MONOLITHIC PWR SYS INC (MPWR)
Institutional ownership reported to the SEC as of Q2 2026, across 32 quarters.
Institutions report 47,664,312 shares against 49,143,000 outstanding. Shares only - option lines are excluded, which is why this can be compared with the company at all. The count comes from the cover page of the company's own most recent report, so it is dated when that was filed rather than at quarter end. A figure this high can overstate: where an adviser and a sub-adviser both report the same shares, both are counted.
Calls and puts are the parts of reported value carried in derivative lines rather than shares, and they point in opposite directions: a manager holding calls is positioned for the security, one holding puts against it - or hedging shares they already own, which is why index funds carry so many. Most sites add the two together and report one figure, which averages away the only interesting part.
Holders
| Filer | Value | Shares | Their book | Held | Change |
|---|---|---|---|---|---|
| BlackRock, Inc. | $7.7B | 5,589,925 | 0.11% | 8q | -7.9%-$667.0M |
| FMR LLC | $7.2B | 5,177,258 | 0.31% | 31q | +17.6%+$1.1B |
| VANGUARD CAPITAL MANAGEMENT LLC | $4.3B | 3,126,756 | 0.09% | 2q | +1.4%+$59.9M |
| VANGUARD PORTFOLIO MANAGEMENT LLC | $3.5B | 2,504,858 | 0.16% | 2q | HELD |
| Invesco Ltd. | $3.2B | 2,343,930 | 0.26% | 31q | -6.8%-$237.8M |
| STATE STREET CORP | $3.2B | 2,282,186 | 0.09% | 31q | +4.3%+$129.8M |
| GEODE CAPITAL MANAGEMENT, LLC | $1.6B | 1,195,281 | 0.09% | 31q | -16.5%-$326.3M |
| PRICE T ROWE ASSOCIATES INC /MD/ | $1.4B | 976,798 | 0.14% | 31q | -22.7%-$395.6M |
| FRANKLIN RESOURCES INC | $1.1B | 811,974 | 0.24% | 31q | -12.6%-$161.3M |
| GOLDMAN SACHS GROUP INC | $1.1B incl. $14.7M options PUT | 780,650 | 0.09% | 31q | +37.4%+$297.9M |
| NORGES BANK | $1.0B | 751,399 | 0.10% | 32q | +3.4%+$34.1M |
| VAN ECK ASSOCIATES CORP | $1.0B | 746,237 | 0.63% | 23q | +42.3%+$306.4M |
| MORGAN STANLEY | $1.0B | 727,885 | 0.05% | 35q | +10.9%+$98.9M |
| BANK OF AMERICA CORP /DE/ | $741.3M | 536,236 | 0.05% | 31q | +40.3%+$213.0M |
| ROYAL BANK OF CANADA | $673.5M | 487,212 | 0.10% | 31q | +2.9%+$19.1M |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | $673.3M incl. $502.2M options CALL+PUT | 123,776 | 0.05% | 31q | +313.1%+$510.3M |
| FIRST TRUST ADVISORS LP | $667.4M | 482,781 | 0.39% | 31q | -18.4%-$150.1M |
| NORTHERN TRUST CORP | $662.8M | 479,492 | 0.08% | 31q | -2.0%-$13.3M |
| BARCLAYS PLC | $655.4M | 474,132 | 0.13% | 31q | -14.7%-$112.9M |
| Rafferty Asset Management, LLC | $634.9M | 459,278 | 1.45% | 31q | +44.7%+$196.0M |
| UBS Group AG | $622.7M incl. $1.4M options CALL | 449,479 | 0.08% | 31q | -16.8%-$126.0M |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ | $611.2M | 442,176 | 0.19% | 31q | -22.1%-$173.6M |
| JANE STREET GROUP, LLC | $582.5M incl. $334.7M options CALL+PUT | 179,293 | 0.05% | 30q | +3427.3%+$566.0M |
| JPMORGAN CHASE & CO | $571.0M | 434,949 | 0.03% | 31q | -21.6%-$157.5M |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | $537.7M | 388,951 | 0.07% | 31q | +3.3%+$17.4M |
| Legal & General Group Plc | $497.6M | 359,936 | 0.10% | 31q | -5.3%-$27.9M |
| VOYA INVESTMENT MANAGEMENT LLC | $469.7M | 340,269 | 0.41% | 31q | -13.5%-$73.6M |
| CITIGROUP INC | $449.7M | 325,281 | 0.15% | 31q | -4.6%-$21.5M |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC | $404.2M | 292,368 | 0.07% | 31q | -3.3%-$13.6M |
| Bank of New York Mellon Corp | $402.4M | 291,107 | 0.07% | 31q | HELD |
| VANGUARD FIDUCIARY TRUST CO | $387.0M | 279,965 | 0.09% | 2q | +0.5%+$2.0M |
| BNP PARIBAS FINANCIAL MARKETS | $310.6M incl. $23.2M options CALL+PUT | 207,881 | 0.11% | 31q | -7.2%-$24.1M |
| FIL Ltd | $310.5M | 224,582 | 0.22% | 8q | +45.2%+$96.7M |
| California Public Employees Retirement System | $309.5M | 223,899 | 0.17% | 31q | +40.2%+$88.8M |
| CITADEL ADVISORS LLC | $305.5M incl. $217.7M options CALL+PUT | 63,487 | 0.03% | 31q | +369.9%+$240.5M |
| KAYNE ANDERSON RUDNICK INVESTMENT MANAGEMENT LLC | $284.9M | 206,130 | 0.89% | 15q | -22.7%-$83.7M |
| TWO SIGMA INVESTMENTS, LP | $270.8M incl. $7.5M options CALL+PUT | 190,505 | 0.20% | 3q | +1485.2%+$253.7M |
| HSBC HOLDINGS PLC | $262.4M | 190,811 | 0.11% | 31q | +20.1%+$43.9M |
| JENNISON ASSOCIATES LLC | $256.4M | 185,502 | 0.15% | 14q | +275.6%+$188.2M |
| BROWN ADVISORY INC | $249.5M | 180,434 | 0.39% | 31q | -52.5%-$275.8M |
| PRINCIPAL FINANCIAL GROUP INC | $249.2M | 180,241 | 0.12% | 31q | +3.5%+$8.4M |
| MILLENNIUM MANAGEMENT LLC | $240.2M incl. $51.0M options CALL+PUT | 136,835 | 0.09% | 31q | HELD |
| DEUTSCHE BANK AG\ | $231.3M | 167,290 | 0.07% | 34q | -7.9%-$20.0M |
| SG Americas Securities, LLC | $224.9M incl. $312.0K options CALL | 162,475 | 0.13% | 31q | -10.6%-$26.7M |
| NEUBERGER BERMAN GROUP LLC | $216.1M | 156,360 | 0.14% | 31q | +4.2%+$8.6M |
| DIMENSIONAL FUND ADVISORS LP | $213.4M | 154,447 | 0.04% | 31q | HELD |
| CANADA PENSION PLAN INVESTMENT BOARD | $205.7M | 148,792 | 0.11% | 11q | +178.9%+$131.9M |
| EARNEST PARTNERS LLC | $205.6M | 148,707 | 0.74% | 31q | -2.0%-$4.2M |
| SEI INVESTMENTS CO | $204.5M | 147,966 | 0.18% | 31q | -4.7%-$10.1M |
| AMERICAN CENTURY COMPANIES INC | $203.5M | 147,212 | 0.09% | 31q | -26.3%-$72.5M |
| Amundi | $201.4M | 145,747 | 0.05% | 21q | -8.3%-$18.2M |
| RAYMOND JAMES FINANCIAL INC | $201.3M | 145,618 | 0.05% | 7q | -25.7%-$69.7M |
| VAUGHAN NELSON INVESTMENT MANAGEMENT, L.P. | $200.4M | 144,974 | 1.77% | 20q | +4.0%+$7.8M |
| FEDERATED HERMES, INC. | $200.4M | 144,949 | 0.29% | 31q | +198.5%+$133.2M |
| ALLIANCEBERNSTEIN L.P. | $193.6M | 177,107 | 0.06% | 31q | +42.1%+$57.4M |
| DekaBank Deutsche Girozentrale | $190.2M | 190,443 | 0.32% | 31q | HELD |
| Mitsubishi UFJ Asset Management Co., Ltd. | $182.6M | 132,064 | 0.10% | 23q | HELD |
| Swiss National Bank | $181.9M | 131,610 | 0.10% | 31q | -6.4%-$12.3M |
| WELLS FARGO & COMPANY/MN | $181.5M | 131,302 | 0.03% | 31q | +29.1%+$40.9M |
| Artisan Partners Limited Partnership | $179.9M | 130,154 | 0.29% | 31q | -13.7%-$28.6M |
| AMERIPRISE FINANCIAL INC | $179.3M | 129,720 | 0.04% | 31q | +8.6%+$14.2M |
| Nuveen, LLC | $178.7M | 129,292 | 0.04% | 6q | -17.0%-$36.7M |
| Allianz Asset Management GmbH | $161.2M incl. $414.7K options PUT | 116,281 | 0.13% | 40q | +20.5%+$27.5M |
| TimesSquare Capital Management, LLC | $153.2M | 110,824 | 2.25% | 31q | -20.2%-$38.7M |
| Sumitomo Mitsui Trust Group, Inc. | $153.2M | 110,819 | 0.09% | 23q | -3.2%-$5.0M |
| ENVESTNET ASSET MANAGEMENT INC | $150.1M | 108,573 | 0.04% | 31q | -13.7%-$23.9M |
| Vanguard Global Advisers, LLC | $146.7M | 106,109 | 0.07% | 2q | HELD |
| NATIXIS ADVISORS, LLC | $146.2M | 105,784 | 0.16% | 31q | +10.4%+$13.7M |
| NOMURA ASSET MANAGEMENT INTERNATIONAL INC. | $143.1M | 103,548 | 0.21% | 3q | -30.0%-$61.4M |
| Pictet Asset Management Holding SA | $139.2M | 100,736 | 0.13% | 12q | -16.7%-$27.8M |
| Mirae Asset Global Investments Co., Ltd. | $134.9M | 97,618 | 0.20% | 23q | +17.2%+$19.8M |
| ADAGE CAPITAL PARTNERS GP, L.L.C. | $133.2M | 96,352 | 0.19% | 22q | +30.8%+$31.4M |
| Robeco Schweiz AG | $132.8M | 96,033 | 2.13% | 31q | +1.1%+$1.4M |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. | $131.4M | 95,039 | 0.13% | 15q | -26.9%-$48.3M |
| VICTORY CAPITAL MANAGEMENT INC | $130.6M | 94,482 | 0.07% | 31q | -15.6%-$24.2M |
| LORD, ABBETT & CO. LLC | $130.6M | 94,447 | 0.37% | 4q | -22.5%-$37.9M |
| RHUMBLINE ADVISERS | $130.4M | 94,367 | 0.10% | 31q | -7.6%-$10.7M |
| VANGUARD ASSET MANAGEMENT, Ltd | $128.0M | 92,594 | 0.09% | 2q | +13.1%+$14.9M |
| HRT FINANCIAL LP | $127.4M incl. $20.5M options OPT | 92,149 | 0.23% | new | NEW |
| IMC-Chicago, LLC | $126.4M incl. $112.9M options CALL+PUT | 9,733 | 0.03% | 10q | +210.9%+$85.7M |
| Thrivent Financial for Lutherans | $124.5M | 90,064 | 0.21% | 31q | -6.3%-$8.4M |
| D1 Capital Partners L.P. | $117.6M | 85,103 | 0.34% | new | NEW |
| Baird Financial Group, Inc. | $113.2M | 81,895 | 0.16% | 31q | +10.3%+$10.5M |
| Allspring Global Investments Holdings, LLC | $112.3M | 84,341 | 0.17% | 19q | -29.0%-$45.9M |
| CONGRESS ASSET MANAGEMENT CO | $111.2M | 80,425 | 0.68% | 31q | -3.5%-$4.0M |
| ZEVENBERGEN CAPITAL INVESTMENTS LLC | $108.7M | 78,604 | 2.48% | 31q | -4.0%-$4.6M |
| CAPITOLIS LIQUID GLOBAL MARKETS LLC | $108.4M | 78,432 | 0.47% | 2q | +1686.2%+$102.4M |
| HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND | $105.6M | 76,360 | 0.15% | 12q | -43.8%-$82.4M |
| Liontrust Investment Partners LLP | $104.8M | 75,786 | 1.54% | 7q | +6.3%+$6.2M |
| Quantinno Capital Management LP | $104.6M | 75,694 | 0.13% | 15q | +4.0%+$4.0M |
| Tidal Investments LLC | $101.3M incl. $29.6M options CALL+PUT | 51,894 | 0.18% | 21q | +46.7%+$32.2M |
| DF DENT & CO INC | $100.8M | 72,954 | 1.91% | 16q | -17.6%-$21.6M |
| WELLINGTON MANAGEMENT GROUP LLP | $99.5M | 72,001 | 0.02% | 31q | -71.3%-$246.8M |
| Ensign Peak Advisors, Inc | $98.4M | 71,154 | 0.16% | 27q | -8.9%-$9.6M |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM | $96.0M | 69,420 | 0.09% | 31q | -4.1%-$4.1M |
| STIFEL FINANCIAL CORP | $92.8M | 67,103 | 0.08% | 31q | -15.4%-$16.9M |
| Qube Research & Technologies Ltd | $91.4M incl. $2.2M options CALL+PUT | 64,548 | 0.08% | 17q | HELD |
| LPL Financial LLC | $90.2M | 65,267 | 0.02% | 31q | -3.9%-$3.7M |
| ProShare Advisors LLC | $89.3M | 64,600 | 0.13% | 31q | -20.7%-$23.3M |
| Squarepoint Ops LLC | $88.1M incl. $14.8M options CALL+PUT | 53,024 | 0.10% | 23q | +63.6%+$34.2M |
Showing the largest 100 of 1,263 reported holders. The count of 1,262 above leaves out 1 position whose reported value failed our price check; it is listed here as filed.
What the company announced
Form 8-K filings from the last 120 days, showing only the items worth a reader's attention. Earnings releases, exhibit attachments and general disclosures are filed constantly and are left out. Filed is when the SEC received it; event is the date the company says the thing happened.
| Filed | Event date | What | Source |
|---|---|---|---|
| 2026-10-29 | 2026-10-27 | Directors or officers departed or appointed | filing |
What the insiders did
Open market purchases and sales reported on Form 4 in the last 180 days. Grants, option exercises and shares surrendered to cover tax are left out: they are compensation rather than a decision to buy or sell. Where a broker filled one order in tranches the lines are summed, because it was one decision.
Officers and directors
| Date | Insider | Role | Side | Shares | Value |
|---|---|---|---|---|---|
| 2026-05-18 | Hsing Michael | CEO | Sold | 40,000 | $59.3M ×13 |
| 2026-09-28 | Hsing Michael | CEO | Sold | 30,000 | $40.3M ×8 |
| 2026-07-15 | Sciammas Maurice | EVP, WW Sales & Marketing | Sold | 15,000 | $20.2M ×18 |
| 2026-05-15 | Sciammas Maurice | EVP, WW Sales & Marketing | Sold | 12,000 | $18.7M ×8 |
| 2026-05-27 | Tseng Saria | EVP & General Counsel | Sold | 7,565 | $12.9M |
| 2026-05-22 | Tseng Saria | EVP & General Counsel | Sold | 5,000 | $7.9M |
| 2026-05-26 | Zhou Jeff | Director | Sold | 486 | $816.5K |
| 2026-08-05 | DEAN ROBERT W II | Interim CFO | Sold | 105 | $141.1K |
Quarter by quarter
Coverage begins with the quarter ending 2018-12-31. Earlier filings exist only as occasional late amendments, too sparse to describe a market, so they are not shown.
| Quarter | Holders | Value | Shares | New | Added | Trimmed | Options |
|---|---|---|---|---|---|---|---|
| Q3 2026 | 419 | $2.2B | 1,651,832 | 45 | 141 | 148 | 0.0% |
| Q2 2026 | 1,262 | $67.2B | 47,664,312 | 207 | 407 | 445 | 2.3% |
| Q1 2026 | 1,141 | $52.3B | 47,274,032 | 169 | 372 | 402 | 1.4% |
| Q4 2025 | 1,072 | $45.6B | 49,382,408 | 136 | 367 | 339 | 1.8% |
| Q3 2025 | 989 | $44.6B | 47,721,718 | 159 | 336 | 309 | 1.9% |
| Q2 2025 | 920 | $35.3B | 47,541,985 | 127 | 363 | 290 | 1.6% |
| Q1 2025 | 870 | $27.7B | 46,838,698 | 118 | 316 | 302 | 1.9% |
| Q4 2024 | 876 | $28.5B | 46,556,807 | 94 | 312 | 283 | 3.3% |
| Q3 2024 | 895 | $44.2B | 47,280,977 | 117 | 314 | 307 | 1.2% |
| Q2 2024 | 846 | $40.2B | 48,275,900 | 113 | 309 | 256 | 1.4% |
| Q1 2024 | 817 | $33.3B | 48,139,589 | 125 | 285 | 260 | 2.3% |
| Q4 2023 | 744 | $30.7B | 47,209,097 | 100 | 259 | 226 | 3.0% |
| Q3 2023 | 659 | $21.9B | 46,091,237 | 64 | 249 | 231 | 2.8% |
| Q2 2023 | 657 | $25.7B | 46,962,541 | 70 | 223 | 248 | 1.4% |
| Q1 2023 | 672 | $24.7B | 49,628,471 | 125 | 223 | 219 | 0.8% |
| Q4 2022 | 612 | $16.7B | 46,897,481 | 64 | 209 | 240 | 0.7% |
| Q3 2022 | 619 | $24.7B | 67,619,279 | 74 | 236 | 218 | 0.6% |
| Q2 2022 | 614 | $25.4B | 65,639,561 | 72 | 238 | 213 | 0.9% |
| Q1 2022 | 604 | $35.9B | 73,565,702 | 74 | 241 | 192 | 0.6% |
| Q4 2021 | 616 | $37.0B | 74,740,184 | 75 | 220 | 196 | 0.4% |
| Q3 2021 | 573 | $46.6B | 95,797,671 | 79 | 166 | 209 | 0.5% |
| Q2 2021 | 533 | $34.0B | 90,549,074 | 60 | 192 | 175 | 0.5% |
| Q1 2021 | 518 | $31.3B | 88,259,737 | 73 | 192 | 191 | 0.5% |
| Q4 2020 | 502 | $31.6B | 85,817,054 | 97 | 160 | 159 | 0.4% |
| Q3 2020 | 435 | $23.7B | 84,642,684 | 66 | 144 | 162 | 0.2% |
| Q2 2020 | 400 | $19.3B | 81,008,931 | 79 | 138 | 131 | 0.2% |
| Q1 2020 | 349 | $17.9B | 106,744,007 | 41 | 121 | 128 | 0.1% |
| Q4 2019 | 351 | $23.6B | 132,496,975 | 41 | 133 | 110 | 0.1% |
| Q3 2019 | 348 | $20.9B | 133,900,881 | 39 | 116 | 121 | 0.1% |
| Q2 2019 | 344 | $19.8B | 145,194,230 | 43 | 123 | 122 | 0.3% |
| Q1 2019 | 346 | $17.4B | 128,482,254 | 45 | 134 | 121 | 0.2% |
| Q4 2018 | 335 | $14.8B | 126,894,834 | 3 | 6 | 7 | 0.2% |
