MASI Masimo Corporation

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                                                                                   
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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 * Lee Yongsam	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, CIO
(Last)          (First)          (Middle) C/O MASIMO CORPORATION, 52 DISCOVERY	3. Date of Earliest Transaction (MM/DD/YYYY) 4/13/2020
(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	4/13/2020		M		10000	A	$28.03	85000	D
Common Stock	4/13/2020		S(1)		10000	D	$180	75000	D
Common Stock	4/14/2020		M		6000	A	$31.01	81000	D
Common Stock	4/14/2020		S(1)		6000	D	$185.0192 (2)	75000	D
Common Stock	4/14/2020		M		4000	A	$37.84	79000	D
Common Stock	4/14/2020		S(1)		4000	D	$185.0024 (3)	75000	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)	$28.03	4/13/2020		M			10000	2/18/2015 (4)	2/18/2024	Common Stock	10000.0	$28.03	0	D
Non-Qualified Stock Option (Right to Buy)	$31.01	4/14/2020		M			6000	3/20/2016 (5)	3/20/2025	Common Stock	6000.0	$31.01	0	D
Non-Qualified Stock Option (Right to Buy)	$37.84	4/14/2020		M			4000	3/1/2017 (6)	3/1/2026	Common Stock	4000.0	$37.84	26000	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 March 10, 2020, 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 $185.00 per share to a high of $185.27 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 $185.00 per share to a high of $185.06 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 February 18, 2014 and is exercisable as the option vests. This option vested 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 20, 2015 and is exercisable as the option vests. This option vested over a five year period, with 20% of the shares subject to the option vesting on each anniversary of the grant date.
(6)	This option was granted on February 29, 2016 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
Lee Yongsam C/O MASIMO CORPORATION 52 DISCOVERY IRVINE, CA 92618			EVP, CIO

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