Monolithic Power Systems, Inc.
US ˙ NasdaqGS ˙ US6098391054

SecurityMPWR / Monolithic Power Systems, Inc.
InstitutionPitcairn Co
Latest Disclosed Ownership0 shares
Latest Disclosed Value $ 0
Pitcairn Co closes position in MPWR / Monolithic Power Systems, Inc.

On February 12, 2026 - Pitcairn Co filed a 13F-HR form disclosing ownership of 0 shares of Monolithic Power Systems, Inc. (US:MPWR) valued at $0 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 12, 2025 disclosing 670 shares of Monolithic Power Systems, Inc.. The current value of the position is $0 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.

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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)
2026-02-12 2025-12-31 13F MONOLITHIC PWR SYS COM 609839105 0 -100.00 0
2025-11-12 2025-09-30 13F MONOLITHIC PWR SYS COM 609839105 670 -636 -48.70 617 -35.50 0.0487
2025-08-19 2025-06-30 13F/A-1 MONOLITHIC PWR SYS COM 609839105 1,306 -528 -28.79 955 -10.16 0.0626
2025-08-14 2025-06-30 13F MONOLITHIC PWR SYS COM 609839105 6,424 4,590 1,644 0.0964
2025-05-09 2025-03-31 13F MONOLITHIC PWR SYS COM 609839105 1,834 -364 -16.56 1,064 -18.23 0.0641
2025-02-12 2024-12-31 13F MONOLITHIC PWR SYS COM 609839105 2,198 -188 -7.88 1,301 -41.04 0.0768
2024-11-12 2024-09-30 13F MONOLITHIC PWR SYS COM 609839105 2,386 -26 -1.08 2,206 11.31 0.1304
2024-08-13 2024-06-30 13F MONOLITHIC PWR SYS COM 609839105 2,412 18 0.75 1,982 22.21 0.1210
2024-05-13 2024-03-31 13F MONOLITHIC PWR SYS COM 609839105 2,394 247 11.50 1,622 19.72 0.1051
2024-02-14 2023-12-31 13F MONOLITHIC PWR SYS COM 609839105 2,147 320 17.52 1,354 60.43 0.1038
2023-11-13 2023-09-30 13F MONOLITHIC PWR SYS COM 609839105 1,827 699 61.97 844 38.59 0.0720
2023-08-11 2023-06-30 13F MONOLITHIC PWR SYS INC COM COM 609839105 1,128 -18 -1.57 609 6.28 0.0528
2023-05-05 2023-03-31 13F MONOLITHIC PWR SYS INC COM COM 609839105 1,146 13 1.15 574 43.25 0.0527
2023-02-13 2022-12-31 13F MONOLITHIC PWR SYS INC COM COM 609839105 1,133 -362 -24.21 401 -26.34 0.0400
2022-11-14 2022-09-30 13F MONOLITHIC PWR SYS INC COM COM 609839105 1,495 309 26.05 543 19.34 0.0588
2022-08-12 2022-06-30 13F MONOLITHIC PWR SYS INC COM COM 609839105 1,186 48 4.22 455 -17.72 0.0481
2022-05-12 2022-03-31 13F MONOLITHIC PWR SYS INC COM COM 609839105 1,138 -414 -26.68 553 -27.81 0.0482
2022-02-14 2021-12-31 13F MONOLITHIC PWR SYS INC COM COM 609839105 1,552 -274 -15.01 766 -13.45 0.0493
2021-11-10 2021-09-30 13F MONOLITHIC PWR SYS INC COM COM 609839105 1,826 1,826 885 0.0611
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.