Masimo Corp
MASIDelisted Jun 10, 2026- Industry
- Electromedical & Electrotherapeutic Apparatus
- SEC CIK
- 0000937556
Masimo Corp was delisted on Jun 10, 2026; its insiders filed their last Form 4 on Jun 12, 2026; 451 institutions reported holding it in 13F filings for Q1 2026, worth $9.69B in total; Soros Fund Management was the only superinvestor holding it.
13F holders, Q1 2026
Institutional positions in Masimo Corp as of Mar 31, 2026. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works
MASI is no longer listed, so this page shows Q1 2026. 13F filings for later quarters list far fewer holders.
- Institutional holders
- 451
- +65 vs. Q4 2025
- Shares held
- 54.6M
- +4.00M (+7.9%) vs. Q4 2025
- Total value
- $9.69B
- +$3.10B (+47.2%) vs. Q4 2025
- New holders
- 136
- 140 more added
- Sold out
- 71
- 107 more reduced
6 institutions that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q4 2025: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting MASI on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.
| Quarter | Holders | Value |
|---|---|---|
| Q2 2026 | 2 | $16.2K |
| Q1 2026 | 451 | $9.69B |
| Q4 2025 | 392 | $7.20B |
| Q3 2025 | 358 | $8.29B |
| Q2 2025 | 379 | $9.68B |
| Q1 2025 | 393 | $9.02B |
| Q4 2024 | 366 | $8.50B |
| Q3 2024 | 362 | $6.72B |
| Q2 2024 | 352 | $6.24B |
| Q1 2024 | 339 | $7.59B |
| Q4 2023 | 342 | $5.91B |
| Q3 2023 | 357 | $4.18B |
| Q2 2023 | 415 | $7.56B |
| Q1 2023 | 428 | $8.30B |
| Q4 2022 | 405 | $6.58B |
| Q3 2022 | 418 | $6.54B |
| Q2 2022 | 417 | $5.81B |
| Q1 2022 | 457 | $6.61B |
| Q4 2021 | 520 | $13.6B |
| Q3 2021 | 475 | $12.5B |
| Q2 2021 | 459 | $11.1B |
| Q1 2021 | 481 | $10.3B |
Institutions, Q1 2026
Shares, value and share of portfolio for each institution holding Masimo Corp; share changes are against Q4 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Polar Asset Management Partners Inc. | 232,026 | $41.3M | 0.98% | +232,026 | New |
| Renaissance Technologies LLC | 239,500 | $42.6M | 0.07% | +179,600+299.8% | Added |
| Slotnik Capital, LLC | 240,300 | $42.7M | 12.70% | +240,300 | New |
| Amundi | 243,143 | $43.2M | 0.01% | +199,283+454.4% | Added |
| Nuance Investments, LLC | 244,704 | $43.5M | 6.07% | +244,704 | New |
| HRT Financial LP | 264,837 | $47.1M | 0.12% | +172,061+185.5% | Added |
| Whitebox Advisors LLC | 270,001 | $48.0M | 0.68% | +270,001 | New |
| Citadel Advisors LLC | 281,366 | $50.0M | 0.04% | +238,314+553.5% | Added |
| Vanguard Fiduciary Trust Co | 289,867 | $51.6M | 0.01% | +289,867 | New |
| Qube Research & Technologies Ltd | 291,481 | $51.8M | 0.07% | −2,055−0.7% | Reduced |
| Bank of New York Mellon Corp | 306,400 | $54.5M | 0.01% | −2,085−0.7% | Reduced |
| Capitolis Liquid Global Markets LLC | 309,102 | $55.0M | 0.35% | +309,102 | New |
| Highland Capital Management Fund Advisors, L.P. | 310,130 | $55.2M | 3.85% | +310,130 | New |
| Fort Baker Capital Management LP | 312,720 | $55.6M | 4.93% | +312,720 | New |
| CI Private Wealth, LLC | 321,600 | $57.2M | 0.08% | −18,630−5.5% | Reduced |
| Hudson Bay Capital Management LP | 330,679 | $58.8M | 0.35% | +330,679 | New |
| Alliancebernstein L.P. | 455,354 | $59.2M | 0.02% | +401,131+739.8% | Added |
| Westfield Capital Management Co LP | 341,229 | $60.7M | 0.25% | −1,180,820−77.6% | Reduced |
| Gotham Asset Management, LLC | 341,468 | $60.7M | 0.19% | −726−0.2% | Reduced |
| Capital Research Global Investors | 359,058 | $63.9M | 0.01% | −278,836−43.7% | Reduced |
| Charles Schwab Investment Management Inc | 386,898 | $68.8M | 0.01% | +25,002+6.9% | Added |
| Squarepoint Ops LLC | 389,359 | $69.3M | 0.15% | −194,388−33.3% | Reduced |
| Northern Trust Corp | 390,437 | $69.4M | 0.01% | +9,973+2.6% | Added |
| Neuberger Berman Group LLC | 403,309 | $71.7M | 0.05% | +398,303+7,956.5% | Added |
| O'Connor Alternative Investments LLC | 412,903 | $73.4M | 3.85% | +412,903 | New |
| CNH Partners LLC | 416,956 | $73.9M | 1.21% | +416,956 | New |
| Magnetar Financial LLC | 427,081 | $76.0M | 0.77% | +421,626+7,729.2% | Added |
| UBS Group AG | 468,257 | $83.3M | 0.01% | −131,017−21.9% | Reduced |
| HSBC Holdings PLC | 473,434 | $84.3M | 0.05% | +473,434 | New |
| Vivaldi Asset Management, LLC | 479,403 | $85.3M | 4.48% | +479,403 | New |
| FIL Ltd | 482,000 | $85.7M | 0.07% | +482,000 | New |
| SG Americas Securities, LLC | 522,824 | $93.0M | 0.10% | +506,395+3,082.3% | Added |
| Citigroup Inc | 533,388 | $94.9M | 0.06% | +412,157+340.0% | Added |
| JPMorgan Chase & Co | 572,645 | $101.5M | 0.01% | +454,847+386.1% | Added |
| Davidson Kempner Capital Management LP | 585,988 | $104.2M | 1.85% | +585,988 | New |
| Morgan Stanley | 752,417 | $133.8M | 0.01% | −168,318−18.3% | Reduced |
| Balyasny Asset Management LLC | 770,986 | $137.1M | 0.27% | +770,986 | New |
| AQR Capital Management LLC | 831,966 | $147.4M | 0.07% | −259,360−23.8% | Reduced |
| Geode Capital Management, LLC | 956,736 | $170.2M | 0.01% | +2,760+0.3% | Added |
| Goldman Sachs Group Inc | 984,192 | $175.1M | 0.02% | +347,494+54.6% | Added |
| Millennium Management LLC | 988,853 | $175.9M | 0.13% | +800,888+426.1% | Added |
| State Street Corp | 1,437,724 | $255.7M | 0.01% | +22,528+1.6% | Added |
| FMR LLC | 1,450,823 | $258.1M | 0.01% | −6,413,341−81.6% | Reduced |
| Vanguard Portfolio Management LLC | 2,006,861 | $357.0M | 0.02% | +2,006,861 | New |
| Vanguard Capital Management LLC | 2,050,045 | $364.6M | 0.01% | +2,050,045 | New |
| Massachusetts Financial Services Co | 2,342,790 | $416.7M | 0.14% | −321,085−12.1% | Reduced |
| HBK Investments L P | 2,576,109 | $458.2M | 5.77% | +2,576,109 | New |
| Barclays PLC | 2,743,985 | $488.1M | 0.17% | +2,685,627+4,602.0% | Added |
| Pentwater Capital Management LP | 3,176,000 | $564.9M | 4.01% | +3,176,000 | New |
| Politan Capital Management LP | 4,589,648 | $816.4M | 82.89% | 00.0% | Unchanged |
| BlackRock, Inc. | 4,644,578 | $826.1M | 0.01% | −4,211,041−47.6% | Reduced |
| T. Rowe Price Investment Management, Inc. | 0 | $0 | 0.00% | −2,330,158−100.0% | Sold out |
| Naya Capital Management UK Ltd | 0 | $0 | 0.00% | −1,560,697−100.0% | Sold out |
| Alyeska Investment Group, L.P. | 0 | $0 | 0.00% | −1,259,307−100.0% | Sold out |
| RTW Investments, LP | 0 | $0 | 0.00% | −683,294−100.0% | Sold out |
| Viking Global Investors LPSuperinvestorViking Global Investors | 0 | $0 | 0.00% | −514,340−100.0% | Sold out |
| Bamco Inc | 0 | $0 | 0.00% | −373,899−100.0% | Sold out |
| Parkman Healthcare Partners LLC | 0 | $0 | 0.00% | −200,000−100.0% | Sold out |
| DF Dent & Co Inc | 0 | $0 | 0.00% | −142,626−100.0% | Sold out |
| TD Asset Management Inc | 0 | $0 | 0.00% | −114,514−100.0% | Sold out |
| Falcon Edge Capital, LP | 0 | $0 | 0.00% | −75,552−100.0% | Sold out |
| Swedbank AB | 0 | $0 | 0.00% | −59,500−100.0% | Sold out |
| Assenagon Asset Management S.A. | 0 | $0 | 0.00% | −53,525−100.0% | Sold out |
| Capital Fund Management S.A. | 0 | $0 | 0.00% | −47,586−100.0% | Sold out |
| Sofinnova Investments, Inc. | 0 | $0 | 0.00% | −46,201−100.0% | Sold out |
| Walleye Capital LLC | 0 | $0 | 0.00% | −42,049−100.0% | Sold out |
| Nordea Investment Management AB | 0 | $0 | 0.00% | −28,319−100.0% | Sold out |
| Campbell & CO Investment Adviser LLC | 0 | $0 | 0.00% | −27,783−100.0% | Sold out |
| Logan Capital Management Inc | 0 | $0 | 0.00% | −26,505−100.0% | Sold out |
| Gluskin Sheff & Assoc Inc | 0 | $0 | 0.00% | −25,805−100.0% | Sold out |
| Susquehanna International Group, LLP | 0 | $0 | 0.00% | −16,849−100.0% | Sold out |
| Dark Forest Capital Management LP | 0 | $0 | 0.00% | −16,385−100.0% | Sold out |
| Deerfield Management Company, L.P. (Series C) | 0 | $0 | 0.00% | −16,147−100.0% | Sold out |
| Kayne Anderson Rudnick Investment Management LLC | 0 | $0 | 0.00% | −15,932−100.0% | Sold out |
| Sumitomo Mitsui Trust Holdings, Inc. | 0 | $0 | 0.00% | −14,572−100.0% | Sold out |
| Trexquant Investment LP | 0 | $0 | 0.00% | −13,920−100.0% | Sold out |
| Lecap Asset Management Ltd | 0 | $0 | 0.00% | −13,196−100.0% | Sold out |
| XTX Topco Ltd | 0 | $0 | 0.00% | −12,746−100.0% | Sold out |
| Harbor Capital Advisors, Inc. | 0 | $0 | 0.00% | −9,599−100.0% | Sold out |
| Dynamic Technology Lab Private Ltd | 0 | $0 | 0.00% | −9,480−100.0% | Sold out |
| Birchview Capital, LP | 0 | $0 | 0.00% | −8,280−100.0% | Sold out |
| OP Asset Management Ltd | 0 | $0 | 0.00% | −8,207−100.0% | Sold out |
| Wellington Management Group LLP | 0 | $0 | 0.00% | −7,832−100.0% | Sold out |
| Graham Capital Management, L.P. | 0 | $0 | 0.00% | −6,017−100.0% | Sold out |
| Cinctive Capital Management LP | 0 | $0 | 0.00% | −5,681−100.0% | Sold out |
| Malaga Cove Capital, LLC | 0 | $0 | 0.00% | −5,366−100.0% | Sold out |
| Exchange Traded Concepts, LLC | 0 | $0 | 0.00% | −5,101−100.0% | Sold out |
| Laird Norton Trust Company, LLC | 0 | $0 | 0.00% | −4,778−100.0% | Sold out |
| Capstone Investment Advisors, LLC | 0 | $0 | 0.00% | −4,718−100.0% | Sold out |
| Stifel Financial Corp | 0 | $0 | 0.00% | −4,526−100.0% | Sold out |
| NEOS Investment Management LLC | 0 | $0 | 0.00% | −4,342−100.0% | Sold out |
| Tema ETFs LLC | 0 | $0 | 0.00% | −4,342−100.0% | Sold out |
| Gsa Capital Partners LLP | 0 | $0 | 0.00% | −3,682−100.0% | Sold out |
| CenterBook Partners LP | 0 | $0 | 0.00% | −3,148−100.0% | Sold out |
| Farringdon Capital, Ltd. | 0 | $0 | 0.00% | −3,141−100.0% | Sold out |
| Havemeyer Place LP | 0 | $0 | 0.00% | −3,020−100.0% | Sold out |
| State of Wyoming | 0 | $0 | 0.00% | −2,896−100.0% | Sold out |
| 111 Capital | 0 | $0 | 0.00% | −2,871−100.0% | Sold out |
| Ensign Peak Advisors, Inc | 0 | $0 | 0.00% | −2,711−100.0% | Sold out |
| Oppenheimer Asset Management Inc. | 0 | $0 | 0.00% | −2,503−100.0% | Sold out |