MONOLITHIC POWER SYSTEMS INC — Insider Transactions
Form 4 filings by directors, officers, and 10%+ shareholders
SEC rules require corporate insiders — including directors, executive officers, and any shareholder owning more than 10% of a company's shares — to report changes in their ownership within two business days of a transaction. These disclosures are filed as Form 4. Open-market purchases (code P) are generally considered the most meaningful signal, as insiders are spending their own money.
| Insider | Title | Type | Shares | Price | Value | Owns After | Date |
|---|---|---|---|---|---|---|---|
| Tseng Saria | EVP & General Counsel | Gift | 1,000 | — | — | 1,000 | Dec 24, 2025 |
| Lee Victor K | — | Sale | 197 | $949.70 | $187,091 | 29,370 | Dec 24, 2025 |
| Hsing Michael | CEO | Gift | 12,337 | — | — | 906,332 | Dec 9, 2025 |
| BLEGEN THEODORE | EVP and CFO | Sale | 120 | $904.38 | $108,526 | 74,012 | Dec 1, 2025 |
| Tseng Saria | EVP & General Counsel | Sale | 1,845 | $927.41 | $1,711,071 | 171,233 | Nov 26, 2025 |
| Tseng Saria | EVP & General Counsel | Sale | 10,200 | $907.21 | $9,253,542 | 189,698 | Nov 25, 2025 |
| CHANG KUO WEI HERBERT | — | Sale | 100 | $896.97 | $89,697 | 426 | Nov 25, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Sale | 3,976 | $895.23 | $3,559,434 | 144,330 | Nov 24, 2025 |
| CHANG KUO WEI HERBERT | — | Sale | 100 | $873.97 | $87,397 | 526 | Nov 21, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Sale | 3,776 | $880.58 | $3,325,070 | 165,329 | Nov 19, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Sale | 220 | $871.45 | $191,719 | 178,723 | Nov 19, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Gift | 4,530 | — | — | 26,660 | Nov 13, 2025 |
| Hsing Michael | CEO | Sale | 1,904 | $961.63 | $1,830,944 | 949,720 | Nov 12, 2025 |
| Hsing Michael | CEO | Sale | 1,894 | $963.41 | $1,824,699 | 958,129 | Nov 11, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Sale | 200 | $986.81 | $197,362 | 1,299 | Nov 5, 2025 |
| BLEGEN THEODORE | EVP and CFO | Sale | 47 | $1,038.41 | $48,805 | 74,332 | Nov 3, 2025 |
| Hsing Michael | CEO | Tax Withholding | 121,918 | $1,096.63 | $133,698,936 | 995,669 | Oct 30, 2025 |
| BLEGEN THEODORE | EVP and CFO | Tax Withholding | 48,298 | $1,096.63 | $52,965,036 | 77,332 | Oct 30, 2025 |
| Tseng Saria | EVP & General Counsel | Tax Withholding | 54,543 | $1,096.63 | $59,813,490 | 207,331 | Oct 30, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Tax Withholding | 54,543 | $1,096.63 | $59,813,490 | 183,306 | Oct 30, 2025 |
| Xiao Deming | EVP, Global Operations | Tax Withholding | 54,543 | $1,096.63 | $59,813,490 | 201,637 | Oct 30, 2025 |
| Tseng Saria | EVP & General Counsel | Award / Grant | 135,520 | — | — | 261,874 | Oct 25, 2025 |
| BLEGEN THEODORE | EVP and CFO | Award / Grant | 87,690 | — | — | 125,630 | Oct 25, 2025 |
| Hsing Michael | CEO | Award / Grant | 302,920 | — | — | 1,117,587 | Oct 25, 2025 |
| Xiao Deming | EVP, Global Operations | Award / Grant | 135,520 | — | — | 256,180 | Oct 25, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Award / Grant | 135,520 | — | — | 237,849 | Oct 25, 2025 |
| Tseng Saria | EVP & General Counsel | Sale | 1,300 | $1,087.62 | $1,413,906 | 126,354 | Oct 24, 2025 |
| Tseng Saria | EVP & General Counsel | Sale | 1,313 | $1,030.81 | $1,353,454 | 127,654 | Oct 15, 2025 |
| BLEGEN THEODORE | EVP and CFO | Sale | 60 | $904.00 | $54,240 | 40,833 | Oct 1, 2025 |
| Martinez Carintia | — | Sale | 1,400 | $900.00 | $1,260,000 | 878 | Sep 18, 2025 |
| Tseng Saria | EVP & General Counsel | Sale | 14,510 | $914.45 | $13,268,670 | 144,494 | Sep 18, 2025 |
| BLEGEN THEODORE | EVP and CFO | Sale | 100 | $808.53 | $80,853 | 43,439 | Sep 2, 2025 |
| Elmiger Eugen J | — | Sale | 900 | $847.30 | $762,570 | 18,113 | Aug 29, 2025 |
| Zhou Jeff | — | Sale | 193 | $870.00 | $167,910 | 5,611 | Aug 27, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Gift | 1,499 | — | — | 12,228 | Aug 19, 2025 |
| Hsing Michael | CEO | Sale | 2,100 | $830.46 | $1,743,966 | 819,265 | Aug 15, 2025 |
| Zhou Jeff | — | Sale | 400 | $850.00 | $340,000 | 5,804 | Aug 13, 2025 |
| Zhou Jeff | — | Sale | 200 | $830.00 | $166,000 | 6,204 | Aug 12, 2025 |
| Xiao Deming | EVP, Global Operations | Gift | 945 | — | — | 4,336 | Aug 11, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Gift | 4,836 | — | — | 44,930 | Aug 6, 2025 |
| Xiao Deming | EVP, Global Operations | Sale | 39,999 | $780.00 | $31,199,220 | 121,605 | Aug 1, 2025 |
| BLEGEN THEODORE | EVP and CFO | Sale | 3,000 | $750.00 | $2,250,000 | 43,939 | Aug 1, 2025 |
| BLEGEN THEODORE | EVP and CFO | Sale | 6,000 | $750.00 | $4,500,000 | 46,939 | Jul 1, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Gift | 1,499 | — | — | 15,727 | May 28, 2025 |
| CHANG KUO WEI HERBERT | — | Sale | 50 | $738.00 | $36,900 | 626 | May 13, 2025 |
| CHANG KUO WEI HERBERT | — | Sale | 100 | $698.00 | $69,800 | 676 | May 12, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Sale | 12,000 | $701.00 | $8,412,000 | 4,015 | May 12, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Gift | 1,878 | — | — | 17,226 | May 9, 2025 |
| CHANG KUO WEI HERBERT | — | Sale | 100 | $650.00 | $65,000 | 776 | May 8, 2025 |
| Sciammas Maurice | EVP, WW Sales & Marketing | Gift | 1,102 | — | — | 19,104 | Feb 18, 2025 |