Monolithic Power Systems, Inc.
US ˙ NasdaqGS ˙ US6098391054

SecurityMPWR / Monolithic Power Systems, Inc.
InstitutionStrs Ohio
Latest Disclosed Ownership69,807 shares
Latest Disclosed Value $ 76,323,483
Strs Ohio reports 10.28% decrease in ownership of MPWR / Monolithic Power Systems, Inc.

On April 24, 2026 - Strs Ohio filed a 13F-HR form disclosing ownership of 69,807 shares of Monolithic Power Systems, Inc. (US:MPWR) valued at $76,323,483 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 2, 2026 disclosing 77,809 shares of Monolithic Power Systems, Inc.. This represents a change in shares of -10.28% during the quarter. The current value of the position is $117,966,151 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)
2026-04-24 2026-03-31 13F MONOLITHIC POWER SYSTEMS COM_STK 609839105 69,807 -8,002 -10.28 76,323 8.23 0.3028
2026-02-02 2025-12-31 13F MONOLITHIC POWER SYSTEMS COM_STK 609839105 77,809 2 0.00 70,523 -1.55 0.2630
2025-10-30 2025-09-30 13F MONOLITHIC POWER SYSTEMS COM_STK 609839105 77,807 -31,599 -28.88 71,632 -10.48 0.2626
2025-08-04 2025-06-30 13F MONOLITHIC POWER SYSTEMS COM_STK 609839105 109,406 -4,594 -4.03 80,017 21.02 0.2987
2025-05-28 2025-03-31 13F MONOLITHIC POWER SYSTEMS COM_STK 609839105 114,000 0 0.00 66,118 -1.98 0.2769
2025-05-28 2024-12-31 13F MONOLITHIC POWER SYSTEMS COM_STK 609839105 114,000 10,854 10.52 67,454 -29.26 0.2676
2024-11-01 2024-09-30 13F MONOLITHIC POWER SYSTEMS COM_STK 609839105 103,146 -5,126 -4.73 95,358 7.19 0.3669
2024-08-05 2024-06-30 13F MONOLITHIC POWER SYSTEMS COM_STK 609839105 108,272 3,268 3.11 88,965 125,201.41 0.3515
2024-05-13 2024-03-31 13F MONOLITHIC POWER SYSTEMS COM_STK 609839105 105,004 -15,092 -12.57 71 -5.33 0.2834
2024-01-30 2023-12-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 120,096 -7,116 -5.59 76 29.31 0.3153
2023-10-26 2023-09-30 13F/A-1 MONOLITHIC POWER SYSTEMS COM 609839105 127,212 1,212 0.96 59 -14.71 0.2616
2023-10-26 2023-09-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 127,212 1,212 59 0.2616
2023-07-31 2023-06-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 126,000 -7,569 -5.67 68 3.03 0.2873
2023-08-02 2023-03-31 13F/A-2 MONOLITHIC POWER SYSTEMS COM 609839105 133,569 -35,222 -20.87 67 11.86 0.2896
2023-08-02 2023-03-31 13F/A-1 MONOLITHIC POWER SYSTEMS COM 609839105 133,569 -35,222 67 0.2896
2023-04-27 2023-03-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 133,569 -35,222 67 0.3450
2023-01-26 2022-12-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 168,791 427 0.25 60 -99.90 0.2695
2022-10-27 2022-09-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 168,364 164 0.10 61,183 -5.28 0.2915
2022-07-25 2022-06-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 168,200 -11,152 -6.22 64,595 -25.84 0.2909
2022-04-21 2022-03-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 179,352 19,068 11.90 87,107 10.16 0.3186
2022-01-24 2021-12-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 160,284 13,806 9.43 79,072 11.38 0.2745
2021-10-22 2021-09-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 146,478 0 0.00 70,994 29.78 0.2671
2021-07-26 2021-06-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 146,478 -162 -0.11 54,702 5.61 0.1967
2021-04-23 2021-03-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 146,640 21,345 17.04 51,794 12.88 0.1950
2021-01-25 2020-12-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 125,295 -20,305 -13.95 45,886 12.71 0.1770
2020-12-14 2020-09-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 145,600 -30,239 -17.20 40,711 -2.31 0.1705
2020-07-23 2020-06-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 175,839 2,876 1.66 41,673 43.88 0.1821
2020-04-23 2020-03-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 172,963 39,718 29.81 28,964 22.11 0.1525
2020-01-24 2019-12-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 133,245 68,245 104.99 23,720 134.50 0.0994
2019-10-21 2019-09-30 13F/A-1 MONOLITHIC POWER SYSTEMS COM 609839105 65,000 65,000 10,115 0.0443
2019-10-21 2019-09-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 65,000 -68,245 10,115 44,769.5510
2019-07-25 2019-06-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 0 -2,147 -100.00 0 -100.00
2019-04-19 2019-03-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 2,147 -258 -10.73 290 3.94 0.0013
2019-01-23 2018-12-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 2,405 -310 -11.42 279 -17.94 0.0014
2018-10-19 2018-09-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 2,715 199 7.91 340 1.19 0.0015
2018-08-06 2018-06-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 2,516 -3,784 -60.06 336 -53.91 0.0014
2018-04-20 2018-03-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 6,300 300 5.00 729 8.16 0.0032
2018-01-23 2017-12-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 6,000 0 0.00 674 5.48 0.0029
2017-10-23 2017-09-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 6,000 200 3.45 639 14.31 0.0027
2017-07-26 2017-06-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 5,800 400 7.41 559 12.47 0.0025
2017-04-26 2017-03-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 5,400 500 10.20 497 23.94 0.0022
2017-01-24 2016-12-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 4,900 -400 -7.55 401 -5.87 0.0018
2016-10-27 2016-09-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 5,300 400 8.16 426 27.54 0.0019
2016-07-26 2016-06-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 4,900 600 13.95 334 22.34 0.0015
2016-04-25 2016-03-31 13F/A-1 MONOLITHIC POWER SYSTEMS COM 609839105 4,300 0 0.00 273 0.00 0.0012
2016-01-28 2015-12-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 4,300 2,200 104.76 273 155.14 0.0012
2015-10-21 2015-09-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 2,100 -2,100 -50.00 107 -49.53 0.0005
2015-08-04 2015-06-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 4,200 300 7.69 212 3.41 0.0009
2015-04-27 2015-03-31 13F/A-1 MONOLITHIC POWER SYSTEMS COM 609839105 3,900 -21,600 -84.71 205 -83.83 0.0009
2015-04-21 2015-03-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 3,900 205
2015-01-23 2014-12-31 13F MONOLITHIC POWER SYSTEMS COM 609839105 25,500 -300 -1.16 1,268 11.62 0.0055
2014-10-29 2014-09-30 13F/A-1 MONOLITHIC POWER SYSTEMS COM 609839105 25,800 25,800 1,136 0.0050
2014-10-20 2014-09-30 13F MONOLITHIC POWER SYSTEMS COM 609839105 25,800 1,136
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.