MASIMO CORP MASI*

MM

Latest 13F among current holders filed 11 days ago (Jun 24, 2026)

Institutional holders
445
+54 QoQ
13F value
$9.48B
+29.5% QoQ
Smart-money holders
28
signal tier ≥ 2
New smart buyers
20
Q1 2026
Options barometer
10.8×
$266.6M calls / $24.6M puts

Institutional value by quarter

$7.93B
Q1 2024
$6.26B
Q2 2024
$6.74B
Q3 2024
$8.51B
Q4 2024
$9.03B
Q1 2025
$9.68B
Q2 2025
$8.31B
Q3 2025
$7.32B
Q4 2025
$9.48B
Q1 2026

Number of holders

341
Q1 2024
353
Q2 2024
363
Q3 2024
367
Q4 2024
394
Q1 2025
380
Q2 2025
358
Q3 2025
391
Q4 2025
445
Q1 2026

Who owns MASI*?

Q1 2026 filings
FundTypeSharesValue% of fundChange
BlackRock, Inc. Index provider4.6M$826.1M0.0%-47.6%
Politan Capital Management LP ★2Fundamental diversified4.6M$816.4M82.9%Held
Pentwater Capital Management LP ★2Fundamental concentrated3.2M$564.9M4.0%New
BARCLAYS PLC Bank broker2.7M$488.1M0.2%+4602.0%
HBK INVESTMENTS L P ★2Fundamental diversified2.6M$458.2M6.2%New
MASSACHUSETTS FINANCIAL SERVICES CO /MA/ Other2.3M$416.7M0.1%-12.1%
VANGUARD CAPITAL MANAGEMENT LLC Diversified mechanical2.1M$364.6M0.0%
VANGUARD PORTFOLIO MANAGEMENT LLC Diversified mechanical2.0M$357.0M0.0%
FMR LLC Long only active1.5M$258.1M0.0%-81.6%
STATE STREET CORP Index provider1.4M$255.7M0.0%+1.6%
MILLENNIUM MANAGEMENT LLC Multistrat pod988.9K$175.9M0.1%+426.1%
GOLDMAN SACHS GROUP INC Bank broker984.2K$175.1M0.0%+54.6%
GEODE CAPITAL MANAGEMENT, LLC Index provider956.7K$170.2M0.0%+0.3%
AQR CAPITAL MANAGEMENT LLC Quant stat arb832.0K$147.4M0.1%-23.8%
Balyasny Asset Management L.P. Multistrat pod771.0K$137.1M0.3%New
MORGAN STANLEY Bank broker752.4K$133.8M0.0%-18.3%
JPMORGAN CHASE & CO Bank broker572.6K$101.5M0.0%+386.1%
CITIGROUP INC Bank broker533.4K$94.9M0.1%+340.0%
SG Americas Securities, LLC Diversified mechanical522.8K$93.0M0.1%+3082.3%
FIL Ltd Other482.0K$85.7M0.1%New
First Trust Capital Management L.P. Quant stat arb479.4K$85.3M4.5%New
HSBC HOLDINGS PLC Bank broker473.4K$84.3M0.1%New
UBS Group AG Bank broker468.3K$83.3M0.0%-21.9%
Magnetar Financial LLC Quant stat arb427.1K$76.0M0.8%+7729.2%
AQR Arbitrage LLC Other417.0K$73.9M1.4%New
NEUBERGER BERMAN GROUP LLC Diversified mechanical403.3K$71.7M0.1%+7956.5%
NORTHERN TRUST CORP Index provider390.4K$69.4M0.0%+2.6%
Squarepoint Ops LLC Quant stat arb389.4K$69.3M0.1%-33.3%
CHARLES SCHWAB INVESTMENT MANAGEMENT INC Index provider386.9K$68.8M0.0%+6.9%
Capital Research Global Investors Long only active359.1K$63.9M0.0%-43.7%
Gotham Asset Management, LLC Diversified mechanical341.5K$60.7M0.2%-0.2%
WESTFIELD CAPITAL MANAGEMENT CO LP Other341.2K$60.7M0.3%-77.6%
ALLIANCEBERNSTEIN L.P. Long only active455.4K$59.2M0.0%+739.8%
Hudson Bay Capital Management LP Multistrat pod330.7K$58.8M0.4%New
Corient Private Wealth LLC Diversified mechanical321.6K$57.2M0.1%-52.8%
Fort Baker Capital Management LP ★2Fundamental concentrated312.7K$55.6M5.7%New
NEXPOINT ASSET MANAGEMENT, L.P. ★2Fundamental diversified310.1K$55.2M3.8%New
CAPITOLIS LIQUID GLOBAL MARKETS LLC Other309.1K$55.0M0.3%
Bank of New York Mellon Corp Diversified mechanical306.4K$54.5M0.0%-0.7%
Qube Research & Technologies Ltd Quant stat arb291.5K$51.8M0.1%-0.7%
VANGUARD FIDUCIARY TRUST CO Diversified mechanical289.9K$51.6M0.0%
CITADEL ADVISORS LLC Multistrat pod281.4K$50.0M0.0%+553.5%
WHITEBOX ADVISORS LLC Other270.0K$48.0M2.7%New
HRT FINANCIAL LP Diversified mechanical264.8K$47.1M0.1%+185.5%
NUANCE INVESTMENTS, LLC ★3Fundamental concentrated244.7K$43.5M6.1%New
Amundi Diversified mechanical243.1K$43.2M0.0%+454.4%
Slotnik Capital, LLC ★2Fundamental concentrated240.3K$42.7M12.7%New
RENAISSANCE TECHNOLOGIES LLC Quant stat arb239.5K$42.6M0.1%+299.8%
Polar Asset Management Partners Inc. Quant stat arb232.0K$41.3M1.3%New
BANK OF AMERICA CORP /DE/ Bank broker232.0K$41.3M0.0%-18.5%

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