NEW YORK — The victims of Bernard Madoff's massive swindle are only owed the money they invested with his firm and not the $64.8 billion reflected on fictitious statements, a Manhattan bankruptcy judge ruled Monday.

The written decision issued yesterday by U.S. Bankruptcy Court Judge Burton Lifland rejected the victims' arguments that they had legitimate claims based on "securities positions" listed in final Nov. 30, 2008, statements. It upheld a "net equity" formula being used by a trustee overseeing the liquidation and distribution of Madoff's assets.

The ruling determines how much money, if any, victims may get from the industry-financed Securities Investor Protection Corp., which must repay as much as $500,000 for each qualifying claim.

Thousands of customers objected to trustee Irving Picard's methodology, arguing he wrongfully set claims based on their cash deposits minus withdrawals instead of using the amounts on Madoff's final account statements. Lifland sided with Picard.

"Upon a thorough and comprehensive analysis of the plain meaning and legislative history of the statute, controlling Second Circuit precedent, and considerations of equity and practicality, the Court endorses the trustee's net investment method," Lifland said in the 53-page ruling.

Picard, hired by SIPC to repay victims of the $65 billion fraud, has said that using account statements to set claims would let the con man decide who gets what, and include profit from trades that didn't really happen.

Brian J. Neville, a New York-based lawyer representing about 100 victims who lost a total of nearly $110 million in the fraud, said he plans to appeal to the 2nd Circuit Court of Appeals in Manhattan.

"Our firm and our clients are upset," Neville said by phone. "We respectfully disagree with the judge, but as he noted during the oral arguments, this is a case that the 2nd Circuit will ultimately rule on."

Picard has determined about 12,000 claims and approved about 1,900 of them, for a total SIPC commitment of more than $649 million, according to Lifland's ruling.

Customer claims in the case determine what share victims receive from lawsuits filed by Picard against Madoff's biggest investors and beneficiaries, including hedge funds and the con man's wife, Ruth. About a dozen such cases seek the return of about $15 billion in allegedly fake profit.

Under Picard's calculation, some victims may end up owing money if they took out more than they put in. In January, the family of deceased New York real estate magnate Norman F. Levy agreed to pay Picard $220 million for victims to settle claims the family withdrew more than it deposited with Madoff.

Victims wanted their final account statements from Madoff's firm to determine the size of their claims. They argued SIPC was required to base claims based on customers' legitimate expectations. Lifland disagreed, saying the account statements were "entirely fictitious."

"The only verifiable amounts that are manifest from the books and records are the cash deposits and withdrawals," Lifland said. Customers' legitimate expectations aren't relevant if they apply to "absurd results," he said.