ACM Research, Inc.
US ˙ NasdaqGM ˙ US00108J1097

SecurityACMR / ACM Research, Inc.
InstitutionCitadel Advisors Llc
ManagerKen Griffin
Latest Disclosed Ownership203,378 shares
Latest Disclosed Value $ 8,002,924
Citadel Advisors Llc ownership in ACMR / ACM Research, Inc.

On May 15, 2026 - Citadel Advisors Llc filed a 13F-HR form disclosing ownership of 203,378 shares of ACM Research, Inc. (US:ACMR) valued at $8,002,924 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 143,022 shares of ACM Research, Inc.. This represents a change in shares of 42.20% during the quarter. The current value of the position is $15,515,708 USD.

Citadel Advisors Llc has a history of taking positions in derivatives of the underlying security (ACMR) in the form of stock options. The firm currently holds call options representing 283,000 of underlying shares valued at $11,136,050 USD and put options representing 69,600 of underlying shares valued at $2,738,760 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

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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Institutional Put/Call Ratios
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In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

ACMR / ACM Research, Inc. Historical Put/Call Ratio
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 203,378 60,356 42.20 8,003 41.83 0.0011
2026-02-17 2025-12-31 13F ACM RESH COM CL A 00108J109 143,022 -251,947 -63.79 5,642 -63.49 0.0008
2025-11-14 2025-09-30 13F ACM RESH COM CL A 00108J109 394,969 190,945 93.59 15,455 192.49 0.0024
2025-08-14 2025-06-30 13F ACM RESH COM CL A 00108J109 204,024 -249,117 -54.98 5,284 -50.04 0.0009
2025-05-15 2025-03-31 13F ACM RESH COM CL A 00108J109 453,141 97,400 27.38 10,576 96.91 0.0020
2025-02-14 2024-12-31 13F ACM RESH COM CL A 00108J109 355,741 -129,874 -26.74 5,372 -45.51 0.0009
2024-11-14 2024-09-30 13F ACM RESH COM CL A 00108J109 485,615 -201,058 -29.28 9,858 -37.75 0.0019
2024-08-14 2024-06-30 13F ACM RESH COM CL A 00108J109 686,673 406,852 145.40 15,835 94.21 0.0032
2024-05-15 2024-03-31 13F ACM RESH COM CL A 00108J109 279,821 181,828 185.55 8,154 325.97 0.0016
2024-02-14 2023-12-31 13F ACM RESH COM CL A 00108J109 97,993 -52,598 -34.93 1,915 -29.79 0.0004
2023-11-14 2023-09-30 13F ACM RESH COM CL A 00108J109 150,591 -157,536 -51.13 2,726 -32.36 0.0006
2023-08-14 2023-06-30 13F ACM RESH COM CL A 00108J109 308,127 -552,802 -64.21 4,030 -59.99 0.0008
2023-05-15 2023-03-31 13F ACM RESH COM CL A 00108J109 860,929 515,526 149.25 10,073 278.22 0.0022
2023-02-14 2022-12-31 13F ACM RESH COM CL A 00108J109 345,403 271,166 365.27 2,663 187.89 0.0006
2022-11-14 2022-09-30 13F ACM RESH COM CL A 00108J109 74,237 74,237 925 0.0002
2022-08-15 2022-06-30 13F ACM RESH COM CL A 00108J109 0 -242,973 -100.00 0 -100.00
2022-05-16 2022-03-31 13F ACM RESH COM CL A 00108J109 242,973 142,975 142.98 5,027 -41.05 0.0010
2022-02-14 2021-12-31 13F ACM RESH COM CL A 00108J109 99,998 79,373 384.84 8,527 275.97 0.0017
2021-11-15 2021-09-30 13F ACM RESH Cmn 00108J109 20,625 -43,452 -67.81 2,268 -65.37 0.0005
2021-08-16 2021-06-30 13F ACM RESH COM CL A 00108J109 64,077 -62,368 -49.32 6,550 -35.88 0.0015
2021-05-21 2021-03-31 13F/A-1 ACM RESEARCH COM CL A 00108J109 126,445 109,169 631.91 10,215 627.56 0.0025
2021-05-17 2021-03-31 13F ACM RESEARCH COM CL A 00108J109 126,445 109,169 10,215 0.0025
2021-02-16 2020-12-31 13F ACM RESEARCH COM CL A 00108J109 17,276 -6,751 -28.10 1,404 -15.42 0.0004
2020-11-16 2020-09-30 13F ACM RESEARCH COM CL A 00108J109 24,027 2,959 14.04 1,660 26.33 0.0005
2020-08-14 2020-06-30 13F ACM RESEARCH Cmn 00108J109 21,068 -15,069 -41.70 1,314 22.80 0.0005
2020-05-15 2020-03-31 13F ACM RESEARCH Cmn 00108J109 36,137 -3,018 -7.71 1,070 48.20 0.0005
2020-02-14 2019-12-31 13F ACM RESEARCH Cmn 00108J109 39,155 -27,429 -41.19 722 -21.78 0.0003
2019-11-14 2019-09-30 13F ACM RESEARCH Cmn 00108J109 66,584 26,473 66.00 923 47.44 0.0004
2019-08-14 2019-06-30 13F ACM RESEARCH Cmn 00108J109 40,111 40,111 626 0.0003
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-15 2026-03-31 13F ACM RESH COM CL A Call 283,000 -5.60 11,136 -5.84 n/a n/a n/a
2026-02-17 2025-12-31 13F ACM RESH COM CL A Call 299,800 88.79 11,827 90.36 n/a n/a n/a
2025-11-14 2025-09-30 13F ACM RESH COM CL A Call 158,800 -29.52 6,214 6.48 n/a n/a n/a
2025-08-14 2025-06-30 13F ACM RESH COM CL A Call 225,300 -10.10 5,835 -0.24 n/a n/a n/a
2025-05-15 2025-03-31 13F ACM RESH COM CL A Call 250,600 47.85 5,849 128.57 n/a n/a n/a
2025-02-14 2024-12-31 13F ACM RESH COM CL A Call 169,500 1.92 2,559 -24.18 n/a n/a n/a
2024-11-14 2024-09-30 13F ACM RESH COM CL A Call 166,300 -29.74 3,376 -38.16 n/a n/a n/a
2024-08-14 2024-06-30 13F ACM RESH COM CL A Call 236,700 106.72 5,458 63.61 n/a n/a n/a
2024-05-15 2024-03-31 13F ACM RESH COM CL A Call 114,500 17.08 3,337 74.57 n/a n/a n/a
2024-02-14 2023-12-31 13F ACM RESH COM CL A Call 97,800 14.65 1,911 23.77 n/a n/a n/a
2023-11-14 2023-09-30 13F ACM RESH COM CL A Call 85,300 43.60 1,544 98.97 n/a n/a n/a
2023-08-14 2023-06-30 13F ACM RESH COM CL A Call 59,400 16.70 777 30.42 n/a n/a n/a
2023-05-15 2023-03-31 13F ACM RESH COM CL A Call 50,900 -16.83 596 26.33 n/a n/a n/a
2023-02-14 2022-12-31 13F ACM RESH COM CL A Call 61,200 32.18 472 -18.37 n/a n/a n/a
2022-11-14 2022-09-30 13F ACM RESH COM CL A Call 46,300 -7.77 577 -31.72 n/a n/a n/a
2022-08-15 2022-06-30 13F ACM RESH COM CL A Call 50,200 -58.24 845 -66.02 n/a n/a n/a
2022-05-16 2022-03-31 13F ACM RESH COM CL A Call 120,200 472.38 2,487 38.86 n/a n/a n/a
2022-02-14 2021-12-31 13F ACM RESH COM CL A Call 21,000 -70.42 1,791 -77.07 n/a n/a n/a
2021-11-15 2021-09-30 13F ACM RESH Cmn Call 71,000 -10.80 7,810 -4.02 n/a n/a n/a
2021-08-16 2021-06-30 13F ACM RESH COM CL A Call 79,600 80.50 8,137 128.37 n/a n/a n/a
2021-05-21 2021-03-31 13F/A ACM RESEARCH COM CL A Call 44,100 53.66 3,563 52.79 n/a n/a n/a
2021-05-17 2021-03-31 13F ACM RESEARCH COM CL A Call 44,100 3,563 n/a n/a n/a
2021-02-16 2020-12-31 13F ACM RESEARCH COM CL A Call 28,700 3.24 2,332 21.40 n/a n/a n/a
2020-11-16 2020-09-30 13F ACM RESEARCH COM CL A Call 27,800 79.35 1,921 98.66 n/a n/a n/a
2020-08-14 2020-06-30 13F ACM RESEARCH Cmn Call 15,500 43.52 967 202.19 n/a n/a n/a
2020-05-15 2020-03-31 13F ACM RESEARCH Cmn Call 10,800 320 n/a n/a n/a
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-15 2026-03-31 13F ACM RESH COM CL A Put 69,600 -63.12 2,739 -63.22 n/a n/a n/a
2026-02-17 2025-12-31 13F ACM RESH COM CL A Put 188,700 -55.51 7,444 -55.14 n/a n/a n/a
2025-11-14 2025-09-30 13F ACM RESH COM CL A Put 424,100 29.10 16,595 95.05 n/a n/a n/a
2025-08-14 2025-06-30 13F ACM RESH COM CL A Put 328,500 29.64 8,508 43.86 n/a n/a n/a
2025-05-15 2025-03-31 13F ACM RESH COM CL A Put 253,400 23.19 5,914 90.41 n/a n/a n/a
2025-02-14 2024-12-31 13F ACM RESH COM CL A Put 205,700 -18.60 3,106 -39.44 n/a n/a n/a
2024-11-14 2024-09-30 13F ACM RESH COM CL A Put 252,700 10.74 5,130 -2.53 n/a n/a n/a
2024-08-14 2024-06-30 13F ACM RESH COM CL A Put 228,200 93.39 5,262 53.05 n/a n/a n/a
2024-05-15 2024-03-31 13F ACM RESH COM CL A Put 118,000 28.54 3,439 91.75 n/a n/a n/a
2024-02-14 2023-12-31 13F ACM RESH COM CL A Put 91,800 40.80 1,794 51.95 n/a n/a n/a
2023-11-14 2023-09-30 13F ACM RESH COM CL A Put 65,200 74.80 1,180 142.30 n/a n/a n/a
2023-08-14 2023-06-30 13F ACM RESH COM CL A Put 37,300 -37.21 488 -29.83 n/a n/a n/a
2023-05-15 2023-03-31 13F ACM RESH COM CL A Put 59,400 55.91 695 136.86 n/a n/a n/a
2023-02-14 2022-12-31 13F ACM RESH COM CL A Put 38,100 58.09 294 -2.33 n/a n/a n/a
2022-11-14 2022-09-30 13F ACM RESH COM CL A Put 24,100 15.87 300 -14.29 n/a n/a n/a
2022-08-15 2022-06-30 13F ACM RESH COM CL A Put 20,800 -86.92 350 -89.36 n/a n/a n/a
2022-05-16 2022-03-31 13F ACM RESH COM CL A Put 159,000 616.22 3,290 73.80 n/a n/a n/a
2022-02-14 2021-12-31 13F ACM RESH COM CL A Put 22,200 -72.83 1,893 -78.94 n/a n/a n/a
2021-11-15 2021-09-30 13F ACM RESH Cmn Put 81,700 110.57 8,987 126.60 n/a n/a n/a
2021-08-16 2021-06-30 13F ACM RESH COM CL A Put 38,800 -49.08 3,966 -35.58 n/a n/a n/a
2021-05-21 2021-03-31 13F/A ACM RESEARCH COM CL A Put 76,200 228.45 6,156 226.58 n/a n/a n/a
2021-05-17 2021-03-31 13F ACM RESEARCH COM CL A Put 76,200 6,156 n/a n/a n/a
2021-02-16 2020-12-31 13F ACM RESEARCH COM CL A Put 23,200 -51.05 1,885 -42.44 n/a n/a n/a
2020-11-16 2020-09-30 13F ACM RESEARCH COM CL A Put 47,400 -3.07 3,275 7.41 n/a n/a n/a
2020-08-14 2020-06-30 13F ACM RESEARCH Cmn Put 48,900 146.97 3,049 420.31 n/a n/a n/a
2020-05-15 2020-03-31 13F ACM RESEARCH Cmn Put 19,800 586 n/a n/a n/a
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.