ACM Research, Inc.
US ˙ NasdaqGM ˙ US00108J1097

SecurityACMR / ACM Research, Inc.
InstitutionDiametric Capital, LP
Latest Disclosed Ownership8,555 shares
Latest Disclosed Value $ 336,639
Diametric Capital, LP reports 75.58% decrease in ownership of ACMR / ACM Research, Inc.

On May 15, 2026 - Diametric Capital, LP filed a 13F-HR form disclosing ownership of 8,555 shares of ACM Research, Inc. (US:ACMR) valued at $336,639 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 35,029 shares of ACM Research, Inc.. This represents a change in shares of -75.58% during the quarter. The current value of the position is $760,197 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)
2026-05-15 2026-03-31 13F ACM RESH COM CL A 00108J109 8,555 -26,474 -75.58 337 -75.67 0.0875
2026-02-13 2025-12-31 13F ACM RESH COM CL A 00108J109 35,029 27,423 360.54 1,382 364.98 0.3704
2025-11-13 2025-09-30 13F ACM RESH COM CL A 00108J109 7,606 -2,003 -20.85 298 19.76 0.1104
2025-08-13 2025-06-30 13F ACM RESH COM CL A 00108J109 9,609 -3,307 -25.60 249 -17.61 0.1328
2025-05-14 2025-03-31 13F ACM RESH COM CL A 00108J109 12,916 12,916 301 0.3585
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.