Statement of Changes in Beneficial Ownership (Form 4)

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b). Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person * Politan Capital Management LP 2. Issuer Name and Ticker or Trading Symbol MASIMO CORP [MASI] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner _____ Officer (give title below) __X__ Other (specify below) Director by deputization (Last) (First) (Middle) 106 WEST 56TH STREET, 10TH FLOOR 3. Date of Earliest Transaction (Month/Day/Year) 06/10/2026 (Street) NEW YORK, NY 10019 4. If Amendment, Date Original Filed (Month/Day/Year) 6. Individual or Joint/Group Filing (Check Applicable Line) ___ Form filed by One Reporting Person _X_ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Forward Sale Contract (obligation to sell)

(1)(2)

06/10/2026

J/K(1)(2)

142,681(1)(2)

(1)(2)

(1)(2)

Common Stock

142,681

(1)(2)

0

I

See footnotes(3)(4)(5)(6)(7)

Forward Sale Contract (obligation to sell)

(8)(9)

06/10/2026

J/K(8)(9)

130,869(8)(9)

(8)(9)

(8)(9)

Common Stock

130,869

(8)(9)

0

I

See footnotes(3)(4)(5)(6)(7)

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Politan Capital Management LP 106 WEST 56TH STREET 10TH FLOOR NEW YORK, NY 10019				Director by deputization
Politan Capital Management GP LLC 106 WEST 56TH STREET 10TH FLOOR NEW YORK, NY 10019				Director by deputization
Politan Capital Partners GP LLC 106 WEST 56TH STREET 10TH FLOOR NEW YORK, NY 10019				Director by deputization
Koffey Quentin 106 WEST 56TH STREET 10TH FLOOR NEW YORK, NY 10019				Director by deputization

Signatures

Politan Capital Management LP By: Politan Capital Management GP LLC, its General Partner /s/ Quentin Koffey, Managing Member		06/12/2026
**Signature of Reporting Person		Date
Politan Capital Management GP LLC /s/ Quentin Koffey, Managing Member		06/12/2026
**Signature of Reporting Person		Date
Politan Capital Partners GP LLC /s/ Quentin Koffey, Managing Member		06/12/2026
**Signature of Reporting Person		Date
/s/ Quentin Koffey		06/12/2026
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	On June 10, 2026, the March 11 Forward Contract (defined below) terminated in accordance with its terms. On March 11, 2026, Politan Capital Partners Master Fund LP, a Cayman Islands exempted limited partnership ("Politan Master Fund"), entered into a forward sale contract (the "March 11 Forward Contract") with a financial institution (the "Counterparty"). The March 11 Forward Contract obligated Politan Master Fund to deliver 142,681 common shares of MASI on the maturity date, August 12, 2026, subject to customary adjustments. Pursuant to the terms of the March 11 Forward Contract, the maturity date of the March 11 Forward Contract could have been extended one month to September 12, 2026, at the election of Politan Master Fund.
(2)	(continued from footnote 1) In exchange for entering into the March 11 Forward Contract, Politan Master Fund received an upfront payment of $24,802,095.85 on or around the trade date, which was based on a trade price of $175.48 per share. As a result of the Merger (defined below), pursuant to the terms of the March 11 Forward Contract, the March 11 Forward Contract terminated and Politan Master Fund paid the Counterparty $25,682,580.00, based on a price of $180.00 per share, as adjusted in accordance with the terms of the March 11 Forward Contract.
(3)	In addition to Politan Capital Management LP, a Delaware limited partnership ("Politan"), this Form 4 is being filed jointly by Politan Capital Management GP LLC, a Delaware limited liability company ("Politan Management"), Politan Capital Partners GP LLC, a Delaware limited liability company ("Politan GP"), and Quentin Koffey, a citizen of the United States of America (together with Politan, Politan Management and Politan GP, the "Reporting Persons"), each of whom has the same business address as Politan and may be deemed to have a pecuniary interest in securities reported on this Form 4 (the "Subject Securities").
(4)	Politan is the investment advisor to certain funds, including Politan Capital Partners LP, a Delaware limited partnership ("Politan LP"), Politan Capital Offshore Partners LP, a Cayman Islands exempted limited partnership ("Politan Offshore"), and Politan Master Fund (collectively with Politan Offshore and Politan LP, the "Politan Funds").
(5)	Politan, as the investment advisor of the Politan Funds, may be deemed to be the beneficial owner of the Subject Securities for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934. As the general partner of Politan, Politan Management may be deemed to be the beneficial owner of the Subject Securities for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934. As the general partner of the Politan Funds, Politan GP may be deemed to be the beneficial owner of the Subject Securities for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934.
(6)	By virtue of Mr. Koffey's position as managing partner and chief investment officer of Politan, and as the managing member of Politan Management and Politan GP, Mr. Koffey may be deemed to be the beneficial owner of the Subject Securities for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934. Each of the Reporting Persons disclaims any beneficial ownership of any of the Subject Securities, except to the extent of any pecuniary interest therein.
(7)	Mr. Koffey was a member of the board of directors of the Issuer of the Subject Securities, and as a result, each of the other Reporting Persons may be directors by deputization for purposes of Section 16 of the Securities Exchange Act of 1934.
(8)	On June 10, 2026, the March 12 Forward Contract (defined below) terminated in accordance with its terms. On March 12, 2026, Politan Master Fund, entered into a forward sale contract (the "March 12 Forward Contract") with the Counterparty. The March 12 Forward Contract obligated Politan Master Fund to deliver 130,869 common shares of MASI on the maturity date, August 13, 2026, subject to customary adjustments. Pursuant to the terms of the March 12 Forward Contract, the maturity date of the March 12 Forward Contract could have been extended one month to September 13, 2026, at the election of Politan Master Fund.
(9)	(continued from footnote 8) In exchange for entering into the March 12 Forward Contract, Politan Master Fund received an upfront payment of $22,749,606 on or around the trade date, which was based on a trade price of $175.48 per share. As a result of the Merger, pursuant to the terms of the March 12 Forward Contract, the March 12 Forward Contract terminated and Politan Master Fund paid the Counterparty $23,556,420.00, based on a price of $180.00 per share, as adjusted in accordance with the terms of the March 12 Forward Contract.
Remarks: On June 10, 2026, pursuant to the Agreement and Plan of Merger, dated as of February 16, 2026, by and among MASI, Danaher Corporation ("Parent") and Mobius Merger Sub, Inc. ("Merger Sub"), Merger Sub merged with and into the MASI (the "Merger"), with MASI continuing as the surviving corporation and a wholly owned subsidiary of Parent. At the effective time of the Merger, each common share of MASI issued and outstanding immediately prior to the effective time (other than certain excluded and dissenting shares) was canceled and converted into the right to receive $180.00 in cash, without interest.

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