ACM Research, Inc. — Director's Dealing 2025

Oct 29, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: ACM Research, Inc. (ACMR)
CIK: 0001680062
Period of Report: 2025-10-27

Reporting Person: Wang David H (N/A)

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2025-10-27	Stock Option	$7.36	A	545400	Acquired	2030-03-19	Class A Common Stock (545400)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Class A Common Stock	100002	Indirect
Class A Common Stock	45837	Indirect
Class A Common Stock	180000	Indirect
Class A Common Stock	620001	Indirect

Footnotes

F1: On March 20, 2020, the reporting person was granted options to purchase an aggregate of 1,636,197 shares of the Issuer's Class A common stock, based on the satisfaction of certain performance criteria. In general, one-third of the shares subject to the options vest and become exercisable upon an increase in the Issuer's market capitalization (calculated as described in footnote 2) of $1 billion, $2 billion and $3 billion, respectively, from the market capitalization of $553,383,586 on the date of grant. 545,400 shares vested and became exercisable on October 27, 2025, which was the first trading day as of which the Issuer's market capitalization equaled or exceeded $2,553,383,586. The remaining shares will vest and become exercise upon the first trading days, if any, on which the Issuer's market capitalization equals or exceeds $3,553,383,586.

F2: For purposes of the options, the market capitalization as of a specified trading day is calculated by multiplying (a) the average of the daily volume-weighted average price per share of the Issuer's Class A common stock for each of the trading days occurring during the thirty calendar day period ending on that specified trading day by (b) the total number of issued and outstanding shares of the Issuer's Class A and Class B common stock as of 11:59 p.m. (Eastern time) on such specified trading day.