Monolithic Power Systems, Inc. (MPWR) Insider Trading
Over the last 3 months, MPWR insiders made 0 open-market buys and 25 sales, a net sale of -$20.6M (SEC Form 4). Over the last 6 months, 803 institutions increased and 890 reduced their position (13F).
Insider Activity
Sentiment
0/100
Buys (3m)
0
Sells (3m)
25
Net (3m)
-$20.6M
Insider trades by month Buys Sells
Mar
Apr
May
Jun
Jul
Aug
Context3-month price -18.4%Institutions accumulating (13F)
| Date | Insider | Type | Shares | Price |
|---|---|---|---|---|
| Aug 26, 2026 | DEAN ROBERT W IIofficer: Interim CFO | Sell | 32 | $1297.72 |
| Aug 25, 2026 | CHANG KUO WEI HERBERTdirector | Sell | 50 | $1281.57 |
| Aug 19, 2026 | DEAN ROBERT W IIofficer: Interim CFO | Sell | 6 | $1413.64 |
| Aug 13, 2026 | CHANG KUO WEI HERBERTdirector | Sell | 50 | $1420.00 |
| Aug 6, 2026 | DEAN ROBERT W IIofficer: Interim CFO | Sell | 105 | $1344.27 |
| Aug 5, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 30 | $1343.94 |
| Jul 28, 2026 | DEAN ROBERT W IIofficer: Interim CFO | Grant | 1,359 | — |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 117 | $1400.45 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 1,506 | $1348.91 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 50 | $1359.36 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 527 | $1314.03 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 274 | $1318.42 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 410 | $1384.11 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 110 | $1405.71 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 5,640 | $1352.95 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 409 | $1323.93 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 776 | $1334.59 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 213 | $1396.16 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 240 | $1369.18 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 1,460 | $1339.59 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 1,864 | $1344.16 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 464 | $1329.30 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 472 | $1375.47 |
| Jul 17, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 418 | $1378.73 |
| Jul 6, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 30 | $1351.61 |
| Jun 3, 2026 | Sciammas Mauriceofficer: EVP, WW Sales & Marketing | Sell | 30 | $1533.95 |
| May 29, 2026 | Tseng Sariaofficer: EVP & General Counsel | Sell | 7,565 | $1700.00 |
| May 28, 2026 | DEAN ROBERT W IIofficer: Interim CFO | Sell | 22 | $1649.56 |
| May 27, 2026 | Tseng Sariaofficer: EVP & General Counsel | Sell | 5,000 | $1586.43 |
| May 27, 2026 | Zhou Jeffdirector | Sell | 486 | $1680.00 |
Source: MPWR SEC Form 4 filings, latest Aug 26, 2026. For informational purposes only — not investment advice.
Institutional activity (13F)
How institutions changed their MPWR positions over the last 6 months (SEC Form 13F).
Increased
803
New positions
402
Reduced
890
Sold out
86
Largest moves
| Institution | Action | Shares | Filed |
|---|---|---|---|
| BLACKROCK, INC. | Increased | 6.1M | May 13, 2026 |
| BlackRock, Inc. | Reduced | 5.6M | Aug 7, 2026 |
| FMR LLC | Increased | 5.2M | Aug 13, 2026 |
| FMR LLC | Increased | 4.4M | May 15, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | Increased | 3.1M | Aug 13, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | New Position | 3.1M | May 15, 2026 |
| VANGUARD PORTFOLIO MANAGEMENT LLC | New Position | 2.5M | May 8, 2026 |
| VANGUARD PORTFOLIO MANAGEMENT LLC | Reduced | 2.5M | Aug 13, 2026 |
| Invesco Ltd. | Increased | 2.3M | Aug 14, 2026 |
| STATE STREET CORP | Increased | 2.3M | Aug 7, 2026 |
| STATE STREET CORP | Increased | 2.2M | May 15, 2026 |
| GEODE CAPITAL MANAGEMENT, LLC | Increased | 1.4M | May 15, 2026 |
| PRICE T ROWE ASSOCIATES INC /MD/ | Reduced | 1.3M | May 15, 2026 |
| GEODE CAPITAL MANAGEMENT, LLC | Reduced | 1.2M | Aug 12, 2026 |
| INVESCO LTD. | Reduced | 1.0M | Jul 15, 2026 |
Source: SEC Form 13F filings. For informational purposes only — not investment advice.