Masimo Corporation
US ˙ NasdaqGS ˙ US5747951003

SecurityMASI / Masimo Corporation
InstitutionEngineers Gate Manager LP
Latest Disclosed Ownership30,423 shares
Latest Disclosed Value $ 5,411,340
Engineers Gate Manager LP reports 63.55% decrease in ownership of MASI / Masimo Corporation

On May 15, 2026 - Engineers Gate Manager LP filed a 13F-HR form disclosing ownership of 30,423 shares of Masimo Corporation (US:MASI) valued at $5,411,339 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 83,458 shares of Masimo Corporation. This represents a change in shares of -63.55% during the quarter. The current value of the position is $5,439,024 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F MASIMO COM 574795100 30,423 -53,035 -63.55 5,411 -50.15 0.0676
2026-02-17 2025-12-31 13F MASIMO COM 574795100 83,458 52,685 171.21 10,855 139.07 0.1287
2025-11-14 2025-09-30 13F MASIMO COM 574795100 30,773 23,900 347.74 4,541 292.73 0.0520
2025-08-14 2025-06-30 13F MASIMO COM 574795100 6,873 -881 -11.36 1,156 -10.46 0.0144
2025-05-15 2025-03-31 13F MASIMO COM 574795100 7,754 7,754 1,292 0.0218
2025-02-14 2024-12-31 13F MASIMO COM 574795100 0 -9,980 -100.00 0 -100.00
2024-11-14 2024-09-30 13F MASIMO COM 574795100 9,980 -1,094 -9.88 1,331 -4.59 0.0260
2024-08-14 2024-06-30 13F MASIMO COM 574795100 11,074 11,074 1,395 0.0315
2024-02-14 2023-12-31 13F MASIMO COM 574795100 0 -12,491 -100.00 0 -100.00
2023-11-14 2023-09-30 13F MASIMO COM 574795100 12,491 11,164 841.30 1,095 402.29 0.0405
2023-08-14 2023-06-30 13F MASIMO COM 574795100 1,327 1,327 218 0.0083
2022-11-14 2022-09-30 13F MASIMO COM 574795100 0 -5,104 -100.00 0 -100.00
2022-08-15 2022-06-30 13F MASIMO COM 574795100 5,104 -33,311 -86.71 667 -88.07 0.0244
2022-05-16 2022-03-31 13F MASIMO COM 574795100 38,415 38,415 5,591 0.2188
2021-11-15 2021-09-30 13F MASIMO COM 574795100 0 -1,303 -100.00 0 -100.00
2021-08-16 2021-06-30 13F MASIMO COM 574795100 1,303 -8,412 -86.59 316 -85.84 0.0203
2021-05-17 2021-03-31 13F MASIMO COM 574795100 9,715 8,640 803.72 2,231 671.97 0.1105
2021-02-16 2020-12-31 13F MASIMO COM 574795100 1,075 1,075 289 0.0125
2020-11-16 2020-09-30 13F MASIMO COM 574795100 0 -7,903 -100.00 0 -100.00
2020-08-17 2020-06-30 13F MASIMO COM 574795100 7,903 6,320 399.24 1,802 543.57 0.0917
2020-05-15 2020-03-31 13F MASIMO COM 574795100 1,583 221 16.23 280 30.23 0.0202
2020-02-14 2019-12-31 13F MASIMO COM 574795100 1,362 1,362 215 0.0095
2019-11-14 2019-09-30 13F MASIMO COM 574795100 0 -3,860 -100.00 0 -100.00
2019-08-14 2019-06-30 13F MASIMO COM 574795100 3,860 3,860 575 0.0317
2019-05-15 2019-03-31 13F MASIMO COM 574795100 0 -23,568 -100.00 0 -100.00
2019-02-14 2018-12-31 13F MASIMO COM 574795100 23,568 23,568 2,530 0.2025
2017-08-10 2017-06-30 13F MASIMO COM 574795100 0 -45,436 -100.00 0 -100.00
2017-05-05 2017-03-31 13F MASIMO COM 574795100 45,436 45,436 4,237 0.4207
2016-05-09 2016-03-31 13F MASIMO COM 574795100 0 -37,082 -100.00 0 -100.00
2016-02-05 2015-12-31 13F MASIMO COM 574795100 37,082 -9,492 -20.38 1,539 -14.31 0.1039
2015-11-16 2015-09-30 13F MASIMO COM 574795100 46,574 46,574 1,796 0.1529
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.