Clarivate declared a comprehensive crackdown on citation manipulation Clarivate was compelled to remove more than 1,000 researchers from their Highly Cited Researcher list due to evidence of citation gaming. Citation gaming has become increasingly sophisticated, driven by the high incentives associated with achieving the status of a Highly Cited Researcher. A group of researchers expelled from Highly Cited list are members of the Biochar citation ring led by scientists from Korea, Hong Kong, and Germany.