Monolithic Power Systems, Inc.
MX ˙ BMV ˙ US6098391054
SecurityMX:MPWR / Monolithic Power Systems, Inc.
InstitutionMillennium Management Llc
ManagerIsrael Englander
Latest Disclosed Ownership0 shares
Latest Disclosed Value $ 0
Millennium Management Llc ownership in MPWR / Monolithic Power Systems, Inc.

On May 15, 2026 - Millennium Management Llc filed a 13F-HR form disclosing ownership of 0 shares of Monolithic Power Systems, Inc. (MX:MPWR) valued at $0 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 24,679 shares of Monolithic Power Systems, Inc.. This represents a change in shares of -100.00% during the quarter.

Millennium Management Llc has a history of taking positions in derivatives of the underlying security (MPWR) in the form of stock options. The firm currently holds call options representing 2,000 of underlying shares valued at $2,186,700 USD and put options representing 10,900 of underlying shares valued at $11,917,515 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.

MX:MPWR / Monolithic Power Systems, 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 MONOLITHIC PWR SYS COM 609839105 0 -24,679 -100.00 0 -100.00
2026-02-17 2025-12-31 13F MONOLITHIC PWR SYS COM 609839105 24,679 -145,811 -85.52 22,368 -85.75 0.0094
2025-11-14 2025-09-30 13F MONOLITHIC PWR SYS COM 609839105 170,490 154,958 997.67 156,960 1,281.80 0.0670
2025-08-14 2025-06-30 13F MONOLITHIC PWR SYS COM 609839105 15,532 -132,971 -89.54 11,360 -86.81 0.0055
2025-05-15 2025-03-31 13F MONOLITHIC PWR SYS COM 609839105 148,503 23,937 19.22 86,129 16.86 0.0458
2025-02-14 2024-12-31 13F MONOLITHIC PWR SYS COM 609839105 124,566 -34,362 -21.62 73,706 -49.84 0.0360
2024-11-14 2024-09-30 13F MONOLITHIC PWR SYS COM 609839105 158,928 152,467 2,359.80 146,929 2,668.05 0.0697
2024-08-14 2024-06-30 13F MONOLITHIC PWR SYS COM 609839105 6,461 -153,147 -95.95 5,309 -95.09 0.0025
2024-05-15 2024-03-31 13F MONOLITHIC PWR SYS COM 609839105 159,608 156,398 4,872.21 108,122 5,241.95 0.0462
2024-02-14 2023-12-31 13F MONOLITHIC PWR SYS COM 609839105 3,210 938 41.29 2,025 92.95 0.0009
2023-11-14 2023-09-30 13F MONOLITHIC PWR SYS COM 609839105 2,272 -21,204 -90.32 1,050 -91.73 0.0005
2023-08-14 2023-06-30 13F MONOLITHIC PWR SYS COM 609839105 23,476 -174,504 -88.14 12,682 -87.20 0.0063
2023-05-15 2023-03-31 13F MONOLITHIC PWR SYS COM 609839105 197,980 -250,979 -55.90 99,097 -37.58 0.0568
2023-02-14 2022-12-31 13F MONOLITHIC PWR SYS COM 609839105 448,959 36,448 8.84 158,756 5.90 0.0878
2022-11-14 2022-09-30 13F MONOLITHIC PWR SYS COM 609839105 412,511 269,205 187.85 149,906 172.38 0.0886
2022-08-15 2022-06-30 13F MONOLITHIC PWR SYS COM 609839105 143,306 67,370 88.72 55,035 49.22 0.0341
2022-05-16 2022-03-31 13F MONOLITHIC PWR SYS COM 609839105 75,936 15,473 25.59 36,881 23.65 0.0196
2022-02-14 2021-12-31 13F MONOLITHIC PWR SYS COM 609839105 60,463 14,712 32.16 29,828 34.51 0.0152
2021-11-15 2021-09-30 13F MONOLITHIC PWR SYS COM 609839105 45,751 24,500 115.29 22,175 179.42 0.0133
2021-08-16 2021-06-30 13F MONOLITHIC PWR SYS COM 609839105 21,251 -135,440 -86.44 7,936 -85.66 0.0049
2021-05-17 2021-03-31 13F MONOLITHIC PWR SYS COM 609839105 156,691 75,134 92.12 55,345 85.29 0.0396
2021-02-16 2020-12-31 13F MONOLITHIC PWR SYS COM 609839105 81,557 -67,541 -45.30 29,869 -28.35 0.0216
2020-11-16 2020-09-30 13F MONOLITHIC PWR SYS COM 609839105 149,098 113,112 314.32 41,689 388.79 0.0513
2020-08-14 2020-06-30 13F MONOLITHIC PWR SYS COM 609839105 35,986 -10,141 -21.98 8,529 10.42 0.0117
2020-05-14 2020-03-31 13F MONOLITHIC PWR SYS COM 609839105 46,127 -13,827 -23.06 7,724 -27.63 0.0174
2020-02-14 2019-12-31 13F MONOLITHIC PWR SYS COM 609839105 59,954 2,912 5.11 10,673 20.23 0.0134
2019-11-14 2019-09-30 13F MONOLITHIC PWR SYS COM 609839105 57,042 -59,021 -50.85 8,877 -43.67 0.0140
2019-08-15 2019-06-30 13F/A-1 MONOLITHIC PWR SYS COM 609839105 116,063 -22,328 -16.13 15,759 -15.96 0.0237
2019-08-14 2019-06-30 13F FISERV COM 609839105 797,929 659,538 72,739
2019-05-14 2019-03-31 13F MONOLITHIC PWR SYS COM 609839105 138,391 53,242 62.53 18,751 89.42 0.0281
2019-02-15 2018-12-31 13F/A-1 MONOLITHIC PWR SYS COM 609839105 85,149 361 0.43 9,899 -6.99 0.0154
2019-02-14 2018-12-31 13F MONOLITHIC PWR SYS COM 609839105 85,149 9,899
2018-11-14 2018-09-30 13F MONOLITHIC PWR SYS COM 609839105 84,788 -214,017 -71.62 10,643 -73.35 0.0130
2018-08-14 2018-06-30 13F MONOLITHIC PWR SYS COM 609839105 298,805 298,805 39,941 0.0521
2018-05-15 2018-03-31 13F MONOLITHIC PWR SYS COM 609839105 0 -52,831 -100.00 0 -100.00
2018-02-14 2017-12-31 13F MONOLITHIC PWR SYS COM 609839105 52,831 52,831 5,936 0.0082
2017-08-14 2017-06-30 13F MONOLITHIC PWR SYS COM 609839105 0 -7,790 -100.00 0 -100.00
2017-05-15 2017-03-31 13F MONOLITHIC PWR SYS COM 609839105 7,790 7,790 717 0.0013
2015-11-16 2015-09-30 13F MONOLITHIC PWR SYS COM 609839105 0 -23,745 -100.00 0 -100.00
2015-08-14 2015-06-30 13F MONOLITHIC PWR SYS COM 609839105 23,745 -26,354 -52.60 1,204 -54.36 0.0023
2015-05-15 2015-03-31 13F MONOLITHIC PWR SYS COM 609839105 50,099 50,099 2,638 0.0049
2014-08-14 2014-06-30 13F MONOLITHIC PWR SYS COM 609839105 0 -15,889 -100.00 0 -100.00
2014-05-15 2014-03-31 13F MONOLITHIC PWR SYS COM 609839105 15,889 4,534 39.93 616 56.35 0.0018
2014-02-14 2013-12-31 13F MONOLITHIC PWR SYS COM 609839105 11,355 -19,545 -63.25 394 -57.91 0.0012
2013-11-14 2013-09-30 13F MONOLITHIC PWR SYS COM 609839105 30,900 9,447 44.04 936 81.04 0.0030
2013-08-14 2013-06-30 13F MONOLITHIC PWR SYS COM 609839105 21,453 21,453 517 0.0016
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 MONOLITHIC PWR SYS COM Call 2,000 -60.00 2,187 -51.75 n/a n/a n/a
2026-02-17 2025-12-31 13F MONOLITHIC PWR SYS COM Call 5,000 -48.98 4,532 -49.78 n/a n/a n/a
2025-11-14 2025-09-30 13F MONOLITHIC PWR SYS COM Call 9,800 -44.00 9,022 -29.51 n/a n/a n/a
2025-08-14 2025-06-30 13F MONOLITHIC PWR SYS COM Call 17,500 -0.57 12,799 25.39 n/a n/a n/a
2025-05-15 2025-03-31 13F MONOLITHIC PWR SYS COM Call 17,600 30.37 10,208 27.80 n/a n/a n/a
2025-02-14 2024-12-31 13F MONOLITHIC PWR SYS COM Call 13,500 -35.10 7,988 -58.46 n/a n/a n/a
2024-11-14 2024-09-30 13F MONOLITHIC PWR SYS COM Call 20,800 101.94 19,230 127.21 n/a n/a n/a
2024-08-14 2024-06-30 13F MONOLITHIC PWR SYS COM Call 10,300 60.94 8,463 95.22 n/a n/a n/a
2024-05-15 2024-03-31 13F MONOLITHIC PWR SYS COM Call 6,400 -64.64 4,335 -62.03 n/a n/a n/a
2024-02-14 2023-12-31 13F MONOLITHIC PWR SYS COM Call 18,100 376.32 11,417 550.54 n/a n/a n/a
2023-11-14 2023-09-30 13F MONOLITHIC PWR SYS COM Call 3,800 375.00 1,756 306.25 n/a n/a n/a
2023-08-14 2023-06-30 13F MONOLITHIC PWR SYS COM Call 800 432 n/a n/a n/a
2021-08-16 2021-06-30 13F MONOLITHIC PWR SYS COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2021-05-17 2021-03-31 13F MONOLITHIC PWR SYS COM Call 3,200 1,130 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 MONOLITHIC PWR SYS COM Put 10,900 7.92 11,918 30.18 n/a n/a n/a
2026-02-17 2025-12-31 13F MONOLITHIC PWR SYS COM Put 10,100 6.32 9,154 4.66 n/a n/a n/a
2025-11-14 2025-09-30 13F MONOLITHIC PWR SYS COM Put 9,500 -6.86 8,746 17.24 n/a n/a n/a
2025-08-14 2025-06-30 13F MONOLITHIC PWR SYS COM Put 10,200 -26.62 7,460 -7.46 n/a n/a n/a
2025-05-15 2025-03-31 13F MONOLITHIC PWR SYS COM Put 13,900 47.87 8,062 44.96 n/a n/a n/a
2025-02-14 2024-12-31 13F MONOLITHIC PWR SYS COM Put 9,400 -59.66 5,562 -74.18 n/a n/a n/a
2024-11-14 2024-09-30 13F MONOLITHIC PWR SYS COM Put 23,300 375.51 21,541 435.02 n/a n/a n/a
2024-08-14 2024-06-30 13F MONOLITHIC PWR SYS COM Put 4,900 -36.36 4,026 -22.81 n/a n/a n/a
2024-05-15 2024-03-31 13F MONOLITHIC PWR SYS COM Put 7,700 -75.40 5,216 -73.58 n/a n/a n/a
2024-02-14 2023-12-31 13F MONOLITHIC PWR SYS COM Put 31,300 580.43 19,743 829.08 n/a n/a n/a
2023-11-14 2023-09-30 13F MONOLITHIC PWR SYS COM Put 4,600 -22.03 2,125 -33.32 n/a n/a n/a
2023-08-14 2023-06-30 13F MONOLITHIC PWR SYS COM Put 5,900 3,187 n/a n/a n/a
2022-02-14 2021-12-31 13F MONOLITHIC PWR SYS COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2021-11-15 2021-09-30 13F MONOLITHIC PWR SYS COM Put 4,500 -4.26 2,181 24.27 n/a n/a n/a
2021-08-16 2021-06-30 13F MONOLITHIC PWR SYS COM Put 4,700 46.88 1,755 55.31 n/a n/a n/a
2021-05-17 2021-03-31 13F MONOLITHIC PWR SYS COM Put 3,200 1,130 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.