Amprius Technologies (AMPX) stock: insider trades, news & valuation
Heavy sellingShare price and insider trades
Amprius Technologies insider trading at a glance (Oct 9, 2026): in the past 12 months, 0 insiders bought $0 and 6 sold $85.7M of AMPX stock on the open market.
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AMPX insider buying and selling by quarter
Open-market purchases (green, above the line) and sales (red, below), by trade date.
| Quarter | Bought | Purchases | Sold | Sales |
|---|---|---|---|---|
| Q4 2026 | — | 0 | — | 0 |
| Q3 2026 | — | 0 | $1.3M | 4 |
| Q2 2026 | — | 0 | $28.9M | 12 |
| Q1 2026 | — | 0 | $41.9M | 17 |
| Q4 2025 | — | 0 | $13.6M | 4 |
Valuation, profit and volume
Summary
Over the past 12 months, 0 Amprius Technologies, Inc. insiders reported open-market purchases totaling $0, while 6 insiders reported sales totaling $85.7M. 13 of 37 recorded sales were made under pre-scheduled Rule 10b5-1 trading plans, which are usually less informative than discretionary sales.
AMPX earnings: how the stock reacted
Each quarterly results release (SEC 8-K Item 2.02), the trend before it, insider trades in the 30 days before, and the 2-day market reaction. “E” marks releases on the chart above.
| Release | 15 days before | Insiders, 30 days before | Reaction (2 days) | Next 30 days |
|---|---|---|---|---|
| Aug 4, 2026 | -0.4% | None | +15.8%S&P +1.6% | -15.6% |
| May 6, 2026 | +9.1% | None | -24.7%S&P +1.1% | +22.2% |
| Mar 4, 2026 | +16.6% | Sold $880K | +28.0%S&P +0.1% | +7.5% |
| Nov 6, 2025 | +6.8% | None | -2.4%S&P -1.0% | -4.3% |
| Aug 7, 2025 | -3.5% | None | +2.0%S&P +0.7% | -11.8% |
| May 8, 2025 | +8.8% | None | +4.7%S&P +0.6% | +17.4% |
| Mar 20, 2025 | -0.9% | None | +41.4%S&P -0.3% | -31.2% |
| Mar 4, 2025 | -31.0% | None | -11.5%S&P -0.1% | +15.0% |
Most companies bar insiders from trading in the weeks before results, so pre-earnings purchases are rare and often made by directors or under pre-set plans. Past reactions don't predict future ones.
Insider transactions
Open-market purchases and sales.
| Filed | Insider | Type | Shares | Price | Value | Since | Score |
|---|---|---|---|---|---|---|---|
| Aug 25SEC | Kang SunDirector | Sell | 62,1011,218,397 held (−5%) | $10.34 | $642K | -8.7% | — |
| Aug 25SEC | Constantin Ionel StefanCTO | Sell | 29,681771,629 held (−4%) | $10.34 | $307K | -8.7% | — |
| Aug 25SEC | Thomas M StepienCEO | Sell | 23,529602,096 held (−4%) | $10.34 | $243K | -8.7% | — |
| Aug 25SEC | Thomas M StepienCEO | Sell | 8,000594,096 held (−1%) | $10.03 | $80K | -5.9% | — |
| Jun 16SEC | Donald R DixonDirector | Sell | 85,000359,380 held (−19%) | $17.17 | $1.5M | -45.0% | — |
| Jun 11SEC | Donald R DixonDirector | Sell | 40,000444,380 held (−8%) | $19.13 | $765K | -50.7% | — |
| Jun 5SEC | Thomas M StepienCEO | Sell | 2,000625,625 held (−0%) | $20.97 | $42K | -55.0% | — |
| May 28SEC | Donald R DixonDirector | Sell | 17,895484,380 held (−4%) | $17.90 | $320K | -47.3% | — |
| May 28SEC | Thomas M StepienCEO | Sell | 4,375694,923 held (−1%) | $17.19 | $75K | -45.1% | — |
| May 28SEC | Constantin Ionel StefanCTO | Sell | 3,208801,310 held (−0%) | $17.19 | $55K | -45.1% | — |
| May 28SEC | Kang SunDirector | Sell | 3561,280,498 held (−0%) | $17.19 | $6K | -45.1% | — |
| May 26SEC | Kang SunDirector | Sell | 67,7961,280,854 held (−5%) | $14.79 | $1.0M | -36.2% | — |
| May 26SEC | Thomas M StepienCEO | Sell | 60,702699,298 held (−8%) | $14.79 | $898K | -36.2% | — |
| May 26SEC | Constantin Ionel StefanCTO | Sell | 28,812804,518 held (−3%) | $14.79 | $426K | -36.2% | — |
| Apr 2SEC | Kang SunDirector | Sell Plan | 1,250,9631,591,437 held (−44%) | $15.73 | $19.7M | -40.0% | — |
| Apr 2SEC | Kang SunDirector | Sell Plan | 249,0371,342,400 held (−16%) | $16.78 | $4.2M | -43.7% | — |
| Mar 24SEC | Kang SunDirector | Sell Plan | 152,823121,452 held (−56%) | $18.69 | $2.9M | -49.5% | — |
| Mar 24SEC | Kang SunDirector | Sell Plan | 65,04656,406 held (−54%) | $19.06 | $1.2M | -50.5% | — |
| Mar 13SEC | Wen Hsuan HsiehDirector | Sell | 282,500175,090 held (−62%) | $18.55 | $5.2M | -49.1% | — |
| Mar 13SEC | Wen Hsuan HsiehDirector | Sell | 130,64644,444 held (−75%) | $18.22 | $2.4M | -48.2% | — |
| Mar 12SEC | Steven ChuDirector | Sell | 166,632127,339 held (−57%) | $17.92 | $3.0M | -47.3% | — |
| Mar 12SEC | Steven ChuDirector | Sell | 100,000182,904 held (−35%) | $18.65 | $1.9M | -49.4% | — |
| Mar 12SEC | Steven ChuDirector | Sell | 50,000132,904 held (−27%) | $18.21 | $910K | -48.2% | — |
| Mar 12SEC | Steven ChuDirector | Sell | 5,565127,339 held (−4%) | $18.53 | $103K | -49.1% | — |
| Feb 24SEC | Kang SunDirector | Sell | 61,2511,342,400 held (−4%) | $10.16 | $622K | -7.1% | — |
| Feb 24SEC | Constantin Ionel StefanCTO | Sell | 25,366723,330 held (−3%) | $10.16 | $258K | -7.1% | — |
| Jan 30SEC | Constantin Ionel StefanCTO | Sell Plan | 39,690748,696 held (−5%) | $12.00 | $476K | -21.3% | — |
| Jan 23SEC | Constantin Ionel StefanCTO | Sell Plan | 492,827748,696 held (−40%) | $12.04 | $5.9M | -21.6% | — |
| Jan 23SEC | Constantin Ionel StefanCTO | Sell Plan | 73,280748,696 held (−9%) | $12.00 | $879K | -21.3% | — |
| Jan 23SEC | Constantin Ionel StefanCTO | Sell Plan | 1,600748,696 held (−0%) | $12.00 | $19K | -21.3% | — |
| Jan 20SEC | Kang SunDirector | Sell Plan | 950,5481,403,651 held (−40%) | $11.07 | $10.5M | -14.7% | — |
| Jan 20SEC | Kang SunDirector | Sell Plan | 43,1851,403,651 held (−3%) | $11.03 | $476K | -14.4% | — |
| Jan 14SEC | Kang SunDirector | Sell Plan | 506,2671,403,651 held (−27%) | $10.10 | $5.1M | -6.5% | — |
| Dec 15SEC | Constantin Ionel StefanCTO | Sell Plan | 198,255748,696 held (−21%) | $10.51 | $2.1M | -10.2% | — |
| Nov 25SEC | Kang SunCEO | Sell | 68,6551,403,651 held (−5%) | $10.08 | $692K | -6.3% | — |
| Nov 25SEC | Constantin Ionel StefanCTO | Sell | 25,024821,951 held (−3%) | $10.08 | $252K | -6.3% | — |
| Nov 19SEC | Kang SunCEO | Sell Plan | 1,000,0001,472,306 held (−40%) | $10.60 | $10.6M | -10.9% | — |
Insiders at Amprius Technologies, Inc.
| Insider | Bought | Sold | Last filing | Score |
|---|---|---|---|---|
| Kang SunDirector | — | $57.6M | Aug 25, 2026 | — |
| Constantin Ionel StefanCTO | — | $10.7M | Aug 25, 2026 | — |
| Wen Hsuan HsiehDirector | — | $7.6M | Mar 13, 2026 | — |
| Steven ChuDirector | — | $5.9M | Mar 12, 2026 | — |
| Donald R DixonDirector | — | $2.5M | Jun 16, 2026 | — |
| Thomas M StepienCEO | — | $1.3M | Aug 25, 2026 | — |
AMPX stock: common questions
Are Amprius Technologies, Inc. insiders buying AMPX stock?
In the past 12 months, 0 insiders reported open-market purchases of AMPX worth $0.
Are Amprius Technologies, Inc. insiders selling AMPX stock?
6 insiders reported sales worth $85.7M over the same period.
Where does this data come from?
Every transaction comes from Form 4 filings that insiders must submit to the SEC within two business days of a trade. We pull them from SEC EDGAR every night.
What is AMPX's 52-week range?
Over the past year AMPX has traded between $7.83 and $22.91. It last closed at $9.44 on Oct 9, 2026.