NEW YORK (Reuters) – The judge overseeing the fallout from the Madoff debacle agreed on Tuesday to hear about 2,000 claims by people whose money was invested with the imprisoned swindler via so-called feeder funds, in many cases without their knowledge.

A lawyer for the court-appointed trustee overseeing the disbursement of monies said he would provide the judge with a list of the "feeder funds" — funds that invested their client's money with Bernard Madoff on the advice of Madoff or his intermediaries — within two weeks.

"This is the first step in dealing with this type of issue. Does the customer actually have an account?" David Sheehan, a lawyer for the trustee, New York attorney Irving Picard, told Judge Burton Lifland at a hearing in US Bankruptcy Court.

As part of the recovery of money for thousands of customers of Bernard L. Madoff Investment and Securities LLC (BLMIS), the trustee said in court papers that "approximately 2,000" objections have been filed to his determination of claims of claimants without an account and what constitutes the term "customer."

In a global search for money as of March 31, Picard and his investigators say they have recovered $1.5 billion from the investment fraud orchestrated by Madoff, 71, who is serving a 150-year prison sentence after pleading guilty in March 2009.

His Ponzi scheme, one in which early investors are paid with the money of new clients, drew in as much as $65 billion, according to US prosecutors.

Madoff made few actual trades in securities, according to records cited by investigators.

Sheehan told Judge Lifland that some investors dealt with a feeder fund and not with Madoff or the firm.

"In many cases, they did not even know the feeder fund was invested in Madoff," Sheehan said.

Lifland said he had "no problem with isolating the group" of investors over their claims but he asked the trustee to make it clear how "feeder fund" would be defined since claimants may have directly or indirectly invested with the Madoff firm.

Any hearing on these claims would be October 19 at the earliest, according to the trustee's proposed schedule.

In court on Tuesday, Sheehan said the list of funds included three hedge funds known as Ascot, Gabriel and Ariel run by Ezra Merkin, a New York money manager and former chairman of the GMAC LLC finance company. He also cited funds in the Connecticut-based Fairfield Greenwich Group, co-founded by money manager Walter Noel.

Sheehan told the judge that the list of "feeder funds" would not include banks or pension funds.

The judge on Tuesday also approved a revised agreement for the takeover of the trading platform of the Madoff firm.

The trading unit was sold at auction a year ago to Boston financial company Castor Pollux Securities LLC for up to $25.5 million, a fraction of its previous $1 billion worth.

Picard said in a report to the court last week that his team of lawyers was still investigating and seeking to recover assets in a dozen places around the world, including Britain, Gibraltar, Bermuda, the British Virgin Islands, the Cayman Islands, the Bahamas, Ireland, France, Luxembourg, Switzerland, Canada, Austria and Spain.

"The trustee's international investigations have to date revealed a complex web of tangled investment structures that fed money into the Ponzi scheme, involving several billion dollars and myriad actors," the report said.