12 insiders reported 402 Form 4 transactions for MONOLITHIC POWER SYSTEMS INC (MPWR) over the past 18 months (most recent 2026-08-19). Recent activity: DEAN ROBERT W II (Interim CFO) Sell 6 shares, CHANG KUO WEI HERBERT (Director) Sell 50 shares, Sciammas Maurice (EVP, WW Sales & Marketing) Sell 25,000 shares, DEAN ROBERT W II (Interim CFO) Sell 105 shares, Sciammas Maurice (EVP, WW Sales & Marketing) Buy 25,000 shares. Source: SEC Form 4.
| Date | Insider | Title | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-08-19 | DEAN ROBERT W II | Interim CFO | Sell | 6 | $8,482 |
| 2026-08-13 | CHANG KUO WEI HERBERT | Director | Sell | 50 | $71,000 |
| 2026-08-06 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 25,000 | $0 |
| 2026-08-06 | DEAN ROBERT W II | Interim CFO | Sell | 105 | $141,148 |
| 2026-08-06 | Sciammas Maurice | EVP, WW Sales & Marketing | Buy | 25,000 | $0 |
| 2026-08-05 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 30 | $40,318 |
| 2026-07-28 | DEAN ROBERT W II | Interim CFO | Buy | 1,359 | $0 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 1,460 | $2.0M |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 274 | $361,247 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 409 | $541,487 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 464 | $616,795 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 776 | $1.0M |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 527 | $692,494 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 1,864 | $2.5M |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 1,506 | $2.0M |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 5,640 | $7.6M |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 50 | $67,968 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 240 | $328,603 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 472 | $649,222 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 418 | $576,309 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 110 | $154,628 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 50 | $69,410 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 213 | $297,382 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 117 | $163,853 |
| 2026-07-17 | Sciammas Maurice | EVP, WW Sales & Marketing | Sell | 410 | $567,485 |
Source: SEC Form 4 filings · as of 2026-08-19