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MASI

Masimo
MASI

Delisted

MASI was delisted on the 9th of June, 2026.

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326 hedge funds and large institutions have $3.84B invested in Masimo in 2018 Q1 according to their latest regulatory filings, with 51 funds opening new positions, 112 increasing their positions, 116 reducing their positions, and 56 closing their positions.

New
Increased
Maintained
Reduced
Closed

25% more call options, than puts

Call options by funds: $14M | Put options by funds: $11.2M

5% more capital invested

Capital invested by funds: $3.65B → $3.84B (+$193M)

1.24% more ownership

Funds ownership: 83.26% → 84.51% (+1.2%)

0% more funds holding in top 10

Funds holding in top 10: 1 → 1 (0)

3% less repeat investments, than reductions

Existing positions increased: 112 | Existing positions reduced: 116

9% less first-time investments, than exits

New positions opened: 51 | Existing positions closed: 56

4% less funds holding

Funds holding: 338 → 326 (-12)

Holders
326
Holders Change
-12
Holders Change %
-3.55%
% of All Funds
7.45%
Holding in Top 10
1
Holding in Top 10 Change
–
Holding in Top 10 Change %
–
% of All Funds
0.02%
New
51
Increased
112
Reduced
116
Closed
56
Calls
$14M
Puts
$11.2M
Net Calls
+$2.76M
Net Calls Change
+$4.05M

Top Buyers

Rank Fund Capital Flow
1
Ameriprise
Ameriprise
Minnesota
+$121M
2
Citadel Advisors
Citadel Advisors
Florida
+$82.1M
3
Point72 Asset Management
Point72 Asset Management
Connecticut
+$60.8M
4
HM
HealthCor Management
New York
+$50.1M
5
CIP
Champlain Investment Partners
Vermont
+$43.1M

Top Sellers

Rank Fund Capital Flow
1
Arrowstreet Capital
Arrowstreet Capital
Massachusetts
-$80.3M
2
Robeco Institutional Asset Management
Robeco Institutional Asset Management
Netherlands
-$77M
3
Vanguard Group
Vanguard Group
Pennsylvania
-$63.4M
4
Acadian Asset Management
Acadian Asset Management
Massachusetts
-$60.3M
5
JP Morgan Chase
JP Morgan Chase
New York
-$30.4M

MASI Hedge Fund Activity: Q1 2018 in Review

326 of the 4,373 institutional investors tracked by Wall St. Rank reported a position in Masimo (MASI) for Q1 2018, worth a combined $3.84B — up 5.3% from $3.65B a quarter earlier.

Sellers outnumbered buyers: 56 funds closed out of MASI and 51 opened new positions — a net loss of 5 holders — while 116 trimmed existing stakes and 112 added.

The largest buyer was Ameriprise, adding an estimated $121M. The largest seller was Arrowstreet Capital, cutting an estimated $80.3M.

  • 326 institutional investors held Masimo (MASI) as of Q1 2018, down from 338 in Q4 2017.
  • Funds reported $3.84B of Masimo stock for Q1 2018, up 5.3% quarter-over-quarter.
  • 51 funds opened new Masimo positions in Q1 2018 and 56 closed out, a net change of -5 holders.
  • The largest Masimo buyer in Q1 2018 was Ameriprise, an estimated $121M added.
  • The largest Masimo seller in Q1 2018 was Arrowstreet Capital, an estimated $80.3M sold.

Based on aggregated 13F filings for Q1 2018.