Stefan Constantin Ionel Insider Trading Activity

Corporate InsiderCTO · CIK 1940928

9

Total trades

$10.5M

Total volume

May 21, 2026

Last activity

AMPX

Amprius Technologies, Inc.

Stefan Constantin Ionel has been net-selling over the last 12 months with 0 purchases and 9 sales across 1 company.

AMPX is the most-traded position with 9 trades. The largest single transaction was a sale of AMPX for $5.9M on Jan 22, 2026.

Performance Scorecard

Forward stock performance after each transaction by Stefan Constantin Ionel. Buy returns measure price movement after open-market purchases; sell-avoided measures the loss avoided after open-market sales. Success rate counts trades where the insider's direction was right.

PERIODAVG BUY RETURNAVG SELL AVOIDEDSUCCESS RATETRADES
30 days-8.1%78%9
90 days-65.7%0%8
120 days-51.0%0%8

Performance based on stock price movement after each transaction date. Past results do not predict future returns. Not financial advice.

Price & Trades

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AMPX · Amprius Technologies, Inc.

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Recent Trades

DATETICKERTYPESHARESPRICEVALUEΔ OWNEDROLEFILING
May 21, 2026
Filed 3d late
AMPXSell28,812$14.79$426K−3.5%CTO
Feb 23, 2026
AMPXSell25,366$10.16$258K−3.4%CTO
Jan 28, 2026
AMPXSell39,690$12.00$476K−5.0%CTO
Jan 23, 2026
AMPXSell1,600$12.00$19K−0.2%CTO
Jan 22, 2026
AMPXSell492,827$12.04$5.9M−39.7%CTO
Jan 21, 2026
AMPXSell73,280$12.00$879K−8.9%CTO
Dec 11, 2025
AMPXSell198,255$10.51$2.1M−20.9%CTO
Nov 21, 2025
AMPXSell25,024$10.08$252K−3.0%CTO
Aug 21, 2025
AMPXSell19,159$6.82$131K−2.2%CTO

Top Companies Traded

TICKERCOMPANYTRADESTOTAL VOLUME
AMPXAmprius Technologies, Inc.9$10.5M

Other insiders at Amprius Technologies, Inc.

2 other tracked filers at AMPX.