ACM Research, Inc.
US ˙ NasdaqGM ˙ US00108J1097

SecurityACMR / ACM Research, Inc.
InstitutionSei Investments Co
Latest Disclosed Ownership58,445 shares
Latest Disclosed Value $ 2,305,436
Sei Investments Co reports 164.62% increase in ownership of ACMR / ACM Research, Inc.

On February 13, 2026 - Sei Investments Co filed a 13F-HR form disclosing ownership of 58,445 shares of ACM Research, Inc. (US:ACMR) valued at $2,305,655 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 13, 2025 disclosing 22,086 shares of ACM Research, Inc.. This represents a change in shares of 164.62% during the quarter. The current value of the position is $5,193,423 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-02-13 2025-12-31 13F ACM RESH COM CL A 00108J109 58,445 36,359 164.62 2,305 166.78 0.0023
2025-11-13 2025-09-30 13F ACM RESH COM CL A 00108J109 22,086 -5,921 -21.14 864 19.17 0.0009
2025-08-14 2025-06-30 13F ACM RESH COM CL A 00108J109 28,007 -21,011 -42.86 725 -36.57 0.0008
2025-05-14 2025-03-31 13F/A-1 ACM RESH COM CL A 00108J109 49,018 49,018 1,144 0.0015
2025-05-13 2025-03-31 13F ACM RESH COM CL A 00108J109 28,168 28,168 637 0.0007
2024-11-12 2024-09-30 13F ACM RESH COM CL A 00108J109 0 -21,736 -100.00 0 -100.00
2024-08-13 2024-06-30 13F ACM RESH COM CL A 00108J109 21,736 1,358 6.66 501 -15.51 0.0007
2024-05-07 2024-03-31 13F ACM RESH COM CL A 00108J109 20,378 -766 -3.62 593 43.58 0.0009
2024-02-14 2023-12-31 13F ACM RESH COM CL A 00108J109 21,144 -64,457 -75.30 413 -73.34 0.0007
2023-11-14 2023-09-30 13F ACM RESH COM CL A 00108J109 85,601 47,536 124.88 1,550 211.67 0.0028
2023-08-11 2023-06-30 13F ACM RESH COM CL A 00108J109 38,065 0 0.00 498 11.69 0.0009
2023-05-12 2023-03-31 13F ACM RESH COM CL A 00108J109 38,065 -10,646 -21.86 445 18.67 0.0008
2023-02-10 2022-12-31 13F ACM RESH COM CL A 00108J109 48,711 22,300 84.43 376 13.98 0.0008
2022-11-14 2022-09-30 13F ACM RESH COM CL A 00108J109 26,411 26,411 329 0.0007
2020-12-04 2020-09-30 13F/A-1 ACM RESEARCH COM CL A 00108J109 0 -7,514 -100.00 0 -100.00
2020-08-17 2020-06-30 13F/A-1 ACM RESEARCH COM CL A 00108J109 7,514 -6,360 -45.84 469 14.11 0.0015
2020-08-11 2020-06-30 13F ACM RESEARCH COM CL A 00108J109 7,514 -6,360 469 1,272.1875
2020-05-14 2020-03-31 13F ACM RESEARCH COM CL A 00108J109 13,874 13,874 411 0.0015
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.