SEC Form 4 reporting owner

Stepien Thomas M

Stepien Thomas M has filed 11 Form 4 transactions reported between December 19, 2025 and August 25, 2026, as Chief Executive Officer, President of Amprius Technologies, Inc..

Name as filed: Stepien Thomas M

Open-market buys, 24 mo
None
reported
Open-market sales, 24 mo
$1.3M
5 lines
Companies
1
with Form 4 filings
Latest transaction
Aug 25, 2026
transaction date

Roles and reported holdings

  • AMPXAmprius Technologies, Inc.
    Dec 19, 2025 – Aug 25, 2026

    Chief Executive Officer, President

    Held directly578,750 sh as of Aug 25, 2026 · Form 4

    24 months: $1.3M sold

Transaction history

All 11 reported transactions, newest first. Every row links to the Form 4 on SEC EDGAR.

DateCompanyTypeSharesValueFiling
Aug 25, 2026AMPXChief Executive OfficerGiftCode G · direct346—Form 4
Aug 25, 2026AMPXChief Executive OfficerGiftCode G · direct5,000—Form 4
Aug 24, 2026AMPXChief Executive OfficerOpen-market saleCode S · direct8,000$80K@ $10.03Form 4
Aug 21, 2026AMPXChief Executive OfficerOpen-market saleCode S · direct23,529$243K@ $10.34Form 4
Jun 4, 2026AMPXChief Executive OfficerOpen-market saleCode S · direct2,000$42K@ $20.97Form 4
Jun 4, 2026AMPXChief Executive OfficerGiftCode G · direct36,914—Form 4
Jun 4, 2026AMPXChief Executive OfficerGiftCode G · direct30,384—Form 4
May 27, 2026AMPXChief Executive OfficerOpen-market saleCode S · direct4,375$75K@ $17.19Form 4
May 21, 2026AMPXChief Executive OfficerOpen-market saleCode S · direct60,702$898K@ $14.79Form 4
Mar 4, 2026AMPXChief Executive OfficerGrant or awardCode A · direct150,000—Form 4
Dec 19, 2025AMPXPresidentGrant or awardCode A · direct200,000—Form 4

How this page is built

Every row comes from a Form 4 filed with the SEC, which officers, directors and holders of more than 10% of a company’s stock must file within two business days of a trade. Transactions are grouped by the reporting owner’s name as filed (spacing, capitals and punctuation ignored); two different people filing under an identical name would appear together, and one person filing under two spellings appears on two pages.

Open-market totals count code P purchases and code S sales over the last 24 months. The same trade reported on more than one filing is counted once; when another owner (for example a fund and its general partner) reports the identical trade, they are listed beside it. Holdings are the shares owned after the latest purchase, sale, gift or tax-withholding line, shown separately for direct and indirect ownership; an indirect figure is one holding line, not a total across every trust or entity.

This page describes what was filed with the SEC; it is not investment advice or a recommendation to buy or sell any security.