Monolithic Power Systems, Inc.
US ˙ NasdaqGS ˙ US6098391054

SecurityMPWR / Monolithic Power Systems, Inc.
InstitutionFifth Third Bancorp
Latest Disclosed Ownership25,811 shares
Latest Disclosed Value $ 28,220,136
Fifth Third Bancorp reports 53.42% increase in ownership of MPWR / Monolithic Power Systems, Inc.

On May 1, 2026 - Fifth Third Bancorp filed a 13F-HR form disclosing ownership of 25,811 shares of Monolithic Power Systems, Inc. (US:MPWR) valued at $28,220,457 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 2, 2026 disclosing 16,824 shares of Monolithic Power Systems, Inc.. This represents a change in shares of 53.42% during the quarter. The current value of the position is $43,617,751 USD.

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)
2026-05-01 2026-03-31 13F MONOLITHIC PWR SYS COM 609839105 25,811 8,987 53.42 28,220 85.07 0.0516
2026-02-02 2025-12-31 13F MONOLITHIC PWR SYS COM 609839105 16,824 1,889 12.65 15,249 10.90 0.0484
2025-11-07 2025-09-30 13F MONOLITHIC PWR SYS COM 609839105 14,935 2,314 18.33 13,750 48.96 0.0440
2025-07-15 2025-06-30 13F MONOLITHIC PWR SYS COM 609839105 12,621 3,216 34.19 9,231 69.23 0.0319
2025-04-15 2025-03-31 13F MONOLITHIC PWR SYS COM 609839105 9,405 2,171 30.01 5,455 27.43 0.0207
2025-01-21 2024-12-31 13F MONOLITHIC PWR SYS COM 609839105 7,234 -1,887 -20.69 4,280 -49.24 0.0155
2024-10-17 2024-09-30 13F MONOLITHIC PWR SYS COM 609839105 9,121 -75 -0.82 8,432 11.59 0.0305
2024-07-22 2024-06-30 13F MONOLITHIC PWR SYS COM 609839105 9,196 -1,694 -15.56 7,556 2.43 0.0288
2024-04-23 2024-03-31 13F MONOLITHIC PWR SYS COM 609839105 10,890 -29 -0.27 7,377 7.11 0.0289
2024-01-19 2023-12-31 13F MONOLITHIC PWR SYS COM 609839105 10,919 416 3.96 6,887 41.94 0.0293
2023-10-31 2023-09-30 13F MONOLITHIC PWR SYS COM 609839105 10,503 -159 -1.49 4,852 -15.75 0.0225
2023-07-26 2023-06-30 13F MONOLITHIC PWR SYS COM 609839105 10,662 -153 -1.41 5,760 6.39 0.0254
2023-04-24 2023-03-31 13F MONOLITHIC PWR SYS COM 609839105 10,815 409 3.93 5,413 47.13 0.0252
2023-01-25 2022-12-31 13F MONOLITHIC PWR SYS COM 609839105 10,406 -487 -4.47 3,680 -7.07 0.0177
2022-10-25 2022-09-30 13F MONOLITHIC PWR SYS COM 609839105 10,893 2,898 36.25 3,959 28.96 0.0207
2022-08-04 2022-06-30 13F MONOLITHIC PWR SYS COM 609839105 7,995 847 11.85 3,070 -11.58 0.0148
2022-04-19 2022-03-31 13F MONOLITHIC PWR SYS COM 609839105 7,148 1,105 18.29 3,472 16.47 0.0142
2022-02-01 2021-12-31 13F MONOLITHIC PWR SYS COM 609839105 6,043 505 9.12 2,981 11.07 0.0116
2021-10-15 2021-09-30 13F MONOLITHIC PWR SYS COM 609839105 5,538 214 4.02 2,684 35.01 0.0117
2021-08-06 2021-06-30 13F MONOLITHIC PWR SYS COM 609839105 5,324 416 8.48 1,988 14.65 0.0087
2021-05-07 2021-03-31 13F MONOLITHIC PWR SYS COM 609839105 4,908 599 13.90 1,734 9.89 0.0080
2021-02-16 2020-12-31 13F MONOLITHIC PWR SYS COM 609839105 4,309 448 11.60 1,578 46.11 0.0078
2020-11-09 2020-09-30 13F MONOLITHIC PWR SYS COM 609839105 3,861 272 7.58 1,080 26.91 0.0060
2020-08-05 2020-06-30 13F MONOLITHIC PWR SYS COM 609839105 3,589 777 27.63 851 80.68 0.0051
2020-05-05 2020-03-31 13F MONOLITHIC PWR SYS COM 609839105 2,812 1,002 55.36 471 46.27 0.0034
2020-02-14 2019-12-31 13F MONOLITHIC PWR SYS COM 609839105 1,810 528 41.19 322 61.00 0.0018
2019-11-14 2019-09-30 13F MONOLITHIC PWR SYS COM 609839105 1,282 374 41.19 200 62.60 0.0012
2019-08-07 2019-06-30 13F MONOLITHIC PWR SYS COM 609839105 908 425 87.99 123 89.23 0.0008
2019-05-14 2019-03-31 13F MONOLITHIC PWR SYS COM 609839105 483 135 38.79 65 62.50 0.0004
2019-02-14 2018-12-31 13F MONOLITHIC PWR SYS COM 609839105 348 108 45.00 40 33.33 0.0003
2018-11-14 2018-09-30 13F MONOLITHIC PWR SYS COM 609839105 240 -9 -3.61 30 -9.09 0.0002
2018-08-14 2018-06-30 13F MONOLITHIC PWR SYS COM 609839105 249 18 7.79 33 22.22 0.0002
2018-05-15 2018-03-31 13F MONOLITHIC PWR SYS COM 609839105 231 79 51.97 27 58.82 0.0002
2018-02-14 2017-12-31 13F MONOLITHIC PWR SYS COM 609839105 152 31 25.62 17 30.77 0.0001
2017-11-14 2017-09-30 13F MONOLITHIC PWR SYS COM 609839105 121 121 13 0.0001
2016-05-13 2016-03-31 13F MONOLITHIC PWR SYS COM 609839105 0 -102 -100.00 0 -100.00
2016-02-16 2015-12-31 13F MONOLITHIC PWR SYS COM 609839105 102 2 2.00 6 20.00 0.0001
2015-11-13 2015-09-30 13F MONOLITHIC PWR SYS COM 609839105 100 34 51.52 5 66.67 0.0000
2015-08-14 2015-06-30 13F MONOLITHIC PWR SYS COM 609839105 66 2 3.12 3 0.00 0.0000
2015-05-14 2015-03-31 13F MONOLITHIC PWR SYS COM 609839105 64 64 3 0.0000
2014-08-14 2014-06-30 13F MONOLITHIC PWR SYS COM 609839105 0 -844 -100.00 0 -100.00
2014-05-15 2014-03-31 13F MONOLITHIC PWR SYS COM 609839105 844 -430 -33.75 33 -25.00 0.0003
2014-02-14 2013-12-31 13F MONOLITHIC PWR SYS COM 609839105 1,274 -75 -5.56 44 7.32 0.0004
2013-11-14 2013-09-30 13F MONOLITHIC PWR SYS COM 609839105 1,349 1,349 41 0.0004
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.