SEC Form 4 · accession 0001140361-26-033892
ACM Research, Inc. · ACMR
Statement of changes in beneficial ownership, as filed. Original on EDGAR ↗
Reporting owner
Haiping Dun
Director
Period of report
Aug 18, 2026
Accepted (ET)
Aug 20, 2026 · 4:30 pm EDT
Rule 10b5-1 plan
yes — trade under a plan
Issuer CIK
0001680062
Table I — non-derivative securities
| Security | Date | Code | Shares | Price | A/D | Owned after | D/I | Nature of ownership |
|---|---|---|---|---|---|---|---|---|
| Class A Common Stock | Aug 18, 2026 | M | 5,000 | $5.60 | A | 5,000 | D | |
| Class A Common StockF2 | Aug 18, 2026 | S | 1,200 | $80.29 | D | 3,800 | D | |
| Class A Common StockF3 | Aug 18, 2026 | S | 3,400 | $81.31 | D | 400 | D | |
| Class A Common StockF4 | Aug 18, 2026 | S | 400 | $82.17 | D | 0 | D | |
| Class A Common Stock | holding | — | — | — | 100,000 | I | Dun Family GST Trust | |
| Class A Common Stock | holding | — | — | — | 755,090 | I | Haiping Dun & Chi-Pin H Dun Revocable Trust |
Table II — derivative securities
| Security | Conv. / exercise price | Date | Code | Shares | A/D | Exercisable | Expires | Underlying | Underlying shares | Owned after | D/I |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Stock OptionF5 | $5.60 | Aug 18, 2026 | M | 5,000 | D | — | Apr 22, 2029 | Class A Common Stock | 5,000 | 45,000 | D |
Explanation of responses
- F1The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 13, 2025.
- F2The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $79.89 to $80.77, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (2), (3), and (4) to this Form 4.
- F3The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $80.95 to $81.91, inclusive.
- F4The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $81.97 to $82.33, inclusive.
- F5The option is fully vested and exercisable.