People stand next to windows above an exterior sign at the Lehman Brothers headquarters in New York in this September 16, 2008 file photo. REUTERS/Chip East/Files

(Reuters) - Lehman Brothers Holdings Inc has filed a lawsuit against Barclays Capital Inc alleging the British bank took control of excess assets in collusion with Lehman executives when it bought its U.S. brokerage business a year ago, court documents show.

Lehman filed for bankruptcy on September 15, 2008, in the largest U.S. bankruptcy in history. Its flagship U.S. brokerage business was sold to Barclays less than a week later in a hurriedly assembled deal.

Lehman said in September this year that Barclays Capital got an $8.2 billion “windfall profit” due to the fire sale of its business for an undisclosed $5 billion discount off the book value of securities transferred to Barclays.

“The windfall to Barclays was not disclosed to the Court, the Lehman Boards or Lehman’s lawyers so as to allow the transfer to Barclays of billions of dollars in excess assets, without consideration, in a manner designed to avoid judicial, corporate and creditor oversight,” Lehman said in a Monday court filing.

The charges come after Lehman received approval in June to probe whether Barclays got “too good of a deal” when it bought Lehman’s brokerage business, as the British bank was able to quickly book a $4.2 billion gain on its $1.75 billion purchase.

Barclays said at the time that it did not expect the probe to result in any additional claims.

In the lawsuit, Lehman requested the court to order Barclays to “disgorge to Lehman any ill-gotten gains it obtained” and pay punitive damages.

A Barclays Asia spokesman said in an email that all queries on the lawsuit should be directed to its New York office. Barclays’ New York officials were not immediately available for comment, outside of normal U.S. hours.

The case is In re: Lehman Brothers Holdings Inc, U.S. Bankruptcy Court, Southern District of New York, No. 08-13555. (Reporting by Supantha Mukherjee and Ajay Kamalakaran in Bangalore; Editing by Muralikumar Anantharaman)