Monolithic Power Systems, Inc.
MX ˙ BMV ˙ US6098391054
SecurityMX:MPWR / Monolithic Power Systems, Inc.
InstitutionUs Bancorp \de\
Latest Disclosed Ownership12,202 shares
Latest Disclosed Value $ 13,341,581
Us Bancorp \de\ reports 1.30% increase in ownership of MPWR / Monolithic Power Systems, Inc.

On May 14, 2026 - Us Bancorp \de\ filed a 13F-HR form disclosing ownership of 12,202 shares of Monolithic Power Systems, Inc. (MX:MPWR) valued at $13,341,581 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 30, 2026 disclosing 12,045 shares of Monolithic Power Systems, Inc.. This represents a change in shares of 1.30% during the quarter.

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)
2026-05-14 2026-03-31 13F MONOLITHIC PWR SYS COM 609839105 12,202 157 1.30 13,342 22.20 0.0162
2026-01-30 2025-12-31 13F MONOLITHIC PWR SYS COM 609839105 12,045 293 2.49 10,917 0.90 0.0128
2025-11-12 2025-09-30 13F MONOLITHIC PWR SYS COM 609839105 11,752 -326 -2.70 10,820 22.48 0.0128
2025-07-24 2025-06-30 13F MONOLITHIC PWR SYS COM 609839105 12,078 -13 -0.11 8,834 25.98 0.0111
2025-05-08 2025-03-31 13F MONOLITHIC PWR SYS COM 609839105 12,091 -8,206 -40.43 7,013 -41.62 0.0094
2025-02-05 2024-12-31 13F MONOLITHIC PWR SYS COM 609839105 20,297 -1,110 -5.19 12,010 -39.32 0.0157
2024-10-28 2024-09-30 13F MONOLITHIC PWR SYS COM 609839105 21,407 -1,044 -4.65 19,791 7.29 0.0254
2024-08-07 2024-06-30 13F MONOLITHIC PWR SYS COM 609839105 22,451 273 1.23 18,448 22.78 0.0251
2024-05-08 2024-03-31 13F MONOLITHIC PWR SYS COM 609839105 22,178 -979 -4.23 15,024 2.85 0.0209
2024-02-09 2023-12-31 13F MONOLITHIC PWR SYS COM 609839105 23,157 8,153 54.34 14,607 110.72 0.0216
2023-11-03 2023-09-30 13F MONOLITHIC PWR SYS COM 609839105 15,004 -3,747 -19.98 6,932 -31.56 0.0113
2023-08-10 2023-06-30 13F MONOLITHIC PWR SYS COM 609839105 18,751 -231 -1.22 10,130 6.61 0.0163
2023-05-09 2023-03-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 18,982 -1,396 -6.85 9,501 31.87 0.0161
2023-02-13 2022-12-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 20,378 -1,077 -5.02 7,206 -7.59 0.0128
2022-10-27 2022-09-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 21,455 -1,114 -4.94 7,797 -10.05 0.0161
2022-08-01 2022-06-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 22,569 -530 -2.29 8,668 -22.74 0.0168
2022-05-11 2022-03-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 23,099 1,870 8.81 11,219 7.12 0.0187
2022-02-11 2021-12-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 21,229 299 1.43 10,473 3.23 0.0165
2021-11-10 2021-09-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 20,930 -768 -3.54 10,145 25.20 0.0191
2021-08-05 2021-06-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 21,698 -1,636 -7.01 8,103 -1.69 0.0152
2021-04-28 2021-03-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 23,334 -60 -0.26 8,242 -3.79 0.0167
2021-02-04 2020-12-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 23,394 -137 -0.58 8,567 30.20 0.0185
2020-11-10 2020-09-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 23,531 -1,111 -4.51 6,580 12.65 0.0160
2020-08-07 2020-06-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 24,642 -5,942 -19.43 5,841 14.04 0.0153
2020-05-13 2020-03-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 30,584 -363 -1.17 5,122 -7.02 0.0160
2020-02-04 2019-12-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 30,947 -3,970 -11.37 5,509 1.38 0.0141
2019-11-08 2019-09-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 34,917 243 0.70 5,434 15.45 0.0148
2019-08-13 2019-06-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 34,674 3,898 12.67 4,707 12.88 0.0131
2019-05-08 2019-03-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 30,776 -937 -2.95 4,170 13.10 0.0120
2019-02-13 2018-12-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 31,713 -1,762 -5.26 3,687 -12.26 0.0119
2018-10-31 2018-09-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 33,475 -887 -2.58 4,202 -8.51 0.0122
2018-08-08 2018-06-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 34,362 -8,571 -19.96 4,593 -7.60 0.0141
2018-05-08 2018-03-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 42,933 -957 -2.18 4,971 0.79 0.0153
2018-02-02 2017-12-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 43,890 592 1.37 4,932 6.92 0.0151
2017-11-13 2017-09-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 43,298 1,674 4.02 4,613 14.95 0.0148
2017-07-19 2017-06-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 41,624 886 2.17 4,013 6.96 0.0134
2017-05-03 2017-03-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 40,738 3,336 8.92 3,752 22.41 0.0129
2017-02-08 2016-12-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 37,402 30,482 440.49 3,065 450.27 0.0110
2016-11-04 2016-09-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 6,920 1,943 39.04 557 63.82 0.0021
2016-08-10 2016-06-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 4,977 2,376 91.35 340 104.82 0.0013
2016-05-13 2016-03-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 2,601 2,133 455.77 166 453.33 0.0007
2016-02-10 2015-12-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 468 29 6.61 30 36.36 0.0001
2015-11-16 2015-09-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 439 193 78.46 22 83.33 0.0001
2015-08-10 2015-06-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 246 84 51.85 12 33.33 0.0000
2015-05-08 2015-03-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 162 0 0.00 9 12.50 0.0000
2015-02-13 2014-12-31 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 162 0 0.00 8 14.29 0.0000
2014-11-14 2014-09-30 13F MONOLITHIC POWER SYSTEMS COMMON STOCK 609839105 162 162 7 0.0000
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.