SCHEDULE 13G/A

ACM Research Inc

Ordinary shares, par value $0.01 per share · CUSIP: 00108J109

Event date: 2024-09-30

Reporting persons may disclose overlapping interests. Their amounts are shown individually and are not added into a filing total.

Filing-level shares

Unavailable

Percent of class

Unavailable

• Yiheng Capital Partners, L.P.

  Shares: 666,304.00 · Class: 1.2%

• Yiheng Capital, LLC

  Shares: 666,304.00 · Class: 1.2%

• Yiheng Capital Management, LP

  Shares: 666,304.00 · Class: 1.2%

• Yuanshan Guo

  Shares: 666,304.00 · Class: 1.2%

Amounts are as disclosed in this filing. Schedule type alone does not establish investment intent.