Irving Picard, the lawyer trying to recover money for defrauded investors of convicted swindler Bernard Madoff, is seeking another $555 million from UBS.
Picard had already sued the Swiss bank last month for more than $2 billion, accusing it of collaborating in Madoff's massive Ponzi scheme.
Now Picard has come back for more.
The second filing against UBS would bring the total recoveries claimed from UBS to around $2.5 billion.
The lawyer has also begun a legal action against multi-billion dollar U.S. money manger Tremont Group Holdings.
Picard's latest action against UBS, filed with a U.S. court, seeks to recover the extra cash for distribution to defrauded Madoff customers with valid claims. The exact amount will be determined at trial.
UBS rejected the fresh claims.
"The US trustee's allegations are completely unfounded and without merit," UBS spokeswoman Tatiana Togni said.
"UBS was not aware of any wrongdoing by Madoff. We will take all appropriate steps to demonstrate that the allegations are false and unfounded," she said.
In Picard's initial claim, UBS was accused of sponsoring foreign feeder funds that sent client money to the once-respected money manager, lending them "an aura of legitimacy" while shielding itself from liability through secret side agreements.
Picard has also taken action against JPMorgan Chase & Co to recover $6.4 billion and HSBC for $9 billion
Madoff is serving a 150-year prison sentence after pleading guilty in March 2009 to running a decades-long investment fraud of up to $65 billion.
The latest case against UBS is Picard v. UBS AG et al, U.S. Bankruptcy Court, Southern District of New York, No. 10-05311.
Picard's action against Tremont accuses the firm of being the second-largest feeder-fund network in the Madoff Ponzi scheme, according to a statement from the lawyer.
Tremont was not immediately available for comment.
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