Company / CIK 0001280452
MONOLITHIC POWER SYSTEMS INC
- Ticker
- MPWR
- Size, estimated from filings
- Large cap ($10B – $200B)
- Insiders on file
- 12
- Members of Congress who traded it
- 4
- Federal contracts on record
- none matched
- Lobbying filings on record
- none matched
- SEC filings
- EDGAR ↗
- Latest trade on record
- September 28, 2026
MONOLITHIC POWER SYSTEMS INC (MPWR) has 12 insiders on file who disclosed 351 transactions in the last 12 months (0 open-market buys, 319 sales, about $1.10B at reported prices), and 7 congressional trades in its stock are on record. No federal contract award that started in the last 180 days was found for a recipient with exactly this name; no lobbying filing names it as client this year.
MONOLITHIC POWER SYSTEMS INC in charts
Who is trading this stock
Which people account for the buying and selling over the last 12 months?
BoughtSold
8 people account for the disclosed buying and selling in MONOLITHIC POWER SYSTEMS INC over the last 12 months; the most active is Hsing Michael with $488M.
Insiders
| Name | Role | Rows | Bought | Sold | Last filed |
|---|---|---|---|---|---|
| Hsing Michael | CEO | 93 | 0 | 90 | September 30, 2026 |
| Tseng Saria | EVP & General Counsel | 74 | 0 | 67 | September 2, 2026 |
| DEAN ROBERT W II | Interim CFO | 8 | 0 | 5 | August 26, 2026 |
| CHANG KUO WEI HERBERT | Director | 5 | 0 | 4 | August 25, 2026 |
| Sciammas Maurice | EVP, WW Sales & Marketing | 71 | 0 | 62 | August 6, 2026 |
| Zhou Jeff | Director | 5 | 0 | 4 | May 27, 2026 |
| Xiao Deming | EVP, Global Operations | 8 | 0 | 6 | May 8, 2026 |
| Elmiger Eugen J | Director | 10 | 0 | 9 | May 8, 2026 |
| Wynne Eileen | Director | 2 | 0 | 1 | May 8, 2026 |
| Lee Victor K | Director | 9 | 0 | 8 | February 11, 2026 |
| BLEGEN THEODORE | EVP and CFO | 81 | 0 | 79 | February 10, 2026 |
| Martinez Carintia | Director | 1 | 0 | 0 | February 5, 2026 |
Rows are this company's Form 4 rows for each person. "Bought" and "sold" count open-market purchases (code P) and sales only. More in insider buying and insider selling.
Members of Congress who traded MPWR
From periodic transaction reports that name the company's stock. Amounts are the sums of the ranges as filed. Every row is on the MPWR page.
| Member | Seat | Trades | Bought | Sold | Range as filed | Latest |
|---|---|---|---|---|---|---|
| Markwayne Mullin | Senator (OK), Republican | 3 | 3 | 0 | $45K–$150K | February 4, 2026 |
| Byron Donalds | Representative (FL, District 19), Republican | 2 | 0 | 2 | $2,002–$30K | June 5, 2026 |
| Michael Guest | Representative (MS, District 3), Republican | 1 | 1 | 0 | $1,001–$15K | October 20, 2025 |
| Tommy Tuberville | Senator (AL), Republican | 1 | 0 | 1 | $1,001–$15K | May 3, 2024 |
Insider transactions
| Filer | Security | Side | Trade date | Disclosed | Lag | Shares | Price | Value | Flags | Source | Share |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Hsing Michael | MPWR | Sell S | September 28, 2026 | September 30, 2026 | 2d | 130 | $1,357 | $176K | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | September 28, 2026 | September 30, 2026 | 2d | 10,967 | $1,351 | $14.8M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | September 28, 2026 | September 30, 2026 | 2d | 6,343 | $1,347 | $8.5M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | September 28, 2026 | September 30, 2026 | 2d | 5,783 | $1,344 | $7.8M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | September 28, 2026 | September 30, 2026 | 2d | 2,949 | $1,339 | $3.9M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | September 28, 2026 | September 30, 2026 | 2d | 1,111 | $1,333 | $1.5M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | September 28, 2026 | September 30, 2026 | 2d | 2,121 | $1,329 | $2.8M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | September 28, 2026 | September 30, 2026 | 2d | 596 | $1,323 | $789K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Other G | August 31, 2026 | September 2, 2026 | 2d | 2,000 | — | — | indirect | Form 4 ↗ | |
| Tseng Saria | MPWR | Other G | August 31, 2026 | September 2, 2026 | 2d | 2,000 | — | — | Form 4 ↗ | ||
| DEAN ROBERT W II | MPWR | Other J | August 24, 2026 | August 26, 2026 | 2d | 5 | — | — | Form 4 ↗ | ||
| DEAN ROBERT W II | MPWR | Sell S | August 24, 2026 | August 26, 2026 | 2d | 32 | $1,298 | $42K | Form 4 ↗ | ||
| CHANG KUO WEI HERBERT | MPWR | Sell S | August 24, 2026 | August 25, 2026 | 1d | 50 | $1,282 | $64K | Form 4 ↗ | ||
| DEAN ROBERT W II | MPWR | Sell S | August 17, 2026 | August 19, 2026 | 2d | 6 | $1,414 | $8,482 | Form 4 ↗ | ||
| CHANG KUO WEI HERBERT | MPWR | Sell S | August 11, 2026 | August 13, 2026 | 2d | 50 | $1,420 | $71K | Form 4 ↗ | ||
| Sciammas Maurice | MPWR | Other G | August 4, 2026 | August 6, 2026 | 2d | 25,000 | — | — | indirect | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Other G | August 4, 2026 | August 6, 2026 | 2d | 25,000 | — | — | Form 4 ↗ | ||
| DEAN ROBERT W II | MPWR | Sell S | August 5, 2026 | August 6, 2026 | 1d | 105 | $1,344 | $141K | Form 4 ↗ | ||
| Sciammas Maurice | MPWR | Sell S | August 3, 2026 | August 5, 2026 | 2d | 30 | $1,344 | $40K | 10b5-1 planindirect | Form 4 ↗ | |
| DEAN ROBERT W II | MPWR | Other A | July 25, 2026 | July 28, 2026 | 3d | 1,359 | — | — | Form 4 ↗ | ||
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 110 | $1,406 | $155K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 117 | $1,400 | $164K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 213 | $1,396 | $297K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 50 | $1,388 | $69K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 410 | $1,384 | $567K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 418 | $1,379 | $576K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 472 | $1,375 | $649K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 240 | $1,369 | $329K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 50 | $1,359 | $68K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 5,640 | $1,353 | $7.6M | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 1,506 | $1,349 | $2.0M | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 1,864 | $1,344 | $2.5M | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 1,460 | $1,340 | $2.0M | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 776 | $1,335 | $1.0M | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 464 | $1,329 | $617K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 409 | $1,324 | $541K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 274 | $1,318 | $361K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 15, 2026 | July 17, 2026 | 2d | 527 | $1,314 | $692K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | July 1, 2026 | July 6, 2026 | 5d | 30 | $1,352 | $41K | late10b5-1 planindirect | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | June 1, 2026 | June 3, 2026 | 2d | 30 | $1,534 | $46K | 10b5-1 planindirect | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Other G | May 29, 2026 | June 2, 2026 | 4d | 12,472 | — | — | indirect | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | May 27, 2026 | May 29, 2026 | 2d | 7,565 | $1,700 | $12.9M | Form 4 ↗ | ||
| DEAN ROBERT W II | MPWR | Sell S | May 26, 2026 | May 28, 2026 | 2d | 22 | $1,650 | $36K | Form 4 ↗ | ||
| Zhou Jeff | MPWR | Sell S | May 26, 2026 | May 27, 2026 | 1d | 486 | $1,680 | $816K | Form 4 ↗ | ||
| Tseng Saria | MPWR | Sell S | May 22, 2026 | May 27, 2026 | 5d | 5,000 | $1,586 | $7.9M | late | Form 4 ↗ | |
| Tseng Saria | MPWR | Other G | May 22, 2026 | May 27, 2026 | 5d | 200 | — | — | late | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 130 | $1,521 | $198K | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 352 | $1,518 | $534K | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 551 | $1,513 | $834K | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 3,769 | $1,508 | $5.7M | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 2,929 | $1,503 | $4.4M | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 608 | $1,499 | $912K | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 862 | $1,491 | $1.3M | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 6,688 | $1,487 | $9.9M | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 5,737 | $1,483 | $8.5M | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 4,082 | $1,477 | $6.0M | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 5,049 | $1,473 | $7.4M | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 5,819 | $1,468 | $8.5M | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 3,424 | $1,463 | $5.0M | Form 4 ↗ | ||
| DEAN ROBERT W II | MPWR | Sell S | May 18, 2026 | May 20, 2026 | 2d | 4 | $1,563 | $6,253 | Form 4 ↗ | ||
| Sciammas Maurice | MPWR | Sell S | May 15, 2026 | May 19, 2026 | 4d | 50 | $1,586 | $79K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | May 15, 2026 | May 19, 2026 | 4d | 447 | $1,582 | $707K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | May 15, 2026 | May 19, 2026 | 4d | 703 | $1,578 | $1.1M | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | May 15, 2026 | May 19, 2026 | 4d | 1,312 | $1,571 | $2.1M | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | May 15, 2026 | May 19, 2026 | 4d | 2,020 | $1,567 | $3.2M | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | May 15, 2026 | May 19, 2026 | 4d | 2,010 | $1,562 | $3.1M | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | May 15, 2026 | May 19, 2026 | 4d | 1,717 | $1,557 | $2.7M | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | May 15, 2026 | May 19, 2026 | 4d | 3,741 | $1,550 | $5.8M | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Other G | May 13, 2026 | May 15, 2026 | 2d | 1,563 | — | — | indirect | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Other G | May 13, 2026 | May 15, 2026 | 2d | 1,563 | — | — | indirect | Form 4 ↗ | |
| DEAN ROBERT W II | MPWR | Other J | May 13, 2026 | May 15, 2026 | 2d | 2,156 | — | — | Form 4 ↗ | ||
| Elmiger Eugen J | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 514 | $1,600 | $822K | Form 4 ↗ | ||
| Elmiger Eugen J | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 2,619 | $1,596 | $4.2M | Form 4 ↗ | ||
| Elmiger Eugen J | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 1,355 | $1,591 | $2.2M | Form 4 ↗ | ||
| Elmiger Eugen J | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 2,587 | $1,587 | $4.1M | Form 4 ↗ | ||
| Elmiger Eugen J | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 1,879 | $1,582 | $3.0M | Form 4 ↗ | ||
| Elmiger Eugen J | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 834 | $1,576 | $1.3M | Form 4 ↗ | ||
| Elmiger Eugen J | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 1,078 | $1,572 | $1.7M | Form 4 ↗ | ||
| Elmiger Eugen J | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 814 | $1,566 | $1.3M | Form 4 ↗ | ||
| Elmiger Eugen J | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 320 | $1,560 | $499K | Form 4 ↗ | ||
| Xiao Deming | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 907 | $1,661 | $1.5M | Form 4 ↗ | ||
| Xiao Deming | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 11,597 | $1,658 | $19.2M | Form 4 ↗ | ||
| Xiao Deming | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 14,167 | $1,653 | $23.4M | Form 4 ↗ | ||
| Xiao Deming | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 3,329 | $1,648 | $5.5M | Form 4 ↗ | ||
| Wynne Eileen | MPWR | Sell S | May 6, 2026 | May 8, 2026 | 2d | 335 | $1,583 | $530K | Form 4 ↗ | ||
| Zhou Jeff | MPWR | Sell S | May 6, 2026 | May 6, 2026 | 0d | 500 | $1,650 | $825K | Form 4 ↗ | ||
| Zhou Jeff | MPWR | Sell S | May 5, 2026 | May 6, 2026 | 1d | 500 | $1,600 | $800K | Form 4 ↗ | ||
| Zhou Jeff | MPWR | Sell S | May 5, 2026 | May 6, 2026 | 1d | 514 | $1,574 | $809K | Form 4 ↗ | ||
| Sciammas Maurice | MPWR | Sell S | May 5, 2026 | May 6, 2026 | 1d | 380 | $1,584 | $602K | indirect | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | May 4, 2026 | May 6, 2026 | 2d | 30 | $1,589 | $48K | 10b5-1 planindirect | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 8, 2026 | April 10, 2026 | 2d | 120 | $1,322 | $159K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 8, 2026 | April 10, 2026 | 2d | 840 | $1,319 | $1.1M | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 8, 2026 | April 10, 2026 | 2d | 4,244 | $1,313 | $5.6M | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 8, 2026 | April 10, 2026 | 2d | 1,279 | $1,308 | $1.7M | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 8, 2026 | April 10, 2026 | 2d | 800 | $1,303 | $1.0M | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 8, 2026 | April 10, 2026 | 2d | 400 | $1,292 | $517K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 8, 2026 | April 10, 2026 | 2d | 120 | $1,287 | $154K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 8, 2026 | April 10, 2026 | 2d | 240 | $1,280 | $307K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 8, 2026 | April 10, 2026 | 2d | 360 | $1,270 | $457K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 8, 2026 | April 10, 2026 | 2d | 560 | $1,266 | $709K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 6, 2026 | April 8, 2026 | 2d | 1,396 | $1,180 | $1.6M | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 6, 2026 | April 8, 2026 | 2d | 1,680 | $1,176 | $2.0M | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 6, 2026 | April 8, 2026 | 2d | 2,036 | $1,170 | $2.4M | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 6, 2026 | April 8, 2026 | 2d | 684 | $1,166 | $797K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 6, 2026 | April 8, 2026 | 2d | 560 | $1,160 | $649K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 6, 2026 | April 8, 2026 | 2d | 480 | $1,149 | $552K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 6, 2026 | April 8, 2026 | 2d | 556 | $1,144 | $636K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 6, 2026 | April 8, 2026 | 2d | 244 | $1,140 | $278K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 1, 2026 | April 3, 2026 | 2d | 292 | $1,137 | $332K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 1, 2026 | April 3, 2026 | 2d | 188 | $1,136 | $214K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 1, 2026 | April 3, 2026 | 2d | 160 | $1,134 | $181K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 1, 2026 | April 3, 2026 | 2d | 184 | $1,132 | $208K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | April 1, 2026 | April 3, 2026 | 2d | 576 | $1,131 | $652K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | April 1, 2026 | April 3, 2026 | 2d | 30 | $1,116 | $33K | 10b5-1 planindirect | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | March 30, 2026 | April 1, 2026 | 2d | 80 | $1,041 | $83K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | March 30, 2026 | April 1, 2026 | 2d | 166 | $1,036 | $172K | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | March 30, 2026 | April 1, 2026 | 2d | 2,440 | $1,029 | $2.5M | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | March 30, 2026 | April 1, 2026 | 2d | 2,200 | $1,023 | $2.3M | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | March 30, 2026 | April 1, 2026 | 2d | 3,194 | $1,017 | $3.2M | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | March 30, 2026 | April 1, 2026 | 2d | 3,360 | $1,010 | $3.4M | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | March 30, 2026 | April 1, 2026 | 2d | 9,080 | $1,005 | $9.1M | 10b5-1 plan | Form 4 ↗ | |
| Tseng Saria | MPWR | Sell S | March 30, 2026 | April 1, 2026 | 2d | 5,154 | $1,001 | $5.2M | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | March 20, 2026 | March 24, 2026 | 4d | 30 | $1,095 | $33K | 10b5-1 planindirect | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 12, 2026 | February 17, 2026 | 5d | 1,440 | $1,217 | $1.8M | late10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 12, 2026 | February 17, 2026 | 5d | 1,240 | $1,210 | $1.5M | late10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 12, 2026 | February 17, 2026 | 5d | 3,640 | $1,206 | $4.4M | late10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 12, 2026 | February 17, 2026 | 5d | 1,440 | $1,201 | $1.7M | late10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 12, 2026 | February 17, 2026 | 5d | 600 | $1,194 | $717K | late10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 12, 2026 | February 17, 2026 | 5d | 160 | $1,188 | $190K | late10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 12, 2026 | February 17, 2026 | 5d | 480 | $1,181 | $567K | late10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 12, 2026 | February 17, 2026 | 5d | 200 | $1,173 | $235K | late10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 12, 2026 | February 17, 2026 | 5d | 2,076 | $1,169 | $2.4M | late10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 12, 2026 | February 17, 2026 | 5d | 4,001 | $1,165 | $4.7M | late10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 12, 2026 | February 17, 2026 | 5d | 4,992 | $1,160 | $5.8M | late10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 12, 2026 | February 17, 2026 | 5d | 12,731 | $1,156 | $14.7M | late10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 11, 2026 | February 13, 2026 | 2d | 649 | $1,202 | $780K | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 11, 2026 | February 13, 2026 | 2d | 14,578 | $1,197 | $17.5M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 11, 2026 | February 13, 2026 | 2d | 6,079 | $1,193 | $7.3M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 11, 2026 | February 13, 2026 | 2d | 2,104 | $1,188 | $2.5M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 11, 2026 | February 13, 2026 | 2d | 1,542 | $1,183 | $1.8M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 11, 2026 | February 13, 2026 | 2d | 2,799 | $1,178 | $3.3M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 11, 2026 | February 13, 2026 | 2d | 1,987 | $1,173 | $2.3M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 11, 2026 | February 13, 2026 | 2d | 1,533 | $1,168 | $1.8M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 11, 2026 | February 13, 2026 | 2d | 1,366 | $1,164 | $1.6M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 11, 2026 | February 13, 2026 | 2d | 363 | $1,159 | $421K | 10b5-1 plan | Form 4 ↗ | |
| Sciammas Maurice | MPWR | Sell S | February 11, 2026 | February 12, 2026 | 1d | 200 | $1,180 | $236K | indirect | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 10, 2026 | February 12, 2026 | 2d | 280 | $1,197 | $335K | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 10, 2026 | February 12, 2026 | 2d | 880 | $1,176 | $1.0M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 10, 2026 | February 12, 2026 | 2d | 360 | $1,161 | $418K | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 10, 2026 | February 12, 2026 | 2d | 694 | $1,155 | $802K | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 10, 2026 | February 12, 2026 | 2d | 1,215 | $1,151 | $1.4M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 10, 2026 | February 12, 2026 | 2d | 3,864 | $1,146 | $4.4M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 10, 2026 | February 12, 2026 | 2d | 16,080 | $1,142 | $18.4M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 10, 2026 | February 12, 2026 | 2d | 6,325 | $1,137 | $7.2M | 10b5-1 plan | Form 4 ↗ | |
| Hsing Michael | MPWR | Sell S | February 10, 2026 | February 12, 2026 | 2d | 4,302 | $1,132 | $4.9M | 10b5-1 plan | Form 4 ↗ | |
| Lee Victor K | MPWR | Sell S | February 9, 2026 | February 11, 2026 | 2d | 400 | $1,212 | $485K | 10b5-1 plan | Form 4 ↗ | |
| Xiao Deming | MPWR | Sell S | February 6, 2026 | February 10, 2026 | 4d | 22,875 | $1,171 | $26.8M | Form 4 ↗ | ||
| Tseng Saria | MPWR | Sell S | February 6, 2026 | February 10, 2026 | 4d | 22,875 | $1,171 | $26.8M | Form 4 ↗ | ||
| Sciammas Maurice | MPWR | Sell S | February 6, 2026 | February 10, 2026 | 4d | 22,875 | $1,171 | $26.8M | Form 4 ↗ | ||
| BLEGEN THEODORE | MPWR | Sell S | February 6, 2026 | February 10, 2026 | 4d | 21,725 | $1,171 | $25.4M | Form 4 ↗ | ||
| Hsing Michael | MPWR | Sell S | February 6, 2026 | February 10, 2026 | 4d | 54,923 | $1,171 | $64.3M | Form 4 ↗ | ||
| Wynne Eileen | MPWR | Other A | February 3, 2026 | February 5, 2026 | 2d | 189 | — | — | Form 4 ↗ | ||
| Zhou Jeff | MPWR | Other A | February 3, 2026 | February 5, 2026 | 2d | 189 | — | — | Form 4 ↗ | ||
| CHANG KUO WEI HERBERT | MPWR | Other A | February 3, 2026 | February 5, 2026 | 2d | 189 | — | — | Form 4 ↗ | ||
| Elmiger Eugen J | MPWR | Other A | February 3, 2026 | February 5, 2026 | 2d | 189 | — | — | Form 4 ↗ | ||
| Lee Victor K | MPWR | Other A | February 3, 2026 | February 5, 2026 | 2d | 189 | — | — | Form 4 ↗ | ||
| Martinez Carintia | MPWR | Other A | February 3, 2026 | February 5, 2026 | 2d | 189 | — | — | Form 4 ↗ | ||
| Xiao Deming | MPWR | Other A | February 3, 2026 | February 5, 2026 | 2d | 57,170 | — | — | Form 4 ↗ | ||
| BLEGEN THEODORE | MPWR | Other A | February 3, 2026 | February 5, 2026 | 2d | 38,745 | — | — | Form 4 ↗ | ||
| Tseng Saria | MPWR | Other A | February 3, 2026 | February 5, 2026 | 2d | 57,170 | — | — | Form 4 ↗ | ||
| Hsing Michael | MPWR | Other A | February 3, 2026 | February 5, 2026 | 2d | 136,825 | — | — | Form 4 ↗ | ||
| Sciammas Maurice | MPWR | Other A | February 3, 2026 | February 5, 2026 | 2d | 57,170 | — | — | Form 4 ↗ | ||
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 80 | $1,139 | $91K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 80 | $1,138 | $91K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 120 | $1,136 | $136K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 120 | $1,135 | $136K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 241 | $1,134 | $273K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 379 | $1,133 | $430K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 322 | $1,133 | $365K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 198 | $1,132 | $224K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 320 | $1,130 | $362K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 240 | $1,129 | $271K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 240 | $1,128 | $271K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 80 | $1,127 | $90K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 200 | $1,127 | $225K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 40 | $1,123 | $45K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 80 | $1,121 | $90K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 40 | $1,117 | $45K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | February 2, 2026 | February 4, 2026 | 2d | 220 | $1,111 | $244K | 10b5-1 plan | Form 4 ↗ | |
| Lee Victor K | MPWR | Sell S | January 2, 2026 | January 6, 2026 | 4d | 600 | $931 | $559K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | January 2, 2026 | January 6, 2026 | 4d | 80 | $947 | $76K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | January 2, 2026 | January 6, 2026 | 4d | 40 | $945 | $38K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | January 2, 2026 | January 6, 2026 | 4d | 650 | $944 | $614K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | January 2, 2026 | January 6, 2026 | 4d | 539 | $944 | $509K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | January 2, 2026 | January 6, 2026 | 4d | 74 | $942 | $70K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | January 2, 2026 | January 6, 2026 | 4d | 406 | $942 | $382K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | January 2, 2026 | January 6, 2026 | 4d | 40 | $940 | $38K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | January 2, 2026 | January 6, 2026 | 4d | 117 | $940 | $110K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | January 2, 2026 | January 6, 2026 | 4d | 460 | $939 | $432K | 10b5-1 plan | Form 4 ↗ | |
| BLEGEN THEODORE | MPWR | Sell S | January 2, 2026 | January 6, 2026 | 4d | 120 | $937 | $112K | 10b5-1 plan | Form 4 ↗ |
Showing the 200 most recent of 367.
Federal contracts (USAspending, awards started in the last 180 days)
No contract award starting in the last 180 days was found for a recipient named exactly "MONOLITHIC POWER SYSTEMS INC". Subsidiaries and differently-spelled recipients are not matched — search contracts.
Lobbying (Senate LDA, as client)
No LDA filing posted since October 2025 names "MONOLITHIC POWER SYSTEMS INC" as the client. Filings under a subsidiary or trade-association name are not matched — search lobbying.
Related companies
Companies whose stock was traded by the same people who traded MPWR, by number of filers in common. It shows overlap in public filings and nothing else.
- ELI LILLY & Co LLY 3 filers in common
- CHEVRON CORP CVX 3 filers in common
- NETFLIX INC NFLX 2 filers in common
- INTUIT INC. INTU 2 filers in common
- ADOBE INC. ADBE 2 filers in common
- ServiceNow, Inc. NOW 2 filers in common
- Accenture plc ACN 2 filers in common
- Alphabet Inc. GOOGL 2 filers in common
Guides for this page
- What is SEC Form 4? Who files: officers, directors and owners of more than 10% of a class of the company's shares.
- Insider buying vs insider selling Selling outweighs buying by a wide margin in normal times.
- What disclosure data cannot tell you Filings are late by design: up to 45 days for Congress, two business days for insiders.
Sources and method
| Source | Filings | Rows | First filed | Newest filed | Read the originals |
|---|---|---|---|---|---|
| House Clerk, periodic transaction reports | 2 | 3 | November 19, 2025 | July 15, 2026 | House Clerk search |
| Senate eFD, periodic transaction reports | 3 | 4 | February 4, 2026 | August 5, 2026 | Senate eFD search |
| SEC EDGAR, Form 4 | 88 | 367 | October 1, 2025 | September 30, 2026 | Form 4 list on EDGAR |
Site built October 22, 2026. Every row in the tables above links to its own filing. To quote a figure, use the Cite button at the top of the page; see how to cite and reuse.
Insiders and their transactions come from SEC EDGAR Form 4 filings for this issuer. Contracts and lobbying are matched by exact normalized name (suffixes like Inc./Corp. ignored) to USAspending recipients and LDA clients — a conservative match that misses subsidiaries on purpose. See methodology and corrections.
Not investment advice. Public records shown as filed; no recommendation is made or implied.