Masimo (MASI) CFO Micah Young logs 15,000 RSU vesting and tax share withholding

Rhea-AI Filing Summary

Masimo Corp EVP & Chief Financial Officer Micah W. Young reported the vesting of 15,000 restricted stock units and related share movements. The vested RSUs converted into 15,000 shares of common stock, with 8,093 shares withheld at $175.35 per share to cover tax obligations, resulting in 6,907 shares delivered. Following these transactions, Young directly owns 25,254 shares of Masimo common stock. These events reflect equity compensation vesting and tax withholding, not open-market buying or selling.

Insider Trade Summary

15,000 shares exercised/converted

Mixed 3 txns

Insider Young Micah W

Role EVP & Chief Financial Officer

Type	Security	Shares	Price	Value
Exercise	Restricted Stock Units	15,000	$0.00	--
Grant/Award	Common Stock	15,000	$0.00	--
Tax Withholding	Common Stock	8,093	$175.35	$1.42M

Holdings After Transaction: Restricted Stock Units — 0 shares (Direct); Common Stock — 33,347 shares (Direct)

Footnotes (1)

1. As previously reported, the reporting person was granted 30,000 restricted stock units on March 1, 2024, 50% of which vested on March 1, 2025. The remaining 15,000 restricted stock units vested on February 27, 2026. For the vesting that occurred on March 1, 2026, the Issuer calculated the number of vested shares and shares withheld for tax liability based on its closing stock price on the immediately preceding business day. As a result, the Reporting person received 6,907 shares of common stock, as shown in Table I. These shares were withheld by the Issuer in order to satisfy certain tax withholding obligations in connection with the issuance of shares upon the vesting of certain restricted stock units. Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of the Issuer upon vesting of the RSU.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

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 for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Young Micah W

(Last) (First) (Middle)

C/O MASIMO CORPORATION

52 DISCOVERY

(Street)

IRVINE CA 92618

(City) (State) (Zip)

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
X	Officer (give title below)		Other (specify below)
	EVP & Chief Financial Officer

3. Date of Earliest Transaction (Month/Day/Year)
02/27/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

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
Common Stock	02/27/2026		A		15,000(1)(2)	A	$0	33,347	D
Common Stock	02/27/2026		F		8,093(3)	D	$175.35	25,254	D

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 Securities Underlying Derivative Security (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: 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
Restricted Stock Units	(4)	02/27/2026		M			15,000	(1)	(1)	Common Stock	15,000	$0	0	D

Explanation of Responses:

1. As previously reported, the reporting person was granted 30,000 restricted stock units on March 1, 2024, 50% of which vested on March 1, 2025. The remaining 15,000 restricted stock units vested on February 27, 2026.

2. For the vesting that occurred on March 1, 2026, the Issuer calculated the number of vested shares and shares withheld for tax liability based on its closing stock price on the immediately preceding business day. As a result, the Reporting person received 6,907 shares of common stock, as shown in Table I.

3. These shares were withheld by the Issuer in order to satisfy certain tax withholding obligations in connection with the issuance of shares upon the vesting of certain restricted stock units.

4. Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of the Issuer upon vesting of the RSU.

Remarks:

	/s/ Micah W. Young, Attorney-In-Fact	03/03/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.