(Adds details of Sears' restructuring plan, criticism of Lands' End transaction)
By Jonathan Stempel and Jessica DiNapoli
NEW YORK, April 18 (Reuters) - Sears Holdings Corp sued longtime former Chairman Eddie Lampert, his hedge fund ESL Investments and others like Treasury Secretary Steven Mnuchin, claiming they illegally siphoned billions of dollars of assets from the retailer before it went bankrupt.
The lawsuit, made public on Thursday, was filed by the restructuring team winding down Sears' bankruptcy estate and suing on behalf of creditors, many of whom blame Lampert for the retailer's downfall.
It followed the billionaire's $5.2 billion purchase in February of most Sears assets, including the DieHard and Kenmore brands, after a bankruptcy auction.
The complaint seeks the repayment of "billions of dollars of value looted from Sears," including while it was in what Lampert would later call a "death spiral" where it sold core assets to meet daily expenses with no real plan for becoming profitable.
"Had defendants not taken these improper and illegal actions, Sears would have had billions of dollars more to pay its third-party creditors today and would not have endured the amount of disruption, expense, and job losses resulting from its recent bankruptcy filing," the complaint said.
Sears filed for Chapter 11 protection in October after a prolonged decline under Lampert marked by large losses, scant investment and lost market share to retailers such as Walmart Inc, Home Depot Inc and Amazon.com Inc.
Others sued include ESL President Kunal Kamlani; Bruce Berkowitz and his Fairholme Capital Management, which was a large Sears shareholder; and Seritage Growth Properties, which took over 266 of Sears' best stores in a 2015 spinoff.
Mnuchin, a college roommate of Lampert's at Yale University, had been a director at Sears and ESL, and previously worked with Lampert at Goldman Sachs.
In a statement on behalf of ESL, Lampert and Kalmani, ESL said it vigorously disputed the lawsuit, calling the allegations "misleading or just flat wrong," and saying all transactions were done in good faith and for shareholders' benefit.
Fairholme said it was reviewing the complaint. Seritage and the Treasury Department did not immediately respond to requests for comment.
Lampert created Sears Holdings through the 2005 merger of Sears, Roebuck & Co and Kmart Holdings Corp.
According to the complaint, Lampert and other insiders had by 2011 begun hatching a plan to "strip" Sears of assets, as the Hoffman Estates, Illinois-based retailer's performance fell short and more ESL investors were demanding their money back.
The complaint said Lampert ordered the creation of bogus financial plans projecting a Sears turnaround, and used them to help transfer five major assets worth more than $2 billion, including Land's End and Sears Hometown Outlet.
Sears' estate criticized Lampert for rejecting as a "non-starter" a potential offer from Tommy Hilfiger and Leonard Green & Partners for Lands' End, which they valued at $1.6 billion including net debt, and instead spinning it off to himself, ESL and others, with Sears getting just a $500 million dividend.
It also said the $2.58 billion Seritage spinoff undervalued the real estate by at least $649 million, stuck Sears with hundreds of millions of dollars of rent and fees from leasing most of the 266 stores back, and was structured to benefit shareholders like Lampert, in part through Seritage's payment of dividends.
Seritage won a vote of confidence last July by obtaining a $2 billion loan package from Warren Buffett's Berkshire Hathaway Inc. Berkshire is not a defendant.
Thursday's lawsuit seeks a declaration that the alleged looting constituted "fraudulent transfers" that should be undone or, more likely, justified damages.
It was filed with the U.S. bankruptcy court in White Plains, New York less than an hour after Sears filed a proposal to create a liquidating trust that could pursue lawsuits over the Land's End and Seritage transactions.
The reorganized Sears was expected to have about 425 Sears and Kmart stores, down from roughly 3,500 at the time of the 2005 merger.
The case is Sears Holdings Corp et al v Lampert et al, U.S. Bankruptcy Court, Southern District of New York, No. 19-ap-08250. The main bankruptcy case is In re Sears Holdings Corp in the same court, No. 18-bk-23538. (Reporting by Jonathan Stempel in New York; editing by Steve Orlofsky, Marguerita Choy and Lisa Shumaker)