The liquidator for Bernard Madoff’s business, who sued longtime investor Jeffry Picower to recover $6.7 billion for victims, said he now seeks $500 million more after finding additional evidence of excess withdrawals.

Picower withdrew $7.2 billion from Madoff’s firm, making the Florida philanthropist the biggest beneficiary of Madoff’s $65 billion Ponzi scheme, trustee Irving Picard said in papers filed in US Bankruptcy Court in New York.