Acm Research, Inc.
A maker of wet-cleaning machines that keep semiconductor chips free of tiny particles during manufacturing, sold largely to chip fabs in mainland China under technologies like SAPS, TEBO, and Tahoe. It also builds electroplating, furnace, and packaging tools. Founded in 1998 in Silicon Valley by Dr. David Wang, it pivoted from stress-free copper polishing to cleaning after early tools struggled commercially. Its name "ACM" originally stood for "Advanced Copper Materials," a nod to its first copper-polishing ambition.
Estimated from filings — the split-adjusted price range over the quarters each manager built the position. A range, not a fill price; 13F reports a quarter-end snapshot, not a trade date.