The exiled businessman, who last year lost a multibillion-pound High Court fight with Chelsea Football Club owner Roman Abramovich, was found dead at his home in Berkshire.
A spokesman for his company, Bell Pottinger, said Berezovsky was found at his home in Ascot, Berkshire.
"His body was found by his bodyguard," he said.
It was widely reported the former mathematics professor had taken his own life, but that was not officially confirmed.
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