MASIMO CORP — Director's Dealing 2017

May 1, 2017

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MASIMO CORP (MASI)
CIK: 0000937556
Period of Report: 2017-04-27

Reporting Person: KIANI JOE E (Director, CEO and Chairman of the Board)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2017-04-27	Common Stock	M	45841	$30.79	Acquired	165082	Direct
2017-04-27	Common Stock	S	45841	$101	Disposed	119241	Direct
2017-05-01	Common Stock	M	100000	$30.79	Acquired	219241	Direct
2017-05-01	Common Stock	S	100000	$103	Disposed	119241	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2017-04-27	Non-Qualified Stock Option (Right to Buy)	$30.79	M	45841	Disposed	2018-02-07	Common Stock (45841.0)	Direct
2017-05-01	Non-Qualified Stock Option (Right to Buy)	$30.79	M	100000	Disposed	2018-02-07	Common Stock (100000.0)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	779290	Indirect
Common Stock	352919	Indirect
Common Stock	359000	Indirect
Common Stock	2250291	Indirect
Common Stock	10373	Indirect
Common Stock	9000	Indirect

Footnotes

F1: The shares covered by this Form 4 were sold pursuant to a Rule 10b5-1 Sales Plan dated as of March 8, 2017 which is intended to comply with Rule 10b5-1 promulgated under the Securities Exchange Act of 1934, as amended.

F2: Shares held in three trusts for which Mr. Kiani is not the sole trustee.

F3: Shares held in one trust for which Mr. Kiani is the sole trustee.

F4: Shares held in Masimo Retirement Savings Plan.

F5: Shares held by an immediate family member for which Mr. Kiani exercises voting and investment control.

F6: This option was granted on February 7, 2008 and is exercisable as the option vests. This option vests over a five-year period, with 20% of the shares subject to the option vesting on each anniversary of the grant date.