ACM Research, Inc.
ACM Research, Inc. (ACMR) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · ACMR · as of Sep 30, 2025
Ownership Breakdown
286
Institutional Holders
▲ 19 vs Q2
$1.63B
Total Inst. Value
▲ $665.18M vs Q2
64.12M
Shares Outstanding
freeFloat 90.19%
41.78M
13F Shares Held
▲ 4.35M vs Q2
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
ACMR largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
BLACKROCK, INC. special industry machinery, nec | 7.59M | 11.86% | 11.86% | $296.90B | Nov 12, 2025 | ▲ 3.48M |
VANGUARD GROUP INC special industry machinery, nec | 4.85M | 7.58% | 7.58% | $189.64B | Nov 7, 2025 | ▲ 550.0K |
LSV ASSET MANAGEMENT special industry machinery, nec | 2.50M | 3.91% | 3.91% | $97.99B | Nov 6, 2025 | ▲ 2.06M |
TRIATA CAPITAL LTD special industry machinery, nec | 2.00M | 3.13% | 3.13% | $78.39B | Nov 13, 2025 | ▲ 413.0K |
STATE STREET CORP special industry machinery, nec | 1.99M | 3.11% | 3.11% | $77.88B | Nov 14, 2025 | ▲ 735.6K |
SOUTHEASTERN ASSET MANAGEMENT INC/TN/ special industry machinery, nec | 1.49M | 2.32% | 2.32% | $58.13B | Nov 14, 2025 | ▲ 299.9K |
MITSUBISHI UFJ TRUST & BANKING CORP special industry machinery, nec | 1.36M | 2.13% | 2.13% | $53.22B | Oct 31, 2025 | ▼ 942.4K |
GEODE CAPITAL MANAGEMENT, LLC special industry machinery, nec | 1.32M | 2.07% | 2.07% | $51.80B | Nov 12, 2025 | ▲ 85.5K |
PEAK6 LLC special industry machinery, nec | 1.28M | 2.00% | 2.00% | $50.18B | Mar 31, 2026 | ▲ 776.4K |
FEDERATED HERMES, INC. special industry machinery, nec | 1.06M | 1.66% | 1.66% | $41.53B | Nov 3, 2025 | ▼ 360.5K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q3 2025 vs prior quarter
Q3 2025
28
Increased
+11.00M shares6
New Positions
first time holders14
Decreased
−3.08M shares0
Sold Out
fully exitedNet shares change (top 50)
+7.92M
+11.00M / −3.08M
Net new holders
+20
6 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
ACMR insider trading · insider activity
Source: SEC Form 4
Insiders have been primarily selling shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
6
Buy transactions
29
Sell transactions
0.21
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
Cheav Sotheara See remarks | Jun 4, 2026 | Sale | 1,300 | $84.08 | $109.3K | 112.1K | Form 4 ↗ |
Cheav Sotheara See remarks | Jun 5, 2026 | Sale | 2,384 | $81.73 | $194.8K | 103.0K | Form 4 ↗ |
Cheav Sotheara See remarks | Jun 4, 2026 | Sale | 9,212 | $85.11 | $784.0K | 102.8K | Form 4 ↗ |
Cheav Sotheara See remarks | Jun 5, 2026 | Sale | 968 | $82.61 | $80.0K | 102.0K | Form 4 ↗ |
Cheav Sotheara See remarks | Jun 5, 2026 | Sale | 400 | $84.01 | $33.6K | 101.6K | Form 4 ↗ |
Cheav Sotheara See remarks | Jun 4, 2026 | Sale | 2,839 | $85.77 | $243.5K | 100.0K | Form 4 ↗ |
Cheav Sotheara See remarks | Jun 5, 2026 | Sale | 1,647 | $85.41 | $140.7K | 100.0K | Form 4 ↗ |
Wang David H See Remarks | Jun 3, 2026 | Sale | 4,300 | $87.57 | $376.6K | 858.4K | Form 4 ↗ |
Wang David H See Remarks | Jun 3, 2026 | Sale | 6,295 | $88.98 | $560.1K | 852.1K | Form 4 ↗ |
Wang David H See Remarks | Jun 4, 2026 | Sale | 2,060 | $83.86 | $172.8K | 840.6K | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
ACM Research, Inc. (ACMR) is primarily owned by institutional investors, who hold approximately 65.2% of total shares outstanding. Company insiders own approximately 9.81%, while retail and public investors account for the remaining 25.03%.
The largest institutional shareholder of ACM Research, Inc. is BLACKROCK, INC., holding approximately 7.59 million shares — equal to 11.86% of outstanding shares — as of September 30, 2025.
A total of 286 institutional investors currently hold ACMR stock, with a combined institutional value of approximately $1.63 billion as of the most recent 13F filing period.
Frequently asked questions
ACMR ownershipACM Research, Inc. (ACMR) is primarily owned by institutional investors, who hold approximately 65.2% of shares. The largest shareholder is BLACKROCK, INC. with a 11.86% stake. Company insiders hold 9.81%. Data sourced from SEC Form 13F as of September 30, 2025.