Insider filing · AMPX
Constantin Ionel Stefan
Chief Technology Officer
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Amprius Technologies, Inc.
AMPX · Industrials · 29 filings in 24 months
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Constantin Ionel Stefan sold $252K of Amprius Technologies (AMPX)
Executed Nov 21 2025, disclosed Nov 25 2025, 4 days later.
Value, as filed
$252K
25,024 sh × $10.08
Executed
Nov 21 2025
the trade date, as filed
Disclosed
Nov 25 2025
4 days after the trade
Return, 21 sessionsiFrom the disclosed entry session; derived
–
purchases only
Returns are measured on stock purchases only.
The filer
CSConstantin Ionel Stefan (Chief Technology Officer) filed 7 Form 4 reports in the trailing twelve months (0 purchases, 7 sales), most often in Amprius Technologies, Inc. (AMPX). The largest single filing was $6.8M of AMPX (566,107 sh across 2 lots, as filed), executed Jan 21.
The name
AMPXIndustrials · Amprius Technologies, Inc. develops, manufactures, and markets lithium-ion batteries for mobility applications
More Industrials filings→ Insider filings, newest first→ View the original filing at www.sec.gov→Other filings by Constantin Ionel Stefan in AMPX
AMPXSALE
Amprius Technologies, Inc.
$307K29,681 sh × $10.34
Exec Aug 21
Filed Aug 25 · 5:22 PM ET AMPXSALE Amprius Technologies, Inc. $426K
28,812 sh × $14.79
Exec May 21
Filed May 26 · 5:30 PM ET AMPXSALE Amprius Technologies, Inc. $258K
25,366 sh × $10.16
Exec Feb 23
Filed Feb 24 · 5:30 PM ET AMPXSALE Amprius Technologies, Inc. $476K
39,690 sh × $12.00
Exec Jan 28
Filed Jan 30 · 5:30 PM ET AMPXSALE Amprius Technologies, Inc. $6.8M
566,107 sh across 2 lots
Exec Jan 21
Filed Jan 23 · 5:30 PM ET AMPXSALE Amprius Technologies, Inc. $2.1M
198,255 sh × $10.51
Exec Dec 11 2025
Filed Dec 15 2025 · 5:30 PM ET AMPXSALE Amprius Technologies, Inc. $131K
19,159 sh × $6.82
Exec Aug 21 2025
Filed Aug 25 2025 · 5:30 PM ET