NEW YORK--Two federal judges on Wednesday approved a key settlement between J.P. Morgan Chase & Co. (JPM) and customers of bankrupt MF Global Holdings Ltd. that should free up more than $1 billion for the customers of the defunct brokerage.

U.S. District Judge Victor Marrero and U.S. Bankruptcy Court Judge Martin Glenn both approved the deal, which calls for J.P. Morgan to pay $100 million to reimburse customers and back away from $400 million in claims. Among other things, the deal allows foreign MF Global customers to begin getting more money back from the coffers of James W. Giddens, the trustee unwinding MF Global's brokerage.

"These settlements are effectively the key that unlocks the rest," said Hughes Hubbard & Reed LLP's James B. Kobak Jr., a lawyer for Mr. Giddens. Mr. Kobak referred to a hearing earlier in the case in which MF Global was referred to as a train wreck with pieces all over the track that had to be cleaned up.

"For customers, this settlement gets the rest of the train back on the track," Mr. Kobak said. The settlement, he explained, frees up the payback of money for many of MF Global's U.K. customers. While Judge Glenn approved a settlement for them earlier this year, the J.P. Morgan deal frees up the cash that will actually allow that to be set in motion.

As a result of the settlement, one group of customers that has already received about 89% of its money back is expected to soon be up to 94% and more soon after. Foreign options account holders, who have to this point received less than 20% of their money, will get up to as much as 65% and possibly more after.

"At the start of this case, it certainly seemed doubtful that customers would recover what they already have and should recover in the future," Judge Glenn said in approving the settlement. Mr. Giddens expects to officially request the allocation of money to customer funds by September.

Last month, Mr. Giddens said commodities customers who dealt on U.S. exchanges, with claims of some $5.4 billion, are expected to recover 96 cents on the dollar, seven cents more than his previous estimate.

Recoveries for U.S. futures and commodities customers with accounts overseas, with claims totaling $878 million, will range from 84 cents to 91 cents on the dollar, he said.

The unusual hearing at the Daniel Patrick Moynihan U.S. Courthouse in lower Manhattan encompassed both the MF Global bankruptcy case and a U.S. District Court proceeding before Judge Marrero, in which former MF Global customers are suing ex-Chief Executive Jon S. Corzine, other top executives, and accounting firm PricewaterhouseCoopers LLP over missing funds. J.P. Morgan, a trustee and custodian for MF Global's brokerage unit, was also a defendant in that suit. The class-action suits against Mr. Corzine and the others will continue, a lawyer for the customers said.

While the proceedings have occurred concurrently, this particular settlement was ordered to be held as one hearing because of how it crossed over into both matters. Only a separate group of customers suing Mr. Corzine and the executives objected to the settlement at the Wednesday hearing, but slight wording changes assuring them that they'd be able to sue later appeared to alleviate their concerns.

Mr. Giddens is winding down MF Global's broker-dealer business for the benefit of customers under the authority of the Securities Investor Protection Act, which governs the liquidation of failed brokerage firms.

"I am extremely pleased with the approval of this settlement and am grateful for the coordination of the courts and the cooperation of all the parties in this matter," said Mr. Giddens.

The liquidation is separate from MF Global Holdings Ltd.'s Chapter 11 proceeding. Louis Freeh, a former director of the Federal Bureau of Investigation who has since stepped down as trustee of the holding company, also sued Mr. Corzine and other executives for their role in the collapse.

Led by Mr. Corzine, a former New Jersey governor and Goldman Sachs Group Inc. (GS) chairman, MF Global went down in October 2011 when customers panicked over the New York firm's large bets on European debt. The firm's failure exposed what appeared to be a $1.6 billion shortfall in U.S. customer accounts.

The former executives, including Mr. Corzine, have denied any wrongdoing in connection with that shortfall. While investors have filed a number of civil suits against the firm's top brass, no one has been charged with criminal wrongdoing.

(Dow Jones Daily Bankruptcy Review covers news about distressed companies and those under bankruptcy protection. Go to http://dbr.dowjones.com)

-Patrick Fitzgerald in Washington contributed to this article.

Write to Joseph Checkler at joseph.checkler@dowjones.com. Follow him on Twitter at @JoeCheckler

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