Amprius Technologies, Inc. (AMPX) Insider Trading
Over the last 3 months, AMPX insiders made 0 open-market buys and 7 sales, a net sale of -$3.5M (SEC Form 4). Over the last 6 months, 213 institutions increased and 123 reduced their position (13F).
Insider Activity
Sentiment
0/100
Buys (3m)
0
Sells (3m)
7
Net (3m)
-$3.5M
Insider trades by month Buys Sells
Feb
Mar
Apr
May
Jun
Aug
Context3-month price -50.5%Institutions accumulating (13F)
| Date | Insider | Type | Shares | Price |
|---|---|---|---|---|
| Aug 25, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Sell | 8,000 | $10.03 |
| Aug 25, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Sell | 23,529 | $10.34 |
| Aug 25, 2026 | Stefan Constantin Ionelofficer: Chief Technology Officer | Sell | 29,681 | $10.34 |
| Aug 25, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Grant | 346 | — |
| Aug 25, 2026 | Sun Kangdirector | Sell | 62,101 | $10.34 |
| Jun 16, 2026 | Chu Stevendirector | Grant | 10,423 | — |
| Jun 16, 2026 | DIXON DONALD Rdirector | Sell | 85,000 | $17.17 |
| Jun 16, 2026 | DIXON DONALD Rdirector | Grant | 10,423 | — |
| Jun 16, 2026 | SATTERTHWAITE LIVINGSTONdirector | Grant | 10,423 | — |
| Jun 16, 2026 | BAYLESS KATHLEEN Adirector | Grant | 10,423 | — |
| Jun 11, 2026 | DIXON DONALD Rdirector | Sell | 40,000 | $19.13 |
| Jun 5, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Sell | 2,000 | $20.97 |
| May 28, 2026 | DIXON DONALD Rdirector | Sell | 17,895 | $17.90 |
| May 28, 2026 | Stefan Constantin Ionelofficer: Chief Technology Officer | Sell | 3,208 | $17.19 |
| May 28, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Sell | 4,375 | $17.19 |
| May 28, 2026 | Sun Kangdirector | Sell | 356 | $17.19 |
| May 26, 2026 | Stepien Thomas Mdirector, officer: Chief Executive Officer | Sell | 60,702 | $14.79 |
| May 26, 2026 | Stefan Constantin Ionelofficer: Chief Technology Officer | Sell | 28,812 | $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 | Option | 1,312,505 | $1.78 |
| Apr 2, 2026 | Sun Kangdirector | Sell | 1,250,963 | $15.73 |
| Apr 2, 2026 | Sun Kangdirector | Sell | 249,037 | $16.78 |
| 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 | Option | 270,251 | $2.61 |
| Mar 13, 2026 | HSIEH Wen Hsuandirector | Sell | 130,646 | $18.22 |
Source: AMPX SEC Form 4 filings, latest Aug 25, 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
213
New positions
148
Reduced
123
Sold out
47
Largest moves
| Institution | Action | Shares | Filed |
|---|---|---|---|
| BlackRock, Inc. | Increased | 11.3M | Aug 7, 2026 |
| JANE STREET GROUP, LLC | Increased | 9.3M | Aug 14, 2026 |
| BLACKROCK, INC. | Increased | 9.2M | May 13, 2026 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Increased | 8.2M | Aug 14, 2026 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Increased | 6.6M | May 15, 2026 |
| JANE STREET GROUP, LLC | Increased | 6.6M | May 12, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | Increased | 5.6M | Aug 13, 2026 |
| UBS Group AG | Increased | 5.4M | Aug 13, 2026 |
| CITADEL ADVISORS LLC | Increased | 5.3M | Aug 14, 2026 |
| MORGAN STANLEY | Increased | 5.1M | Aug 13, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | New Position | 4.9M | May 15, 2026 |
| Point72 Asset Management, L.P. | Increased | 4.4M | Aug 14, 2026 |
| TWO SIGMA INVESTMENTS, LP | Increased | 4.3M | Aug 14, 2026 |
| CITADEL ADVISORS LLC | Increased | 4.2M | May 15, 2026 |
| DRIEHAUS CAPITAL MANAGEMENT LLC | Increased | 3.8M | May 15, 2026 |
Source: SEC Form 13F filings. For informational purposes only — not investment advice.