Monolithic Power Systems, Inc.
MX ˙ BMV ˙ US6098391054
SecurityMX:MPWR / Monolithic Power Systems, Inc.
InstitutionMather Group, Llc.
Latest Disclosed Ownership992 shares
Latest Disclosed Value $ 1,084,603
Mather Group, Llc. reports 4.86% increase in ownership of MPWR / Monolithic Power Systems, Inc.

On April 13, 2026 - Mather Group, Llc. filed a 13F-HR form disclosing ownership of 992 shares of Monolithic Power Systems, Inc. (MX:MPWR) valued at $1,084,603 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 13, 2026 disclosing 946 shares of Monolithic Power Systems, Inc.. This represents a change in shares of 4.86% 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)
2026-04-13 2026-03-31 13F MONOLITHIC PWR SYS COM 609839105 992 46 4.86 1,085 26.49 0.0108
2026-01-13 2025-12-31 13F MONOLITHIC PWR SYS COM 609839105 946 42 4.65 858 3.00 0.0088
2025-10-21 2025-09-30 13F MONOLITHIC PWR SYS COM 609839105 904 147 19.42 832 50.45 0.0084
2025-07-15 2025-06-30 13F MONOLITHIC PWR SYS COM 609839105 757 348 85.09 554 133.33 0.0059
2025-04-25 2025-03-31 13F MONOLITHIC PWR SYS COM 609839105 409 229 127.22 237 123.58 0.0027
2025-01-27 2024-12-31 13F MONOLITHIC PWR SYS COM 609839105 180 -133 -42.49 107 -63.32 0.0014
2024-10-07 2024-09-30 13F MONOLITHIC PWR SYS COM 609839105 313 151 93.21 289 165.14 0.0037
2024-07-09 2024-06-30 13F MONOLITHIC PWR SYS COM 609839105 162 38 30.65 110 39.74 0.0014
2024-04-09 2024-03-31 13F MONOLITHIC PWR SYS COM 609839105 124 124 78 0.0012
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.