Monolithic Power Systems, Inc.
MX ˙ BMV ˙ US6098391054
SecurityMX:MPWR / Monolithic Power Systems, Inc.
InstitutionStifel Financial Corp
Latest Disclosed Ownership79,334 shares
Latest Disclosed Value $ 86,754,110
Stifel Financial Corp reports 1.71% decrease in ownership of MPWR / Monolithic Power Systems, Inc.

On May 12, 2026 - Stifel Financial Corp filed a 13F-HR form disclosing ownership of 79,334 shares of Monolithic Power Systems, Inc. (MX:MPWR) valued at $86,754,110 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 80,712 shares of Monolithic Power Systems, Inc.. This represents a change in shares of -1.71% 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)
2026-05-12 2026-03-31 13F MONOLITHIC PWR SYS COM 609839105 79,334 -1,378 -1.71 86,754 18.57 0.0187
2026-02-13 2025-12-31 13F MONOLITHIC PWR SYS COM 609839105 80,712 -18,610 -18.74 73,167 -19.99 0.0658
2025-11-12 2025-09-30 13F MONOLITHIC PWR SYS COM 609839105 99,322 -6,011 -5.71 91,452 18.69 0.0835
2025-08-14 2025-06-30 13F MONOLITHIC PWR SYS COM 609839105 105,333 22,066 26.50 77,048 59.53 0.0749
2025-05-14 2025-03-31 13F MONOLITHIC PWR SYS COM 609839105 83,267 6,278 8.15 48,298 6.02 0.0513
2025-02-13 2024-12-31 13F MONOLITHIC PWR SYS COM 609839105 76,989 46,484 152.38 45,556 61.52 0.0475
2024-11-14 2024-09-30 13F MONOLITHIC PWR SYS COM 609839105 30,505 1,817 6.33 28,204 19.65 0.0296
2024-08-13 2024-06-30 13F MONOLITHIC PWR SYS COM 609839105 28,688 31 0.11 23,573 21.42 0.0265
2024-05-14 2024-03-31 13F MONOLITHIC PWR SYS COM 609839105 28,657 10,901 61.39 19,414 73.34 0.0221
2024-02-12 2023-12-31 13F MONOLITHIC PWR SYS COM 609839105 17,756 24 0.14 11,201 36.72 0.0141
2023-11-13 2023-09-30 13F MONOLITHIC PWR SYS COM 609839105 17,732 -1,542 -8.00 8,192 -21.32 0.0115
2023-08-14 2023-06-30 13F MONOLITHIC PWR SYS COM 609839105 19,274 -32,976 -63.11 10,412 -60.19 0.0142
2023-05-12 2023-03-31 13F MONOLITHIC PWR SYS COM 609839105 52,250 -22,239 -29.86 26,153 -0.71 0.0375
2023-02-13 2022-12-31 13F MONOLITHIC PWR SYS COM 609839105 74,489 8,630 13.10 26,340 10.06 0.0395
2022-11-14 2022-09-30 13F MONOLITHIC PWR SYS COM 609839105 65,859 45,281 220.05 23,933 202.83 0.0392
2022-08-15 2022-06-30 13F MONOLITHIC PWR SYS COM 609839105 20,578 3,808 22.71 7,903 -2.97 0.0124
2022-05-13 2022-03-31 13F MONOLITHIC PWR SYS COM 609839105 16,770 -513 -2.97 8,145 -4.46 0.0111
2022-02-14 2021-12-31 13F MONOLITHIC PWR SYS COM 609839105 17,283 -817 -4.51 8,525 -2.82 0.0113
2021-11-15 2021-09-30 13F MONOLITHIC PWR SYS COM 609839105 18,100 602 3.44 8,772 34.25 0.0129
2021-08-13 2021-06-30 13F MONOLITHIC PWR SYS COM 609839105 17,498 1,320 8.16 6,534 14.35 0.0098
2021-05-14 2021-03-31 13F MONOLITHIC PWR SYS COM 609839105 16,178 -2,315 -12.52 5,714 -15.64 0.0094
2021-02-12 2020-12-31 13F MONOLITHIC PWR SYS COM 609839105 18,493 1,279 7.43 6,773 40.72 0.0121
2020-11-16 2020-09-30 13F MONOLITHIC PWR SYS COM 609839105 17,214 4,759 38.21 4,813 63.10 0.0099
2020-08-14 2020-06-30 13F MONOLITHIC PWR SYS COM 609839105 12,455 1,928 18.31 2,951 60.64 0.0068
2020-05-14 2020-03-31 13F MONOLITHIC PWR SYS COM 609839105 10,527 -85,969 -89.09 1,837 -89.31 0.0051
2020-02-13 2019-12-31 13F MONOLITHIC PWR SYS COM 609839105 96,496 -7,489 -7.20 17,190 6.05 0.0358
2019-11-19 2019-09-30 13F/A-1 MONOLITHIC PWR SYS COM 609839105 103,985 -38,370 -26.95 16,210 -16.17 0.0414
2019-11-13 2019-09-30 13F MONOLITHIC PWR SYS COM 609839105 103,985 -38,370 16,210 9,086.5175
2019-08-14 2019-06-30 13F MONOLITHIC PWR SYS COM 609839105 142,355 -2,261 -1.56 19,336 -1.35 0.0499
2019-05-14 2019-03-31 13F MONOLITHIC PWR SYS COM 609839105 144,616 -3,448 -2.33 19,601 13.59 0.0554
2019-02-13 2018-12-31 13F MONOLITHIC PWR SYS COM 609839105 148,064 13,293 9.86 17,256 1.84 0.0558
2018-11-13 2018-09-30 13F MONOLITHIC PWR SYS COM 609839105 134,771 -57,163 -29.78 16,944 -33.94 0.0485
2018-08-14 2018-06-30 13F MONOLITHIC PWR SYS COM 609839105 191,934 4,504 2.40 25,649 18.15 0.0787
2018-05-11 2018-03-31 13F MONOLITHIC PWR SYS COM 609839105 187,430 -19,594 -9.46 21,708 -6.60 0.0685
2018-02-14 2017-12-31 13F MONOLITHIC PWR SYS COM 609839105 207,024 12,176 6.25 23,242 11.96 0.0737
2017-11-13 2017-09-30 13F MONOLITHIC PWR SYS COM 609839105 194,848 1,938 1.00 20,759 11.60 0.0720
2017-08-14 2017-06-30 13F MONOLITHIC PWR SYS COM 609839105 192,910 26,602 16.00 18,601 21.42 0.0691
2017-05-10 2017-03-31 13F MONOLITHIC PWR SYS COM 609839105 166,308 23,317 16.31 15,319 30.84 0.0593
2017-02-16 2016-12-31 13F MONOLITHIC PWR SYS COM 609839105 142,991 26,050 22.28 11,708 24.46 0.0497
2016-11-15 2016-09-30 13F MONOLITHIC PWR SYS COM 609839105 116,941 20,785 21.62 9,407 43.20 0.0423
2016-08-17 2016-06-30 13F MONOLITHIC PWR SYS COM 609839105 96,156 6,429 7.17 6,569 15.06 0.0304
2016-05-16 2016-03-31 13F MONOLITHIC PWR SYS COM 609839105 89,727 4,410 5.17 5,709 5.08 0.0304
2016-03-21 2015-12-31 13F/A-2 MONOLITHIC PWR SYS COM 609839105 85,317 10,198 13.58 5,433 41.30 0.0283
2016-02-26 2015-12-31 13F/A-1 MONOLITHIC PWR SYS COM 609839105 165,482 80,165 5,081 0.0266
2016-02-16 2015-12-31 13F MONOLITHIC PWR SYS COM 609839105 165,482 5,342
2015-11-16 2015-09-30 13F MONOLITHIC PWR SYS COM 609839105 75,119 26,724 55.22 3,845 56.81 0.0216
2015-08-17 2015-06-30 13F/A-1 MONOLITHIC PWR SYS COM 609839105 48,395 4,854 11.15 2,452 7.03 0.0127
2015-08-17 2015-06-30 13F MONOLITHIC PWR SYS COM 609839105 48,356 2,451
2015-05-14 2015-03-31 13F MONOLITHIC PWR SYS COM 609839105 43,541 -103 -0.24 2,291 5.53 0.0125
2015-02-13 2014-12-31 13F MONOLITHIC PWR SYS COM 609839105 43,644 5,754 15.19 2,171 30.08 0.0121
2014-11-13 2014-09-30 13F MONOLITHIC PWR SYS COM 609839105 37,890 -6,901 -15.41 1,669 -12.02 0.0147
2014-08-14 2014-06-30 13F MONOLITHIC PWR SYS COM 609839105 44,791 3,064 7.34 1,897 17.24 0.0170
2014-05-15 2014-03-31 13F MONOLITHIC PWR SYS COM 609839105 41,727 41,727 1,618 0.0155
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.