Monolithic Power Systems, Inc.
MX ˙ BMV ˙ US6098391054
SecurityMX:MPWR / Monolithic Power Systems, Inc.
InstitutionNatixis
Latest Disclosed Ownership29,420 shares
Latest Disclosed Value $ 32,166,357
Natixis reports 3.42% decrease in ownership of MPWR / Monolithic Power Systems, Inc.

On May 14, 2026 - Natixis filed a 13F-HR form disclosing ownership of 29,420 shares of Monolithic Power Systems, Inc. (MX:MPWR) valued at $32,166,357 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 30,462 shares of Monolithic Power Systems, Inc.. This represents a change in shares of -3.42% 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)
2026-05-14 2026-03-31 13F MONOLITHIC PWR SYS COM 609839105 29,420 -1,042 -3.42 32,166 16.51 0.1150
2026-02-13 2025-12-31 13F MONOLITHIC PWR SYS COM 609839105 30,462 -7,231 -19.18 27,610 -20.44 0.0980
2025-11-14 2025-09-30 13F MONOLITHIC PWR SYS COM 609839105 37,693 5,154 15.84 34,702 45.81 0.1609
2025-08-13 2025-06-30 13F MONOLITHIC PWR SYS COM 609839105 32,539 881 2.78 23,798 33.47 0.1055
2025-07-18 2025-03-31 13F/A-1 MONOLITHIC PWR SYS COM 609839105 31,658 -28,817 -47.65 17,830 -50.17 0.0971
2025-05-14 2025-03-31 13F MONOLITHIC PWR SYS COM 609839105 31,658 -28,817 17,830 0.0978
2025-02-13 2024-12-31 13F MONOLITHIC PWR SYS COM 609839105 60,475 56,223 1,322.27 35,783 810.51 0.2186
2024-11-13 2024-09-30 13F MONOLITHIC PWR SYS COM 609839105 4,252 -621 -12.74 3,931 -1.85 0.0222
2024-08-13 2024-06-30 13F MONOLITHIC PWR SYS COM 609839105 4,873 -3,980 -44.96 4,004 -33.23 0.0229
2024-05-13 2024-03-31 13F MONOLITHIC PWR SYS COM 609839105 8,853 5,563 169.09 5,997 189.01 0.0312
2024-02-13 2023-12-31 13F MONOLITHIC PWR SYS COM 609839105 3,290 2,903 750.13 2,075 1,065.73 0.0151
2023-11-14 2023-09-30 13F MONOLITHIC PWR SYS COM 609839105 387 -6,708 -94.55 179 -95.35 0.0014
2023-08-11 2023-06-30 13F MONOLITHIC PWR SYS COM 609839105 7,095 5,646 389.65 3,833 428.55 0.0311
2023-05-12 2023-03-31 13F MONOLITHIC PWR SYS COM 609839105 1,449 -5,256 -78.39 725 -69.41 0.0065
2023-02-24 2022-12-31 13F/A-1 MONOLITHIC PWR SYS COM 609839105 6,705 2,883 75.43 2,371 69.53 0.0133
2023-02-13 2022-12-31 13F Monolithic Power Systems COM 609839105 5,722 1,900 2,020 0.0000
2022-11-14 2022-09-30 13F Monolithic Power Systems COM 609839105 3,822 -54 -1.39 1,398 -6.61 0.0065
2022-08-12 2022-06-30 13F Monolithic Power Systems COM 609839105 3,876 65 1.71 1,497 -19.12 0.0054
2022-05-13 2022-03-31 13F MONOLITHIC PWR SYS COM 609839105 3,811 -54,712 -93.49 1,851 -93.59 0.0064
2022-02-14 2021-12-31 13F MONOLITHIC PWR SYS COM 609839105 58,523 53,559 1,078.95 28,871 1,099.96 0.0985
2021-11-12 2021-09-30 13F MONOLITHIC PWR SYS COM 609839105 4,964 2,885 138.77 2,406 210.05 0.0083
2021-08-13 2021-06-30 13F MONOLITHIC PWR SYS COM 609839105 2,079 2,079 776 0.0034
2021-05-14 2021-03-31 13F MONOLITHIC PWR SYS COM 609839105 0 -13,834 -100.00 0 -100.00
2021-02-12 2020-12-31 13F MONOLITHIC PWR SYS COM 609839105 13,834 1,730 14.29 5,066 49.70 0.0184
2020-11-12 2020-09-30 13F MONOLITHIC PWR SYS COM 609839105 12,104 2,004 19.84 3,384 41.35 0.0249
2020-08-13 2020-06-30 13F MONOLITHIC PWR SYS COM 609839105 10,100 6,900 215.62 2,394 346.64 0.0186
2020-05-14 2020-03-31 13F MONOLITHIC PWR SYS COM 609839105 3,200 3,200 -68.32 536 -77.61 0.0042
2017-08-14 2017-06-30 13F MONOLITHIC PWR SYS COM 609839105 0 -3,084 -100.00 0 -100.00
2017-05-15 2017-03-31 13F MONOLITHIC PWR SYS COM 609839105 3,084 3,084 284 0.0035
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.