Tian Tian joined the Patent Office of the China National Intellectual Property Administration (CNIPA) in 2007, working in the Medical and Biological Invention Examination Department. In 2014, she was transferred to the former Patent Reexamination Board. She currently serves as Deputy Division Director (Level-2 Researcher) and Level-2 Patent Examiner in the First Medical and Biological Appeals Division of the Reexam ination and Invalidation Department of the Patent Office, CNIPA. She is recognized as a high-level expert at the CNIPA.