X0303 5 2011-01-01 0 0 0 0000937556 MASIMO CORP MASI 0001228621 KIANI JOE E C/O MASIMO CORPORATION, 40 PARKER IRVINE CA 92618 1 1 0 0 CEO and Chairman of the Board Common Stock 2010-12-31 5 M 0 2152 A 9914 I See Footnote Between March 31, 2010 and December 31, 2011, Mr. Kiani acquired 2,152 shares of Masimo Corporation common stock at various prices under the Masimo Retirement Savings Plan. The information in this report is based on a plan statement dated December 31, 2010. /s/ Mark de Raad, Attorney-In-Fact 2011-02-14