InsiderTrades

Form 4 for ACMR ACM Research, Inc.

Accepted 2026-04-21 16:30:08 ET · period of report 2026-04-17 · accession 0001140361-26-015915 · SEC index · Original document

Summary rows

Aggregated the way they appear in lists: one row per insider, transaction code and security table.

X Filed Traded Ticker Insider Title Type Price Qty Owned ΔOwn Value
DT 2026-04-21 16:30 2026-04-17 ACMR Pappis Charles C Dir M - OptEx $29.18 +5,000 5,000 New +$145.9K
DT 2026-04-21 16:30 2026-04-17 ACMR Pappis Charles C Dir S - Sale+OE $52.00 -5,000 0 -100% -$260.0K
DT 2026-04-21 16:30 2026-04-17 ACMR Pappis Charles C Dir M - OptEx $0.00 -5,000 0 -100% $0

Purchase Sale Sale after option exercise All abbreviations

Every reported transaction

#TableSecurityDateCodeA/DSharesPriceOwned afterOwnExercise / expiryUnderlyingFootnotes
1 Common Class A Common Stock 2026-04-17 M A 5,000 $29.18 5,000 D — — (F1) On April 17, 2026, the reporting person exercised a previously issued stock option to purchase 5,000 shares of Class A Common Stock of the Issuer.
2 Common Class A Common Stock 2026-04-17 S D 5,000 $52.00 0 D — — (F2) The sale reported on this Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on November 20, 2025.
3 Derivative Stock Option 2026-04-17 M D 5,000 $0.00 0 D $29.18 · — to 2035-03-14 5,000 Class A Common Stock (F1) On April 17, 2026, the reporting person exercised a previously issued stock option to purchase 5,000 shares of Class A Common Stock of the Issuer. (F3) The option is fully vested and exercisable.