The Filings Report

Monolithic Power Systems insider trading

MPWRfinancial statementsForm 4 filings on EDGAR463 transactions since Nov 1, 2024

From August 4, 2026 to November 1, 2026, 0 insiders at Monolithic Power Systems bought $0 of stock in the open market, and 3 sold $41M. Officers and directors accounted for $0 of purchases and $41M of sales. The last reported transaction was an open-market sale by Hsing Michael on September 28, 2026.

The answer card and chart use the same period. Change the range above the chart to update both. Form 4 filings through September 30, 2026; awards, option exercises, tax withholding and gifts are excluded from these totals.

Stock price and insider activity

Daily price candles with insider purchases and sales directly beneath them on the same timeline. Bars show individual days; totals sum all days in the selected period.

MPWR daily priceSplit-adjusted prices in US dollars

Bought $0Sold $41MAug 4, 2026 – Nov 1, 2026

Oct 30, 2026O $1174.00 · H $1263.05 · L $1171.02 · C $1211.63Bought $0 (0)Sold $0 (0)
$1105$1207$1309$1411$15142026-08-04: open $1402.10, high $1425.99, low $1333.32, close $1335.032026-08-05: open $1320.01, high $1358.61, low $1309.26, close $1345.462026-08-06: open $1313.25, high $1415.37, low $1305.13, close $1359.082026-08-07: open $1385.97, high $1417.09, low $1370.95, close $1401.542026-08-10: open $1428.22, high $1430.00, low $1379.17, close $1381.102026-08-11: open $1413.78, high $1431.63, low $1383.63, close $1402.112026-08-12: open $1451.18, high $1464.99, low $1423.10, close $1425.012026-08-13: open $1421.44, high $1438.38, low $1358.00, close $1362.552026-08-14: open $1360.00, high $1404.14, low $1355.11, close $1402.012026-08-17: open $1418.01, high $1448.76, low $1411.60, close $1415.992026-08-18: open $1365.45, high $1376.53, low $1303.22, close $1333.182026-08-19: open $1321.12, high $1335.19, low $1267.77, close $1300.142026-08-20: open $1311.34, high $1327.00, low $1295.02, close $1310.602026-08-21: open $1321.13, high $1337.70, low $1297.30, close $1316.282026-08-24: open $1298.38, high $1305.64, low $1255.56, close $1285.032026-08-25: open $1310.06, high $1322.99, low $1291.54, close $1304.152026-08-26: open $1301.04, high $1311.02, low $1284.56, close $1303.882026-08-27: open $1319.75, high $1332.00, low $1290.86, close $1311.082026-08-28: open $1306.03, high $1306.03, low $1254.01, close $1256.262026-08-31: open $1261.90, high $1279.00, low $1253.00, close $1267.772026-09-01: open $1245.11, high $1250.00, low $1211.86, close $1225.962026-09-02: open $1224.92, high $1245.23, low $1211.74, close $1219.362026-09-03: open $1200.70, high $1225.00, low $1189.49, close $1213.652026-09-04: open $1239.13, high $1239.13, low $1206.55, close $1223.862026-09-08: open $1230.64, high $1243.09, low $1211.22, close $1218.502026-09-09: open $1206.70, high $1228.82, low $1198.17, close $1203.752026-09-10: open $1184.85, high $1205.20, low $1175.95, close $1186.082026-09-11: open $1200.80, high $1241.04, low $1194.47, close $1234.462026-09-14: open $1184.43, high $1185.89, low $1141.38, close $1143.242026-09-15: open $1164.97, high $1171.18, low $1136.65, close $1142.462026-09-16: open $1157.42, high $1176.05, low $1133.83, close $1147.612026-09-17: open $1183.15, high $1184.15, low $1146.40, close $1169.582026-09-18: open $1185.52, high $1221.51, low $1176.21, close $1217.802026-09-21: open $1243.25, high $1283.83, low $1217.24, close $1277.682026-09-22: open $1278.08, high $1387.46, low $1271.03, close $1380.622026-09-23: open $1367.08, high $1371.66, low $1302.10, close $1355.472026-09-24: open $1317.09, high $1349.64, low $1313.09, close $1335.552026-09-25: open $1332.63, high $1377.14, low $1329.47, close $1367.432026-09-28: open $1353.13, high $1359.76, low $1320.80, close $1351.202026-09-29: open $1372.05, high $1374.32, low $1347.85, close $1355.992026-09-30: open $1353.77, high $1361.44, low $1324.96, close $1347.222026-10-01: open $1359.98, high $1368.67, low $1331.00, close $1359.722026-10-02: open $1406.00, high $1455.99, low $1393.13, close $1439.732026-10-05: open $1444.41, high $1482.97, low $1432.38, close $1479.892026-10-06: open $1487.88, high $1491.64, low $1458.79, close $1473.692026-10-07: open $1447.64, high $1450.71, low $1412.68, close $1425.982026-10-08: open $1405.99, high $1416.62, low $1349.39, close $1369.802026-10-09: open $1396.53, high $1401.76, low $1351.26, close $1386.292026-10-12: open $1365.36, high $1365.36, low $1314.52, close $1319.232026-10-13: open $1294.29, high $1322.40, low $1283.81, close $1319.552026-10-14: open $1295.00, high $1300.76, low $1234.36, close $1243.112026-10-15: open $1198.15, high $1260.24, low $1195.00, close $1249.202026-10-16: open $1223.32, high $1249.00, low $1207.20, close $1210.862026-10-19: open $1255.41, high $1283.59, low $1236.26, close $1253.662026-10-20: open $1232.85, high $1284.87, low $1222.29, close $1248.742026-10-21: open $1265.58, high $1288.27, low $1259.87, close $1283.322026-10-22: open $1227.18, high $1230.42, low $1147.17, close $1167.932026-10-23: open $1156.39, high $1169.06, low $1126.57, close $1140.122026-10-26: open $1141.84, high $1178.38, low $1135.18, close $1167.272026-10-27: open $1183.43, high $1220.77, low $1173.95, close $1211.892026-10-28: open $1224.14, high $1224.14, low $1188.93, close $1211.222026-10-29: open $1199.16, high $1209.86, low $1163.86, close $1198.812026-10-30: open $1174.00, high $1263.05, low $1171.02, close $1211.63Insider purchases / sales · USD$50M$0−$50M2026-08-05: 0 purchases ($0), 1 sales ($141K)2026-08-11: 0 purchases ($0), 1 sales ($71K)2026-08-17: 0 purchases ($0), 1 sales ($8K)2026-08-24: 0 purchases ($0), 2 sales ($106K)2026-09-28: 0 purchases ($0), 8 sales ($40M)Aug 4Aug 26Sep 17Oct 9Oct 30

purchases above zero; sales below. Both use the transaction date and the same dollar scale. Hover, tap, or use arrow keys to inspect a date. Awards, exercises, tax withholding and gifts are excluded.

Dates with prices or insider activity are spaced evenly; empty weekends and holidays are omitted. Prices through Oct 30, 2026. Insider data through Nov 1, 2026. Prices are adjusted for splits; transaction values are reported dollars.

Every transaction

463 transactions from November 1, 2024 to November 1, 2026, newest first. Open-market purchases and sales are coloured; awards, exercises, tax withholding and gifts are grey and not counted.

TradedInsiderRoleTransactionSharesPriceValueHeld afterFiled
Sep 28, 2026Hsing MichaelCEO, Directoropen-market sale10b5-1596$1323.31$789K847,668Sep 30, 2026
Sep 28, 2026Hsing MichaelCEO, Directoropen-market sale10b5-12,121$1328.54$3M845,547Sep 30, 2026
Sep 28, 2026Hsing MichaelCEO, Directoropen-market sale10b5-11,111$1333.34$1M844,436Sep 30, 2026
Sep 28, 2026Hsing MichaelCEO, Directoropen-market sale10b5-12,949$1338.66$4M841,487Sep 30, 2026
Sep 28, 2026Hsing MichaelCEO, Directoropen-market sale10b5-15,783$1343.76$8M835,704Sep 30, 2026
Sep 28, 2026Hsing MichaelCEO, Directoropen-market sale10b5-16,343$1347.15$9M829,361Sep 30, 2026
Sep 28, 2026Hsing MichaelCEO, Directoropen-market sale10b5-110,967$1351.43$15M818,394Sep 30, 2026
Sep 28, 2026Hsing MichaelCEO, Directoropen-market sale10b5-1130$1356.94$176K818,264Sep 30, 2026
Aug 31, 2026Tseng SariaEVP & General Counselgift2,000$0.00—142,218Sep 2, 2026
Aug 31, 2026Tseng SariaEVP & General Counselgiftindirect2,000$0.00—2,000Sep 2, 2026
Aug 24, 2026Dean Robert W IIInterim CFOopen-market sale32$1297.72$42K7,094Aug 26, 2026
Aug 24, 2026Dean Robert W IIInterim CFOother5$0.00—7,089Aug 26, 2026
Aug 24, 2026Chang Kuo Wei HerbertDirectoropen-market sale50$1281.57$64K515Aug 25, 2026
Aug 17, 2026Dean Robert W IIInterim CFOopen-market sale6$1413.64$8K7,126Aug 19, 2026
Aug 11, 2026Chang Kuo Wei HerbertDirectoropen-market sale50$1420.00$71K565Aug 13, 2026
Aug 5, 2026Dean Robert W IIInterim CFOopen-market sale105$1344.27$141K7,132Aug 6, 2026
Aug 4, 2026Sciammas MauriceEVP, WW Sales & Marketinggift25,000$0.00—126,644Aug 6, 2026
Aug 4, 2026Sciammas MauriceEVP, WW Sales & Marketinggiftindirect25,000$0.00—36,062Aug 6, 2026
Aug 3, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1indirect30$1343.94$40K1,119Aug 5, 2026
Jul 25, 2026Dean Robert W IIInterim CFOaward1,359$0.00—7,237Jul 28, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1527$1314.03$692K166,117Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1274$1318.42$361K165,843Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1409$1323.93$541K165,434Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1464$1329.30$617K164,970Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1776$1334.59$1M164,194Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-11,460$1339.59$2M162,734Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-11,864$1344.16$3M160,870Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-11,506$1348.91$2M159,364Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-15,640$1352.95$8M153,724Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-150$1359.36$68K153,674Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1240$1369.18$329K153,434Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1472$1375.47$649K152,962Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1418$1378.73$576K152,544Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1410$1384.11$567K152,134Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-150$1388.19$69K152,084Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1213$1396.16$297K151,871Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1117$1400.45$164K151,754Jul 17, 2026
Jul 15, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1110$1405.71$155K151,644Jul 17, 2026
Jul 1, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1indirect30$1351.61$41K1,149Jul 6, 2026
Jun 1, 2026Sciammas MauriceEVP, WW Sales & Marketingopen-market sale10b5-1indirect30$1533.95$46K1,179Jun 3, 2026
May 29, 2026Sciammas MauriceEVP, WW Sales & Marketinggiftindirect12,472$0.00—12,625Jun 2, 2026
May 27, 2026Tseng SariaEVP & General Counselopen-market sale7,565$1700.00$13M144,218May 29, 2026
May 26, 2026Dean Robert W IIInterim CFOopen-market sale22$1649.56$36K5,878May 28, 2026
May 26, 2026Zhou JeffDirectoropen-market sale486$1680.00$816K3,800May 27, 2026
May 22, 2026Tseng SariaEVP & General Counselgift200$0.00—156,783May 27, 2026
May 22, 2026Tseng SariaEVP & General Counselopen-market sale5,000$1586.43$8M151,783May 27, 2026
May 18, 2026Hsing MichaelCEO, Directoropen-market sale3,424$1462.61$5M884,839May 20, 2026
May 18, 2026Hsing MichaelCEO, Directoropen-market sale5,819$1467.62$9M879,020May 20, 2026
May 18, 2026Hsing MichaelCEO, Directoropen-market sale5,049$1472.84$7M873,971May 20, 2026
May 18, 2026Hsing MichaelCEO, Directoropen-market sale4,082$1476.96$6M869,889May 20, 2026

Who the insiders are

Everyone who reported a transaction since November 1, 2024, by open-market value over twelve months. Shares held are after the insider’s latest directly held transaction.

InsiderRoleLast transactionKindShares heldBought, 12 monthsSold, 12 monthsSales under a plan
Hsing MichaelCEO, DirectorSep 28, 2026open-market sale847,668—$355M (89)39 of 89
Tseng SariaEVP & General CounselAug 31, 2026gift142,218—$132M (62)31 of 62
Sciammas MauriceEVP, WW Sales & MarketingAug 4, 2026gift126,644—$101M (61)32 of 61
Xiao DemingEVP, Global OperationsMay 6, 2026open-market sale232,630—$76M (5)0 of 5
Blegen TheodoreEVP and CFOFeb 6, 2026open-market sale82,353—$37M (65)64 of 65
Elmiger Eugen JDirectorMay 6, 2026open-market sale17,082—$19M (9)0 of 9
Zhou JeffDirectorMay 26, 2026open-market sale3,800—$3M (4)0 of 4
Lee Victor KDirectorFeb 9, 2026open-market sale27,756—$2M (8)8 of 8
Wynne EileenDirectorMay 6, 2026open-market sale1,007—$530K (1)0 of 1
Chang Kuo Wei HerbertDirectorAug 24, 2026open-market sale515—$312K (4)0 of 4
Dean Robert W IIInterim CFOAug 24, 2026open-market sale7,094—$234K (5)0 of 5
Martinez CarintiaDirectorFeb 3, 2026award1,067———

Questions

Are Monolithic Power Systems insiders buying or selling?

Over the twelve months to November 1, 2026, 11 insiders at Monolithic Power Systems sold $728M of stock in the open market, all by officers and directors, and no insider bought. Net, insiders sold $728M. Only open-market purchases and sales are counted.

Who sold the most Monolithic Power Systems stock in the last year?

Hsing Michael (CEO, Director) sold $355M in 89 open-market sales over the twelve months to November 1, 2026.

Do Monolithic Power Systems executives sell under 10b5-1 plans?

174 of the 313 open-market sales in the last twelve months (56%) were reported as made under a Rule 10b5-1 trading plan, set up in advance. A sale under a plan is still counted as a sale.

What counts as insider buying here?

Only open-market purchases (Form 4 code P) and sales (code S) by officers, directors and 10% owners. Stock awards, option exercises, shares withheld for tax and gifts are listed in the table but never counted as buying or selling.

More on Monolithic Power Systems

From Form 4, 4/A and 5 filings with the SEC. A record of insider transactions, not a recommendation.