NEW YORK (

TheStreet

) -- One year to the day that

Lehman Brothers

filed for bankruptcy it has accused

Barclays

(BCS) - Get Report

of getting a windfall profit of $8.2 billion more than it should have received when it bought excess assets of the failed investment bank a year ago.

Lehman filed for bankruptcy on Sept. 15, 2008. Its U.S. brokerage business was sold to Barclays less than a week after the filing.

Lehman, in a court filing Tuesday in federal bankruptcy court in Manhattan, wants Barclays to be forced to give back some of the money it took as part of the deal, including $5 billion it said was given as extra collateral. Lehman said the extra value wasn't disclosed to the court.

"Certain Lehman executives agreed to give Barclays an undisclosed $5 billion discount off the book value of securities transferred to Barclays, and later agreed to give billions more in so-called 'additional value' that Barclays demanded, but the court never approved," Lehman said in the court filing, according to a report from

Reuters

.

A Barclays spokesman said Lehman is making "an opportunistic claim."

"Now that the economy has begun to stabilize the Lehman Estate is trying to re-trade the deal on the basis of a meritless argument," Michael O'Looney said in an emailed statement.

Lehman is asking the court to amend the deal and a hearing is scheduled for Oct. 15,

Reuters

reports.

-- Reported by Joseph Woelfel in New York

.

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