Charles C. Pappis - 05 Mar 2026 Form 4 Insider Report for ACM Research, Inc. (ACMR)

Role
Director
Signature
/s/ Mark McKechnie, Attorney-in-Fact for Charles Pappis
Issuer symbol
ACMR
Transactions as of
05 Mar 2026
Net transactions value
-$250,450
Form type
4
Filing time
09 Mar 2026, 16:30:32 UTC
Previous filing
14 Aug 2025

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Pappis Charles C Director C/O ACM RESEARCH, INC., 42307 OSGOOD ROAD, SUITE I, FREMONT /s/ Mark McKechnie, Attorney-in-Fact for Charles Pappis 09 Mar 2026 0001475345

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction ACMR Class A Common Stock Options Exercise +5,000 $29.18* 5,000 05 Mar 2026 Direct F1
transaction ACMR Class A Common Stock Sale $250,450 -5,000 -100% $50.09 0 05 Mar 2026 Direct F2

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction ACMR Stock Option Options Exercise -5,000 -50% $0.000000* 5,000 05 Mar 2026 Class A Common Stock 5,000 $29.18 Direct F1, F3
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Buy Plan / Sale Plan: These are also open market purchases/sales of shares, but in this case the transaction is part of a trading plan. Rule 10b5-1 allows insiders to setup a trading plan to buy/sell stocks over a certain period of time. Since the purchases/sales are predetermined, this protects the insiders from violating insider trading law.

Transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c).

Explanation of Responses:

Id Content
F1 On March 5, 2026, the reporting person exercised a previously issued stock option to purchase 5,000 shares of Class A Common Stock of the Issuer.
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.
F3 The option is fully vested and exercisable.