Who owns Monolithic Power (MPWR)?
172 holders named in SEC filings declare between 70.3% and 94.5% of Monolithic Power's shares outstanding, as of Sep 28, 2026. The largest are Vanguard (12.4%), BlackRock (11.4%) and Fidelity (FMR) (10.5%); the five largest hold 43.8% together. Another 1,072 institutions hold small positions worth 5.6%. From Mar 31, 2026 to Jun 30, 2026, institutions that filed both quarters bought 8.9% and sold 10.0% of the shares, a net sale of 1.1%; 190 opened a position, 401 added, 450 reduced and 72 sold out. Biggest buyers: Fidelity (FMR) (+776,427 shares) and VanEck (+221,666 shares). Biggest sellers: T. Rowe Price (-1.0M) and BlackRock (-482,542). Schedule 13D/G filings since Mar 31, 2026: FMR LLC raised its stake to 10.5% on Jun 30, 2026. Directors and officers, from their latest Form 4: Michael Hsing (2.0%), Maurice Sciammas (0.48%) and Deming Xiao (0.47%). Over time, 1,227 managers declared Monolithic Power in their 13F for Q2 2026, against 340 for Q4 2019: together at most 96.9% of the shares outstanding, against 92.5%.
| Holder | Filing | Share of capital | As of | Holding since (13F) |
|---|---|---|---|---|
| Vanguard | 13F | 12.4% | Jun 30, 2026 | Q4 2019 or earlier |
| BlackRock | 13F | 11.4% | Jun 30, 2026 | Q4 2019 or earlier |
| Fidelity (FMR) | 13F | 10.5% | Jun 30, 2026 | Q4 2019 or earlier |
| Invesco | 13F | 4.8% | Jun 30, 2026 | Q4 2019 or earlier |
| State Street | 13F | 4.6% | Jun 30, 2026 | Q4 2019 or earlier |
| Geode Capital | 13F | 2.4% | Jun 30, 2026 | Q4 2019 or earlier |
| T. Rowe Price | 13F | 2.0% | Jun 30, 2026 | Q4 2019 or earlier |
| Michael Hsing | Form 4 | 2.0% | Sep 28, 2026 | — |
| Franklin Templeton | 13F | 1.7% | Jun 30, 2026 | Q4 2019 or earlier |
| Goldman Sachs | 13F | 1.6% | Jun 30, 2026 | Q4 2019 or earlier |
| Norges Bank | 13F | 1.5% | Jun 30, 2026 | Q4 2019 or earlier |
| VanEck | 13F | 1.5% | Jun 30, 2026 | Q4 2020 |
| UBS | 13F | 1.5% | Jun 30, 2026 | Q4 2019 or earlier |
| Morgan Stanley | 13F | 1.5% | Jun 30, 2026 | Q4 2019 or earlier |
| Bank of America | 13F | 1.1% | Jun 30, 2026 | Q4 2019 or earlier |
| ROYAL BANK OF CANADA | 13F | 0.99% | Jun 30, 2026 | Q4 2019 or earlier |
| FIRST TRUST ADVISORS LP | 13F | 0.98% | Jun 30, 2026 | Q4 2019 or earlier |
| Northern Trust | 13F | 0.98% | Jun 30, 2026 | Q4 2019 or earlier |
| Barclays | 13F | 0.96% | Jun 30, 2026 | Q4 2019 or earlier |
| Rafferty Asset Management, LLC | 13F | 0.93% | Jun 30, 2026 | Q4 2019 or earlier |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ | 13F | 0.90% | Jun 30, 2026 | Q4 2019 or earlier |
| JPMorgan | 13F | 0.89% | Jun 30, 2026 | Q4 2019 or earlier |
| Charles Schwab | 13F | 0.79% | Jun 30, 2026 | Q4 2019 or earlier |
| Legal & General | 13F | 0.73% | Jun 30, 2026 | Q4 2019 or earlier |
| VOYA INVESTMENT MANAGEMENT LLC | 13F | 0.69% | Jun 30, 2026 | Q4 2019 or earlier |
Monolithic Power institutional ownership over time
| Quarter | 13F managers | Share of the company (upper bound) | Value declared | Held by stock pickers |
|---|---|---|---|---|
| Q4 2019 | 340 | 92.5% | $7.4B | 62.3% |
| Q4 2020 | 494 | 93.8% | $15.5B | 58.3% |
| Q4 2021 | 603 | 93.9% | $21.4B | 57.5% |
| Q4 2022 | 599 | 99.7% | $16.6B | 58.3% |
| Q4 2023 | 727 | 94.7% | $28.6B | 56.1% |
| Q4 2024 | 850 | 95.3% | $27.5B | 51.2% |
| Q4 2025 | 1,050 | 101.7% | $44.2B | 47.4% |
| Q2 2026 | 1,227 | 96.9% | $65.6B | 46.2% |
From SEC Form 13F, every quarter since the end of 2019, read like the current quarter: entities of a house summed, a value contradicting its share count set aside. The share of the company is an upper bound — two managers can declare the same shares — over the shares outstanding at that date.