SCHEDULE: Vanguard Group Maintains 8.3% Stake in ACM Research

The Vanguard Group has filed an amendment to its Schedule 13G, reporting an 8.3% beneficial ownership in ACM Research Inc. common stock as of December 31, 2025.

Summary

• The Vanguard Group beneficially owns 4,972,103 shares of ACM Research Inc. common stock.
• This represents 8.3% of the class of securities.
• Vanguard holds shared voting power over 408,800 shares and shared dispositive power over all 4,972,103 shares.
• An internal realignment at The Vanguard Group, effective January 12, 2026, means it no longer performs portfolio management or administers proxy voting directly.
• Certain Vanguard subsidiaries or business divisions will now report beneficial ownership separately on a disaggregated basis.
• The securities were acquired and are held in the ordinary course of business, not for influencing control of ACM Research Inc.

Sentiment

Score: 7

Explanation: StockSavvy.ai views this filing as moderately positive, primarily because a major institutional investor like Vanguard maintains a significant stake, signaling continued confidence in ACM Research Inc. The internal realignment at Vanguard is a procedural change for the reporting entity, not a reflection on the issuer's performance.

Positives

• A major institutional investor like The Vanguard Group maintaining a significant 8.3% stake in ACM Research Inc. can be viewed as a vote of confidence in the company's long-term prospects.
• The holding is for investment purposes in the ordinary course of business, indicating no intent to disrupt company operations or control.

Negatives

• The filing itself does not contain explicitly negative information regarding ACM Research Inc.
• The internal realignment at Vanguard means future filings might show a disaggregated ownership, which is a structural change for Vanguard, not a negative for ACM Research.

Future Outlook

The Vanguard Group anticipates that certain subsidiaries or business divisions will report beneficial ownership separately on a disaggregated basis following an internal realignment effective January 12, 2026. These subsidiaries will continue to pursue the same investment strategies.

Management Comments

• The Vanguard Group, Inc. anticipates that certain subsidiaries or business divisions of subsidiaries of The Vanguard Group, Inc., that currently have, or are deemed to have, beneficial ownership with The Vanguard Group, Inc., will report beneficial ownership separately (on a disaggregated basis) from The Vanguard Group, Inc. in reliance on such release.
• These subsidiaries and/or business divisions pursue the same investment strategies as previously pursued by The Vanguard Group, Inc. prior to the realignment.
• The securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities.

Industry Context

StockSavvy.ai notes that institutional filings like this Schedule 13G provide transparency into significant ownership stakes, which can signal confidence from major asset managers in companies within the semiconductor equipment industry. While this filing primarily details Vanguard's internal structural changes, its continued substantial holding in ACM Research Inc. underscores ongoing institutional interest in the sector.

Stakeholder Impact

• Shareholders of ACM Research Inc.: The continued significant ownership by The Vanguard Group may reassure existing shareholders and attract new investors, indicating institutional confidence.
• Clients of The Vanguard Group: The internal realignment will result in disaggregated reporting, but the underlying investment strategies for these clients remain the same.

Next Steps

• The Vanguard Group's subsidiaries or business divisions are expected to report beneficial ownership separately on a disaggregated basis in future filings.

Key Dates

Recommendation

The filing indicates a stable, significant institutional holding by The Vanguard Group, which is generally a positive signal. However, it does not provide new operational or financial data about ACM Research Inc. that would warrant a change in investment thesis. The internal realignment at Vanguard is procedural and does not reflect on ACM Research's fundamentals. Therefore, a 'hold' recommendation is appropriate, maintaining current positions based on existing company fundamentals rather than this ownership update alone.

Keywords

ACM Research Inc, Vanguard Group, Common Stock, Institutional Ownership, Schedule 13G, Beneficial Ownership, Investment Adviser, Semiconductor Equipment