Constantin Ionel Stefan
CIK 1940928 · Chief Technology Officer · last filed 2026-05-28
"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.
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Disclosed Exposure
$5.69M
Companies
1
Total Filings
23
Lifetime Open-Market Net
-$10.93M
Holdings By Company
Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
| Symbol | Role | Shares | Price | Disclosed Exposure | Lifetime OM Net | Filings | Latest Filed |
|---|---|---|---|---|---|---|---|
| AMPX.WS | Chief Technology Officer | 801,310 | $7.10 | $5.69M | -$10.93M | 22 | 2026-05-28 |
Recent Filings · Page 2 of 3
23 filingsForm 4 transactions across all companies, newest first.
| Filed | Symbol | Action | Net Shares | Net $ | Link |
|---|---|---|---|---|---|
| 2025-03-21 | AMPX.WS | Grant (A) | +461,540 | $0 | EDGAR |
| 2025-03-18 | AMPX.WS | Exer (M) | +3,471 | $3.4K | EDGAR |
| 2025-02-24 | AMPX.WS | Sell (S) | −9,066 | -$28.4K | EDGAR |
| 2024-11-22 | AMPX.WS | Sell (S) | −8,575 | -$16.8K | EDGAR |
| 2024-10-25 | AMPX.WS | Grant (A) | — | $0 | EDGAR |
| 2024-08-22 | AMPX.WS | Sell (S) | −8,800 | -$9.2K | EDGAR |
| 2024-05-24 | AMPX.WS | Sell (S) | −9,393 | -$12.6K | EDGAR |
| 2024-03-19 | AMPX.WS | Grant (A) | +374,570 | $0 | EDGAR |
| 2023-09-18 | AMPX.WS | Sell (S) | −80,000 | -$300.2K | EDGAR |
| 2023-09-12 | AMPX.WS | Exer (M) | +80,000 | $4.0K | EDGAR |
Codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.