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Masimo Corp

MASIDelisted Jun 10, 2026
Industry
Electromedical & Electrotherapeutic Apparatus
SEC CIK
0000937556

Masimo Corp was delisted on Jun 10, 2026; its insiders filed their last Form 4 on Jun 12, 2026; 453 institutions reported holding it in 13F filings for Q1 2026, worth $9.69B in total; Soros Fund Management was the only superinvestor holding it.

Holders of 5% or more of MASI

Holders whose latest Schedule 13D or 13G filing reports 5% or more of Masimo Corp, largest stake first. The change is against the holder's previous filing.

Holders of 5% or more of MASI
HolderLatest formStakeChangeFirst filedLatest filingFiling
BlackRock, Inc.13G/A7.90%4.23M shares–Feb 7, 20251 filingFeb 7, 2025SEC
Kiani Joe E13G/A6.50%3.66M shares−3.80 ppfrom 10.30%Feb 12, 20219 filingsMay 14, 2026SEC
Barclays PLC13G5.54%2.89M sharesNewMay 14, 20261 filingMay 14, 2026SEC

Stakes are as of each holder's latest filing. Holders whose last filing was in the old format (before December 18, 2024) have no stake on record and are not listed, and after an acquisition or delisting holders usually stop filing.

13D and 13G filings

53 Schedule 13D and 13G filings on Masimo Corp, newest first, including old-format filings without a stake.

Schedule 13D and 13G filings on MASI
Filed (ET)FilerFormStakeChangeEvent dateFiling
Aug 14, 20264:23 PM ETPentwater Capital Management LPand 1 other13G/A0.00%0 shares−6.10 ppfrom 6.10%Below 5%Jun 30, 2026SEC
Jun 11, 20269:39 PM ETPolitan Capital Management LPand 3 others13D/A0.00%0 shares−6.20 ppfrom 6.20%Below 5%Jun 10, 2026SEC
May 15, 20264:33 PM ETPentwater Capital Management LPand 1 other13G6.10%3.18M sharesNewMar 31, 2026SEC
May 14, 20269:28 PM ETBarclays PLC13G5.54%2.89M sharesNewMar 31, 2026SEC
May 14, 20265:00 PM ETKiani Joe E13G/A6.50%3.66M shares−3.80 ppfrom 10.30%Mar 31, 2026SEC
Apr 30, 20264:37 PM ETBlackRock Portfolio Management LLC13G/A0.20%116.9K shares−8.00 ppfrom 8.20%Below 5%Mar 31, 2026SEC
Mar 27, 202610:33 AM ETVanguard Group Inc13G/A0.00%0 shares–Below 5%Mar 13, 2026SEC
Mar 6, 202610:05 AM ETFMR LLCand 1 other13G/A4.50%2.35M shares−10.50 ppfrom 15.00%Below 5%Feb 27, 2026SEC
Feb 17, 20269:45 PM ETPolitan Capital Management LPand 3 others13D/A6.20%4.59M shares–Feb 16, 2026SEC
Feb 13, 20267:59 PM ETKiani Joe E13G/A10.30%5.90M shares−0.80 ppfrom 11.10%Dec 31, 2025SEC
Jan 21, 202612:26 PM ETBlackRock Portfolio Management LLC13G/A8.20%4.39M shares−2.10 ppfrom 10.30%Dec 31, 2025SEC
Nov 12, 20258:00 PM ETKiani Joe E13G/A11.10%6.38M shares−0.30 ppfrom 11.40%Sep 30, 2025SEC
Aug 12, 20257:00 PM ETKiani Joe E13G/A11.40%6.58M shares−1.80 ppfrom 13.20%Jun 30, 2025SEC
Apr 22, 20258:01 PM ETKiani Joe E13G/A13.20%7.62M shares–Mar 31, 2025SEC
Mar 4, 202512:39 PM ETBlackRock Portfolio Management LLC13G10.30%5.54M sharesNewFeb 28, 2025SEC
Feb 12, 20259:30 AM ETFMR LLCand 1 other13G/A15.00%8.03M shares–Dec 31, 2024SEC
Feb 7, 20251:50 PM ETBlackRock, Inc.13G/A7.90%4.23M shares–Jan 31, 2025SEC
Sep 25, 2024Politan Capital Management LP13D/AOld format–––SEC
Aug 30, 2024Politan Capital Management LP13D/AOld format–––SEC
Jul 17, 2024Politan Capital Management LP13D/AOld format–––SEC
Jul 15, 2024Politan Capital Management LP13D/AOld format–––SEC
Jul 12, 2024Politan Capital Management LP13D/AOld format–––SEC
Jul 8, 2024Politan Capital Management LP13D/AOld format–––SEC
Jun 7, 20241:30 PM ETBlackRock Inc.13G/AOld format–––SEC
May 9, 2024Politan Capital Management LP13D/AOld format–––SEC
May 8, 2024Politan Capital Management LP13D/AOld format–––SEC
Mar 27, 2024Politan Capital Management LP13D/AOld format–––SEC
Feb 14, 2024Kiani Joe E13G/AOld format–––SEC
Feb 13, 2024Vanguard Group Inc13G/AOld format–––SEC
Feb 9, 2024FMR LLC13G/AOld format–––SEC
Jan 24, 20249:46 AM ETBlackRock Inc.13G/AOld format–––SEC
Jun 30, 2023Politan Capital Management LP13D/AOld format–––SEC
May 1, 2023Politan Capital Management LP13D/AOld format–––SEC
Mar 13, 2023Politan Capital Management LP13D/AOld format–––SEC
Mar 6, 2023Politan Capital Management LP13D/AOld format–––SEC
Feb 14, 2023Kiani Joe E13G/AOld format–––SEC
Feb 9, 2023Vanguard Group Inc13G/AOld format–––SEC
Jan 26, 20238:52 AM ETBlackRock Inc.13G/AOld format–––SEC
Jan 20, 20235:17 PM ETBlackRock Inc.13G/AOld format–––SEC
Jan 10, 2023FMR LLC13GOld format–––SEC
Oct 21, 2022Politan Capital Management LP13D/AOld format–––SEC
Sep 27, 2022Politan Capital Management LP13D/AOld format–––SEC
Aug 16, 2022Politan Capital Management LP13DOld format–New–SEC
Jun 9, 20223:20 PM ETBlackRock Inc.13GOld format–––SEC
Feb 14, 2022Kiani Joe E13G/AOld format–––SEC
Feb 10, 2022Vanguard Group Inc13G/AOld format–––SEC
Feb 9, 2022FMR LLC13G/AOld format–––SEC
Jan 27, 20221:59 PM ETBlackRock Inc.13G/AOld format–––SEC
Jan 25, 20226:45 PM ETBlackRock Inc.13GOld format–––SEC
Feb 12, 2021Kiani Joe E13G/AOld format–––SEC

Form 144: proposed insider sales

17 notices from officers, directors and other affiliates planning to sell Masimo Corp shares, newest first.

Form 144 notices for MASI
Filed (ET)SellerShares to sellMarket valuePlanned saleBrokerFiling
Jan 28, 20264:00 PM ETSampath AnandOfficer18.7K$2.56MJan 28, 202610b5-1Charles Schwab & Co., Inc.SEC
Dec 11, 20254:07 PM ETTripodi BlairFormer affiliate17.1K$2.43MDec 11, 2025Charles Schwab & Co., Inc.SEC
Nov 28, 20251:43 PM ETAhmed OmarOfficer3.23K$461.1KNov 28, 202510b5-1Charles Schwab & Co., Inc.SEC
Sep 29, 20254:46 PM ETMuhsin BilalFormer affiliate25.1K$3.55MSep 29, 2025Charles Schwab & Co., Inc.SEC
Sep 26, 20254:05 PM ETMuhsin BilalFormer affiliate50.0K$7.09MSep 26, 2025Charles Schwab & Co., Inc.SEC
Sep 23, 20254:57 PM ETMuhsin BilalFormer affiliate25.0K$3.52MSep 23, 2025Charles Schwab & Co., Inc.SEC
May 13, 20254:44 PM ETReynolds Craig BFormer director16.4K$2.70MMay 13, 2025Charles Schwab & Co., Inc.SEC
May 12, 20254:39 PM ETMuhsin BilalOfficer10.0K$1.63MMay 12, 202510b5-1Charles Schwab & Co., Inc.SEC
May 12, 20254:38 PM ETChapek Robert AFormer affiliate3.46K$564.6KMay 12, 2025Charles Schwab & Co., Inc.SEC
Apr 24, 20254:20 PM ETMcClenahan Thomas SamuelFormer officer26.3K$4.29MApr 24, 2025Charles Schwab & Co., Inc.SEC
Mar 14, 20254:10 PM ETReynolds Craig BDirector2.05K$341.1KMar 14, 2025Charles Schwab & Co., Inc.SEC
Mar 10, 20255:12 PM ETMuhsin BilalOfficer30.0K$5.02MMar 10, 2025Charles Schwab & Co., Inc.SEC
Mar 3, 20254:44 PM ETMcClenahan Thomas SamuelOfficer49.0K$9.37MMar 3, 2025Charles Schwab & Co., Inc.SEC
Mar 3, 20251:26 PM ETLevy TaoFormer affiliate36.5K$6.86MFeb 28, 2025Charles Schwab & Co., Inc.SEC
Jan 7, 20255:36 PM ETKiani Joe EFormer affiliate302.2K$50.1MJan 7, 2025Charles Schwab & Co., Inc.SEC
Dec 16, 20244:09 PM ETLevy TaoFormer affiliate15.1K$2.66MDec 16, 2024Charles Schwab & Co., Inc.SEC
Apr 26, 20245:22 PM ETReynolds Craig BDirector40.0K$5.45MApr 26, 202410b5-1Charles Schwab & Co., Inc.SEC