Constantin Ionel Stefan, the Chief Technology Officer of $AMPX, sold 28,812 shares of the company on 05-21-2026 for an estimated $426,083. We received data on the trade from a recent SEC filing. This was a sale of approximately 3.5% of their shares of this class of stock. Following this trade, they now own 804,518 shares of this class of $AMPX stock.
$AMPX Insider Trading Activity
$AMPX insiders have traded $AMPX stock on the open market 22 times in the past 6 months. Of those trades, 0 have been purchases and 22 have been sales.
Here’s a breakdown of recent trading of $AMPX stock by insiders over the last 6 months:
- KANG SUN has made 0 purchases and 8 sales selling 3,279,120 shares for an estimated $44,684,567.
- CONSTANTIN IONEL STEFAN (Chief Technology Officer) has made 0 purchases and 7 sales selling 859,830 shares for an estimated $10,073,945.
- WEN HSUAN HSIEH has made 0 purchases and 2 sales selling 413,146 shares for an estimated $7,620,033.
- STEVEN CHU has made 0 purchases and 4 sales selling 322,197 shares for an estimated $5,863,983.
- THOMAS M STEPIEN (Chief Executive Officer) sold 60,702 shares for an estimated $897,685
To track insider transactions, check out Quiver Quantitative's insider trading dashboard. You can access data on insider stock transactions through the Quiver Quantitative API insider transaction endpoint.
$AMPX Hedge Fund Activity
We have seen 166 institutional investors add shares of $AMPX stock to their portfolio, and 108 decrease their positions in their most recent quarter.
Here are some of the largest recent moves:
- JANE STREET GROUP, LLC added 3,947,231 shares (+1849.5%) to their portfolio in Q1 2026, for an estimated $66,550,314
- TWO SIGMA INVESTMENTS, LP added 2,069,136 shares (+144.0%) to their portfolio in Q1 2026, for an estimated $34,885,632
- MASSACHUSETTS FINANCIAL SERVICES CO /MA/ added 2,024,760 shares (+inf%) to their portfolio in Q1 2026, for an estimated $34,137,453
- PRICE T ROWE ASSOCIATES INC /MD/ added 1,816,842 shares (+2254.8%) to their portfolio in Q1 2026, for an estimated $30,631,956
- SUSQUEHANNA INTERNATIONAL GROUP, LLP removed 1,602,330 shares (-94.7%) from their portfolio in Q1 2026, for an estimated $27,015,283
- DRIEHAUS CAPITAL MANAGEMENT LLC added 1,400,966 shares (+58.5%) to their portfolio in Q1 2026, for an estimated $23,620,286
- NORGES BANK added 1,304,838 shares (+inf%) to their portfolio in Q4 2025, for an estimated $10,295,171
To track hedge funds' stock portfolios, check out Quiver Quantitative's institutional holdings dashboard. You can access data on hedge funds moves and 13F filings through the Quiver Quantitative API 13F endpoint.
$AMPX Revenue
$AMPX had revenues of $28.5M in Q1 2026. This is an increase of 152.89% from the same period in the prior year.
You can track AMPX financials on Quiver Quantitative's AMPX stock page.
You can access data on AMPX stock through the Quiver Quantitative API.
$AMPX Analyst Ratings
Wall Street analysts have issued reports on $AMPX in the last several months. We have seen 1 firms issue buy ratings on the stock, and 0 firms issue sell ratings.
Here are some recent analyst ratings:
- Needham issued a "Buy" rating on 01/29/2026
To track analyst ratings and price targets for $AMPX, check out Quiver Quantitative's $AMPX forecast page.
$AMPX Price Targets
Multiple analysts have issued price targets for $AMPX recently. We have seen 5 analysts offer price targets for $AMPX in the last 6 months, with a median target of $20.0.
Here are some recent targets:
- Austin Bohlig from Needham set a target price of $20.0 on 03/10/2026
- Christopher Souther from B. Riley Securities set a target price of $22.0 on 03/09/2026
- Eric Stine from Craig-Hallum set a target price of $21.0 on 03/06/2026
- Derek Soderberg from Cantor Fitzgerald set a target price of $20.0 on 03/06/2026
- Chip Moore from Roth Capital set a target price of $20.0 on 03/06/2026
This article is not financial advice. See Quiver Quantitative's disclaimers for more information.
