MPWR (Monolithic Power Systems, Inc.)
Insider Trading Activity
Every open-market purchase and sale reported by MPWR officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.
Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.
| Filed | Insider | Role | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-09-02 | Saria Tseng | EVP & General Counsel | G | — | — |
| 2026-08-26 | ROBERT W DEAN II | Interim CFO | MIXED | — | — |
| 2026-08-25 | KUO WEI HERBERT CHANG | Director | Sell | — | — |
| 2026-08-19 | ROBERT W DEAN II | Interim CFO | Sell | — | — |
| 2026-08-13 | KUO WEI HERBERT CHANG | Director | Sell | — | — |
| 2026-08-06 | ROBERT W DEAN II | Interim CFO | Sell | — | — |
| 2026-08-06 | Maurice Sciammas | EVP, WW Sales & Marketing | G | — | — |
| 2026-08-06 | ROBERT W DEAN II | Interim CFO | Sell | — | — |
| 2026-08-06 | Maurice Sciammas | EVP, WW Sales & Marketing | G | — | — |
| 2026-08-05 | Maurice Sciammas | EVP, WW Sales & Marketing | Sell | — | — |
| 2026-07-28 | ROBERT W DEAN II | Interim CFO | A | — | — |
| 2026-07-17 | Maurice Sciammas | EVP, WW Sales & Marketing | Sell | — | — |
| 2026-07-06 | Maurice Sciammas | EVP, WW Sales & Marketing | Sell | — | — |
| Insider | Role | Shares Held | Value |
|---|---|---|---|
| — | EVP & General Counsel | 143,218 | — |
| — | EVP, WW Sales & Marketing | 128,343 | — |
| — | Interim CFO | 7,154 | — |
| — | Director | 515 | — |
Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.
Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.
Full filing history and per-insider positions are on the MPWR quote page; the site-wide leaderboard is on the insider transactions hub.