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WESTFIELD CAPITAL MANAGEMENT CO LP

Position in MASI — Masimo Corp

CIK 1177719 BOSTON, MA

Position in MASI

as of Mar 31, 2026 · filed May 11, 2026
Position Value
$60,694,402
-$137,263,290 QoQ
Shares Held
341,229
-77.6% QoQ
Ownership
0.652%
of shares outstanding
% of Portfolio
0.25%
of 13F equity value
Holder Rank
#32
of 445 holders
Holding Since
Mar 2020
17 quarters on record
Voting authority Sole 90.94420462504652.ToString("F0")% Shared 0.ToString("F0")% None 9.055795374953476.ToString("F0")%

Common Shares in MASI Over Time

Shares Held

Position Value (USD)

Position in Medical Devices

Healthcare · as of Mar 31, 2026

WESTFIELD CAPITAL MANAGEMENT CO LP holds $120,408,739 across 7 Medical Devices names. MASI ranks #1 (50.4% of the industry book) .

# Ticker Company Shares Value (USD) Open
1 MASI
Masimo Corp
This page
341,229 $60,694,402

All Filings in MASI

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17 filing rows on record
Report Date Value (USD) Shares
2026-03-31 $60,694,402 341,229
2025-12-31 $197,957,692 1,522,049
2025-09-30 $209,410,337 1,419,250
2025-06-30 $198,701,968 1,181,203
2025-03-31 $111,868,401 671,479
2024-12-31 $127,092,227 768,858
2024-09-30 $185,869,486 1,394,056
2024-06-30 $142,524,534 1,131,686
2024-03-31 $100,753,785 686,100
2023-12-31 $95,933,571 818,476
2023-09-30 $52,930,750 603,681
2023-06-30 $156,947,625 953,799
2021-03-31 $47,733,912 207,846
2020-12-31 $63,724,952 237,443
2020-09-30 $68,585,580 290,543
2020-06-30 $69,246,718 303,727
2020-03-31 $76,742,022 433,277