Company · Ownership research

Amprius Technologies, Inc. AMPX

CIK 0001899287

Form 4 transactions dated Sep 1, 2023 to Sep 25, 2026, as reported to the SEC.

Insider trading Initial holdings Institutional holders

Insider filings on file run through 2026-08-25.

Insider purchases & sales

Purchased: $0.00
Sold: $97.47M

Sep 1, 2023 – Aug 25, 2026
Available records · partial months are marked ·

2023, from Sep 1, 202310 of 26 preview events

Date	Insider	Activity	Trade value (USD)	% of prior holding
2023-12-15	Amprius, Inc. 10% owner	Sale	$353.60K 100,000 shares sold	0.15% sold Direct holding	▾
2023-12-14	Amprius, Inc. 10% owner	Sale	$354.80K 100,000 shares sold	0.15% sold Direct holding	▾
2023-12-14	MIRRO JUSTIN E Director	Sale	$907.45K 255,000 shares sold	Unavailable Indirect holding	▾
2023-12-13	Amprius, Inc. 10% owner	Sale	$361.69K 100,000 shares sold	0.15% sold Direct holding	▾
2023-12-13	MIRRO JUSTIN E Director	Sale	$331.12K 90,000 shares sold	Unavailable Indirect holding	▾
2023-12-12	MIRRO JUSTIN E Director	Sale	$228.79K 60,000 shares sold	Unavailable Indirect holding	▾
2023-12-07	Bornstein Jonathan President of Amprius Lab	Sale10b5-1 footnote	$211.34K 54,477 shares sold	100.00% sold Direct holding	▾
2023-12-07	MIRRO JUSTIN E Director	Sale	$116.45K 30,000 shares sold	Unavailable Indirect holding	▾
2023-12-06	Bornstein Jonathan President of Amprius Lab	Sale10b5-1 footnote	$192.24K 47,767 shares sold	100.00% sold Direct holding	▾
2023-12-06	MIRRO JUSTIN E Director	Sale	$121.42K 30,000 shares sold	Unavailable Indirect holding	▾

Showing 26 / 26 record groups in 2023. The complete set is available through the API.

Amprius Technologies, Inc. · AMPX

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The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. For the year shown, this page lists 26 of 26 purchase / sale groups and 26 of 26 other groups; the totals and the monthly series cover the whole window.

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{"ticker":"AMPX","transaction_code":["P","S"],"transaction_form_type":"4","page_size":20}

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Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.

Non-cancelled, non-derivative purchase (P) and sale (S) rows dated inside the public window, as reported. Includes open-market and private transactions. Data after the latest filing is not asserted complete and is not zero-filled. A grouped event shares filing, transaction date, security, code, direction, ownership bucket and source. Derivative groups also match underlying security, exercise price, exercise/expiration dates and footnote references. Reported rows are retained; P/S price lots can be grouped. Post-transaction balances are never summed.