Monolithic Power Systems, Inc.
MX ˙ BMV ˙ US6098391054
SecurityMX:MPWR / Monolithic Power Systems, Inc.
InstitutionHighTower Advisors, LLC
Latest Disclosed Ownership3,772 shares
Latest Disclosed Value $ 4,124,984
HighTower Advisors, LLC reports 14.16% decrease in ownership of MPWR / Monolithic Power Systems, Inc.

On May 5, 2026 - HighTower Advisors, LLC filed a 13F-HR form disclosing ownership of 3,772 shares of Monolithic Power Systems, Inc. (MX:MPWR) valued at $4,124,984 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 6, 2026 disclosing 4,394 shares of Monolithic Power Systems, Inc.. This represents a change in shares of -14.16% 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)
2026-05-05 2026-03-31 13F MONOLITHIC PWR SYS COM 609839105 3,772 -622 -14.16 4,125 3.57 0.0044
2026-02-06 2025-12-31 13F MONOLITHIC PWR SYS COM 609839105 4,394 616 16.30 3,982 14.49 0.0044
2025-11-07 2025-09-30 13F MONOLITHIC PWR SYS COM 609839105 3,778 -597 -13.65 3,479 8.72 0.0039
2025-08-11 2025-06-30 13F MONOLITHIC PWR SYS COM 609839105 4,375 239 5.78 3,200 33.40 0.0040
2025-05-13 2025-03-31 13F MONOLITHIC PWR SYS COM 609839105 4,136 -2,070 -33.35 2,399 -34.68 0.0033
2025-02-07 2024-12-31 13F MONOLITHIC PWR SYS COM 609839105 6,206 -314 -4.82 3,672 -39.72 0.0050
2024-11-14 2024-09-30 13F MONOLITHIC PWR SYS COM 609839105 6,520 -2,559 -28.19 6,090 -18.33 0.0087
2024-08-13 2024-06-30 13F MONOLITHIC PWR SYS COM 609839105 9,079 -203 -2.19 7,457 18.80 0.0115
2024-05-06 2024-03-31 13F MONOLITHIC PWR SYS COM 609839105 9,282 -800 -7.93 6,277 -1.49 0.0102
2024-02-12 2023-12-31 13F MONOLITHIC PWR SYS COM 609839105 10,082 1,542 18.06 6,372 62.43 0.0107
2023-11-08 2023-09-30 13F MONOLITHIC PWR SYS COM 609839105 8,540 -1,413 -14.20 3,923 -27.39 0.0074
2023-08-14 2023-06-30 13F MONOLITHIC PWR SYS COM 609839105 9,953 -1,867 -15.80 5,403 -10.20 0.0106
2023-05-12 2023-03-31 13F MONOLITHIC PWR SYS COM 609839105 11,820 1,420 13.65 6,017 63.82 0.0131
2023-02-09 2022-12-31 13F MONOLITHIC PWR SYS COM 609839105 10,400 5,595 116.44 3,673 110.85 0.0084
2022-11-09 2022-09-30 13F MONOLITHIC PWR SYS COM 609839105 4,805 226 4.94 1,742 -1.30 0.0047
2022-08-10 2022-06-30 13F MONOLITHIC PWR SYS COM 609839105 4,579 113 2.53 1,765 -17.91 0.0046
2022-05-12 2022-03-31 13F MONOLITHIC PWR SYS COM 609839105 4,466 -2,250 -33.50 2,150 -34.35 0.0048
2022-02-10 2021-12-31 13F MONOLITHIC PWR SYS COM 609839105 6,716 -51 -0.75 3,275 0.18 0.0072
2021-11-12 2021-09-30 13F MONOLITHIC PWR SYS COM 609839105 6,767 1,963 40.86 3,269 82.83 0.0087
2021-08-06 2021-06-30 13F MONOLITHIC PWR SYS COM 609839105 4,804 82 1.74 1,788 7.65 0.0052
2021-05-10 2021-03-31 13F MONOLITHIC PWR SYS COM 609839105 4,722 -97 -2.01 1,661 -5.62 0.0052
2021-02-10 2020-12-31 13F MONOLITHIC PWR SYS COM 609839105 4,819 -1,190 -19.80 1,760 4.51 0.0073
2020-11-13 2020-09-30 13F MONOLITHIC PWR SYS COM 609839105 6,009 -137 -2.23 1,684 15.58 0.0081
2020-08-10 2020-06-30 13F MONOLITHIC PWR SYS COM 609839105 6,146 -721 -10.50 1,457 25.82 0.0079
2020-05-21 2020-03-31 13F MONOLITHIC PWR SYS COM 609839105 6,867 -344 -4.77 1,158 -9.67 0.0075
2020-02-14 2019-12-31 13F MONOLITHIC PWR SYS COM 609839105 7,211 300 4.34 1,282 19.14 0.0076
2019-11-12 2019-09-30 13F MONOLITHIC PWR SYS COM 609839105 6,911 -444 -6.04 1,076 8.25 0.0059
2019-08-13 2019-06-30 13F MONOLITHIC PWR SYS COM 609839105 7,355 -11 -0.15 994 0.20 0.0059
2019-05-15 2019-03-31 13F MONOLITHIC PWR SYS COM 609839105 7,366 -92 -1.23 992 14.95 0.0066
2019-02-14 2018-12-31 13F MONOLITHIC PWR SYS COM 609839105 7,458 119 1.62 863 -7.40 0.0066
2018-11-09 2018-09-30 13F MONOLITHIC PWR SYS COM 609839105 7,339 362 5.19 932 0.65 0.0067
2018-08-14 2018-06-30 13F MONOLITHIC PWR SYS COM 609839105 6,977 -14 -0.20 926 13.90 0.0073
2018-05-15 2018-03-31 13F MONOLITHIC PWR SYS COM 609839105 6,991 337 5.06 813 9.86 0.0068
2018-02-14 2017-12-31 13F MONOLITHIC PWR SYS COM 609839105 6,654 -1,296 -16.30 740 -12.22 0.0061
2017-11-14 2017-09-30 13F MONOLITHIC PWR SYS COM 609839105 7,950 1,606 25.32 843 39.57 0.0072
2017-09-22 2017-06-30 13F/A-1 MONOLITHIC PWR SYS COM 609839105 6,344 -371 -5.52 604 -2.11 0.0054
2017-08-14 2017-06-30 13F MONOLITHIC PWR SYS COM 609839105 6,344 -371 604
2017-05-15 2017-03-31 13F MONOLITHIC PWR SYS COM 609839105 6,715 6,715 617 0.0059
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.