Exhibit 31.3
CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICER
Pursuant to Rule 13a-14(a) adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
I, Catherine Szyman, certify that:
1. | I have reviewed this Amendment No. 1 to the Annual Report on Form 10-K of Masimo Corporation; and |
2. | Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report. |
Dated: May 1, 2026 | /s/ CATHERINE SZYMAN |
| Catherine Szyman |
| Chief Executive Officer |
| (Principal Executive Officer) |