Diddy [real name Sean Combs] is being sued by a man who claimed to have been punched in the face by the rapper, reports the BBC.
Court papers alleged Gerard Rechnitzer was "attacked, assaulted and battered" outside a nightclub in Hollywood.
But Mr Combs's lawyer called the suggestion "completely baseless".
It was "just another example of an opportunist seeking to fabricate a lawsuit based on a flat-out lie", Mr Combs did not hit anyone, and Mr Rechnitzer suffered no injuries or damages whatsoever. There is no case. It is that simple."
The papers were filed on Friday at the Los Angeles County Superior Court. They suggested that Mr Rechnitzer, 27, was attacked after he approached Mr Combs at Teddy's, inside the Roosevelt Hotel, on 25 February.
Diddy, 37 was said to have been talking to Mr Rechnitzer's girlfriend. He then allegedly swore before hitting Mr Rechnitzer, causing him to "fly backwards several feet" into a vehicle behind him. A local police spokesman said officers were investigating a complaint by Mr Rechnitzer that he was punched in the face. However, he did not identify the other man who was believed to be involved.