Cheav Sotheara 4

What Happened
Cheav Sotheara, Senior Vice President, Manufacturing (ACM Research (Shanghai) subsidiary), exercised a total of 18,750 options (fully vested) at $13.89 per share on June 4–5, 2026 (cost ≈ $260,437) and sold the resulting 18,750 shares in multiple open‑market transactions the same days for aggregate proceeds of about $1,585,922. The sales were executed pursuant to a Rule 10b5‑1 trading plan adopted March 5, 2026.

Key Details

• Exercise dates and amounts: 13,351 shares exercised on 2026-06-04 ($185,445) and 5,399 shares exercised on 2026-06-05 ($74,992). (Options fully vested — F9.)
• Sales: 18,750 shares sold across 6/4–6/5 at weighted‑average prices reported; total proceeds ≈ $1,585,922. Reported sale price ranges across transactions: roughly $81.22–$86.19 (see footnotes F2–F8 for per‑range details).
• Plan/footnotes: Sales effected under a 10b5‑1 plan (F1). Several sale line items use weighted‑average prices; the filer will provide per‑trade price breakdown on request (F2–F8).
• Shares owned after transaction: Not disclosed in the provided filing excerpt.
• Timeliness: Report filed 2026-06-05 for transactions reported 2026-06-04–06-05 (filed timely).

Context
This was an option exercise followed by immediate open‑market sales (a common cashless outcome when executives exercise vested options). The use of a 10b5‑1 plan means the sales were pre‑arranged and typically not ad hoc. Such transactions realize gains for the insider but, by themselves, do not necessarily indicate a change in the insider’s view of the company.