Vault-13

MASIMO CORP MASI

COM · Common Stock · CUSIP 574795100 · ISIN US5747951003

380 institutional holders -14 vs Q1 2025
57,581,40157.6m shares reported held*
$9.7bnreported value*
41 new 125 added 138 reduced 57 sold out net bought ≈ $566.6m (+3.4m 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 ($7.2m this quarter). Holder counts are more reliable. Implied quarter-end price ≈ $168.22. Options: 5 managers hold calls ($10.1m notional), 4 hold puts ($3.9m).

Trends to Q2 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: 380380Q3 22Q2 23Q1 24Q4 24Q2 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

Buyers vs sellers

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

Bought or addedCut or sold out
4000400Q3 23: 139 bought or addedQ3 23: 276 cut or sold outQ4 23: 157 bought or addedQ4 23: 193 cut or sold outQ4 23Q1 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 25
Numbers
QuarterBought or addedCut or sold out
Q3 2023139276
Q4 2023157193
Q1 2024140177
Q2 2024170151
Q3 2024169170
Q4 2024162169
Q1 2025206161
Q2 2025166195

Calls vs puts

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

CallsPuts
$0$50m$100m$150mQ3 24 calls: $117.3mQ3 24 puts: $43.0mQ3 24P/C 0.37Q4 24 calls: $21.3mQ4 24 puts: $12.6mQ4 24P/C 0.59Q1 25 calls: $7.3mQ1 25 puts: $5.7mQ1 25P/C 0.78Q2 25 calls: $10.1mQ2 25 puts: $3.9mQ2 25P/C 0.38
Numbers
QuarterCallsPutsP/C
Q3 2024$117.3m$43.0m0.37
Q4 2024$21.3m$12.6m0.59
Q1 2025$7.3m$5.7m0.78
Q2 2025$10.1m$3.9m0.38

Biggest buyers

T. Rowe Price Investment Management, Inc. Added +826,892+826.9k
VIKING GLOBAL INVESTORS LP New +767,426+767.4k
BlackRock, Inc. Added +635,898+635.9k
WESTFIELD CAPITAL MANAGEMENT CO LP Added +509,724+509.7k
MASSACHUSETTS FINANCIAL SERVICES CO /MA/ Added +502,555+502.6k
Alyeska Investment Group, L.P. Added +411,956+412.0k
Grantham, Mayo, Van Otterloo & Co. LLC New +240,563+240.6k
GOLDMAN SACHS GROUP INC Added +191,270+191.3k
AMERIPRISE FINANCIAL INC Added +182,701+182.7k
ROYAL BANK OF CANADA Added +175,496+175.5k

Biggest sellers

Artisan Partners Limited Partnership Sold out -299,023-299.0k
Point72 Asset Management, L.P. Reduced -291,203-291.2k
Capital Research Global Investors Reduced -200,425-200.4k
DIMENSIONAL FUND ADVISORS LP Reduced -180,152-180.2k
MILLENNIUM MANAGEMENT LLC Reduced -130,899-130.9k
BANK OF AMERICA CORP /DE/ Reduced -126,467-126.5k
Verition Fund Management LLC Reduced -125,446-125.4k
FIL Ltd Reduced -113,462-113.5k
JPMORGAN CHASE & CO Reduced -108,399-108.4k
Holocene Advisors, LP Reduced -89,689-89.7k

Biggest calls

SUSQUEHANNA INTERNATIONAL GROUP, LLP Added $8.1m47.9k shares
CITADEL ADVISORS LLC Unchanged $1.3m7.7k shares
JANE STREET GROUP, LLC New $487.8k2.9k shares
SIMPLEX TRADING, LLC Reduced $235.0k1.4k shares
CONCOURSE FINANCIAL GROUP SECURITIES, INC. Unchanged $00 shares

Biggest puts

SUSQUEHANNA INTERNATIONAL GROUP, LLP Added $3.5m20.6k shares
CITADEL ADVISORS LLC Reduced $353.3k2.1k shares
SIMPLEX TRADING, LLC Reduced $50.0k300 shares
CONCOURSE FINANCIAL GROUP SECURITIES, INC. Unchanged $00 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, Q2 2025

#ManagerLocationShares Value% of their portfolioChangeShares change
1 BlackRock, Inc. 0.03% of their portfolio New York, NY 10,507,32610.5m $1.8bn $1.8bn 0.03% Added +635.9k +635,898
2 FMR LLC 0.08% of their portfolio BOSTON, MA 8,181,3728.2m $1.4bn $1.4bn 0.08% Added +2.6k +2,609
3 Politan Capital Management LP 56.98% of their portfolio NEW YORK, NY 4,716,5364.7m $793.4m $793.4m 56.98% Added +1.8k +1,790
4 VANGUARD GROUP INC 0.01% of their portfolio Valley Forge, PA 4,638,1354.6m $780.2m $780.2m 0.01% Added +54.9k +54,859
5 T. Rowe Price Investment Management, Inc. 0.27% of their portfolio BALTIMORE, MD 2,500,1442.5m $420.6m $420.6m 0.27% Added +826.9k +826,892
6 MASSACHUSETTS FINANCIAL SERVICES CO /MA/ 0.13% of their portfolio Boston, MA 2,470,3932.5m $415.6m $415.6m 0.13% Added +502.6k +502,555
7 Capital Research Global Investors 0.06% of their portfolio Los Angeles, CA 1,855,6701.9m $312.2m $312.2m 0.06% Reduced -200.4k -200,425
8 STATE STREET CORP 0.01% of their portfolio BOSTON, MA 1,486,3941.5m $250.0m $250.0m 0.01% Added +10.4k +10,403
9 Holocene Advisors, LP 0.52% of their portfolio New York, NY 1,243,6071.2m $209.2m $209.2m 0.52% Reduced -89.7k -89,689
10 WESTFIELD CAPITAL MANAGEMENT CO LP 0.83% of their portfolio BOSTON, MA 1,181,2031.2m $198.7m $198.7m 0.83% Added +509.7k +509,724
11 Durable Capital Partners LP 1.48% of their portfolio Bethesda, MD 1,163,8981.2m $195.8m $195.8m 1.48% Added +38.3k +38,279
12 Alyeska Investment Group, L.P. 0.68% of their portfolio CHICAGO, IL 1,134,4901.1m $190.8m $190.8m 0.68% Added +412.0k +411,956
13 GEODE CAPITAL MANAGEMENT, LLC 0.01% of their portfolio BOSTON, MA 896,418896.4k $150.8m $150.8m 0.01% Added +52.1k +52,100
14 ALLIANCEBERNSTEIN L.P. 0.05% of their portfolio NASHVILLE, TN 844,067844.1k $142.0m $142.0m 0.05% Reduced -21.8k -21,803
15 VIKING GLOBAL INVESTORS LP 0.37% of their portfolio STAMFORD, CT 767,426767.4k $129.1m $129.1m 0.37% New
16 MORGAN STANLEY 0.01% of their portfolio NEW YORK, NY 767,375767.4k $129.1m $129.1m 0.01% Added +31.6k +31,593
17 Liontrust Investment Partners LLP 1.71% of their portfolio LONDON, X0 708,300708.3k $119.2m $119.2m 1.71% Reduced -39.2k -39,198
18 RTW INVESTMENTS, LP 1.64% of their portfolio NEW YORK, NY 683,294683.3k $114.9m $114.9m 1.64% Unchanged
19 DIMENSIONAL FUND ADVISORS LP 0.02% of their portfolio AUSTIN, TX 523,226523.2k $88.0m $88.0m 0.02% Reduced -180.2k -180,152
20 GOLDMAN SACHS GROUP INC 0.01% of their portfolio NEW YORK, NY 471,525471.5k $79.3m $79.3m 0.01% Added +191.3k +191,270
21 Sumitomo Mitsui Trust Group, Inc. 0.05% of their portfolio CHIYODA-KU, TOKYO, M0 471,041471.0k $79.2m $79.2m 0.05% Added +98.1k +98,063
22 SCHRODER INVESTMENT MANAGEMENT GROUP 0.06% of their portfolio London, X0 448,501448.5k $75.4m $75.4m 0.06% Added +13.0k +12,953
23 PRICE T ROWE ASSOCIATES INC /MD/ 0.01% of their portfolio BALTIMORE, MD 405,460405.5k $68.2m $68.2m 0.01% Added +122.8k +122,823
24 AMERIPRISE FINANCIAL INC 0.02% of their portfolio MINNEAPOLIS, MN 394,487394.5k $66.4m $66.4m 0.02% Added +182.7k +182,701
25 NORTHERN TRUST CORP 0.01% of their portfolio CHICAGO, IL 388,542388.5k $65.4m $65.4m 0.01% Added +5.2k +5,186
26 BAMCO INC /NY/ 0.18% of their portfolio NEW YORK, NY 384,589384.6k $64.7m $64.7m 0.18% Added +67.3k +67,307
27 CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.01% of their portfolio SAN FRANCISCO, CA 370,734370.7k $62.4m $62.4m 0.01% Reduced -6.3k -6,336
28 Corient Private Wealth LP 0.07% of their portfolio MIAMI, FL 330,414330.4k $55.6m $55.6m 0.07% Reduced -17.6k -17,624
29 Bank of New York Mellon Corp 0.01% of their portfolio NEW YORK, NY 317,593317.6k $53.4m $53.4m 0.01% Reduced -14.5k -14,515
30 Grantham, Mayo, Van Otterloo & Co. LLC 0.12% of their portfolio Boston, MA 240,563240.6k $40.5m $40.5m 0.12% New
31 Invesco Ltd. 0.01% of their portfolio ATLANTA, GA 237,303237.3k $39.9m $39.9m 0.01% Reduced -24.1k -24,055
32 ROYAL BANK OF CANADA 0.00% of their portfolio TORONTO, A6 219,380219.4k $36.9m $36.9m 0.00% Added +175.5k +175,496
33 UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.01% of their portfolio NEW YORK, NY 209,563209.6k $35.3m $35.3m 0.01% Added +20.4k +20,433
34 RAYMOND JAMES FINANCIAL INC 0.01% of their portfolio ST. PETERSBURG, FL 200,229200.2k $33.7m $33.7m 0.01% Reduced -5.9k -5,887
35 BANK OF AMERICA CORP /DE/ 0.00% of their portfolio CHARLOTTE, NC 190,176190.2k $32.0m $32.0m 0.00% Reduced -126.5k -126,467
36 COMERICA BANK 0.12% of their portfolio DALLAS, TX 189,822189.8k $31.9m $31.9m 0.12% Added +52.0k +51,967
37 Woodline Partners LP 0.16% of their portfolio San Francisco, CA 182,709182.7k $30.7m $30.7m 0.16% Added +49.7k +49,740
38 TD Asset Management Inc 0.02% of their portfolio Toronto, A6 167,176167.2k $28.1m $28.1m 0.02% Added +78.5k +78,508
39 Gotham Asset Management, LLC 0.17% of their portfolio NEW YORK, NY 165,356165.4k $27.8m $27.8m 0.17% Added +20.8k +20,766
40 AMERICAN CENTURY COMPANIES INC 0.01% of their portfolio KANSAS CITY, MO 152,228152.2k $25.6m $25.6m 0.01% Added +73.1k +73,052
41 Nuveen, LLC 0.01% of their portfolio CHARLOTTE, NC 149,658149.7k $25.2m $25.2m 0.01% Reduced -5.4k -5,387
42 HAWK RIDGE CAPITAL MANAGEMENT LP 1.04% of their portfolio LOS ANGELES, CA 148,685148.7k $25.0m $25.0m 1.04% New
43 UBS Group AG 0.00% of their portfolio ZURICH, V8 142,164142.2k $23.9m $23.9m 0.00% Reduced -28.0k -28,013
44 JPMORGAN CHASE & CO 0.00% of their portfolio NEW YORK, NY 138,090138.1k $23.2m $23.2m 0.00% Reduced -108.4k -108,399
45 RHUMBLINE ADVISERS 0.02% of their portfolio BOSTON, MA 127,496127.5k $21.4m $21.4m 0.02% Added +4.7k +4,685
46 Quantinno Capital Management LP 0.09% of their portfolio NEW YORK, NY 120,383120.4k $20.3m $20.3m 0.09% Added +56.6k +56,644
47 Rockefeller Capital Management L.P. 0.02% of their portfolio NEW YORK, NY 115,626115.6k $19.5m $19.5m 0.02% Reduced -1.7k -1,700
48 Tidal Investments LLC 0.12% of their portfolio Milwaukee, WI 106,198106.2k $17.9m $17.9m 0.12% Reduced -4.3k -4,288
49 Legal & General Group Plc 0.00% of their portfolio London, X0 104,364104.4k $17.6m $17.6m 0.00% Added +4.8k +4,822
50 PRINCIPAL FINANCIAL GROUP INC 0.01% of their portfolio DES MOINES, IA 102,467102.5k $17.2m $17.2m 0.01% Reduced -194 -194
51 Alpha Wave Global, LP 1.85% of their portfolio Miami, FL 102,068102.1k $17.2m $17.2m 1.85% New
52 FIRST TRUST ADVISORS LP 0.01% of their portfolio Wheaton, IL 99,61299.6k $16.8m $16.8m 0.01% Reduced -45.6k -45,552
53 CRAMER ROSENTHAL MCGLYNN LLC 1.10% of their portfolio STAMFORD, CT 94,93994.9k $16.0m $16.0m 1.10% Reduced -56.7k -56,725
54 PFM Health Sciences, LP 1.38% of their portfolio SAN FRANCISCO, CA 94,45194.5k $15.9m $15.9m 1.38% New
55 Erste Asset Management GmbH 0.13% of their portfolio VIENNA, C4 92,00092.0k $15.5m $15.5m 0.13% Unchanged
56 Bellevue Group AG 0.33% of their portfolio ZURICH, V8 89,67389.7k $15.1m $15.1m 0.33% Added +19.9k +19,865
57 Swiss National Bank 0.01% of their portfolio ZURICH, V8 87,70087.7k $14.8m $14.8m 0.01% Reduced -500 -500
58 BLI - Banque de Luxembourg Investments 0.42% of their portfolio LUXEMBOURG CITY, N4 86,70086.7k $14.6m $14.6m 0.42% Reduced -14.5k -14,500
59 GAMCO INVESTORS, INC. ET AL 0.14% of their portfolio GREENWICH, CT 84,50084.5k $14.2m $14.2m 0.14% Unchanged
60 GREAT LAKES ADVISORS, LLC 0.12% of their portfolio CHICAGO, IL 82,34882.3k $13.9m $13.9m 0.12% Reduced -10.5k -10,524
61 Squarepoint Ops LLC 0.03% of their portfolio NEW YORK, NY 74,02774.0k $12.5m $12.5m 0.03% Added +57.4k +57,359
62 Swedbank AB 0.01% of their portfolio STOCKHOLM, V7 73,80073.8k $12.4m $12.4m 0.01% First filing
63 California Public Employees Retirement System 0.01% of their portfolio Sacramento, CA 72,80772.8k $12.2m $12.2m 0.01% Added +2.9k +2,932
64 Point72 (DIFC) Ltd 0.92% of their portfolio DUBAI, C0 68,70068.7k $11.6m $11.6m 0.92% Added +27.1k +27,061
65 BNP PARIBAS ASSET MANAGEMENT Holding S.A. 0.03% of their portfolio Paris, I0 65,82165.8k $11.1m $11.1m 0.03% New
66 MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.01% of their portfolio Toronto, A6 58,71458.7k $9.9m $9.9m 0.01% Added +4.8k +4,814
67 FIL Ltd 0.01% of their portfolio HAMILTON, D0 56,32656.3k $9.5m $9.5m 0.01% Reduced -113.5k -113,462
68 BARCLAYS PLC 0.00% of their portfolio LONDON, X0 56,11456.1k $9.4m $9.4m 0.00% Added +16.3k +16,261
69 STRS OHIO 0.04% of their portfolio COLUMBUS, OH 55,98356.0k $9.4m $9.4m 0.04% Added +15.8k +15,848
70 Retirement Systems of Alabama 0.03% of their portfolio MONTGOMERY, AL 55,00355.0k $9.3m $9.3m 0.03% Added +916 +916
71 BANK OF NOVA SCOTIA 0.02% of their portfolio TORONTO, A6 53,10853.1k $8.9m $8.9m 0.02% Reduced -40.1k -40,095
72 AQR CAPITAL MANAGEMENT LLC 0.01% of their portfolio Greenwich, CT 50,25650.3k $8.5m $8.5m 0.01% Added +42.1k +42,114
73 CITIGROUP INC 0.01% of their portfolio NEW YORK, NY 49,96250.0k $8.4m $8.4m 0.01% Reduced -2.2k -2,196
74 Cinctive Capital Management LP 0.44% of their portfolio New York, NY 46,78746.8k $7.9m $7.9m 0.44% New
75 NATIXIS 0.04% of their portfolio PARIS, I0 45,64845.6k $7.7m $7.7m 0.04% New
76 4D Advisors, LLC 4.07% of their portfolio REDONDO BEACH, CA 45,00045.0k $7.6m $7.6m 4.07% Added +15.0k +15,000
77 PICTON MAHONEY ASSET MANAGEMENT 0.11% of their portfolio Toronto, A6 44,55744.6k $7.5m $7.5m 0.11% Added +405 +405
78 CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.01% of their portfolio WEST SACRAMENTO, CA 43,35343.4k $7.3m $7.3m 0.01% Added +101 +101
79 STATE BOARD OF ADMINISTRATION OF FLORIDA RETIREMENT SYSTEM 0.01% of their portfolio TALLAHASSEE, FL 43,31943.3k $7.3m $7.3m 0.01% Added +548 +548
80 Walleye Capital LLC 0.07% of their portfolio NEW YORK, NY 43,23243.2k $7.3m $7.3m 0.07% Reduced -33.1k -33,138
81 NS Partners Ltd 0.29% of their portfolio LONDON, X0 42,56642.6k $7.2m $7.2m 0.29% Reduced -989 -989
82 Amundi 0.00% of their portfolio Paris, I0 41,58341.6k $7.1m $7.1m 0.00% Added +416 +416
83 Baird Financial Group, Inc. 0.01% of their portfolio MILWAUKEE, WI 40,72040.7k $6.8m $6.8m 0.01% Reduced -4.4k -4,400
84 NEW YORK STATE TEACHERS RETIREMENT SYSTEM 0.01% of their portfolio ALBANY, NY 40,04840.0k $6.7m $6.7m 0.01% Unchanged
85 NORGES BANK 0.00% of their portfolio OSLO, Q8 39,05339.1k $6.6m $6.6m 0.00% Reduced -361 -361
86 BRIDGER MANAGEMENT, LLC 3.34% of their portfolio NEW YORK, NY 33,64133.6k $5.7m $5.7m 3.34% Reduced -5.7k -5,659
87 GABELLI FUNDS LLC 0.04% of their portfolio Rye, NY 32,70032.7k $5.5m $5.5m 0.04% Reduced -300 -300
88 NORDEA INVESTMENT MANAGEMENT AB 0.00% of their portfolio STOCKHOLM, V7 31,86831.9k $5.3m $5.3m 0.00% Added +5.7k +5,659
89 INTECH INVESTMENT MANAGEMENT LLC 0.05% of their portfolio WEST PALM BEACH, FL 31,75031.8k $5.3m $5.3m 0.05% Reduced -744 -744
90 LOGAN CAPITAL MANAGEMENT INC 0.25% of their portfolio Newtown Square, PA 31,35231.4k $5.3m $5.3m 0.25% Reduced -11.0k -11,043
91 SEI INVESTMENTS CO 0.01% of their portfolio OAKS, PA 30,50630.5k $5.1m $5.1m 0.01% Reduced -18.9k -18,859
92 VICTORY CAPITAL MANAGEMENT INC 0.00% of their portfolio San Antonio, TX 29,36829.4k $4.9m $4.9m 0.00% Added +3.0k +3,001
93 ENVESTNET ASSET MANAGEMENT INC 0.00% of their portfolio Berwyn, PA 27,23427.2k $4.6m $4.6m 0.00% Reduced -4.6k -4,554
94 WILSON ASSET MANAGEMENT (INTERNATIONAL) PTY LTD 1.13% of their portfolio SYDNEY, C3 27,23427.2k $4.6m $4.6m 1.13% New
95 HARBOR CAPITAL ADVISORS, INC. 0.19% of their portfolio CHICAGO, IL 26,41226.4k $4.4m $4.4m 0.19% New
96 MetLife Investment Management, LLC 0.03% of their portfolio Whippany, NJ 26,28526.3k $4.4m $4.4m 0.03% Added +645 +645
97 CANADA LIFE ASSURANCE Co 0.01% of their portfolio WINNIPEG, A2 26,12026.1k $4.4m $4.4m 0.01% Reduced -492 -492
98 Westmount Partners, LLC 1.19% of their portfolio LOS ANGELES, CA 25,86625.9k $4.4m $4.4m 1.19% Reduced -125 -125
99 RENAISSANCE TECHNOLOGIES LLC 0.01% of their portfolio NEW YORK, NY 25,37725.4k $4.3m $4.3m 0.01% Added +10.4k +10,377
100 South Dakota Investment Council 0.08% of their portfolio SIOUX FALLS, SD 24,76824.8k $4.2m $4.2m 0.08% Unchanged