Quick Takeaways
- AMPX - Amprius Technologies, Inc. has 25 insiders with reported activity on this page.
- Net insider value flow over the last year: -$80,414,128.
- Recent transaction rows are available for direct filing-level review.
- Info
- Insider Trading
- Financials
- Holders
Insider Transactions Reported by 25 Insiders of Amprius Technologies, Inc.
- Symbol
- AMPX, AMPX-WT on NYSE
- Location
- Fremont, CA
What Changed
- Buy value: ; sell value: $80,414,127.
- Net share flow: -6,170,110.
Why This Matters
- This page gives a plain-language issuer insider context before you inspect transaction-level evidence.
- Use the filing links below to verify timestamps, codes, and ownership impacts directly from SEC forms.
Official SEC Source
Insider trading overview
Last 12 monthsNet insider flow leans to selling over the last 12 months. Net value: -$80,414,128.
Buys
$0
Shares: 0
Insiders: 0
Sells
$80,414,128
Shares: 6,170,110
Insiders: 5
Net
-$80,414,128
Shares: -6,170,110
Insiders: -5
| Window (months) | Buy shares | Sell shares | Buy $ | Sell $ | Net $ |
|---|---|---|---|---|---|
| 0-3 | 0 | 4,140,959 | $0 | $60,621,590 | -$60,621,590 |
| 3-6 | 0 | 1,798,201 | $0 | $18,734,563 | -$18,734,563 |
| 6-9 | 0 | 113,203 | $0 | $771,614 | -$771,614 |
| 9-12 | 0 | 117,747 | $0 | $286,361 | -$286,361 |
Amprius Technologies, Inc. executives and other stock owners filed with the SEC include:
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Kang Sun | Director | $22,974,407 | -$56,589,230 | -71% | Mixed | 01 Apr 2026 |
| Constantin Ionel Stefan | Chief Technology Officer | $9,624,961 | -$10,080,258 | -51% | Mixed | 04 Mar 2026 |
| Thomas M. Stepien | Chief Executive Officer, Director | $8,778,000 | Mixed | 04 Mar 2026 | ||
| Sandra Wallach | Chief Financial Officer | $6,852,155 | -$260,623 | -3.7% | Filing P/S | 21 Aug 2025 |
| Ricardo C. Rodriguez | Chief Financial Officer | $4,042,500 | Mixed | 04 Mar 2026 | ||
| Steven Chu | Director | $2,360,177 | -$5,863,984 | -71% | Filing P/S | 10 Mar 2026 |
| Amprius, Inc. | 10%+ Owner | $2,012,807 | Mixed | 23 Oct 2024 | ||
| Donald R. Dixon | Director | $1,945,266 | Mixed | 13 Jun 2025 | ||
| Justin E. Mirro | Director | $1,077,140 | Mixed | 03 Sep 2024 | ||
| Livingston Satterthwaite | Director | $846,929 | Mixed | 13 Jun 2025 | ||
| Wen Hsuan Hsieh | Director | $809,911 | -$7,620,033 | -90% | Filing P/S | 12 Mar 2026 |
| Kathleen A. Bayless | Director | $518,356 | Mixed | 13 Jun 2025 | ||
| Jonathan Bornstein | President of Amprius Lab | $414,215 | Mixed | 10 Mar 2025 | ||
| Mary E. Gustanski | Director | $198,513 | Mixed | 07 Jun 2024 | ||
| Kensington Capital Sponsor IV LLC | Other* | Mixed | 14 Sep 2022 | |||
| Robert J. Remenar Under Power | Chief Operating Officer | Mixed | 01 Mar 2022 | |||
| Thomas William LaSorda | Director | Mixed | 01 Mar 2022 | |||
| Donald L. Runkle | Director | Mixed | 01 Mar 2022 | |||
| Matthew J. Simoncini | Director | Mixed | 01 Mar 2022 | |||
| Mitchell I. Quain | Director | Mixed | 01 Mar 2022 | |||
| Nicole Nason | Director | Mixed | 01 Mar 2022 | |||
| Dieter Zetsche | Vice Chairman and President | Mixed | 01 Mar 2022 | |||
| Anders Pettersson | Director | Mixed | 01 Mar 2022 | |||
| Simon Boag | Chief Technology Officer | Mixed | 01 Mar 2022 | |||
| Daniel Elliot Huber | Chief Financial Officer | Mixed | 01 Mar 2022 |
Top shareholders of Amprius Technologies, Inc. (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Ownership % is shown only when it is directly reported or safely comparable across share classes.
Methodology: rows are grouped by holder and ranked by the holder's primary source value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
| Holder | Source | Role / Reporting | Ownership % | Shares | Holdings Value | 12M Net Δ | As of | Details |
|---|---|---|---|---|---|---|---|---|
| BlackRock, Inc. |
13D/G
13F
|
Company |
5.8%
|
7,297,002
|
$76,764,461 | $0 | 30 Sep 2025 | |
| VANGUARD GROUP INC |
13F
|
Company |
5.7%
|
7,128,657
|
$56,245,105 | — | 31 Dec 2025 | |
| Kang Sun |
3/4/5
|
Director |
—
mixed-class rows
|
3,185,813
mixed-class rows
|
$22,974,407 | -$56,589,230 | 01 Apr 2026 | |
| MORGAN STANLEY |
13F
|
Company |
2.2%
|
2,809,821
|
$22,169,489 | — | 31 Dec 2025 | |
| GEODE CAPITAL MANAGEMENT, LLC |
13F
|
Company |
2.1%
|
2,678,417
|
$21,136,655 | — | 31 Dec 2025 | |
| STATE STREET CORP |
13F
|
Company |
2%
|
2,553,710
|
$20,148,772 | — | 31 Dec 2025 | |
| Alan E. Salzman |
13D/G
|
SALZMAN ALAN E |
2.6%
|
3,112,992
|
$20,047,668 | $0 | 06 Aug 2025 | |
| DRIEHAUS CAPITAL MANAGEMENT LLC |
13F
|
Company |
1.9%
|
2,393,212
|
$18,882,443 | — | 31 Dec 2025 | |
| GOLDMAN SACHS GROUP INC |
13F
|
Company |
1.8%
|
2,194,841
|
$17,317,295 | — | 31 Dec 2025 | |
| UBS Group AG |
13F
|
Company |
1.7%
|
2,098,946
|
$16,560,684 | — | 31 Dec 2025 | |
| DEUTSCHE BANK AG\ |
13F
|
Company |
1.6%
|
1,955,018
|
$15,425,092 | — | 31 Dec 2025 | |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP |
13F
|
Company |
1.4%
|
1,691,500
|
$13,345,935 | — | 31 Dec 2025 | |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC |
13F
|
Company |
1.3%
|
1,602,001
|
$12,639,788 | — | 31 Dec 2025 | |
| Stephens Investment Management Group LLC |
13F
|
Company |
1.2%
|
1,441,698
|
$11,374,997 | — | 31 Dec 2025 | |
| TWO SIGMA INVESTMENTS, LP |
13F
|
Company |
1.1%
|
1,436,939
|
$11,337,449 | — | 31 Dec 2025 | |
| Invesco Ltd. |
13F
|
Company |
1%
|
1,311,915
|
$10,351,010 | — | 31 Dec 2025 | |
| NORGES BANK |
13F
|
Company |
1%
|
1,304,838
|
$10,295,172 | — | 31 Dec 2025 | |
| Constantin Ionel Stefan |
3/4/5
|
Chief Technology Officer |
0.67%
|
833,330
|
$9,624,961 | -$10,080,258 | 04 Mar 2026 | |
| Thomas M. Stepien |
3/4/5
|
Chief Executive Officer, Director |
0.61%
|
760,000
|
$8,778,000 | — | 04 Mar 2026 | |
| Hudson Bay Capital Management LP |
13F
|
Company |
0.88%
|
1,100,000
|
$8,679,000 | — | 31 Dec 2025 | |
| MILLENNIUM MANAGEMENT LLC |
13F
|
Company |
0.87%
|
1,085,270
|
$8,562,780 | — | 31 Dec 2025 | |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC |
13F
|
Company |
0.83%
|
1,036,891
|
$8,181,070 | — | 31 Dec 2025 | |
| WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC |
13F
|
Company |
0.79%
|
984,906
|
$7,770,908 | — | 31 Dec 2025 | |
| NORTHERN TRUST CORP |
13F
|
Company |
0.77%
|
963,171
|
$7,599,419 | — | 31 Dec 2025 | |
| JUPITER ASSET MANAGEMENT LTD |
13F
|
Company |
0.77%
|
960,912
|
$7,581,595 | — | 31 Dec 2025 | |
| Qube Research & Technologies Ltd |
13F
|
Company |
0.7%
|
874,080
|
$6,896,491 | — | 31 Dec 2025 | |
| Sandra Wallach |
3/4/5
|
Chief Financial Officer |
0.8%
|
1,005,275
|
$6,852,155 | -$260,623 | 21 Aug 2025 | |
| Hood River Capital Management LLC |
13F
|
Company |
0.65%
|
809,744
|
$6,388,880 | — | 31 Dec 2025 | |
| Baird Financial Group, Inc. |
13F
|
Company |
0.62%
|
773,428
|
$6,102,347 | — | 31 Dec 2025 | |
| STIFEL FINANCIAL CORP |
13F
|
Company |
0.62%
|
771,509
|
$6,087,214 | — | 31 Dec 2025 | |
| BNP PARIBAS FINANCIAL MARKETS |
13F
|
Company |
0.56%
|
707,079
|
$5,578,853 | — | 31 Dec 2025 | |
| THAMES CAPITAL MANAGEMENT LLC |
13F
|
Company |
0.42%
|
526,832
|
$4,156,704 | — | 31 Dec 2025 | |
| ESSEX INVESTMENT MANAGEMENT CO LLC |
13F
|
Company |
0.41%
|
516,765
|
$4,077,276 | — | 31 Dec 2025 | |
| Ricardo C. Rodriguez |
3/4/5
|
Chief Financial Officer |
0.28%
|
350,000
|
$4,042,500 | — | 04 Mar 2026 | |
| Point72 Asset Management, L.P. |
13F
|
Company |
0.39%
|
493,862
|
$3,896,571 | — | 31 Dec 2025 | |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. |
13F
|
Company |
0.39%
|
490,886
|
$3,873,091 | — | 31 Dec 2025 | |
| TWO SIGMA ADVISERS, LP |
13F
|
Company |
0.38%
|
479,500
|
$3,783,255 | — | 31 Dec 2025 | |
| BARCLAYS PLC |
13F
|
Company |
0.38%
|
469,906
|
$3,707,558 | — | 31 Dec 2025 | |
| Artemis Investment Management LLP |
13F
|
Company |
0.37%
|
464,029
|
$3,661,189 | — | 31 Dec 2025 | |
| CITADEL ADVISORS LLC |
13F
|
Company |
0.36%
|
454,854
|
$3,588,798 | — | 31 Dec 2025 | |
| OSTERWEIS CAPITAL MANAGEMENT INC |
13F
|
Company |
0.36%
|
454,830
|
$3,588,609 | — | 31 Dec 2025 | |
| OPPENHEIMER & CO INC |
13F
|
Company |
0.35%
|
442,090
|
$3,488,090 | — | 31 Dec 2025 | |
| SEI INVESTMENTS CO |
13F
|
Company |
0.34%
|
431,786
|
$3,406,794 | — | 31 Dec 2025 | |
| Engineers Gate Manager LP |
13F
|
Company |
0.29%
|
360,401
|
$2,843,564 | — | 31 Dec 2025 | |
| SILVERCREST ASSET MANAGEMENT GROUP LLC |
13F
|
Company |
0.29%
|
359,386
|
$2,835,556 | — | 31 Dec 2025 | |
| Bank of New York Mellon Corp |
13F
|
Company |
0.25%
|
309,714
|
$2,443,640 | — | 31 Dec 2025 | |
| BANK OF AMERICA CORP /DE/ |
13F
|
Company |
0.24%
|
299,926
|
$2,366,417 | — | 31 Dec 2025 | |
| Steven Chu |
3/4/5
|
Director |
0.1%
|
127,339
|
$2,360,177 | -$5,863,984 | 10 Mar 2026 | |
| Verition Fund Management LLC |
13F
|
Company |
0.23%
|
292,097
|
$2,304,645 | — | 31 Dec 2025 | |
| POLEN CAPITAL MANAGEMENT LLC |
13F
|
Company |
0.23%
|
288,290
|
$2,274,608 | — | 31 Dec 2025 |
Recent Insider Transactions by Companies or Individuals for Amprius Technologies, Inc.
Showing up to 300 most recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | Value $ | * Price $ | Shares | Shares Owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| Kang Sun | AMPX | Common stock | Sale | -52.8% | $23,860,714 | $15.91 | -1,500,000 | 1,342,400 | 01 Apr 2026 | Direct |
| Kang Sun | AMPX | Common stock | Options Exercise | 111.7% | 1,500,000 | 2,842,400 | 01 Apr 2026 | Direct | ||
| Kang Sun | AMPX | Stock Option (right to buy) | Options Exercise | -100% | -1,500,000 | 0 | 01 Apr 2026 | Direct | ||
| Kang Sun | AMPX | Common stock | Sale | -79.4% | $4,095,402 | $18.80 | -217,869 | 56,406 | 23 Mar 2026 | See Footnote |
| Wen Hsuan Hsieh | AMPX | Common stock | Sale | -90.3% | $7,620,033 | $18.44 | -413,146 | 44,444 | 12 Mar 2026 | Direct |
| Wen Hsuan Hsieh | AMPX | Common stock | Options Exercise | 144.3% | 270,251 | 457,590 | 12 Mar 2026 | Direct | ||
| Wen Hsuan Hsieh | AMPX | Stock Option (right to buy) | Options Exercise | -100% | -270,251 | 0 | 12 Mar 2026 | Direct | ||
| Steven Chu | AMPX | Common stock | Sale | -55% | $2,878,555 | $18.50 | -155,565 | 127,339 | 12 Mar 2026 | Direct |
| Steven Chu | AMPX | Common stock | Options Exercise | 122.2% | 155,565 | 282,904 | 12 Mar 2026 | Direct | ||
| Steven Chu | AMPX | Stock Option (right to buy) | Options Exercise | -100% | -155,565 | 0 | 12 Mar 2026 | Direct | ||
| Steven Chu | AMPX | Common stock | Sale | -56.7% | $2,985,429 | $17.92 | -166,632 | 127,339 | 10 Mar 2026 | Direct |
| Steven Chu | AMPX | Common stock | Options Exercise | 54.8% | 104,132 | 293,971 | 10 Mar 2026 | Direct | ||
| Steven Chu | AMPX | Stock Option (right to buy) | Options Exercise | -60% | -104,132 | 69,422 | 10 Mar 2026 | Direct | ||
| Ricardo C. Rodriguez | AMPX | Common stock | Award | 75% | 150,000 | 350,000 | 04 Mar 2026 | Direct | ||
| Thomas M. Stepien | AMPX | Common stock | Award | 24.6% | 150,000 | 760,000 | 04 Mar 2026 | Direct | ||
| Constantin Ionel Stefan | AMPX | Common stock | Award | 15.2% | 110,000 | 833,330 | 04 Mar 2026 | Direct | ||
| Kang Sun | AMPX | Common stock | Sale | -4.36% | $622,035 | $10.16 | -61,251 | 1,342,400 | 23 Feb 2026 | Direct |
| Constantin Ionel Stefan | AMPX | Common stock | Sale | -3.39% | $257,604 | $10.16 | -25,366 | 723,330 | 23 Feb 2026 | Direct |
| Constantin Ionel Stefan | AMPX | Common stock | Sale | -5.03% | $476,351 | $12.00 | -39,690 | 748,696 | 28 Jan 2026 | Direct |
| Constantin Ionel Stefan | AMPX | Common stock | Options Exercise | 5.3% | 39,690 | 788,386 | 28 Jan 2026 | Direct | ||
| Constantin Ionel Stefan | AMPX | Stock Option (right to buy) | Options Exercise | -100% | -39,690 | 0 | 28 Jan 2026 | Direct | ||
| Constantin Ionel Stefan | AMPX | Common stock | Sale | -0.21% | $19,200 | $12.00 | -1,600 | 748,696 | 23 Jan 2026 | Direct |
| Constantin Ionel Stefan | AMPX | Common stock | Options Exercise | 0.21% | 1,600 | 750,296 | 23 Jan 2026 | Direct | ||
| Constantin Ionel Stefan | AMPX | Stock Option (right to buy) | Options Exercise | -3.88% | -1,600 | 39,600 | 23 Jan 2026 | Direct | ||
| Constantin Ionel Stefan | AMPX | Common stock | Sale | -39.7% | $5,931,912 | $12.04 | -492,827 | 748,696 | 22 Jan 2026 | Direct |
| Constantin Ionel Stefan | AMPX | Common stock | Options Exercise | 65.8% | 492,827 | 1,241,523 | 22 Jan 2026 | Direct | ||
| Constantin Ionel Stefan | AMPX | Stock Option (right to buy) | Options Exercise | -100% | -492,827 | 0 | 22 Jan 2026 | Direct | ||
| Constantin Ionel Stefan | AMPX | Common stock | Sale | -8.92% | $879,411 | $12.00 | -73,280 | 748,696 | 21 Jan 2026 | Direct |
| Constantin Ionel Stefan | AMPX | Common stock | Options Exercise | 9.79% | 73,280 | 821,976 | 21 Jan 2026 | Direct | ||
| Constantin Ionel Stefan | AMPX | Stock Option (right to buy) | Options Exercise | -99.9% | -73,280 | 90 | 21 Jan 2026 | Direct | ||
| Kang Sun | AMPX | Common stock | Sale | -2.98% | $476,274 | $11.03 | -43,185 | 1,403,651 | 20 Jan 2026 | Direct |
| Kang Sun | AMPX | Common stock | Options Exercise | 3.08% | 43,185 | 1,446,836 | 20 Jan 2026 | Direct | ||
| Kang Sun | AMPX | Stock Option (right to buy) | Options Exercise | -3.19% | -43,185 | 1,312,505 | 20 Jan 2026 | Direct | ||
| Kang Sun | AMPX | Common stock | Sale | -40.4% | $10,518,669 | $11.07 | -950,548 | 1,403,651 | 16 Jan 2026 | Direct |
| Kang Sun | AMPX | Common stock | Options Exercise | 67.7% | 950,548 | 2,354,199 | 16 Jan 2026 | Direct | ||
| Kang Sun | AMPX | Stock Option (right to buy) | Options Exercise | -100% | -950,548 | 0 | 16 Jan 2026 | Direct | ||
| Kang Sun | AMPX | Common stock | Sale | -26.5% | $5,111,474 | $10.10 | -506,267 | 1,403,651 | 12 Jan 2026 | Direct |
| Kang Sun | AMPX | Common stock | Options Exercise | 36.1% | 506,267 | 1,909,918 | 12 Jan 2026 | Direct | ||
| Kang Sun | AMPX | Stock Option (right to buy) | Options Exercise | -100% | -506,267 | 0 | 12 Jan 2026 | Direct | ||
| Thomas M. Stepien | AMPX | Common stock | Award | 48.8% | 200,000 | 610,000 | 19 Dec 2025 | Direct | ||
| Constantin Ionel Stefan | AMPX | Common stock | Sale | -20.9% | $2,083,382 | $10.51 | -198,255 | 748,696 | 11 Dec 2025 | Direct |
| Constantin Ionel Stefan | AMPX | Common stock | Options Exercise | 15.2% | 125,000 | 946,951 | 11 Dec 2025 | Direct | ||
| Constantin Ionel Stefan | AMPX | Stock Option (right to buy) | Options Exercise | -28.7% | -125,000 | 310,962 | 11 Dec 2025 | Direct | ||
| Constantin Ionel Stefan | AMPX | Common stock | Sale | -2.95% | $252,274 | $10.08 | -25,024 | 821,951 | 21 Nov 2025 | Direct |
| Kang Sun | AMPX | Common stock | Sale | -4.66% | $692,132 | $10.08 | -68,655 | 1,403,651 | 21 Nov 2025 | Direct |
| Kang Sun | AMPX | Common stock | Sale | -40.4% | $10,595,300 | $10.60 | -1,000,000 | 1,472,306 | 17 Nov 2025 | Direct |
| Kang Sun | AMPX | Common stock | Options Exercise | 67.9% | 1,000,000 | 2,472,306 | 17 Nov 2025 | Direct | ||
| Kang Sun | AMPX | Stock Option (right to buy) | Options Exercise | -100% | -1,000,000 | 0 | 17 Nov 2025 | Direct | ||
| Ricardo C. Rodriguez | AMPX | Common stock | Award | 200,000 | 200,000 | 06 Oct 2025 | Direct | |||
| Constantin Ionel Stefan | AMPX | Common stock | Sale | -2.21% | $130,592 | $6.82 | -19,159 | 846,975 | 21 Aug 2025 | Direct |
* An asterisk sign (*) next to the price indicates that the price is likely invalid.