President and CEO, MKS Inc. Age: 63 Director since: 2020 Other Current Public Company Directorships: Cognex Corporation Background Dr. Lee has served in progressive leadership roles since joining MKS in 2007, culminating in his appointment as our President and Chief Executive Officer in 2020. He previously served as our President from 2019 to 2020; our President and Chief Operating Officer from 2018 to 2019; our Senior Vice President and Chief Operating Officer from 2016 to 2018; our Senior Vice President of Business Units from 2014 to 2016; our Senior Vice President, Controls, HPS (our integrated process solutions business) and Pressure, Flow, Measurement and Control (PFMC) from 2012 to 2013; our Senior Vice President, Controls and PFMC from 2011 to 2012, and our Group Vice President, Controls and Information Technology products from 2007 to 2011. Prior to MKS, Dr. Lee served in leadership roles at Applied Materials, a global leader providing processing equipment to the semiconductor and display markets, from 2002 to 2007, including Managing Director of Factory Technology and Projects within the Solar Business Group and General Manager of the Cleans Product Group and the Maydan Technology Center. Prior to Applied Materials, Dr. Lee served as Research Director of the Silicon Fabrication Research Department at Lucent Technologies, Inc., a voice, data, and video communications provider, from 1997 to 2002 and as a Member of the Technical Staff in the Plasma Processing Research Group within Bell Labs from 1991 to 1997. In addition to the other current public company directorship listed above, he has served as Co-Chair of the Mass Opportunity Alliance since 2024 and a member of the Executive Committee of the Board of Directors of the Massachusetts High Technology Council (MHTC) since 2021. He previously served as Chair of MHTC from 2023 to 2025 and as Vice Chair of MHTC from 2021 to 2023. Dr. Lee holds a B.S. from Princeton University and both an M.S.CEP and a Ph.D. from the Massachusetts Institute of Technology, all in Chemical Engineering. Key Qualifications as Determined by our Board of Directors Deep understanding of our extensive and complex product portfolio, driven by strong technical education and background Unique leadership perspective from progressive leadership roles at MKS and Applied Materials, one of our largest customers Direct knowledge of and experience in engineering, operations, mergers and acquisitions, and business development