Vault-13

MASIMO CORP MASI

COM · Common Stock · CUSIP 574795100 · ISIN US5747951003

392 institutional holders +34 vs Q3 2025
56,221,46256.2m shares reported held*
$7.3bnreported value*
73 new 101 added 133 reduced 49 sold out net sold ≈ $51.4m (-395.1k shares)

* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($10.3m this quarter). Holder counts are more reliable. Implied quarter-end price ≈ $130.08. Options: 4 managers hold calls ($3.6m notional), 5 hold puts ($8.4m).

Trends to Q4 2025

Institutional holders

Managers reporting a position, each quarter

0200400600Q3 22: 420Q4 22: 405Q1 23: 429Q2 23: 417Q3 23: 358Q4 23: 343Q1 24: 341Q2 24: 353Q3 24: 363Q4 24: 367Q1 25: 394Q2 25: 380Q3 25: 358Q4 25: 392392Q3 22Q2 23Q1 24Q4 24Q4 25
Numbers
QuarterHolders
Q3 2022420
Q4 2022405
Q1 2023429
Q2 2023417
Q3 2023358
Q4 2023343
Q1 2024341
Q2 2024353
Q3 2024363
Q4 2024367
Q1 2025394
Q2 2025380
Q3 2025358
Q4 2025392

Buyers vs sellers

Managers adding to or starting a position, vs cutting or selling out

Bought or addedCut or sold out
4000400Q1 24: 140 bought or addedQ1 24: 177 cut or sold outQ2 24: 170 bought or addedQ2 24: 151 cut or sold outQ2 24Q3 24: 169 bought or addedQ3 24: 170 cut or sold outQ4 24: 162 bought or addedQ4 24: 169 cut or sold outQ4 24Q1 25: 206 bought or addedQ1 25: 161 cut or sold outQ2 25: 166 bought or addedQ2 25: 195 cut or sold outQ2 25Q3 25: 164 bought or addedQ3 25: 184 cut or sold outQ4 25: 174 bought or addedQ4 25: 182 cut or sold outQ4 25
Numbers
QuarterBought or addedCut or sold out
Q1 2024140177
Q2 2024170151
Q3 2024169170
Q4 2024162169
Q1 2025206161
Q2 2025166195
Q3 2025164184
Q4 2025174182

Calls vs puts

Options held, notional value, last 4 quarters. P/C = puts ÷ calls

CallsPuts
$0$5m$10m$15mQ1 25 calls: $7.3mQ1 25 puts: $5.7mQ1 25P/C 0.78Q2 25 calls: $10.1mQ2 25 puts: $3.9mQ2 25P/C 0.38Q3 25 calls: $5.5mQ3 25 puts: $5.5mQ3 25P/C 1.00Q4 25 calls: $3.6mQ4 25 puts: $8.4mQ4 25P/C 2.37
Numbers
QuarterCallsPutsP/C
Q1 2025$7.3m$5.7m0.78
Q2 2025$10.1m$3.9m0.38
Q3 2025$5.5m$5.5m1.00
Q4 2025$3.6m$8.4m2.37

Biggest buyers

NAYA CAPITAL MANAGEMENT UK LTD New +1,560,697+1.6m
AQR CAPITAL MANAGEMENT LLC Added +1,060,292+1.1m
T. Rowe Price Investment Management, Inc. Added +803,688+803.7k
UBS Group AG Added +429,474+429.5k
Corient Private Wealth LP Added +345,745+345.7k
Qube Research & Technologies Ltd New +293,536+293.5k
Schonfeld Strategic Advisors LLC Added +254,152+254.2k
MORGAN STANLEY Added +230,134+230.1k
Gotham Asset Management, LLC Added +213,168+213.2k
Parkman Healthcare Partners LLC New +200,000+200.0k

Biggest sellers

BlackRock, Inc. Reduced -1,505,472-1.5m
Capital Research Global Investors Reduced -1,216,234-1.2m
Durable Capital Partners LP Sold out -620,619-620.6k
VIKING GLOBAL INVESTORS LP Reduced -559,093-559.1k
VANGUARD GROUP INC Reduced -461,225-461.2k
Sumitomo Mitsui Trust Group, Inc. Reduced -382,676-382.7k
FMR LLC Reduced -349,557-349.6k
PRICE T ROWE ASSOCIATES INC /MD/ Reduced -301,352-301.4k
COMERICA BANK Reduced -221,194-221.2k
ADAGE CAPITAL PARTNERS GP, L.L.C. Sold out -150,000-150.0k

Biggest calls

SUSQUEHANNA INTERNATIONAL GROUP, LLP Reduced $2.5m19.3k shares
CITADEL ADVISORS LLC Reduced $663.3k5.1k shares
JANE STREET GROUP, LLC Reduced $364.2k2.8k shares
GROUP ONE TRADING LLC Unchanged $13.0k100 shares

Biggest puts

SUSQUEHANNA INTERNATIONAL GROUP, LLP Added $6.4m49.4k shares
JANE STREET GROUP, LLC Added $949.4k7.3k shares
CITADEL ADVISORS LLC Added $403.2k3.1k shares
GROUP ONE TRADING LLC New $325.1k2.5k shares
SIG BROKERAGE, LP New $325.1k2.5k shares

Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.

Major shareholders (over 5%)

Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.

HolderStakeChangeShares Last filed
BlackRock, Inc. 13G · institution filed 2025-02-07 7.9% 4.2m 2025-02-07
KIANI JOE E 13G · exempt (held before listing) -3.8 pts · filed 2026-05-14 6.5% -3.8 pts 3.7m 2026-05-14
BARCLAYS PLC 13G · institution new · filed 2026-05-14 5.5% new 2.9m 2026-05-14

Fell to 5% or below in the last year: Pentwater Capital Management LP (0.0%, 2026-08-14), Politan Capital Management LP (0.0%, 2026-06-11), BlackRock Portfolio Management LLC (0.2%, 2026-04-30; now reported by BlackRock, Inc.), VANGUARD GROUP INC (0.0%, 2026-03-27), FMR LLC (4.5%, 2026-03-06)

Holders, Q4 2025

#ManagerLocationShares Value% of their portfolioChangeShares change
1 BlackRock, Inc. 0.02% of their portfolio New York, NY 8,855,6198.9m $1.2bn $1.2bn 0.02% Reduced -1.5m -1,505,472
2 FMR LLC 0.05% of their portfolio BOSTON, MA 7,864,1647.9m $1.0bn $1.0bn 0.05% Reduced -349.6k -349,557
3 Politan Capital Management LP 71.01% of their portfolio NEW YORK, NY 4,589,6484.6m $596.9m $596.9m 71.01% Unchanged
4 VANGUARD GROUP INC 0.01% of their portfolio Valley Forge, PA 4,348,7864.3m $565.6m $565.6m 0.01% Reduced -461.2k -461,225
5 T. Rowe Price Investment Management, Inc. 0.15% of their portfolio BALTIMORE, MD 2,930,4512.9m $381.1m $381.1m 0.15% Added +803.7k +803,688
6 MASSACHUSETTS FINANCIAL SERVICES CO /MA/ 0.11% of their portfolio Boston, MA 2,663,8752.7m $346.5m $346.5m 0.11% Added +43.9k +43,915
7 NAYA CAPITAL MANAGEMENT UK LTD 15.28% of their portfolio London, X0 1,560,6971.6m $203.0m $203.0m 15.28% New
8 WESTFIELD CAPITAL MANAGEMENT CO LP 0.82% of their portfolio BOSTON, MA 1,522,0491.5m $198.0m $198.0m 0.82% Added +102.8k +102,799
9 STATE STREET CORP 0.01% of their portfolio BOSTON, MA 1,415,1961.4m $184.1m $184.1m 0.01% Reduced -69.3k -69,275
10 Alyeska Investment Group, L.P. 0.46% of their portfolio CHICAGO, IL 1,259,3071.3m $163.8m $163.8m 0.46% Reduced -121.8k -121,778
11 AQR CAPITAL MANAGEMENT LLC 0.07% of their portfolio Greenwich, CT 1,091,3261.1m $141.9m $141.9m 0.07% Added +1.1m +1,060,292
12 GEODE CAPITAL MANAGEMENT, LLC 0.01% of their portfolio BOSTON, MA 953,976954.0k $124.1m $124.1m 0.01% Added +11.5k +11,537
13 MORGAN STANLEY 0.01% of their portfolio NEW YORK, NY 920,735920.7k $119.8m $119.8m 0.01% Added +230.1k +230,134
14 RTW INVESTMENTS, LP 0.89% of their portfolio NEW YORK, NY 683,294683.3k $88.9m $88.9m 0.89% Unchanged
15 Corient Private Wealth LP 0.06% of their portfolio MIAMI, FL 681,960682.0k $88.7m $88.7m 0.06% Added +345.7k +345,745
16 Capital Research Global Investors 0.02% of their portfolio Los Angeles, CA 637,894637.9k $83.0m $83.0m 0.02% Reduced -1.2m -1,216,234
17 GOLDMAN SACHS GROUP INC 0.01% of their portfolio NEW YORK, NY 636,698636.7k $82.8m $82.8m 0.01% Reduced -107.7k -107,704
18 Liontrust Investment Partners LLP 1.21% of their portfolio LONDON, X0 627,796627.8k $81.7m $81.7m 1.21% Reduced -54.1k -54,099
19 UBS Group AG 0.02% of their portfolio ZURICH, V8 599,274599.3k $77.9m $77.9m 0.02% Added +429.5k +429,474
20 Squarepoint Ops LLC 0.15% of their portfolio NEW YORK, NY 583,747583.7k $75.9m $75.9m 0.15% Reduced -37.2k -37,185
21 VIKING GLOBAL INVESTORS LP 0.18% of their portfolio STAMFORD, CT 514,340514.3k $66.9m $66.9m 0.18% Reduced -559.1k -559,093
22 SCHRODER INVESTMENT MANAGEMENT GROUP 0.05% of their portfolio London, X0 475,504475.5k $62.3m $62.3m 0.05% Added +138.9k +138,854
23 AMERIPRISE FINANCIAL INC 0.01% of their portfolio MINNEAPOLIS, MN 468,407468.4k $60.9m $60.9m 0.01% Added +7.5k +7,456
24 NORTHERN TRUST CORP 0.01% of their portfolio CHICAGO, IL 380,464380.5k $49.5m $49.5m 0.01% Reduced -11.7k -11,678
25 NORGES BANK 0.01% of their portfolio OSLO, Q8 377,421377.4k $49.1m $49.1m 0.01% Not comparable
26 BAMCO INC /NY/ 0.13% of their portfolio NEW YORK, NY 373,899373.9k $48.6m $48.6m 0.13% Reduced -14.8k -14,848
27 CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.01% of their portfolio SAN FRANCISCO, CA 361,896361.9k $47.1m $47.1m 0.01% Reduced -2.6k -2,561
28 Gotham Asset Management, LLC 0.16% of their portfolio NEW YORK, NY 342,194342.2k $44.5m $44.5m 0.16% Added +213.2k +213,168
29 Invesco Ltd. 0.00% of their portfolio ATLANTA, GA 319,308319.3k $41.5m $41.5m 0.00% Reduced -2.1k -2,055
30 Bank of New York Mellon Corp 0.01% of their portfolio NEW YORK, NY 308,485308.5k $40.1m $40.1m 0.01% Reduced -4.1k -4,133
31 Qube Research & Technologies Ltd 0.05% of their portfolio LONDON, X0 293,536293.5k $38.2m $38.2m 0.05% New
32 BANK OF AMERICA CORP /DE/ 0.00% of their portfolio CHARLOTTE, NC 284,702284.7k $37.0m $37.0m 0.00% Reduced -120.4k -120,359
33 Schonfeld Strategic Advisors LLC 0.17% of their portfolio NEW YORK, NY 265,036265.0k $34.5m $34.5m 0.17% Added +254.2k +254,152
34 BNP PARIBAS ASSET MANAGEMENT Holding S.A. 0.03% of their portfolio Paris, I0 232,565232.6k $30.2m $30.2m 0.03% Added +67.6k +67,639
35 Nuveen, LLC 0.01% of their portfolio CHARLOTTE, NC 224,068224.1k $29.1m $29.1m 0.01% Reduced -1.6k -1,644
36 MARSHALL WACE, LLP 0.03% of their portfolio LONDON, X0 219,312219.3k $28.5m $28.5m 0.03% Added +85.2k +85,190
37 PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio BALTIMORE, MD 213,594213.6k $27.8m $27.8m 0.00% Reduced -301.4k -301,352
38 Parkman Healthcare Partners LLC 2.48% of their portfolio STAMFORD, CT 200,000200.0k $26.0m $26.0m 2.48% New
39 Erste Asset Management GmbH 0.22% of their portfolio VIENNA, C4 200,000200.0k $26.0m $26.0m 0.22% Added +40.0k +40,000
40 MILLENNIUM MANAGEMENT LLC 0.02% of their portfolio NEW YORK, NY 187,965188.0k $24.4m $24.4m 0.02% Added +171.8k +171,834
41 RAYMOND JAMES FINANCIAL INC 0.01% of their portfolio ST. PETERSBURG, FL 186,510186.5k $24.3m $24.3m 0.01% Reduced -9.5k -9,511
42 AMERICAN CENTURY COMPANIES INC 0.01% of their portfolio KANSAS CITY, MO 178,758178.8k $23.2m $23.2m 0.01% Added +10.4k +10,417
43 DIMENSIONAL FUND ADVISORS LP 0.00% of their portfolio AUSTIN, TX 173,950173.9k $22.6m $22.6m 0.00% Reduced -85.7k -85,718
44 Man Group plc 0.04% of their portfolio LONDON, X0 147,416147.4k $19.2m $19.2m 0.04% New
45 Grantham, Mayo, Van Otterloo & Co. LLC 0.05% of their portfolio Boston, MA 143,825143.8k $18.7m $18.7m 0.05% Reduced -99.0k -98,997
46 DF DENT & CO INC 0.27% of their portfolio BALTIMORE, MD 142,626142.6k $18.6m $18.6m 0.27% Added +34.0k +33,973
47 RHUMBLINE ADVISERS 0.01% of their portfolio BOSTON, MA 124,556124.6k $16.2m $16.2m 0.01% Reduced -2.1k -2,052
48 CITIGROUP INC 0.01% of their portfolio NEW YORK, NY 121,231121.2k $15.8m $15.8m 0.01% Added +4.6k +4,559
49 GW&K Investment Management, LLC 0.13% of their portfolio BOSTON, MA 119,362119.4k $15.5m $15.5m 0.13% Reduced -4.7k -4,685
50 UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio NEW YORK, NY 118,964119.0k $15.5m $15.5m 0.00% Added +9.9k +9,854
51 JPMORGAN CHASE & CO 0.00% of their portfolio NEW YORK, NY 117,798117.8k $15.3m $15.3m 0.00% Reduced -98.1k -98,084
52 TD Asset Management Inc 0.01% of their portfolio Toronto, A6 114,514114.5k $14.9m $14.9m 0.01% Added +6.7k +6,656
53 JANE STREET GROUP, LLC 0.02% of their portfolio NEW YORK, NY 102,881102.9k $13.4m $13.4m 0.02% New
54 PRINCIPAL FINANCIAL GROUP INC 0.01% of their portfolio DES MOINES, IA 97,85897.9k $12.7m $12.7m 0.01% Reduced -4.3k -4,326
55 Bellevue Group AG 0.24% of their portfolio ZURICH, V8 97,28597.3k $12.7m $12.7m 0.24% Added +317 +317
56 HRT FINANCIAL LP 0.05% of their portfolio NEW YORK, NY 92,77692.8k $12.1m $12.1m 0.05% New
57 Legal & General Group Plc 0.00% of their portfolio London, X0 92,43692.4k $12.0m $12.0m 0.00% Reduced -10.2k -10,241
58 Swiss National Bank 0.01% of their portfolio ZURICH, V8 91,10091.1k $11.8m $11.8m 0.01% Added +1.8k +1,800
59 Rockefeller Capital Management L.P. 0.02% of their portfolio NEW YORK, NY 86,41186.4k $11.2m $11.2m 0.02% Reduced -61.0k -61,017
60 Tidal Investments LLC 0.05% of their portfolio Milwaukee, WI 85,29485.3k $11.1m $11.1m 0.05% Reduced -47.3k -47,263
61 Engineers Gate Manager LP 0.13% of their portfolio NEW YORK, NY 83,45883.5k $10.9m $10.9m 0.13% Added +52.7k +52,685
62 GAMCO INVESTORS, INC. ET AL 0.10% of their portfolio GREENWICH, CT 83,00083.0k $10.8m $10.8m 0.10% Reduced -800 -800
63 Alpha Wave Global, LP 1.20% of their portfolio Miami, FL 75,55275.6k $9.8m $9.8m 1.20% Reduced -21.6k -21,550
64 D. E. Shaw & Co., Inc. 0.01% of their portfolio New York, NY 66,01666.0k $8.6m $8.6m 0.01% New
65 California Public Employees Retirement System 0.00% of their portfolio Sacramento, CA 63,35963.4k $8.2m $8.2m 0.00% Reduced -15.1k -15,101
66 RENAISSANCE TECHNOLOGIES LLC 0.01% of their portfolio NEW YORK, NY 59,90059.9k $7.8m $7.8m 0.01% New
67 Swedbank AB 0.01% of their portfolio STOCKHOLM, V7 59,50059.5k $7.7m $7.7m 0.01% Reduced -8.0k -8,000
68 BARCLAYS PLC 0.00% of their portfolio LONDON, X0 58,35858.4k $7.6m $7.6m 0.00% Reduced -19.4k -19,446
69 Quantbot Technologies LP 0.25% of their portfolio NEW YORK, NY 56,92556.9k $7.4m $7.4m 0.25% New
70 Retirement Systems of Alabama 0.02% of their portfolio MONTGOMERY, AL 54,79554.8k $7.1m $7.1m 0.02% Reduced -1.0k -1,036
71 ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio NASHVILLE, TN 54,22354.2k $7.1m $7.1m 0.00% Added +662 +662
72 Assenagon Asset Management S.A. 0.01% of their portfolio SENNINGERBERG, N4 53,52553.5k $7.0m $7.0m 0.01% Added +51.1k +51,068
73 Verition Fund Management LLC 0.04% of their portfolio GREENWICH, CT 53,02053.0k $6.9m $6.9m 0.04% Added +43.6k +43,617
74 BLI - Banque de Luxembourg Investments 0.19% of their portfolio LUXEMBOURG CITY, N4 48,83948.8k $6.4m $6.4m 0.19% Reduced -19.7k -19,661
75 CAPITAL FUND MANAGEMENT S.A. 0.06% of their portfolio PARIS, I0 47,58647.6k $6.2m $6.2m 0.06% Added +13.2k +13,162
76 Sofinnova Investments, Inc. 0.26% of their portfolio Menlo Park, CA 46,20146.2k $6.0m $6.0m 0.26% New
77 Amundi 0.00% of their portfolio Paris, I0 43,86043.9k $5.7m $5.7m 0.00% Reduced -41.0k -41,034
78 CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.01% of their portfolio WEST SACRAMENTO, CA 43,82343.8k $5.7m $5.7m 0.01% Added +468 +468
79 CITADEL ADVISORS LLC 0.00% of their portfolio MIAMI, FL 43,05243.1k $5.6m $5.6m 0.00% Reduced -44.7k -44,698
80 NS Partners Ltd 0.22% of their portfolio LONDON, X0 42,34842.3k $5.5m $5.5m 0.22% Reduced -46 -46
81 Walleye Capital LLC 0.03% of their portfolio NEW YORK, NY 42,04942.0k $5.5m $5.5m 0.03% Reduced -47.3k -47,314
82 NEW YORK STATE TEACHERS RETIREMENT SYSTEM 0.01% of their portfolio ALBANY, NY 40,04840.0k $5.2m $5.2m 0.01% Unchanged
83 STATE BOARD OF ADMINISTRATION OF FLORIDA RETIREMENT SYSTEM 0.01% of their portfolio TALLAHASSEE, FL 39,74939.7k $5.2m $5.2m 0.01% Reduced -1.3k -1,330
84 VOLORIDGE INVESTMENT MANAGEMENT, LLC 0.02% of their portfolio JUPITER, FL 39,55739.6k $5.1m $5.1m 0.02% Added +36.7k +36,694
85 WILSON ASSET MANAGEMENT (INTERNATIONAL) PTY LTD 1.32% of their portfolio SYDNEY, C3 39,43739.4k $5.1m $5.1m 1.32% Added +12.2k +12,203
86 CANADA PENSION PLAN INVESTMENT BOARD 0.00% of their portfolio TORONTO ONTARIO, A6 38,50038.5k $5.0m $5.0m 0.00% Added +22.7k +22,700
87 STRS OHIO 0.02% of their portfolio COLUMBUS, OH 36,91536.9k $4.8m $4.8m 0.02% Added +2 +2
88 MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.00% of their portfolio Toronto, A6 33,18433.2k $4.3m $4.3m 0.00% Reduced -1.0k -1,009
89 GABELLI FUNDS LLC 0.03% of their portfolio Rye, NY 32,70032.7k $4.3m $4.3m 0.03% Unchanged
90 Baird Financial Group, Inc. 0.01% of their portfolio MILWAUKEE, WI 30,67930.7k $4.0m $4.0m 0.01% Reduced -5.2k -5,155
91 NORDEA INVESTMENT MANAGEMENT AB 0.00% of their portfolio STOCKHOLM, V7 28,31928.3k $3.7m $3.7m 0.00% Reduced -4.2k -4,180
92 Campbell & CO Investment Adviser LLC 0.17% of their portfolio BALTIMORE, MD 27,78327.8k $3.6m $3.6m 0.17% New
93 STOREBRAND ASSET MANAGEMENT AS 0.01% of their portfolio LYSAKER, Q8 27,71427.7k $3.6m $3.6m 0.01% Reduced -18 -18
94 CANADA LIFE ASSURANCE Co 0.01% of their portfolio WINNIPEG, A2 26,61026.6k $3.5m $3.5m 0.01% Reduced -510 -510
95 LOGAN CAPITAL MANAGEMENT INC 0.15% of their portfolio Newtown Square, PA 26,50526.5k $3.4m $3.4m 0.15% Added +1.4k +1,400
96 Onex Canada Asset Management Inc. 0.47% of their portfolio TORONTO, A6 25,80525.8k $3.4m $3.4m 0.47% Reduced -2.1k -2,118
97 INTECH INVESTMENT MANAGEMENT LLC 0.03% of their portfolio WEST PALM BEACH, FL 24,76524.8k $3.2m $3.2m 0.03% Reduced -4.9k -4,925
98 MetLife Investment Management, LLC 0.02% of their portfolio Whippany, NJ 24,47224.5k $3.2m $3.2m 0.02% Reduced -1.4k -1,377
99 Westmount Partners, LLC 0.79% of their portfolio LOS ANGELES, CA 24,23224.2k $3.2m $3.2m 0.79% Reduced -1.6k -1,634
100 NEW YORK STATE COMMON RETIREMENT FUND 0.00% of their portfolio ALBANY, NY 24,16024.2k $3.1m $3.1m 0.00% Unchanged