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Public ownership evidence

Amprius Technologies, Inc. (AMPX) Ownership Disclosures

Read AMPX insider transactions, institutional 13F filings and Congressional disclosures with report dates, public availability and original receipts.

As of 2026-10-14T23:32:50.005Z

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2026-08-262026-08-25Stepien Thomas MA346Not reported

First displayed source row from Recent Form 4 activity. The full bounded history and coverage notes remain below.

The displayed observation date is 2026-08-25 and its public availability date is 2026-08-26. Subtracting those calendar dates gives 1 day of disclosure lag. Historical public research can use the record from the availability date, rather than backdating knowledge to the observation date. The calendar-day difference does not assert an intraday publication time.

This row is code A: a award. An award is an acquisition but is not an open-market purchase. A purchase-following rule must not count it as code P.

Open the linked original receipts to verify the row, then inspect a second record before drawing a pattern. This public filing observation supplies source evidence, not a completed copy-trading return.

SEC 0002067233-26-000019 ↗SEC 0002067233-26-000019 ↗SEC 0002067233-26-000019 ↗

Recent Form 4 activity

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2026-08-262026-08-25Stepien Thomas MA346Not reported
2026-08-262026-08-24Stepien Thomas MS8,000Not reported
2026-08-262026-08-21Stepien Thomas MS23,529Not reported
2026-08-262026-08-21Stefan Constantin IonelS29,681Not reported
2026-08-262026-08-21Sun KangS62,101Not reported

90-day public availability window, up to 50 records.

Recent institutional filing receipts

Inspect all 50 displayed rows: Recent institutional filing receipts

These are raw ticker-matched positions in recent 13F receipts, including amendments. They are not deduplicated current ownership totals. Open the manager profile to inspect its effective filing book.

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Cornerstone Financial Management LLC2026-06-302026-08-29205$2,841None
Cornerstone Financial Management LLC2026-03-312026-08-29205$3,456None
Cornerstone Financial Management LLC2025-12-312026-08-29205$1,617None
B. Riley Wealth Advisors, Inc.2025-03-312026-08-2946,500$124,620None
Corient Private Wealth LP2026-06-302026-08-2819,573$271,282None
CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM2026-06-302026-08-25141,264$1,957,919None
CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM2026-06-302026-08-251,957,919$141,264,000None
CANTOR FITZGERALD, L. P.2026-06-302026-08-20147,909$2,050,019None
MERCER GLOBAL ADVISORS INC /ADV2026-06-302026-08-2018,889$261,802None
Strive Financial Group ,LLC2026-06-302026-08-18775$10,742None
Corient Private Wealth LP2026-06-302026-08-1819,773$274,054None
CAPSTONE INVESTMENT ADVISORS, LLC2026-06-302026-08-1832,390$448,925None
DARK FOREST CAPITAL MANAGEMENT LP2026-06-302026-08-1554,128$750,214None
Graham Capital Management, L.P.2026-06-302026-08-1510,362$143,617None
SEI INVESTMENTS CO2026-06-302026-08-15442,750$6,136,515None
SEI INVESTMENTS CO2026-06-302026-08-15480$6,650None
Federation des caisses Desjardins du Quebec2026-06-302026-08-152,300$31,878None
Marex Group Ltd2026-06-302026-08-151,683$23,326None
Marex Group Ltd2026-06-302026-08-15125,000$1,732,500None
Marex Group Ltd2026-06-302026-08-15247$3,423None
Polymer Capital Management (US) LLC2026-06-302026-08-1538,444$532,834None
Nearwater Capital Markets, Ltd2026-06-302026-08-151,034,700$14,340,942None
EARNED WEALTH ADVISORS, LLC2026-06-302026-08-1512,416$172,086None
Hel Ved Capital Management Ltd2026-06-302026-08-1571,850$995,841None
XTX Topco Ltd2026-06-302026-08-15180,174$2,497,212None
Aquatic Capital Management LLC2026-06-302026-08-15189,235$2,622,797None
CHARLES SCHWAB INVESTMENT MANAGEMENT INC2026-06-302026-08-151,176,959$16,312,652None
Sixth Street Partners Management Company, L.P.2026-06-302026-08-151,176,959$16,312,652None
Foundations Investment Advisors, LLC2026-06-302026-08-15119,465$1,655,785None
ExodusPoint Capital Management, LP2026-06-302026-08-15179,272$2,484,710None
Qube Research & Technologies Ltd2026-06-302026-08-151,136,175$15,747,386None
OSAIC HOLDINGS, INC.2026-06-302026-08-152,452$33,985None
OSAIC HOLDINGS, INC.2026-06-302026-08-1546,756$648,004None
Squarepoint Ops LLC2026-06-302026-08-15119,800$1,660,428Call
Squarepoint Ops LLC2026-06-302026-08-1560,100$832,986Put
Squarepoint Ops LLC2026-06-302026-08-1569,211$959,264None
Trexquant Investment LP2026-06-302026-08-151,097,532$15,211,794None
MetLife Investment Management, LLC2026-06-302026-08-1580,714$1,118,696None
Engineers Gate Manager LP2026-06-302026-08-1515,857$219,778None
JANE STREET GROUP, LLC2026-06-302026-08-15962,343$13,338,074None
JANE STREET GROUP, LLC2026-06-302026-08-152,438,728$33,800,770None
JANE STREET GROUP, LLC2026-06-302026-08-154,621,100$64,048,446Put
JANE STREET GROUP, LLC2026-06-302026-08-151,312,700$18,194,022Call
LMR Partners LLP2026-06-302026-08-151,750,850$24,266,781None
Legal & General Group Plc2026-06-302026-08-1569,530$963,685None
Legal & General Group Plc2026-06-302026-08-1525,053$347,235None
Legal & General Group Plc2026-06-302026-08-1513,340$184,892None
SUSQUEHANNA INTERNATIONAL GROUP, LLP2026-06-302026-08-154,565,200$63,273,672Call
SUSQUEHANNA INTERNATIONAL GROUP, LLP2026-06-302026-08-152,581,200$35,775,432Put
SUSQUEHANNA INTERNATIONAL GROUP, LLP2026-06-302026-08-151,037,958$14,386,098None

90-day public filing window, up to 50 source positions.

Cornerstone Financial Management LLC ↗Cornerstone Financial Management LLC ↗Cornerstone Financial Management LLC ↗B. Riley Wealth Advisors, Inc. ↗Corient Private Wealth LP ↗CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM ↗CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM ↗CANTOR FITZGERALD, L. P. ↗MERCER GLOBAL ADVISORS INC /ADV ↗Strive Financial Group ,LLC ↗

Recent Congressional disclosures

No matching Congressional transactions were returned in this source preview.

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Bounded public source preview, up to 25 disclosed events.

How to read the disclosure dates

The tables report different things: insider transactions, institutional positions and Congressional transaction ranges. Read each table with its source dates and units. They cannot be added into a combined ownership percentage.

  1. Company insiders

    SEC Form 4 purchases, sales and awards report transactions and their public filing availability.

  2. Institutional managers

    13F reports disclose delayed quarter-end positions. They are not a record of trades between quarters.

  3. Congressional filers

    Periodic transaction reports disclose transaction dates and amount brackets. Public filing dates determine what researchers could know.

Institutional source directory ↗Congressional source directory ↗

Read the transaction codes

Awards use transaction code A, purchases P and sales S. An acquisition from an award is not the same as an open-market purchase. Joint filers may share a transaction. Use original receipts and availability dates to interpret the events.