Monolithic Power Systems, Inc.
US ˙ NasdaqGS ˙ US6098391054

SecurityMPWR / Monolithic Power Systems, Inc.
InstitutionFmr Llc
Latest Disclosed Ownership3,977,007 shares
Ownership 8.30%
Fmr Llc ownership in MPWR / Monolithic Power Systems, Inc.

2026-02-05 - Fmr Llc has filed an SCHEDULE 13G/A form with the Securities and Exchange Commission (SEC) disclosing ownership of 3,977,007 shares of Monolithic Power Systems, Inc. (US:MPWR). This represents 8.3 percent ownership of the company. In their previous filing dated 2024-11-12 , Fmr Llc had reported owning 3,519,372 shares, indicating an increase of 13.00 percent.

Institutional Ownership: 13D/G Filings

This table shows a history of the 13D/G filings made by the investor and/or investor group. Note that the share values in this table are not directly comparable to any numbers shown in the 13F table (if any).

File
Date		Effective
Date		Form Prev
Shares		 Latest
Shares		 ΔShares
(Percent)		 Ownership
(Percent)		 ΔOwnership
(Percent)
2026-02-05 2026-02-05 13G/A 3,519,372 3,977,007 13.00 8.30 14.99
2024-11-12 2024-11-12 13G/A 2,528,118 3,519,372 39.21 7.22 36.81
2024-02-09 2024-02-09 13G 1,432,703 2,528,118 76.46 5.28 56.19
2019-02-13 2019-02-13 13G/A 2,096,055 1,432,703 -31.65 3.38 -33.08
2018-02-13 2018-02-13 13G/A 3,416,014 2,096,055 -38.64 5.05 -39.89
2017-02-14 2017-02-14 13G/A 4,139,254 3,416,014 -17.47 8.40 -19.82
2016-02-12 2016-02-12 13G/A 4,139,254 10.47
2015-02-13 2015-02-13 13G/A 3,881,591 10.02
2014-02-14 2014-02-14 13G/A 4,140,291 10.84
2013-02-14 2013-02-14 13G/A 5,320,137 15.00
2012-09-10 2012-09-10 13G 5,293,116 15.00

Important Note: One of the primary uses of the 13D/G filings is to evaluate the ability of a firm to control a company (ie, the "beneficial ownership"). To that end, firms are required to report not just direct holdings in companies, but indirect holdings that they control. For investment firms, these indirect holdings can include shares in funds they manage, advisory accounts, and in the case of activist campaigns, pledged votes. Therefore, share counts listed in 13D/G filings can differ significantly than share counts listed in 13F filings.

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 MONOLITHIC PWR SYS COM 609839105 4,400,831 423,823 10.66 4,811,648 33.49 0.0504
2026-02-17 2025-12-31 13F MONOLITHIC PWR SYS COM 609839105 3,977,008 412,212 11.56 3,604,601 9.83 0.1838
2025-11-13 2025-09-30 13F MONOLITHIC PWR SYS COM 609839105 3,564,796 172,092 5.07 3,281,895 32.26 0.1706
2025-08-14 2025-06-30 13F MONOLITHIC PWR SYS COM 609839105 3,392,704 -106,005 -3.03 2,481,356 22.28 0.1399
2025-05-12 2025-03-31 13F MONOLITHIC PWR SYS COM 609839105 3,498,709 380,562 12.20 2,029,182 9.98 0.1296
2025-02-13 2024-12-31 13F MONOLITHIC PWR SYS COM 609839105 3,118,147 -401,229 -11.40 1,845,008 -43.29 0.1101
2024-11-13 2024-09-30 13F MONOLITHIC PWR SYS COM 609839105 3,519,376 361,416 11.44 3,253,664 25.39 0.1980
2024-08-13 2024-06-30 13F MONOLITHIC PWR SYS COM 609839105 3,157,960 348,590 12.41 2,594,833 36.35 0.1661
2024-05-13 2024-03-31 13F MONOLITHIC PWR SYS COM 609839105 2,809,370 281,245 11.12 1,903,124 19.34 0.1278
2024-02-13 2023-12-31 13F MONOLITHIC PWR SYS COM 609839105 2,528,125 -1,055,678 -29.46 1,594,691 -3.69 0.1225
2023-11-13 2023-09-30 13F MONOLITHIC PWR SYS COM 609839105 3,583,803 929,009 34.99 1,655,717 15.45 0.1431
2023-08-11 2023-06-30 13F MONOLITHIC PWR SYS COM 609839105 2,654,794 897,645 51.09 1,434,199 63.07 0.1202
2023-08-11 2023-03-31 13F/A-1 MONOLITHIC PWR SYS COM 609839105 1,757,149 293,326 20.04 879,524 69.92 0.0805
2023-05-11 2023-03-31 13F MONOLITHIC PWR SYS COM 609839105 1,757,149 293,326 879,524 0.0160
2023-02-13 2022-12-31 13F MONOLITHIC PWR SYS COM 609839105 1,463,823 192,825 15.17 517,623 12.07 0.0514
2022-11-10 2022-09-30 13F MONOLITHIC PWR SYS COM 609839105 1,270,998 475,119 59.70 461,882 51.12 0.0482
2022-08-12 2022-06-30 13F MONOLITHIC PWR SYS COM 609839105 795,879 443,857 126.09 305,648 78.77 0.0305
2022-05-13 2022-03-31 13F MONOLITHIC PWR SYS COM 609839105 352,022 5,102 1.47 170,969 -0.10 0.0137
2022-02-14 2021-12-31 13F MONOLITHIC PWR SYS COM 609839105 346,920 50,188 16.91 171,146 19.00 0.0126
2022-02-14 2021-09-30 13F/A-1 MONOLITHIC PWR SYS COM 609839105 296,732 63,515 27.23 143,820 65.13 0.0114
2021-11-15 2021-09-30 13F MONOLITHIC PWR SYS COM 609839105 296,732 63,515 143,820 0.0114
2021-08-13 2021-06-30 13F MONOLITHIC PWR SYS COM 609839105 233,217 -135,453 -36.74 87,094 -33.12 0.0068
2021-05-14 2021-03-31 13F MONOLITHIC PWR SYS COM 609839105 368,670 196,862 114.58 130,217 106.95 0.0111
2021-02-08 2020-12-31 13F MONOLITHIC PWR SYS COM 609839105 171,808 -7,836 -4.36 62,921 25.27 0.0056
2020-11-13 2020-09-30 13F MONOLITHIC PWR SYS COM 609839105 179,644 -110,748 -38.14 50,230 -27.02 0.0051
2020-08-24 2020-06-30 13F/A-1 MONOLITHIC PWR SYS COM 609839105 290,392 84,718 41.19 68,823 99.82 0.0076
2020-08-13 2020-06-30 13F MONOLITHIC PWR SYS COM 609839105 290,392 84,718 68,823 1,690.7797
2020-05-14 2020-03-31 13F MONOLITHIC PWR SYS COM 609839105 205,674 37,512 22.31 34,442 15.05 0.0048
2020-02-07 2019-12-31 13F MONOLITHIC PWR SYS COM 609839105 168,162 -391,469 -69.95 29,936 -65.63 0.0033
2019-11-13 2019-09-30 13F MONOLITHIC PWR SYS COM 609839105 559,631 -55,061 -8.96 87,096 4.35 0.0104
2019-08-13 2019-06-30 13F MONOLITHIC PWR SYS COM 609839105 614,692 -225,962 -26.88 83,463 -26.72 0.0097
2019-05-13 2019-03-31 13F MONOLITHIC PWR SYS COM 609839105 840,654 -592,050 -41.32 113,899 -31.61 0.0136
2019-02-13 2018-12-31 13F MONOLITHIC PWR SYS COM 609839105 1,432,704 44,356 3.19 166,552 -4.43 0.0228
2018-11-09 2018-09-30 13F MONOLITHIC PWR SYS COM 609839105 1,388,348 -276,280 -16.60 174,279 -21.68 0.0196
2018-08-10 2018-06-30 13F MONOLITHIC PWR SYS COM 609839105 1,664,628 -68,418 -3.95 222,511 10.90 0.0263
2018-05-14 2018-03-31 13F MONOLITHIC PWR SYS COM 609839105 1,733,046 -361,638 -17.26 200,635 -14.75 0.0238
2018-02-12 2017-12-31 13F MONOLITHIC PWR SYS COM 609839105 2,094,684 -162,390 -7.19 235,359 -2.13 0.0276
2017-11-13 2017-09-30 13F MONOLITHIC PWR SYS COM 609839105 2,257,074 -900,983 -28.53 240,491 -21.00 0.0291
2017-08-29 2017-06-30 13F/A-1 MONOLITHIC PWR SYS COM 609839105 3,158,057 -140,640 -4.26 304,437 0.21 0.0378
2017-08-11 2017-06-30 13F MONOLITHIC PWR SYS COM 609839105 3,158,057 -140,640 304,437
2017-05-11 2017-03-31 13F MONOLITHIC PWR SYS COM 609839105 3,298,697 -117,297 -3.43 303,811 8.55 0.0386
2017-02-10 2016-12-31 13F MONOLITHIC PWR SYS COM 609839105 3,415,994 -238,198 -6.52 279,873 -4.86 0.0374
2016-11-14 2016-09-30 13F MONOLITHIC PWR SYS COM 609839105 3,654,192 -86,121 -2.30 294,162 15.11 0.0392
2016-08-11 2016-06-30 13F MONOLITHIC PWR SYS COM 609839105 3,740,313 -137,679 -3.55 255,539 3.54 0.0349
2016-05-16 2016-03-31 13F MONOLITHIC PWR SYS COM 609839105 3,877,992 -261,224 -6.31 246,795 -6.41 0.0341
2016-02-12 2015-12-31 13F MONOLITHIC PWR SYS COM 609839105 4,139,216 -325,647 -7.29 263,710 15.36 0.0355
2015-11-10 2015-09-30 13F MONOLITHIC PWR SYS COM 609839105 4,464,863 -204,918 -4.39 228,601 -3.46 0.0325
2015-08-25 2015-06-30 13F/A-1 MONOLITHIC PWR SYS COM 609839105 4,669,781 155,504 3.44 236,804 -0.37 0.0303
2015-08-13 2015-06-30 13F MONOLITHIC PWR SYS COM 609839105 4,669,781 236,804
2015-05-14 2015-03-31 13F MONOLITHIC PWR SYS COM 609839105 4,514,277 632,686 16.30 237,677 23.10 0.0303
2015-02-17 2014-12-31 13F MONOLITHIC PWR SYS COM 609839105 3,881,591 -187,575 -4.61 193,070 7.71 0.0251
2014-11-14 2014-09-30 13F MONOLITHIC PWR SYS COM 609839105 4,069,166 -176,060 -4.15 179,246 -0.30 0.0243
2014-08-14 2014-06-30 13F MONOLITHIC PWR SYS COM 609839105 4,245,226 233,995 5.83 179,785 15.61 0.0241
2014-05-15 2014-03-31 13F MONOLITHIC PWR SYS COM 609839105 4,011,231 -129,060 -3.12 155,516 8.37 0.0216
2014-02-13 2013-12-31 13F MONOLITHIC PWR SYS COM 609839105 4,140,291 -7,479 -0.18 143,502 14.26 0.0203
2013-11-14 2013-09-30 13F MONOLITHIC PWR SYS COM 609839105 4,147,770 449,180 12.14 125,594 40.84 0.0192
2013-09-24 2013-06-30 13F/A-1 MONOLITHIC PWR SYS COM 609839105 3,698,590 3,698,590 89,173 0.0146
2013-08-14 2013-06-30 13F MONOLITHIC PWR SYS COM 609839105 3,698,590 89,173 0.0146
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.