Steven Chu

CIK 1296381 · last filed 2026-03-12

Steven Chu is a corporate insider who has filed 8 SEC Form 4 insider transactions across 2 companies since 2022. The most recent filing, for AMPX.WS, was dated Mar 12, 2026. Across all open-market trades the lifetime net is −$5.9M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $943.6K across reported positions.

"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

$943.6K

Companies

2

Total Filings

8

Lifetime Open-Market Net

-$5.86M

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 Director 132,904 $7.10 $943.6K -$5.86M 5 2026-03-12
Zymergen Inc. (ZY) Delisted Director 0 $2.43 $0 $0 2 2022-10-19

Recent Filings

8 filings
Form 4 transactions across all companies, newest first.
Filed Symbol Action Net Shares Net $ Link
2026-03-12 AMPX.WS Mixed −62,500 -$5.53M EDGAR
2025-06-17 AMPX.WS Grant (A) +44,444 $0 EDGAR
2024-10-25 AMPX.WS Grant (A) $0 EDGAR
2024-06-07 AMPX.WS Grant (A) +125,000 $0 EDGAR
2023-06-12 AMPX.WS Grant (A) +17,895 $0 EDGAR
2022-10-19 Zymergen Inc. (ZY) Delisted Disp (D) −50,000 $0 EDGAR
2022-09-16 Grant (A) $0
2022-06-06 Zymergen Inc. (ZY) Delisted Grant (A) +50,000 $0 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.