Monolithic Power Systems, Inc.
US ˙ NasdaqGS ˙ US6098391054

SecurityMPWR / Monolithic Power Systems, Inc.
InstitutionLeelyn Smith, LLC
Latest Disclosed Ownership3,345 shares
Latest Disclosed Value $ 3,657,274
Leelyn Smith, LLC reports 2.16% decrease in ownership of MPWR / Monolithic Power Systems, Inc.

On April 27, 2026 - Leelyn Smith, LLC filed a 13F-HR form disclosing ownership of 3,345 shares of Monolithic Power Systems, Inc. (US:MPWR) valued at $3,657,256 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 28, 2026 disclosing 3,419 shares of Monolithic Power Systems, Inc.. This represents a change in shares of -2.16% during the quarter. The current value of the position is $5,652,682 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.

Upgrade to unlock premium data and export to Excel .

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)
2026-04-27 2026-03-31 13F MONOLITHIC PWR SYS COM 609839105 3,345 -74 -2.16 3,657 18.04 0.5129
2026-01-28 2025-12-31 13F MONOLITHIC PWR SYS COM 609839105 3,419 6 0.18 3,099 -1.37 0.4481
2025-10-30 2025-09-30 13F MONOLITHIC PWR SYS COM 609839105 3,413 89 2.68 3,142 29.26 0.4732
2025-07-31 2025-06-30 13F MONOLITHIC PWR SYS COM 609839105 3,324 193 6.16 2,431 33.81 0.3988
2025-05-02 2025-03-31 13F MONOLITHIC PWR SYS COM 609839105 3,131 165 5.56 1,816 3.48 0.3227
2025-02-10 2024-12-31 13F MONOLITHIC PWR SYS COM 609839105 2,966 304 11.42 1,755 -28.69 0.3126
2024-11-12 2024-09-30 13F MONOLITHIC PWR SYS COM 609839105 2,662 -1 -0.04 2,461 12.48 0.4442
2024-08-08 2024-06-30 13F MONOLITHIC PWR SYS COM 609839105 2,663 143 5.67 2,188 28.25 0.4229
2024-05-14 2024-03-31 13F MONOLITHIC PWR SYS COM 609839105 2,520 -8 -0.32 1,707 7.03 0.3417
2024-02-09 2023-12-31 13F MONOLITHIC PWR SYS COM 609839105 2,528 101 4.16 1,594 42.19 0.3492
2023-11-06 2023-09-30 13F MONOLITHIC PWR SYS COM 609839105 2,427 -5 -0.21 1,121 -14.62 0.2737
2023-08-10 2023-06-30 13F MONOLITHIC PWR SYS COM 609839105 2,432 -33 -1.34 1,314 6.49 0.3174
2023-05-12 2023-03-31 13F MONOLITHIC PWR SYS COM 609839105 2,465 52 2.15 1,234 44.55 0.3158
2023-02-10 2022-12-31 13F MONOLITHIC POWER COMMON STOCK 609839105 2,413 799 49.50 853 45.56 0.2343
2022-11-14 2022-09-30 13F MONOLITHIC POWER COMMON STOCK 609839105 1,614 -566 -25.96 586 -29.99 0.2024
2022-08-09 2022-06-30 13F MONOLITHIC POWER COMMON STOCK 609839105 2,180 -46 -2.07 837 -22.57 0.2170
2022-05-11 2022-03-31 13F MONOLITHIC POWER COMMON STOCK 609839105 2,226 105 4.95 1,081 3.25 0.2817
2022-02-14 2021-12-31 13F MONOLITHIC POWER COMMON STOCK 609839105 2,121 153 7.77 1,047 9.75 0.2800
2021-11-12 2021-09-30 13F MONOLITHIC POWER COMMON STOCK 609839105 1,968 238 13.76 954 47.68 0.2762
2021-08-31 2021-06-30 13F MONOLITHIC POWER COMMON STOCK 609839105 1,730 1,730 646 0.1902
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.