Calumet Specialty Products Partners, L.P.

John (Jack) Boss

Class I director

John (“Jack”) G. Boss has served as a member of the board of directors of Calumet, Inc. since July 2024. He previously served as a member of the board of the General Partner since August 2022. Mr. Boss brings over 40 years of experience to the Board of Calumet. He currently serves on the Board of Directors of Cooper-Standard (NYSE: CPS), Wabash National (NYSE: WNC) and Libbey, Inc. Most recently, he was the President and Chief Executive Officer of Momentive Performance Materials, a specialty chemicals and materials business from 2014 until 2020. Prior to this role, Mr. Boss served in the role of President of Honeywell Safety Products from 2012 to 2014. Mr. Boss held various managerial roles within Honeywell’s Specialty and Chemicals businesses from 2003 through 2014. Prior to Honeywell, Mr. Boss served as Vice President at Great Lakes Chemical Corporation. Mr. Boss holds a B.S. in Mechanical Engineering from West Virginia University and an MBA from Rutgers University.

Mr. Boss brings extensive specialty chemicals and materials knowledge. In addition, he brings to the board of directors of our general partner a broad range of experiences and skills as a result of his service as a director of other public and private companies.