Institutional ownership · Form 13F
AMPX institutional ownership
Amprius Technologies, Inc.: reported institutional holdings as of 2026-06-30 (filed through 2026-08-31), aggregated by StockEyes from SEC Form 13F information tables. AMPX is one of 2732 tickers in the validated publication set. Mapping coverage in this publication set: 4562 of 6046 universe tickers have at least one validated CUSIP mapping (75.5%). Latest-quarter filed value resolved to any listed ticker: 77.3%; resolved to this universe: 77.2%.
AMPX: change since the prior quarter's filings
More managers reported a position, with the count rising from 254 in the quarter ended 2026-03-31 to 268 in the quarter ended 2026-06-30 (+14, 5.5%). Total reported shares rose to 101,583,226 (+7,398,737, 7.9%), moving the same way as the manager count. Among the 22 managers listed as top holders in both quarters, the largest increases were BlackRock, Inc. (+2,109,481 shares) and MORGAN STANLEY (+1,943,338 shares), among 17 managers who added shares, and the largest decreases were Driehaus Capital Management LLC (-2,448,909 shares) and LMR Partners LLP (-839,732 shares), among 5 managers who reduced shares. JUPITER ASSET MANAGEMENT LTD (2,133,397 shares), RENAISSANCE TECHNOLOGIES LLC (1,408,925 shares) and 6 more entered the listed top holders; MASSACHUSETTS FINANCIAL SERVICES CO /MA/ (2,024,760 shares in the prior quarter), MARSHALL WACE, LLP (1,227,599 shares in the prior quarter) and 6 more dropped out of the listed top holders.
New to 13F data? Read how to read a 13F filing, or see where institutions moved overall in the Smart Money Report.
Reported totals, quarter ended 2026-06-30
268 reporting managers held 101,583,226 shares, reported value $1,347,826,550 exactly as filed. Values are position values transcribed from the filings, not current market prices.
Reported quarter-over-quarter change (quarter ended 2026-03-31 to quarter ended 2026-06-30): reporting managers +14, reported shares +7,398,737 (+7.86%), reported value -5.61%. These changes compare two filing snapshots.
Shares outstanding check: 146,080,618 shares reported by the issuer (SEC XBRL, period ended 2026-07-31). Reported 13F shares equal 69.5% of that figure. This page passed the publication sanity gate before listing.
AMPX in this quarter's filings
Concentration check: the largest reported position, BlackRock, Inc. with 11,335,092 shares, is 11.2% of all shares reported for AMPX this quarter. The five largest reporting managers together account for 29.9% of the reported total, so the headline total is spread across a broad manager base rather than a few holders.
Reported quarter-over-quarter change: the reporting-manager count rose by 14 versus the quarter ended 2026-03-31, and reported shares moved +7.86% (+7,398,737 shares). That is a comparison of two filing snapshots, not a record of trades on any single day.
Shares-outstanding cross-check: reported 13F shares equal 69.5% of the issuer share count used at the publication gate (146,080,618 shares, issuer period ended 2026-07-31). The gate publishes a ticker only when that relationship is plausible; lending chains can push reported totals above a simple ownership share, which is why the figure is a sanity check and not an ownership percentage.
Largest reporting managers, AMPX
| # | Manager | Shares | Value as filed | Share of reported total |
|---|---|---|---|---|
| 1 | BlackRock, Inc. | 11,335,092 | $157,104,377 | 11.2% |
| 2 | VANGUARD CAPITAL MANAGEMENT LLC | 5,562,985 | $77,102,972 | 5.5% |
| 3 | MORGAN STANLEY | 5,105,505 | $70,762,300 | 5.0% |
| 4 | TWO SIGMA INVESTMENTS, LP | 4,318,630 | $59,856,212 | 4.3% |
| 5 | UBS Group AG | 4,073,080 | $56,446,401 | 4.0% |
| 6 | GEODE CAPITAL MANAGEMENT, LLC | 3,520,655 | $48,805,499 | 3.5% |
| 7 | JANE STREET GROUP, LLC | 3,401,071 | $47,138,844 | 3.3% |
| 8 | STATE STREET CORP | 3,240,285 | $44,910,350 | 3.2% |
| 9 | LMR Partners LLP | 3,650,110 | $35,396,445 | 3.6% |
| 10 | GOLDMAN SACHS GROUP INC | 2,542,294 | $35,236,188 | 2.5% |
| 11 | JUPITER ASSET MANAGEMENT LTD | 2,133,397 | $29,568,882 | 2.1% |
| 12 | CITADEL ADVISORS LLC | 1,676,344 | $23,234,128 | 1.7% |
| 13 | VANGUARD PORTFOLIO MANAGEMENT LLC | 1,457,629 | $20,202,738 | 1.4% |
| 14 | Hood River Capital Management LLC | 1,412,516 | $19,577,472 | 1.4% |
| 15 | RENAISSANCE TECHNOLOGIES LLC | 1,408,925 | $19,527,701 | 1.4% |
Manager names and figures are transcribed from each manager's own Form 13F information table. A manager listing shares in this snapshot does not mean it holds them today.
Reported change, 2026-03-31 to 2026-06-30
| Quarter ended | Filed through | Reporting managers | Reported shares | Value as filed |
|---|---|---|---|---|
| 2026-03-31 | 2026-05-29 | 254 | 94,184,489 | $1,427,864,922 |
| 2026-06-30 | 2026-08-31 | 268 | 101,583,226 | $1,347,826,550 |
Every change figure on this page is a reported quarter-over-quarter change between filing snapshots. It is not real-time trading activity.
AMPX reported totals over time
Quarter ended 2026-06-30: 268 reporting managers · 101,583,226 reported shares · $1,347,826,550 value as filed.
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Quarter-end 13F filed data, long positions only; filings arrive up to 45 days after quarter end.
CUSIPs behind the AMPX total
The validated bridge mapped 2 current CUSIP(s) to AMPX for this quarter: 03214Q108, 03214Q116. Option pseudo-CUSIPs, units, warrants, and preferred classes are excluded from these common-share totals. Mapping coverage in this publication set: 4562 of 6046 universe tickers have at least one validated CUSIP mapping (75.5%). Latest-quarter filed value resolved to any listed ticker: 77.3%; resolved to this universe: 77.2%.
What this page is and is not
Form 13F reports are quarterly holdings snapshots. Managers file up to about 45 days after quarter-end, so these figures describe reported positions as of the quarter-end date, not holdings today. 13F lists reportable long positions from managers above the SEC reporting threshold and omits short positions entirely.
This page is informational only. It is not investment advice, a recommendation, or a signal to buy or sell. Source: SEC Form 13F bulk data set for filings through 2026-08-31 (period ended 2026-06-30), joined to tickers through StockEyes' validated CUSIP bridge. Methodology and coverage are documented on the institutional ownership hub.
Insider transactions for AMPX (officer and director buys and sells) are covered by InsiderTrace: insidertrace.com/stock/ampx. StockEyes does not duplicate insider transaction tables.
Related StockEyes pages
Latest headlines tagged AMPX are on the market news wire. Upcoming earnings and market dates are on the events calendar. The term itself is defined in the institutional investor glossary entry, and the research workflow behind pages like this one is walked through in how to research a stock and how to compare SEC filings.