Who owns Amprius Technologies (AMPX)
Which tracked institutional funds hold AMPX, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See AMPX company fundamentals →
Ownership as of the 2026-Q2 13F filings (latest filed 2026-09-22). 13F is disclosed up to 45 days after quarter-end, so the most recent quarter fills in over the following weeks.
How the tape is positioned
60 tracked funds added or opened AMPX while 86 trimmed or exited it between 2026-Q1 and 2026-Q2 — the tape is split. When large holders disagree on a name, the funds moving first are sometimes ahead of the story.
A prompt to read the filings, not a verdict. 13F is a quarter-end snapshot disclosed up to 45 days late; a fund adds or exits for mandate, benchmark, and timing reasons that have nothing to do with a view on the stock. This is a starting question, not a signal to trade.
Conviction spread
AMPX’s largest tracked holder by dollar value, BlackRock, Inc., sizes it at 0.0% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 0.0pp gap the other way — the median holder sizes AMPX more heavily than its largest holder by dollar value does.
Book-share is each fund’s reported value in AMPX divided by its whole reported 13F book, so it is comparable across funds of different sizes and is unaffected by stock splits. A higher share means a fund has committed more of its book to the name — a starting question about conviction, not a verdict or a signal to trade.
Institutional & insider positioning
Between 2026-Q1 and 2026-Q2, across 254 tracked filers holding AMPX, 165 increased or opened the position and 127 reduced or closed it; over the same quarter, open-market insider Form 4s were net sales.
This fuses two public signals for the same quarter — how tracked institutions changed their positions and whether insiders bought or sold in the open market. It describes what was filed; it is a starting question, not a verdict or a signal to trade.
New buyers & exits
Funds opening or closing a position in AMPX between the 2026-Q1 and 2026-Q2 13F filings, and the largest changes among funds holding it in both. New buyers and exits are counted on fund presence (split-invariant); adds and trims are measured on reported value.
New buyers 23
- JUPITER ASSET MANAGEMENT LTD$30M
- HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND$17M
- Nearwater Capital Markets, Ltd$14M
- Shannon River Fund Management LLC$12M
- TimesSquare Capital Management, LLC$9M
- Coppell Advisory Solutions LLC$6M
Full exits 31
- WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC$20M
- HRT FINANCIAL LP$17M
- MYDA Advisors LLC$12M
- Science & Technology Partners, L.P.$11M
- VOLORIDGE INVESTMENT MANAGEMENT, LLC$9M
- THAMES CAPITAL MANAGEMENT LLC$9M
Largest adds
- UBS Group AG$17M
- MORGAN STANLEY$17M
- Point72 Asset Management, L.P.$15M
- SUSQUEHANNA INTERNATIONAL GROUP, LLP$14M
- RENAISSANCE TECHNOLOGIES LLC$13M
- IMC-Chicago, LLC$9M
Largest trims
- Driehaus Capital Management LLC$45M
- MASSACHUSETTS FINANCIAL SERVICES CO /MA/$27M
- JANE STREET GROUP, LLC$23M
- MARSHALL WACE, LLP$19M
- JPMORGAN CHASE & CO$16M
- PRICE T ROWE ASSOCIATES INC /MD/$9M
Institutional holders
One row per tracked fund, most shares held first (every row is from one quarter; reported value breaks ties). “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding.
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| BlackRock, Inc. added | 11,335,092 | $157M | 12.1% | 2026-Q2 |
| VANGUARD CAPITAL MANAGEMENT LLC added | 5,562,985 | $77M | 5.9% | 2026-Q2 |
| MORGAN STANLEY added | 5,105,505 | $71M | 5.5% | 2026-Q2 |
| TWO SIGMA INVESTMENTS, LP added | 4,318,630 | $60M | 4.6% | 2026-Q2 |
| UBS Group AG added | 4,072,269 | $56M | 4.4% | 2026-Q2 |
| GEODE CAPITAL MANAGEMENT, LLC added | 3,520,655 | $49M | 3.8% | 2026-Q2 |
| JANE STREET GROUP, LLC trimmed | 3,401,071 | $47M | 3.6% | 2026-Q2 |
| STATE STREET CORP added | 3,240,285 | $45M | 3.5% | 2026-Q2 |
| GOLDMAN SACHS GROUP INC added | 2,542,294 | $35M | 2.7% | 2026-Q2 |
| JUPITER ASSET MANAGEMENT LTD added | 2,133,397 | $30M | 2.3% | 2026-Q2 |
| LMR Partners LLP trimmed | 1,750,850 | $24M | 1.9% | 2026-Q2 |
| CITADEL ADVISORS LLC added | 1,676,344 | $23M | 1.8% | 2026-Q2 |
| PRICE T ROWE ASSOCIATES INC /MD/ trimmed | 1,635,883 | $23M | 1.7% | 2026-Q2 |
| VANGUARD PORTFOLIO MANAGEMENT LLC added | 1,457,629 | $20M | 1.6% | 2026-Q2 |
| Caption Management, LLC added | 1,432,795 | $8M | 0.6% | 2026-Q2 |
| Hood River Capital Management LLC added | 1,412,516 | $20M | 1.5% | 2026-Q2 |
| RENAISSANCE TECHNOLOGIES LLC added | 1,408,925 | $20M | 1.5% | 2026-Q2 |
| Driehaus Capital Management LLC trimmed | 1,345,269 | $19M | 1.4% | 2026-Q2 |
| Baird Financial Group, Inc. trimmed | 1,324,909 | $18M | 1.4% | 2026-Q2 |
| HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND new | 1,248,700 | $17M | 1.3% | 2026-Q2 |
| NORTHERN TRUST CORP added | 1,229,628 | $17M | 1.3% | 2026-Q2 |
| MILLENNIUM MANAGEMENT LLC added | 1,208,017 | $17M | 1.3% | 2026-Q2 |
| DEUTSCHE BANK AG\ added | 1,196,197 | $17M | 1.3% | 2026-Q2 |
| BARCLAYS PLC added | 1,180,878 | $16M | 1.3% | 2026-Q2 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC added | 1,176,959 | $16M | 1.3% | 2026-Q2 |
| Point72 Asset Management, L.P. added | 1,139,811 | $16M | 1.2% | 2026-Q2 |
| Qube Research & Technologies Ltd trimmed | 1,136,175 | $16M | 1.2% | 2026-Q2 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP added | 1,100,269 | $15M | 1.2% | 2026-Q2 |
| Trexquant Investment LP added | 1,097,532 | $15M | 1.2% | 2026-Q2 |
| FIRST TRUST ADVISORS LP added | 1,037,344 | $14M | 1.1% | 2026-Q2 |
| Nearwater Capital Markets, Ltd new | 1,034,700 | $14M | 1.1% | 2026-Q2 |
| VANGUARD FIDUCIARY TRUST CO added | 989,691 | $14M | 1.1% | 2026-Q2 |
| Shannon River Fund Management LLC new | 838,887 | $12M | 0.9% | 2026-Q2 |
| TUDOR INVESTMENT CORP ET AL added | 747,428 | $10M | 0.8% | 2026-Q2 |
| IMC-Chicago, LLC added | 734,114 | $10M | 0.8% | 2026-Q2 |
| STIFEL FINANCIAL CORP trimmed | 731,470 | $10M | 0.8% | 2026-Q2 |
| Stephens Investment Management Group LLC trimmed | 714,324 | $10M | 0.8% | 2026-Q2 |
| D. E. Shaw & Co., Inc. trimmed | 671,812 | $9M | 0.7% | 2026-Q2 |
| TimesSquare Capital Management, LLC new | 641,990 | $9M | 0.7% | 2026-Q2 |
| OBERWEIS ASSET MANAGEMENT INC/ added | 636,200 | $9M | 0.7% | 2026-Q2 |
| Invesco Ltd. added | 571,613 | $8M | 0.6% | 2026-Q2 |
| Wolf Hill Capital Management, LP trimmed | 527,259 | $7M | 0.6% | 2026-Q2 |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. added | 523,062 | $7M | 0.6% | 2026-Q2 |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ trimmed | 506,268 | $7M | 0.5% | 2026-Q2 |
| OPPENHEIMER & CO INC added | 504,746 | $7M | 0.5% | 2026-Q2 |
| DNB Asset Management AS added | 491,965 | $7M | 0.5% | 2026-Q2 |
| POLEN CAPITAL MANAGEMENT LLC added | 465,598 | $6M | 0.5% | 2026-Q2 |
| SEI INVESTMENTS CO trimmed | 443,230 | $6M | 0.5% | 2026-Q2 |
| FEDERATED HERMES, INC. added | 428,693 | $6M | 0.5% | 2026-Q2 |
| ALGERT GLOBAL LLC added | 424,833 | $6M | 0.5% | 2026-Q2 |
| Bank of New York Mellon Corp added | 417,415 | $6M | 0.4% | 2026-Q2 |
| Nuveen, LLC added | 397,802 | $6M | 0.4% | 2026-Q2 |
| ZEVENBERGEN CAPITAL INVESTMENTS LLC added | 381,420 | $5M | 0.4% | 2026-Q2 |
| Palisades Investment Partners, LLC trimmed | 368,459 | $5M | 0.4% | 2026-Q2 |
| DRW Securities, LLC added | 356,445 | $2M | 0.2% | 2026-Q2 |
| Sender Co & Partners, Inc. added | 355,692 | $5M | 0.4% | 2026-Q2 |
| Allspring Global Investments Holdings, LLC trimmed | 345,972 | $5M | 0.4% | 2026-Q2 |
| WELLINGTON MANAGEMENT GROUP LLP new | 342,797 | $5M | 0.4% | 2026-Q2 |
| BANK OF AMERICA CORP /DE/ added | 327,846 | $5M | 0.4% | 2026-Q2 |
| SILVERCREST ASSET MANAGEMENT GROUP LLC trimmed | 305,581 | $4M | 0.3% | 2026-Q2 |
| ESSEX INVESTMENT MANAGEMENT CO LLC trimmed | 284,595 | $4M | 0.3% | 2026-Q2 |
| CREDIT AGRICOLE S A new | 265,189 | $4M | 0.3% | 2026-Q2 |
| HSBC HOLDINGS PLC new | 259,508 | $4M | 0.3% | 2026-Q2 |
| Swiss National Bank added | 247,500 | $3M | 0.3% | 2026-Q2 |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC trimmed | 220,103 | $3M | 0.2% | 2026-Q2 |
| GROUP ONE TRADING LLC added | 213,312 | $3M | 0.2% | 2026-Q2 |
| Voleon Capital Management LP trimmed | 205,345 | $3M | 0.2% | 2026-Q2 |
| Russell Investments Group, Ltd. trimmed | 202,959 | $3M | 0.2% | 2026-Q2 |
| WELLS FARGO & COMPANY/MN added | 197,771 | $3M | 0.2% | 2026-Q2 |
| BLAIR WILLIAM & CO/IL added | 194,712 | $3M | 0.2% | 2026-Q2 |
| Aquatic Capital Management LLC trimmed | 189,235 | $3M | 0.2% | 2026-Q2 |
| HITE Hedge Asset Management LLC added | 186,393 | $3M | 0.2% | 2026-Q2 |
| ALPS ADVISORS INC added | 184,483 | $3M | 0.2% | 2026-Q2 |
| NEW YORK STATE COMMON RETIREMENT FUND added | 184,227 | $3M | 0.2% | 2026-Q2 |
| BNP PARIBAS FINANCIAL MARKETS trimmed | 183,631 | $3M | 0.2% | 2026-Q2 |
| XTX Topco Ltd added | 180,174 | $2M | 0.2% | 2026-Q2 |
| ExodusPoint Capital Management, LP added | 179,272 | $2M | 0.2% | 2026-Q2 |
| AQR CAPITAL MANAGEMENT LLC added | 173,155 | $2M | 0.2% | 2026-Q2 |
| Huntleigh Advisors, Inc. added | 171,028 | $2M | 0.2% | 2026-Q2 |
| RHUMBLINE ADVISERS added | 167,963 | $2M | 0.2% | 2026-Q2 |
| VOYA INVESTMENT MANAGEMENT LLC added | 158,658 | $2M | 0.2% | 2026-Q2 |
| ALLIANCEBERNSTEIN L.P. added | 152,060 | $3M | 0.2% | 2026-Q2 |
| CANTOR FITZGERALD, L. P. new | 147,909 | $2M | 0.2% | 2026-Q2 |
| LPL Financial LLC added | 147,233 | $2M | 0.2% | 2026-Q2 |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM trimmed | 141,264 | $2M | 0.2% | 2026-Q2 |
| MARSHALL WACE, LLP trimmed | 131,200 | $2M | 0.1% | 2026-Q2 |
| Marex Group Ltd added | 126,930 | $2M | 0.1% | 2026-Q2 |
| JPMORGAN CHASE & CO trimmed | 123,377 | $2M | 0.1% | 2026-Q2 |
| Clear Street Group Inc. added | 122,474 | $2M | 0.1% | 2026-Q2 |
| CANADA PENSION PLAN INVESTMENT BOARD added | 119,600 | $2M | 0.1% | 2026-Q2 |
| Foundations Investment Advisors, LLC added | 119,465 | $2M | 0.1% | 2026-Q2 |
| Legato Capital Management LLC trimmed | 118,793 | $2M | 0.1% | 2026-Q2 |
| SLT Holdings LLC added | 117,750 | $2M | 0.1% | 2026-Q2 |
| ROYAL BANK OF CANADA added | 115,322 | $2M | 0.1% | 2026-Q2 |
| Lisanti Capital Growth, LLC trimmed | 113,710 | $2M | 0.1% | 2026-Q2 |
| NOMURA HOLDINGS INC new | 109,808 | $2M | 0.1% | 2026-Q2 |
| Legal & General Group Plc added | 107,923 | $1M | 0.1% | 2026-Q2 |
| HUSSMAN STRATEGIC ADVISORS, INC. trimmed | 105,000 | $1M | 0.1% | 2026-Q2 |
| Faithward Advisors, LLC added | 102,448 | $1M | 0.1% | 2026-Q2 |
| Coppell Advisory Solutions LLC new | 500 | $6M | 0.5% | 2026-Q2 |
Ownership over time
Tracked institutional holder count and total shares held by filing quarter (independent scales). The curated-era tail and any mid-ingest latest quarter are handled honestly — a partial quarter is not drawn as a collapse.
Reading this table
Funds hold the same stock for different reasons — an index fund “holds” almost everything, an active manager sizes a name to a mandate and a benchmark, and each fund entered at its own price and time. Because 13F is filed up to 45 days after quarter-end, every row is a backward-looking snapshot; a manager may have traded since. Share-class siblings (a company’s A and C shares) are rolled up to one line so a dual-class name is never double-counted. Compare like-for-like. A large holder is not an endorsement, and a fund exiting is not a warning — this is a starting question, not a verdict.
About 13F filings
A Form 13F is a quarterly disclosure that institutional investment managers with over $100 million in US-listed equities must file with the SEC. In plain English: it is a snapshot of the long stock positions a fund held at the end of a quarter. It covers long US-listed equities only — not short positions, options, cash, or private holdings — and the funds shown are the large sample we track, not the complete 13F universe.