John Duffey is the chief financial officer of Six Flags Entertainment Corporation, responsible for the finance and information technology functions of the company, which is the largest regional theme park operator in the world.

Prior to joining Six Flags, John served as executive vice president and chief integration officer of Siemens Healthcare Diagnostics, and was responsible for leading the integration of Siemens Medical Solutions Diagnostics and Dade Behring. Prior to Dade Behring’s acquisition by Siemens AG, John served as the EVP and CFO of Dade Behring.

John holds a BA in accounting from Michigan State University. A father of three, he said of his third-generation Derry and Donegal roots, “The Irish have tremendous pride which is passed down from generation to generation, regardless of where they live. Family is extremely important and growing up in an Irish Catholic family with five siblings and 31 cousins taught me values I will use and cherish throughout my life. I am proud of my Irish heritage and when my children are asked of their nationality, they always have the same answer, ‘Irish.’”