Chu Steven
Director · AMPX
As of 2026-09-16, Chu Steven has 12 Form 4 transactions on record across 1 company — 11 in the trailing 12 months.
Everything this person has disclosed to the SEC on Form 4 — across every company they file for — reconstructed from the public record. A filing history, not a tip sheet.
Reconstructed holdings
- Direct $1.3M
- Indirect $0
| AMPX | direct | 137,762 sh | $1.3M |
Reconstructed from this person's own Form 4 filings — the total each filing reported owning afterward, priced at the close on the as-of date shown. A filed position can lag the real one.
Direct and indirect holdings (e.g. through a trust or fund) are tagged separately, as filed.
Trades by company
Filing ledger
| Date | Company | Action | Shares @ price | Value | Ownership Δ | Owned after | Filing |
|---|---|---|---|---|---|---|---|
| 2026-03-12 | AMPX | Sale | 100,000 @ $18.65 | $1.9M | −35.3% of holding | 182,904 | Form 4 |
| 2026-03-12 | AMPX | Sale | 50,000 @ $18.21 | $911K | −27.3% of holding | 132,904 | Form 4 |
| 2026-03-12 | AMPX | Sale | 5,565 @ $18.53 | $103K | −4.2% of holding | 127,339 | Form 4 |
| 2026-03-10 | AMPX | Sale | 166,632 @ $17.92 | $3.0M | −56.7% of holding | 127,339 | Form 4 |
8 award / exercise / gift records — not counted as purchases
| Date | Company | Action | Shares | Owned after | Filing |
|---|---|---|---|---|---|
| 2026-06-12 | AMPX | Award / grant | 10,423 | 137,762 | Form 4 |
| 2026-03-12 | AMPX | Option exercise | 86,143 | 213,482 | Form 4 |
| 2026-03-12 | AMPX | Option exercise | 86,143 | 184,108 | Form 4 |
| 2026-03-12 | AMPX | Option exercise | 69,422 | 0 | Form 4 |
| 2026-03-12 | AMPX | Option exercise | 69,422 | 282,904 | Form 4 |
| 2026-03-10 | AMPX | Option exercise | 104,132 | 69,422 | Form 4 |
| 2026-03-10 | AMPX | Option exercise | 104,132 | 293,971 | Form 4 |
| 2025-06-13 | AMPX | Award / grant | 44,444 | 189,839 | Form 4 |
Source: SEC Form 4 filings. Each row links to its original filing.
Research tool, not investment advice — historical frequencies, not recommendations. A product of Marovel Technologies LLC. Full terms.