Dr. Stein has served as an independent director at Axalta since September 2023. Dr. Stein served as President and CEO of TransDigm Group Incorporated from April 2018 until his retirement in September 2025. Dr. Stein is a member of the Board of Directors of TransDigm and has been since April 2018. Dr. Stein joined TransDigm in 2014 as Chief Operating Officer of the Power and Controls Segment. He then became the company's Chief Operating Officer and President in January of 2017, before being promoted to CEO in April of 2018. TransDigm is a leading global designer, producer and supplier of highly engineered aircraft components for use on nearly all commercial and military aircraft in service today. Prior to joining TransDigm, Dr. Stein worked for Precision Castparts Corporation, now a division of Berkshire Hathaway, in a variety of senior leadership roles. Previously, Dr. Stein served as a division president for Cooper Industries and Tyco Electronics/Raychem Corporation. Among other philanthropic endeavors, he serves as a Trustee for the Cleveland Institute of Music, an independent conservatory of Music in Cleveland, Ohio, and as a Trustee for Gilmour Academy, an independent, co-educational school in the Cleveland suburb of Gates Mills, Ohio. Dr. Stein earned his bachelor’s degree in Chemistry from Hobart College and his master’s and Ph.D. in Inorganic Chemistry from Stanford University.