Monolithic Power Systems, Inc.
MPWRLast close · Oct 16, 20261,210.86−38.34 (−3.07%)
Market cap$59.5B
Between Jun 1, 2026 and Sep 28, 2026, Monolithic Power Systems (MPWR) insiders filed 40 Form 4 transactions: 34 sales worth $61.0M in total and no open-market purchase; 29 of the sales were under 10b5-1 plans set in advance. The largest seller was Hsing Michael, $14.8M. 6 other filings were grants, exercises or gifts, which say nothing about buying or selling.
40
0
34
29
Form 4 transactions
| Date | Insider | Title | Code | Plan | Shares | Price | Value |
|---|---|---|---|---|---|---|---|
| 2026-09-28 | Hsing Michael | CEO | S | 10b5-1 | 130 | 1,356.94 | $176,402.2 |
| 2026-09-28 | Hsing Michael | CEO | S | 10b5-1 | 10,967 | 1,351.43 | $14.8M |
| 2026-09-28 | Hsing Michael | CEO | S | 10b5-1 | 6,343 | 1,347.15 | $8.5M |
| 2026-09-28 | Hsing Michael | CEO | S | 10b5-1 | 5,783 | 1,343.76 | $7.8M |
| 2026-09-28 | Hsing Michael | CEO | S | 10b5-1 | 2,949 | 1,338.66 | $3.9M |
| 2026-09-28 | Hsing Michael | CEO | S | 10b5-1 | 1,111 | 1,333.34 | $1.5M |
| 2026-09-28 | Hsing Michael | CEO | S | 10b5-1 | 2,121 | 1,328.54 | $2.8M |
| 2026-09-28 | Hsing Michael | CEO | S | 10b5-1 | 596 | 1,323.31 | $788,692.8 |
| 2026-08-31 | Tseng Saria | EVP & General Counsel | G | 2,000 | 0.00 | $0 | |
| 2026-08-31 | Tseng Saria | EVP & General Counsel | G | 2,000 | 0.00 | $0 | |
| 2026-08-24 | DEAN ROBERT W II | Interim CFO | S | 32 | 1,297.72 | $41,527 | |
| 2026-08-24 | DEAN ROBERT W II | Interim CFO | J | 5 | 0.00 | $0 | |
| 2026-08-24 | CHANG KUO WEI HERBERT | Director | S | 50 | 1,281.57 | $64,078.5 | |
| 2026-08-17 | DEAN ROBERT W II | Interim CFO | S | 6 | 1,413.64 | $8,481.8 | |
| 2026-08-11 | CHANG KUO WEI HERBERT | Director | S | 50 | 1,420.00 | $71,000 | |
| 2026-08-04 | Sciammas Maurice | EVP, WW Sales & Marketing | G | 25,000 | 0.00 | $0 | |
| 2026-08-04 | Sciammas Maurice | EVP, WW Sales & Marketing | G | 25,000 | 0.00 | $0 | |
| 2026-08-05 | DEAN ROBERT W II | Interim CFO | S | 105 | 1,344.27 | $141,148.4 | |
| 2026-08-03 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 30 | 1,343.94 | $40,318.2 |
| 2026-07-25 | DEAN ROBERT W II | Interim CFO | A | 1,359 | 0.00 | $0 | |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 527 | 1,314.03 | $692,493.8 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 274 | 1,318.42 | $361,247.1 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 409 | 1,323.93 | $541,487.4 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 464 | 1,329.30 | $616,795.2 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 776 | 1,334.59 | $1.0M |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 1,460 | 1,339.59 | $2.0M |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 1,864 | 1,344.16 | $2.5M |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 1,506 | 1,348.91 | $2.0M |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 5,640 | 1,352.95 | $7.6M |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 50 | 1,359.36 | $67,968 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 240 | 1,369.18 | $328,603.2 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 472 | 1,375.47 | $649,221.8 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 418 | 1,378.73 | $576,309.1 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 410 | 1,384.11 | $567,485.1 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 50 | 1,388.19 | $69,409.5 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 213 | 1,396.16 | $297,382.1 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 117 | 1,400.45 | $163,852.7 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 110 | 1,405.71 | $154,628.1 |
| 2026-07-01 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 30 | 1,351.61 | $40,548.3 |
| 2026-06-01 | Sciammas Maurice | EVP, WW Sales & Marketing | S | 10b5-1 | 30 | 1,533.95 | $46,018.5 |
Codes are the SEC's: P open-market purchase, S open-market sale; M exercise, F tax withholding, A grant and G gift are routine. A 10b5-1 flag means the trade ran under a plan adopted in advance. Method notes in where the numbers come from.