On August 11, 2023, the board of directors of iRhythm Technologies, Inc. appointed Marc Rosenbaum, the Company?s Senior Vice President, Finance, to serve as the Company?s Chief Accounting Officer and designated Mr. Rosenbaum as the Company?s principal accounting officer for purposes of the rules and regulations of the Securities and Exchange Commission, effective immediately. Mr. Rosenbaum, age 51, has served as the Company?s Senior Vice President, Finance since May 2023. Prior to joining the Company, between May 2014 and May 2023, Mr. Rosenbaum served in various roles at NuVasive, Inc., including as Vice President, Corporate Controller and Chief Accounting Officer from May 2022 to May 2023, as Vice President and Corporate Controller from April 2018 to May 2022, and as Senior Director and Assistant Corporate Controller from May 2014 to March 2018.

Between 2010 and May 2014, Mr. Rosenbaum held roles of increasing responsibility in the finance department of Gen-Probe, Inc. and Hologic, Inc. (which acquired Gen-Probe in August 2012), most recently serving as Hologic?s Senior Director and Controller for the diagnostics division. Prior to joining Gen-Probe, Mr. Rosenbaum served as Senior Director, Finance and Accounting, at Elan Pharmaceuticals, Inc. (formerly Dura Pharmaceuticals, Inc.) from 1997 to 2010. Mr. Rosenbaum holds a bachelor?s degree in Business Economics from the University of California at Santa Barbara and is a Certified Public Accountant (inactive).