Monolithic Power Systems, Inc.
MX ˙ BMV ˙ US6098391054
SecurityMX:MPWR / Monolithic Power Systems, Inc.
InstitutionNatixis Advisors, L.p.
Latest Disclosed Ownership95,847 shares
Latest Disclosed Value $ 104,794
Natixis Advisors, L.p. reports 25.21% decrease in ownership of MPWR / Monolithic Power Systems, Inc.

On May 13, 2026 - Natixis Advisors, L.p. filed a 13F-HR form disclosing ownership of 95,847 shares of Monolithic Power Systems, Inc. (MX:MPWR) valued at $104,794 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 10, 2026 disclosing 128,155 shares of Monolithic Power Systems, Inc.. This represents a change in shares of -25.21% 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)
2026-05-13 2026-03-31 13F MONOLITHIC PWR SYS COM 609839105 95,847 -32,308 -25.21 105 -10.34 0.1458
2026-02-10 2025-12-31 13F MONOLITHIC PWR SYS COM 609839105 128,155 -3,104 -2.36 116 -3.33 0.1646
2025-11-13 2025-09-30 13F MONOLITHIC PWR SYS INC COM 609839105 131,259 -1,330 -1.00 121 25.00 0.1763
2025-08-13 2025-06-30 13F MONOLITHIC PWR SYS COM 609839105 132,589 351 0.27 97 26.32 0.1539
2025-05-08 2025-03-31 13F MONOLITHIC PWR SYS COM 609839105 132,238 -17,445 -11.65 77 -13.64 0.1417
2025-02-10 2024-12-31 13F MONOLITHIC PWR SYS COM 609839105 149,683 -16,625 -10.00 89 -42.48 0.1655
2024-11-06 2024-09-30 13F MONOLITHIC PWR SYS COM 609839105 166,308 -4,318 -2.53 154 9.29 0.2998
2024-08-01 2024-06-30 13F MONOLITHIC PWR SYS COM 609839105 170,626 -734 -0.43 140 20.69 0.3048
2024-04-25 2024-03-31 13F MONOLITHIC PWR SYS COM 609839105 171,360 15,582 10.00 116 18.37 0.2669
2024-02-06 2023-12-31 13F MONOLITHIC PWR SYS COM 609839105 155,778 30,261 24.11 98 71.93 0.2587
2023-11-13 2023-09-30 13F MONOLITHIC PWR SYS COM 609839105 125,517 43,954 53.89 58 29.55 0.1773
2023-08-15 2023-06-30 13F MONOLITHIC PWR SYS COM 609839105 81,563 8,927 12.29 44 22.22 0.1361
2023-05-11 2023-03-31 13F MONOLITHIC PWR SYS COM 609839105 72,636 9,335 14.75 36 63.64 0.1251
2023-01-27 2022-12-31 13F MONOLITHIC PWR SYS COM 609839105 63,301 -16,861 -21.03 22 -99.92 0.0846
2022-11-14 2022-09-30 13F MONOLITHIC PWR SYSTEMS COM 609839105 80,162 17,942 28.84 29,131 21.91 0.1232
2022-08-12 2022-06-30 13F MONOLITHIC PWR SYS COM 609839105 62,220 -1,056 -1.67 23,895 -22.25 0.1051
2022-05-12 2022-03-31 13F MONOLITHIC PWR SYS COM 609839105 63,276 -20,875 -24.81 30,732 -25.97 0.1172
2022-02-08 2021-12-31 13F MONOLITHIC PWR SYS COM 609839105 84,151 -6,044 -6.70 41,515 -5.03 0.1585
2021-11-15 2021-09-30 13F MONOLITHIC PWR SYS COM 609839105 90,195 78,160 649.44 43,716 872.76 0.1798
2021-08-12 2021-06-30 13F MONOLITHIC PWR SYS COM 609839105 12,035 -503 -4.01 4,494 1.49 0.0210
2021-05-05 2021-03-31 13F MONOLITHIC PWR SYS COM 609839105 12,538 -1,511 -10.76 4,428 -13.94 0.0231
2021-02-12 2020-12-31 13F MONOLITHIC PWR SYS COM 609839105 14,049 -6,689 -32.25 5,145 -11.28 0.0296
2020-11-12 2020-09-30 13F MONOLITHIC PWR SYS COM 609839105 20,738 -3,794 -15.47 5,799 -0.26 0.0365
2020-08-11 2020-06-30 13F MONOLITHIC PWR SYS COM 609839105 24,532 -450 -1.80 5,814 38.99 0.0386
2020-04-27 2020-03-31 13F MONOLITHIC PWR SYS COM 609839105 24,982 -420 -1.65 4,183 -7.50 0.0341
2020-02-10 2019-12-31 13F MONOLITHIC PWR SYS COM 609839105 25,402 3,341 15.14 4,522 31.72 0.0319
2019-11-12 2019-09-30 13F MONOLITHIC PWR SYS COM 609839105 22,061 6,409 40.95 3,433 61.55 0.0272
2019-08-12 2019-06-30 13F MONOLITHIC PWR SYS COM 609839105 15,652 3,716 31.13 2,125 31.42 0.0174
2019-05-15 2019-03-31 13F/A-1 MONOLITHIC PWR SYS COM 609839105 11,936 588 5.18 1,617 22.59 0.0142
2019-05-15 2019-03-31 13F MONOLITHIC PWR SYS COM 609839105 11,936 588 1,617
2019-02-13 2018-12-31 13F/A-1 MONOLITHIC PWR SYS COM 609839105 11,348 431 3.95 1,319 -3.72 0.0130
2019-02-13 2018-12-31 13F MONOLITHIC PWR SYS COM 609839105 11,348 431 1,319
2018-11-13 2018-09-30 13F MONOLITHIC PWR SYS COM 609839105 10,917 136 1.26 1,370 -4.93 0.0121
2018-08-14 2018-06-30 13F/A-1 MONOLITHIC PWR SYS COM 609839105 10,781 -941 -8.03 1,441 6.19 0.0138
2018-08-14 2018-06-30 13F MONOLITHIC PWR SYS COM 609839105 10,781 1,441
2018-05-10 2018-03-31 13F MONOLITHIC PWR SYS COM 609839105 11,722 577 5.18 1,357 8.39 0.0134
2018-02-14 2017-12-31 13F MONOLITHIC PWR SYS COM 609839105 11,145 -2 -0.02 1,252 5.48 0.0128
2017-11-14 2017-09-30 13F MONOLITHIC PWR SYS COM 609839105 11,147 68 0.61 1,187 11.14 0.0125
2017-07-27 2017-06-30 13F MONOLITHIC PWR SYS COM 609839105 11,079 -142 -1.27 1,068 3.39 0.0116
2017-05-12 2017-03-31 13F MONOLITHIC PWR SYS COM 609839105 11,221 -573 -4.86 1,033 6.94 0.0114
2017-02-07 2016-12-31 13F MONOLITHIC PWR SYS COM 609839105 11,794 459 4.05 966 5.92 0.0116
2016-11-04 2016-09-30 13F MONOLITHIC PWR SYS COM 609839105 11,335 11,335 912 0.0118
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.