AMPRIUS TECHNOLOGIES INC AMPX
COMMON STOCK · Common Stock · CUSIP 03214Q108 · ISIN US03214Q1085
- SectorIndustrials
- IndustryMiscellaneous Electrical Machinery, Equipment & Supplies
- HeadquartersFremont, CA
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($2.4m this quarter). Holder counts are more reliable. Shares outstanding: 130.5m as of 2025-10-30, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $10.52. Options: 9 managers hold calls ($60.3m notional), 8 hold puts ($12.9m).
Trends to Q3 2025
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 14 |
| Q4 2022 | 23 |
| Q1 2023 | 27 |
| Q2 2023 | 42 |
| Q3 2023 | 47 |
| Q4 2023 | 50 |
| Q1 2024 | 51 |
| Q2 2024 | 66 |
| Q3 2024 | 67 |
| Q4 2024 | 92 |
| Q1 2025 | 101 |
| Q2 2025 | 122 |
| Q3 2025 | 187 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q4 2023 | 29 | 11 |
| Q1 2024 | 24 | 23 |
| Q2 2024 | 43 | 13 |
| Q3 2024 | 38 | 22 |
| Q4 2024 | 61 | 21 |
| Q1 2025 | 64 | 36 |
| Q2 2025 | 84 | 38 |
| Q3 2025 | 149 | 45 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q4 2024 | $10.2m | $602.5k | 0.06 |
| Q1 2025 | $4.8m | $1.0m | 0.21 |
| Q2 2025 | $9.6m | $934.2k | 0.10 |
| Q3 2025 | $60.3m | $12.9m | 0.21 |
Biggest buyers
| Driehaus Capital Management LLC | New | +3.1m |
| CITADEL ADVISORS LLC | Added | +2.2m |
| BlackRock, Inc. | Added | +2.2m |
| DEUTSCHE BANK AG\ | Added | +2.0m |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC | New | +1.9m |
| BNP PARIBAS FINANCIAL MARKETS | Added | +1.8m |
| VANGUARD GROUP INC | Added | +1.8m |
| Invesco Ltd. | Added | +1.3m |
| GOLDMAN SACHS GROUP INC | Added | +1.2m |
| Stephens Investment Management Group LLC | New | +1.1m |
Biggest sellers
| MILLENNIUM MANAGEMENT LLC | Reduced | -3.0m |
| RENAISSANCE TECHNOLOGIES LLC | Reduced | -1.3m |
| Board of Trustees of The Leland Stanford Junior University | Sold out | -1.1m |
| MARSHALL WACE, LLP | Reduced | -1.1m |
| JPMORGAN CHASE & CO | Reduced | -441.8k |
| ESSEX INVESTMENT MANAGEMENT CO LLC | Reduced | -328.0k |
| Polar Asset Management Partners Inc. | Sold out | -274.8k |
| PRICE T ROWE ASSOCIATES INC /MD/ | Reduced | -273.9k |
| OPPENHEIMER & CO INC | Reduced | -149.9k |
| BRIDGEWAY CAPITAL MANAGEMENT, LLC | Sold out | -135.0k |
Biggest calls
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $17.1m1.6m shares |
| SIMPLEX TRADING, LLC | Added | $8.0m764.1k shares |
| BARCLAYS PLC | Unchanged | $7.9m750.0k shares |
| CITADEL ADVISORS LLC | Added | $7.4m705.1k shares |
| JANE STREET GROUP, LLC | Added | $6.9m659.2k shares |
| GROUP ONE TRADING LLC | Added | $5.8m554.7k shares |
| IMC-Chicago, LLC | Added | $4.9m467.1k shares |
| PEAK6 LLC | New | $1.6m150.0k shares |
| SYMMETRY PEAK MANAGEMENT LLC | New | $514.4k48.9k shares |
Biggest puts
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $4.3m404.9k shares |
| CITADEL ADVISORS LLC | Added | $2.6m250.0k shares |
| FIRST SABREPOINT CAPITAL MANAGEMENT LP | New | $1.9m180.6k shares |
| GROUP ONE TRADING LLC | Added | $1.3m128.1k shares |
| JANE STREET GROUP, LLC | New | $1.1m109.2k shares |
| IMC-Chicago, LLC | New | $857.4k81.5k shares |
| SIMPLEX TRADING, LLC | Added | $789.0k75.0k shares |
| JPMORGAN CHASE & CO | New | $4.2k400 shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| BlackRock, Inc. 13G · institution +1.6 pts · filed 2026-07-27 | 7.4% |
Fell to 5% or below in the last year: JANE STREET GROUP, LLC (3.3%, 2026-08-10), VANGUARD GROUP INC (0.0%, 2026-03-26)
Insider purchases and sales in Q3 2025
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q4 2023 | 0 | — | 2 | $4.1m | $1.7m |
| Q1 2024 | 0 | — | 1 | $1.8m | $1.8m |
| Q2 2024 | 0 | — | 5 | $1.4m | $299.8k |
| Q3 2024 | 0 | — | 5 | $724.5k | — |
| Q4 2024 | 0 | — | 4 | $438.0k | — |
| Q1 2025 | 0 | — | 4 | $235.0k | — |
| Q2 2025 | 0 | — | 3 | $286.1k | — |
| Q3 2025 | 0 | — | 3 | $772.0k | — |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2025-08-21 | Sun Kang Chief Executive Officer, director | Sold | $447.8k65.7k shares |
| 2025-08-21 | Wallach Sandra Chief Financial Officer | Sold | $193.6k28.4k shares |
| 2025-08-21 | Stefan Constantin Ionel Chief Technology Officer | Sold | $130.7k19.2k shares |
Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).
Holders, Q3 2025
| Manager | Shares | Change |
|---|---|---|
| BlackRock, Inc. 0.00% of their portfolio | 7.5m $78.4m | Added +2.2m |
| VANGUARD GROUP INC 0.00% of their portfolio | 6.5m $68.5m | Added +1.8m |
| Driehaus Capital Management LLC 0.23% of their portfolio | 3.1m $32.5m | New |
| MORGAN STANLEY 0.00% of their portfolio | 2.7m $28.9m | Added +810.1k |
| CITADEL ADVISORS LLC 0.02% of their portfolio | 2.5m $26.4m | Added +2.2m |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 2.4m $25.5m | Added +831.3k |
| Invesco Ltd. 0.00% of their portfolio | 2.4m $25.0m | Added +1.3m |
| STATE STREET CORP 0.00% of their portfolio | 2.2m $23.0m | Added +1.0m |
| DEUTSCHE BANK AG\ 0.01% of their portfolio | 2.1m $21.7m | Added +2.0m |
| BNP PARIBAS FINANCIAL MARKETS 0.02% of their portfolio | 1.9m $20.4m | Added +1.8m |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC 0.07% of their portfolio | 1.9m $19.7m | New |
| GOLDMAN SACHS GROUP INC 0.00% of their portfolio | 1.8m $18.8m | Added +1.2m |
| TWO SIGMA INVESTMENTS, LP 0.03% of their portfolio | 1.8m $18.4m | Added +342.0k |
| UBS Group AG 0.00% of their portfolio | 1.5m $16.3m | Added +816.5k |
| Stephens Investment Management Group LLC 0.15% of their portfolio | 1.1m $11.4m | New |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio | 974.5k $10.3m | Added +477.6k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.01% of their portfolio | 905.5k $9.5m | Added +28.1k |
| Baird Financial Group, Inc. 0.01% of their portfolio | 876.9k $9.2m | Reduced -123.8k |
| NORTHERN TRUST CORP 0.00% of their portfolio | 852.3k $9.0m | Added +189.7k |
| TWO SIGMA ADVISERS, LP 0.02% of their portfolio | 812.0k $8.5m | Added +409.6k |
| STIFEL FINANCIAL CORP 0.01% of their portfolio | 795.8k $8.4m | Reduced -100.4k |
| TUDOR INVESTMENT CORP ET AL 0.05% of their portfolio | 715.7k $7.5m | New |
| ESSEX INVESTMENT MANAGEMENT CO LLC 1.12% of their portfolio | 697.4k $7.3m | Reduced -328.0k |
| Capitolis Liquid Global Markets LLC 0.06% of their portfolio | 680.6k $7.2m | New |
| JANE STREET GROUP, LLC 0.01% of their portfolio | 676.7k $7.1m | Added +654.3k |
| MILLENNIUM MANAGEMENT LLC 0.00% of their portfolio | 587.8k $6.2m | Reduced -3.0m |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 575.4k $6.1m | Reduced -441.8k |
| THAMES CAPITAL MANAGEMENT LLC 0.80% of their portfolio | 526.8k $5.5m | New |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 0.01% of their portfolio | 510.5k $5.4m | Added +459.4k |
| Informed Momentum Co LLC 0.58% of their portfolio | 488.5k $5.1m | Added +277.3k |
| Artemis Investment Management LLP 0.06% of their portfolio | 478.5k $5.0m | New |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP 0.00% of their portfolio | 471.8k $5.0m | New |
| ALGERT GLOBAL LLC 0.07% of their portfolio | 383.0k $4.0m | New |
| POLEN CAPITAL MANAGEMENT LLC 0.01% of their portfolio | 339.4k $3.6m | New |
| Verition Fund Management LLC 0.02% of their portfolio | 323.4k $3.4m | Added +145.8k |
| Russell Investments Group, Ltd. 0.00% of their portfolio | 305.1k $3.2m | Added +299.3k |
| OPPENHEIMER & CO INC 0.04% of their portfolio | 299.3k $3.1m | Reduced -149.9k |
| Bank of New York Mellon Corp 0.00% of their portfolio | 291.9k $3.1m | Added +98.2k |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 290.4k $3.1m | Added +163.7k |
| Janney Montgomery Scott LLC 0.01% of their portfolio | 283.5k $3.0m | Added +267.5k |
| Lisanti Capital Growth, LLC 0.68% of their portfolio | 265.7k $2.8m | New |
| Legato Capital Management LLC 0.29% of their portfolio | 251.3k $2.6m | Reduced -25.6k |
| Trexquant Investment LP 0.03% of their portfolio | 249.3k $2.6m | New |
| Jump Financial, LLC 0.03% of their portfolio | 242.7k $2.6m | New |
| Nuveen, LLC 0.00% of their portfolio | 242.3k $2.5m | Added +25.1k |
| RAYMOND JAMES FINANCIAL INC 0.00% of their portfolio | 240.0k $2.5m | Added +229.1k |
| NEXT CENTURY GROWTH INVESTORS LLC 0.18% of their portfolio | 228.6k $2.4m | New |
| JUPITER ASSET MANAGEMENT LTD 0.02% of their portfolio | 199.4k $2.1m | New |
| Engineers Gate Manager LP 0.02% of their portfolio | 188.8k $2.0m | New |
| OSTERWEIS CAPITAL MANAGEMENT INC 0.09% of their portfolio | 187.4k $2.0m | New |
| Quadrature Capital Ltd 0.02% of their portfolio | 180.2k $1.9m | New |
| Swiss National Bank 0.00% of their portfolio | 175.3k $1.8m | New |
| Cubist Systematic Strategies, LLC 0.03% of their portfolio | 174.8k $1.8m | Added +4.4k |
| XTX Topco Ltd 0.09% of their portfolio | 173.0k $1.8m | Added +162.6k |
| Calamos Advisors LLC 0.01% of their portfolio | 171.1k $1.8m | New |
| LPL Financial LLC 0.00% of their portfolio | 165.4k $1.7m | Added +39.7k |
| Huntleigh Advisors, Inc. 0.28% of their portfolio | 156.1k $1.6m | Added +10.2k |
| HRT FINANCIAL LP 0.01% of their portfolio | 150.6k $1.6m | Reduced -65.1k |
| ALPS ADVISORS INC 0.01% of their portfolio | 148.8k $1.6m | New |
| BARCLAYS PLC 0.00% of their portfolio | 133.3k $1.4m | Reduced -34.2k |
| Quantbot Technologies LP 0.04% of their portfolio | 131.9k $1.4m | New |
| AQR CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 131.5k $1.4m | Added +51.5k |
| CAPITAL FUND MANAGEMENT S.A. 0.01% of their portfolio | 131.4k $1.4m | New |
| PRUDENTIAL FINANCIAL INC 0.00% of their portfolio | 131.2k $1.4m | Added +120.4k |
| Walleye Capital LLC 0.01% of their portfolio | 130.8k $1.4m | New |
| RHUMBLINE ADVISERS 0.00% of their portfolio | 130.0k $1.4m | Added +6.7k |
| ROYAL BANK OF CANADA 0.00% of their portfolio | 127.4k $1.3m | Added +96.0k |
| ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio | 123.9k $1.3m | Reduced -40.2k |
| Foundations Investment Advisors, LLC 0.02% of their portfolio | 121.1k $1.3m | Added +28.7k |
| SLT Holdings LLC 0.83% of their portfolio | 120.3k $1.3m | Added +28.6k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio | 116.5k $1.2m | New |
| GSA CAPITAL PARTNERS LLP 0.09% of their portfolio | 101.1k $1.1m | Added +28.0k |
| CITIGROUP INC 0.00% of their portfolio | 96.7k $1.0m | Added +62.4k |
| FEDERATED HERMES, INC. 0.00% of their portfolio | 91.8k $965.8k | New |
| Entropy Technologies, LP 0.07% of their portfolio | 90.1k $947.9k | New |
| Legal & General Group Plc 0.00% of their portfolio | 87.4k $919.2k | Added +77.0k |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio | 83.6k $879.7k | Added +77.8k |
| SEI INVESTMENTS CO 0.00% of their portfolio | 78.7k $828.1k | Added +68.5k |
| KINGSWOOD WEALTH ADVISORS, LLC 0.05% of their portfolio | 77.7k $817.5k | Reduced -7.7k |
| Numerai GP LLC 0.11% of their portfolio | 74.5k $783.9k | New |
| PICTON MAHONEY ASSET MANAGEMENT 0.01% of their portfolio | 71.0k $746.0k | New |
| Brevan Howard Capital Management LP 0.01% of their portfolio | 69.8k $734.2k | New |
| Schonfeld Strategic Advisors LLC 0.00% of their portfolio | 65.4k $687.9k | New |
| OMERS ADMINISTRATION Corp 0.00% of their portfolio | 64.4k $677.5k | Added +14.8k |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 58.8k $618.2k | Added +8.1k |
| Mirae Asset Global Investments Co., Ltd. 0.00% of their portfolio | 58.4k $614.7k | New |
| MetLife Investment Management, LLC 0.00% of their portfolio | 58.2k $612.3k | Unchanged |
| HITE Hedge Asset Management LLC 0.03% of their portfolio | 57.8k $608.1k | Reduced -103.6k |
| Squarepoint Ops LLC 0.00% of their portfolio | 57.6k $606.0k | Reduced -7.8k |
| Dynamic Technology Lab Private Ltd 0.09% of their portfolio | 51.5k $542.0k | Added +21.3k |
| B. Riley Wealth Advisors, Inc. 0.03% of their portfolio | 50.7k $533.4k | Added +200 |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio | 49.1k $517.0k | Reduced -273.9k |
| Allspring Global Investments Holdings, LLC 0.00% of their portfolio | 49.1k $591.2k | New |
| Graham Capital Management, L.P. 0.02% of their portfolio | 48.0k $505.4k | Reduced -93.5k |
| Counterpoint Mutual Funds LLC 0.04% of their portfolio | 47.6k $501.2k | New |
| Inspire Investing, LLC 0.04% of their portfolio | 43.8k $461.1k | New |
| BESSEMER GROUP INC 0.00% of their portfolio | 41.3k $435.0k | Unchanged |
| Harbour Capital Advisors, LLC 0.10% of their portfolio | 40.3k $510.8k | New |
| JANUS HENDERSON GROUP PLC 0.00% of their portfolio | 39.1k $411.0k | New |
| CoreCommodity Management, LLC 0.07% of their portfolio | 38.8k $407.9k | New |