Statement of Changes in Beneficial Ownership (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).

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

OMB APPROVAL

OMB Number:

3235-0287

Estimated average burden
hours per response...

0.5

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

1. Name and Address of Reporting Person * Young Micah W	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
(Last)          (First)          (Middle) C/O MASIMO CORPORATION, 52 DISCOVERY	3. Date of Earliest Transaction (MM/DD/YYYY) 4/15/2020
(Street) IRVINE, CA 92618 (City)        (State)        (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	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. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. 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	4/15/2020		M		2087	A	$86.95	2087	D
Common Stock	4/15/2020		S(1)		2087	D	$200.0144 (2)	0	D
Common Stock	4/15/2020		M		1447	A	$133.50	1447	D
Common Stock	4/15/2020		S(1)		1447	D	$200.0008 (3)	0	D

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. 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		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 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
Non-Qualified Stock Option (Right to Buy)	$86.95	4/15/2020		M			2087	3/16/2019 (4)	3/16/2028	Common Stock	2087.0	$86.95	6262	D
Non-Qualified Stock Option (Right to Buy)	$133.5	4/15/2020		M			1447	3/15/2020 (5)	3/15/2029	Common Stock	1447.0	$133.50	5788	D

Explanation of Responses:
(1)	The shares covered by this Form 4 were exercised and sold pursuant to a Rule 10b5-1 Sales Plan dated as of August 7, 2019, which is intended to comply with Rule 10b5-1 promulgated under the Securities Exchange Act of 1934, as amended.
(2)	The price reported in Column 4 represents the weighted average sale price per share. The actual sale prices ranged from a low of $200.00 per share to a high of $200.13 per share. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer, or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.
(3)	The price reported in Column 4 represents the weighted average sale price per share. The actual sale prices ranged from a low of $200.00 per share to a high of $200.01 per share. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer, or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.
(4)	This option was granted on March 16, 2018 and is exercisable as the option vests. The option vests over a five year period, with 20% of the shares subject to the option vesting on each anniversary of the grant date.
(5)	This option was granted on March 15, 2019 and is exercisable as the option vests. The option vests over a five year period, with 20% of the shares subject to the option vesting on each anniversary of the grant date.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Young Micah W C/O MASIMO CORPORATION 52 DISCOVERY IRVINE, CA 92618			EVP & Chief Financial Officer

Signatures
/s/ David J. Van Ramshorst, Attorney-In Fact		4/15/2020
**Signature of Reporting Person		Date