Masimo (MASI) grants 5,985 restricted stock units to Chief HR Officer

Rhea-AI Filing Summary

Hellmann Elisabeth A reported acquisition or exercise transactions in this Form 4 filing.

MASIMO CORP reported that Chief Human Resources Officer Elisabeth A. Hellmann received a grant of 5,985 restricted stock units on March 6, 2026. Each unit represents the right to receive one share of Masimo common stock upon vesting. The award vests in four equal annual installments of 25% on each anniversary of the grant date, aligning her compensation with longer-term company performance. Following this grant, she holds 5,985 restricted stock units directly.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Hellmann Elisabeth A

Role Chief Human Resources Officer

Type	Security	Shares	Price	Value
Grant/Award	Restricted Stock Units	5,985	$0.00	--

Holdings After Transaction: Restricted Stock Units — 5,985 shares (Direct)

Footnotes (1)

1. Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of the Issuer upon vesting of the RSU. This RSU award was granted on March 6, 2026 and will vest ratably over four years, with 25% of the award vesting on each anniversary of the grant date.

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
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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^*

Hellmann Elisabeth A

(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)
	Chief Human Resources Officer

3. Date of Earliest Transaction (Month/Day/Year)
03/06/2026

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

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	(1)	03/06/2026		A		5,985		(2)	03/06/2036	Common Stock	5,985	$0	5,985	D

Explanation of Responses:

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

2. This RSU award was granted on March 6, 2026 and will vest ratably over four years, with 25% of the award vesting on each anniversary of the grant date.

Remarks:

	/s/ Micah W. Young, Attorney-In-Fact	03/10/2026
	** 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.

FAQ

What insider transaction did MASIMO CORP (MASI) report for Elisabeth A. Hellmann?

MASIMO CORP reported that Chief Human Resources Officer Elisabeth A. Hellmann received 5,985 restricted stock units on March 6, 2026. These units are a stock-based compensation award that converts into common shares as they vest over time.

How many restricted stock units were granted to the MASI Chief Human Resources Officer?

Elisabeth A. Hellmann was granted 5,985 restricted stock units. Each unit represents the contingent right to receive one Masimo common share upon vesting, providing equity-based compensation that links her potential future value directly to the company’s stock performance.

What is the vesting schedule for the MASIMO CORP (MASI) restricted stock units granted on March 6, 2026?

The 5,985 restricted stock units granted on March 6, 2026 vest ratably over four years. Twenty-five percent of the award vests on each anniversary of the grant date, encouraging multi-year retention and alignment with the company’s longer-term operational and strategic goals.

Does the MASIMO CORP (MASI) Form 4 involve a stock purchase or sale by the insider?

The Form 4 reflects an acquisition of 5,985 restricted stock units as a grant, not an open-market stock purchase or sale. It is categorized as a grant, award, or other acquisition of derivative securities, with no purchase price paid per unit.

What does each MASIMO CORP (MASI) restricted stock unit represent for the CHRO?

Each restricted stock unit represents the contingent right to receive one share of Masimo common stock when it vests. The value ultimately realized depends on the company’s share price at vesting and the units continuing to meet the vesting conditions over four years.

How many MASIMO CORP (MASI) restricted stock units does Elisabeth A. Hellmann hold after this transaction?

After the reported grant, Elisabeth A. Hellmann holds 5,985 restricted stock units directly. These units are scheduled to vest in four equal annual installments, with an expiration date in 2036 if they have not been settled into common shares earlier through vesting.