As of the latest Form 4 filed Jun 3, 2026.
What Monolithic Power Systems Inc insiders — officers, directors and 10% owners — have bought and sold in their own stock, straight from their SEC Form 4 filings. Values are shares × the reported transaction price where both are disclosed.
Buys plotted up, sells down; bar height is the disclosed dollar value (shares × reported price). Our Form 4 history is only complete from mid-2026, so early months are sparse — the series fills in as more filings land. Open-market purchases and sales only.
Newest filing first — the 124 most recent filings for MPWR.
| Filed | Trade date | Insider | Transaction | Shares | Price | Value | 10b5-1 | Filing |
|---|---|---|---|---|---|---|---|---|
| 2026-06-03 | 2026-06-01 | Sciammas Maurice EVP, WW Sales & Marketing | SSale | −30.00 | $1,533.95 | $46.0K | Yes (planned) | Form 4 ↗ |
| 2026-06-02 | 2026-05-29 | Sciammas Maurice EVP, WW Sales & Marketing | GGift | −12.5K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-05-29 | 2026-05-27 | Tseng Saria EVP & General Counsel | SSale | −7.57K | $1,700.00 | $12.9M | No | Form 4 ↗ |
| 2026-05-28 | 2026-05-26 | DEAN ROBERT W II Interim CFO | SSale | −22.00 | $1,649.56 | $36.3K | No | Form 4 ↗ |
| 2026-05-27 | 2026-05-26 | Zhou Jeff Director | SSale | −486.00 | $1,680.00 | $816K | No | Form 4 ↗ |
| 2026-05-27 | 2026-05-22 | Tseng Saria EVP & General Counsel | SSale | −5.00K | $1,586.43 | $7.93M | No | Form 4 ↗ |
| 2026-05-27 | 2026-05-22 | Tseng Saria, EVP & General Counsel | GGift | −200.00 | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael CEO | SSale | −130.00 | $1,521.43 | $198K | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael, CEO | SSale | −352.00 | $1,518.15 | $534K | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael, CEO | SSale | −551.00 | $1,513.11 | $834K | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael, CEO | SSale | −3.77K | $1,507.70 | $5.68M | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael, CEO | SSale | −2.93K | $1,503.05 | $4.40M | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael, CEO | SSale | −608.00 | $1,499.46 | $912K | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael, CEO | SSale | −862.00 | $1,491.48 | $1.29M | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael, CEO | SSale | −6.69K | $1,486.76 | $9.94M | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael, CEO | SSale | −5.74K | $1,482.51 | $8.51M | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael, CEO | SSale | −4.08K | $1,476.96 | $6.03M | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael, CEO | SSale | −5.05K | $1,472.84 | $7.44M | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael, CEO | SSale | −5.82K | $1,467.62 | $8.54M | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | Hsing Michael, CEO | SSale | −3.42K | $1,462.61 | $5.01M | No | Form 4 ↗ |
| 2026-05-20 | 2026-05-18 | DEAN ROBERT W II Interim CFO | SSale | −4.00 | $1,563.28 | $6.25K | No | Form 4 ↗ |
| 2026-05-15 | 2026-05-13 | Sciammas Maurice EVP, WW Sales & Marketing | GGift | +1.56K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-05-15 | 2026-05-13 | Sciammas Maurice, EVP, WW Sales & Marketing | GGift | −1.56K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-05-15 | 2026-05-13 | DEAN ROBERT W II Interim CFO | JOther | −2.16K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Elmiger Eugen J Director | SSale | −514.00 | $1,600.14 | $822K | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Elmiger Eugen J, Director | SSale | −2.62K | $1,596.42 | $4.18M | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Elmiger Eugen J, Director | SSale | −1.35K | $1,591.38 | $2.16M | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Elmiger Eugen J, Director | SSale | −2.59K | $1,586.81 | $4.11M | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Elmiger Eugen J, Director | SSale | −1.88K | $1,581.81 | $2.97M | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Elmiger Eugen J, Director | SSale | −834.00 | $1,575.57 | $1.31M | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Elmiger Eugen J, Director | SSale | −1.08K | $1,571.58 | $1.69M | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Elmiger Eugen J, Director | SSale | −814.00 | $1,566.36 | $1.28M | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Elmiger Eugen J, Director | SSale | −320.00 | $1,559.88 | $499K | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Xiao Deming EVP, Global Operations | SSale | −907.00 | $1,661.38 | $1.51M | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Xiao Deming, EVP, Global Operations | SSale | −11.6K | $1,657.93 | $19.2M | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Xiao Deming, EVP, Global Operations | SSale | −14.2K | $1,652.80 | $23.4M | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Xiao Deming, EVP, Global Operations | SSale | −3.33K | $1,648.38 | $5.49M | No | Form 4 ↗ |
| 2026-05-08 | 2026-05-06 | Wynne Eileen Director | SSale | −335.00 | $1,582.68 | $530K | No | Form 4 ↗ |
| 2026-05-06 | 2026-05-06 | Zhou Jeff Director | SSale | −500.00 | $1,650.00 | $825K | No | Form 4 ↗ |
| 2026-05-06 | 2026-05-05 | Zhou Jeff, Director | SSale | −500.00 | $1,600.00 | $800K | No | Form 4 ↗ |
| 2026-05-06 | 2026-05-05 | Zhou Jeff, Director | SSale | −514.00 | $1,574.48 | $809K | No | Form 4 ↗ |
| 2026-05-06 | 2026-05-05 | Sciammas Maurice EVP, WW Sales & Marketing | SSale | −380.00 | $1,583.81 | $602K | No | Form 4 ↗ |
| 2026-05-06 | 2026-05-04 | Sciammas Maurice EVP, WW Sales & Marketing | SSale | −30.00 | $1,588.73 | $47.7K | Yes (planned) | Form 4 ↗ |
| 2026-04-10 | 2026-04-08 | Tseng Saria EVP & General Counsel | SSale | −120.00 | $1,321.94 | $159K | Yes (planned) | Form 4 ↗ |
| 2026-04-10 | 2026-04-08 | Tseng Saria, EVP & General Counsel | SSale | −840.00 | $1,319.25 | $1.11M | Yes (planned) | Form 4 ↗ |
| 2026-04-10 | 2026-04-08 | Tseng Saria, EVP & General Counsel | SSale | −4.24K | $1,312.82 | $5.57M | Yes (planned) | Form 4 ↗ |
| 2026-04-10 | 2026-04-08 | Tseng Saria, EVP & General Counsel | SSale | −1.28K | $1,308.30 | $1.67M | Yes (planned) | Form 4 ↗ |
| 2026-04-10 | 2026-04-08 | Tseng Saria, EVP & General Counsel | SSale | −800.00 | $1,302.52 | $1.04M | Yes (planned) | Form 4 ↗ |
| 2026-04-10 | 2026-04-08 | Tseng Saria, EVP & General Counsel | SSale | −400.00 | $1,292.08 | $517K | Yes (planned) | Form 4 ↗ |
| 2026-04-10 | 2026-04-08 | Tseng Saria, EVP & General Counsel | SSale | −120.00 | $1,287.12 | $154K | Yes (planned) | Form 4 ↗ |
| 2026-04-10 | 2026-04-08 | Tseng Saria, EVP & General Counsel | SSale | −240.00 | $1,279.55 | $307K | Yes (planned) | Form 4 ↗ |
| 2026-04-10 | 2026-04-08 | Tseng Saria, EVP & General Counsel | SSale | −360.00 | $1,270.29 | $457K | Yes (planned) | Form 4 ↗ |
| 2026-04-10 | 2026-04-08 | Tseng Saria, EVP & General Counsel | SSale | −560.00 | $1,266.48 | $709K | Yes (planned) | Form 4 ↗ |
| 2026-04-08 | 2026-04-06 | Tseng Saria EVP & General Counsel | SSale | −1.40K | $1,179.50 | $1.65M | Yes (planned) | Form 4 ↗ |
| 2026-04-08 | 2026-04-06 | Tseng Saria, EVP & General Counsel | SSale | −1.68K | $1,176.35 | $1.98M | Yes (planned) | Form 4 ↗ |
| 2026-04-08 | 2026-04-06 | Tseng Saria, EVP & General Counsel | SSale | −2.04K | $1,170.38 | $2.38M | Yes (planned) | Form 4 ↗ |
| 2026-04-08 | 2026-04-06 | Tseng Saria, EVP & General Counsel | SSale | −684.00 | $1,165.66 | $797K | Yes (planned) | Form 4 ↗ |
| 2026-04-08 | 2026-04-06 | Tseng Saria, EVP & General Counsel | SSale | −560.00 | $1,159.62 | $649K | Yes (planned) | Form 4 ↗ |
| 2026-04-08 | 2026-04-06 | Tseng Saria, EVP & General Counsel | SSale | −480.00 | $1,149.05 | $552K | Yes (planned) | Form 4 ↗ |
| 2026-04-08 | 2026-04-06 | Tseng Saria, EVP & General Counsel | SSale | −556.00 | $1,144.42 | $636K | Yes (planned) | Form 4 ↗ |
| 2026-04-08 | 2026-04-06 | Tseng Saria, EVP & General Counsel | SSale | −244.00 | $1,139.96 | $278K | Yes (planned) | Form 4 ↗ |
| 2026-04-01 | 2026-03-30 | Tseng Saria EVP & General Counsel | SSale | −80.00 | $1,041.12 | $83.3K | Yes (planned) | Form 4 ↗ |
| 2026-04-01 | 2026-03-30 | Tseng Saria, EVP & General Counsel | SSale | −166.00 | $1,035.60 | $172K | Yes (planned) | Form 4 ↗ |
| 2026-04-01 | 2026-03-30 | Tseng Saria, EVP & General Counsel | SSale | −2.44K | $1,029.21 | $2.51M | Yes (planned) | Form 4 ↗ |
| 2026-04-01 | 2026-03-30 | Tseng Saria, EVP & General Counsel | SSale | −2.20K | $1,023.00 | $2.25M | Yes (planned) | Form 4 ↗ |
| 2026-04-01 | 2026-03-30 | Tseng Saria, EVP & General Counsel | SSale | −3.19K | $1,017.22 | $3.25M | Yes (planned) | Form 4 ↗ |
| 2026-04-01 | 2026-03-30 | Tseng Saria, EVP & General Counsel | SSale | −3.36K | $1,009.63 | $3.39M | Yes (planned) | Form 4 ↗ |
| 2026-04-01 | 2026-03-30 | Tseng Saria, EVP & General Counsel | SSale | −9.08K | $1,005.18 | $9.13M | Yes (planned) | Form 4 ↗ |
| 2026-04-01 | 2026-03-30 | Tseng Saria, EVP & General Counsel | SSale | −5.15K | $1,000.81 | $5.16M | Yes (planned) | Form 4 ↗ |
| 2026-03-24 | 2026-03-20 | Sciammas Maurice EVP, WW Sales & Marketing | SSale | −30.00 | $1,095.07 | $32.9K | Yes (planned) | Form 4 ↗ |
| 2026-02-13 | 2026-02-11 | Hsing Michael CEO | SSale | −649.00 | $1,202.28 | $780K | Yes (planned) | Form 4 ↗ |
| 2026-02-13 | 2026-02-11 | Hsing Michael, CEO | SSale | −14.6K | $1,197.20 | $17.5M | Yes (planned) | Form 4 ↗ |
| 2026-02-13 | 2026-02-11 | Hsing Michael, CEO | SSale | −6.08K | $1,192.67 | $7.25M | Yes (planned) | Form 4 ↗ |
| 2026-02-13 | 2026-02-11 | Hsing Michael, CEO | SSale | −2.10K | $1,188.17 | $2.50M | Yes (planned) | Form 4 ↗ |
| 2026-02-13 | 2026-02-11 | Hsing Michael, CEO | SSale | −1.54K | $1,182.82 | $1.82M | Yes (planned) | Form 4 ↗ |
| 2026-02-13 | 2026-02-11 | Hsing Michael, CEO | SSale | −2.80K | $1,177.67 | $3.30M | Yes (planned) | Form 4 ↗ |
| 2026-02-13 | 2026-02-11 | Hsing Michael, CEO | SSale | −1.99K | $1,172.92 | $2.33M | Yes (planned) | Form 4 ↗ |
| 2026-02-13 | 2026-02-11 | Hsing Michael, CEO | SSale | −1.53K | $1,167.62 | $1.79M | Yes (planned) | Form 4 ↗ |
| 2026-02-13 | 2026-02-11 | Hsing Michael, CEO | SSale | −1.37K | $1,163.71 | $1.59M | Yes (planned) | Form 4 ↗ |
| 2026-02-13 | 2026-02-11 | Hsing Michael, CEO | SSale | −363.00 | $1,158.71 | $421K | Yes (planned) | Form 4 ↗ |
| 2026-02-12 | 2026-02-11 | Sciammas Maurice EVP, WW Sales & Marketing | SSale | −200.00 | $1,179.98 | $236K | No | Form 4 ↗ |
| 2026-02-12 | 2026-02-10 | Hsing Michael CEO | SSale | −280.00 | $1,197.26 | $335K | Yes (planned) | Form 4 ↗ |
| 2026-02-12 | 2026-02-10 | Hsing Michael, CEO | SSale | −880.00 | $1,176.04 | $1.03M | Yes (planned) | Form 4 ↗ |
| 2026-02-12 | 2026-02-10 | Hsing Michael, CEO | SSale | −360.00 | $1,161.41 | $418K | Yes (planned) | Form 4 ↗ |
| 2026-02-12 | 2026-02-10 | Hsing Michael, CEO | SSale | −694.00 | $1,154.96 | $802K | Yes (planned) | Form 4 ↗ |
| 2026-02-12 | 2026-02-10 | Hsing Michael, CEO | SSale | −1.22K | $1,151.11 | $1.40M | Yes (planned) | Form 4 ↗ |
| 2026-02-12 | 2026-02-10 | Hsing Michael, CEO | SSale | −3.86K | $1,145.90 | $4.43M | Yes (planned) | Form 4 ↗ |
| 2026-02-12 | 2026-02-10 | Hsing Michael, CEO | SSale | −16.1K | $1,141.88 | $18.4M | Yes (planned) | Form 4 ↗ |
| 2026-02-12 | 2026-02-10 | Hsing Michael, CEO | SSale | −6.33K | $1,136.75 | $7.19M | Yes (planned) | Form 4 ↗ |
| 2026-02-12 | 2026-02-10 | Hsing Michael, CEO | SSale | −4.30K | $1,132.01 | $4.87M | Yes (planned) | Form 4 ↗ |
| 2026-02-11 | 2026-02-09 | Lee Victor K Director | SSale | −400.00 | $1,212.16 | $485K | Yes (planned) | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | Xiao Deming EVP, Global Operations | SSale | −22.9K | $1,171.16 | $26.8M | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | Tseng Saria EVP & General Counsel | SSale | −22.9K | $1,171.16 | $26.8M | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | Sciammas Maurice EVP, WW Sales & Marketing | SSale | −22.9K | $1,171.16 | $26.8M | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | BLEGEN THEODORE EVP and CFO | SSale | −21.7K | $1,171.16 | $25.4M | No | Form 4 ↗ |
| 2026-02-10 | 2026-02-06 | Hsing Michael CEO | SSale | −54.9K | $1,171.16 | $64.3M | No | Form 4 ↗ |
| 2026-02-05 | 2026-02-03 | Wynne Eileen Director | AAward | +189.00 | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-05 | 2026-02-03 | Zhou Jeff Director | AAward | +189.00 | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-05 | 2026-02-03 | CHANG KUO WEI HERBERT Director | AAward | +189.00 | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-05 | 2026-02-03 | Elmiger Eugen J Director | AAward | +189.00 | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-05 | 2026-02-03 | Lee Victor K Director | AAward | +189.00 | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-05 | 2026-02-03 | Martinez Carintia Director | AAward | +189.00 | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-05 | 2026-02-03 | Xiao Deming EVP, Global Operations | AAward | +57.2K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-05 | 2026-02-03 | BLEGEN THEODORE EVP and CFO | AAward | +38.7K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-05 | 2026-02-03 | Tseng Saria EVP & General Counsel | AAward | +57.2K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-05 | 2026-02-03 | Hsing Michael CEO | AAward | +137K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-05 | 2026-02-03 | Sciammas Maurice EVP, WW Sales & Marketing | AAward | +57.2K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE EVP and CFO | SSale | −80.00 | $1,139.49 | $91.2K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −80.00 | $1,137.81 | $91.0K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −120.00 | $1,136.35 | $136K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −120.00 | $1,135.49 | $136K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −241.00 | $1,134.41 | $273K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −379.00 | $1,133.47 | $430K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −322.00 | $1,132.67 | $365K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −198.00 | $1,131.70 | $224K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −320.00 | $1,130.48 | $362K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −240.00 | $1,129.28 | $271K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −240.00 | $1,128.43 | $271K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −80.00 | $1,127.39 | $90.2K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −200.00 | $1,126.58 | $225K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −40.00 | $1,122.56 | $44.9K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −80.00 | $1,120.77 | $89.7K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −40.00 | $1,117.11 | $44.7K | Yes (planned) | Form 4 ↗ |
| 2026-02-04 | 2026-02-02 | BLEGEN THEODORE, EVP and CFO | SSale | −220.00 | $1,110.58 | $244K | Yes (planned) | Form 4 ↗ |
Insiders — a company’s officers, directors and holders of more than 10% of its stock — must report any trade in that stock to the SEC on a Form 4 within two business days. Each row here is one transaction from those filings.
The transaction code tells you what happened: Purchase (P) and Sale (S) are open-market trades — the ones markets watch most; Award (A) is a granted stock or unit, Option exercise (M) converts options into shares, and Gift (G) is a transfer for no consideration. Awards, exercises and gifts are largely compensation or administrative, not a directional bet.
One caveat on sales: many are made under a Rule 10b5-1 plan scheduled months in advance, so a sale is not automatically a bearish signal. Insider activity is a noisy input — read it alongside the filings, not on its own.
See also MPWR’s full analysis or the market-wide insider trading feed. The tabs above jump to MPWR’s other SEC data.
Source: SEC Form 4 filings for MPWR, parsed from EDGAR. Transaction prices are as reported in the filing — SEC public-domain data, not market quotes. Values are shares × reported price where both are disclosed; grants and gifts often carry no price. A delayed record of what insiders reported, not a live position or a recommendation.
Research and education only — not financial advice. TENKis not a registered investment adviser or broker-dealer and gives no personalized advice. Every call is impersonal — identical for all users, generated on a schedule from SEC filings plus a delayed/third-party price feed — may be wrong or out of date, and is not a recommendation to buy or sell any security. The operator and an affiliated trading operation may hold or trade the securities TENK rates; see Disclosures. Past performance does not guarantee future results. Do your own research.