MASIMO CORP (MASI) Institutional Ownership Changes & 13F Activity

MASIMO CORP (MASI). Institutional ownership data tracks hedge funds, asset managers, and other institutional investors based on recent SEC Form 13F filings. This page analyzes institutional buying and selling activity, new holdings, and sold-out positions among tracked filers. Notable filers include Renaissance Technologies LLC, Viking Global Investors, First Eagle U.S. Value, Durable Capital Partners, and Fundsmith.

Portfolio quarterNameTypeQuantityRemainingReported stock balance
Q1 2016Renaissance Technologies LLCBuy10,300232,700$9,736
Q1 2016Jensen Investment ManagementBuy10,26010,260$429
Q4 2015Renaissance Technologies LLCBuy109,200222,400$9,232
Q3 2015Renaissance Technologies LLCSell-42,400113,200$4,365
Q2 2015Renaissance Technologies LLCBuy12,900155,600$6,028
Q1 2015Renaissance Technologies LLCBuy42,600142,700$4,706
Q4 2014Renaissance Technologies LLCSell-236,100100,100$2,637
Q3 2014Renaissance Technologies LLCBuy73,965336,200$7,154
Q2 2014Renaissance Technologies LLCBuy201,635262,235$6,189
Q4 2013Bares Capital ManagementSell-237,2622,153,144$62,936
Q3 2013Bares Capital ManagementSell-647,0652,390,406$63,676
Q3 2013Renaissance Technologies LLCSell-396,60060,600$1,614
Q2 2013Bares Capital ManagementBuy3,037,4713,037,471$64,394
Q2 2013Renaissance Technologies LLCBuy457,200457,200$9,693

Frequently asked questions about MASI activity

  • Which institutional owners are buying MASI?

    Institutional owners buying MASI include investors who have either initiated new positions or increased their existing holdings based on recent SEC 13F filings. The activity table above highlights which funds added shares in the latest reporting periods and how their positions changed over time.

  • What does "buy" mean in MASI activity?

    "Buy" means an investor increased their reported position in MASI compared to the prior reporting period. This reflects growing exposure to MASIMO CORP (MASI) rather than necessarily a brand-new position (though new positions also appear as buys when prior quantity was zero).

  • Is institutional interest in MASI increasing?

    Institutional interest in MASI can be assessed by comparing the number of tracked funds adding or increasing positions versus those trimming or exiting across the periods shown. A higher number of additions typically signals increasing participation among large filers, but it should be read alongside position sizes and the full table.

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