANAGEMENT LLC | Reduced | 2.4M | Feb 17, 2026 |
Source: SEC Form 13F filings. For informational purposes only — not investment advice.