The deal was recorded as Wanxiang officially closed on the purchase of Fisker's assets on Friday and Monday, said Paul Cumberland, Wanxiang America's director of investments.
The Delaware property near Newport was sold for $18 million, the same price Fisker paid for it in 2010, the county reported.
The buyer was WX Delaware Real Estate Holding Co., based in Elgin, Ill., said Antonio Prado, county spokesman.
Prado said the county and state each received $270,000 in real estate transfer taxes.
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That means Fisker's assets are now the property of Wanxiang America Inc., the U.S. arm of China's largest auto parts manufacturer.
The company won an auction for Fisker's assets last month for $149 million in bankruptcy court, beating out another Chinese company, Hybrid Tech Holdings LLC, which had acquired Fisker's federal loan.
But until Monday, the sale was not official, and the value of the Delaware plant had never been broken out.
Gary Wetzel, Wanxiang chief operating officer, also based in Elgin, confirmed the holding company was an affiliate of Wanxiang.
Fisker, the plug-in hybrid auto manufacturer, planned to launch its second-generation line, the Atlantic, from the former General Motors plant, which shut down in 2009. Fisker acquired the plant shortly thereafter, with the help of federal and state incentives.
But a series of problems and miscalculations caused Fisker to file for bankruptcy protection last year.
Wanxiang has pledged to restart the brand and has said it would consider using the Delaware fac! ility for mass production.
Wanxiang recently indicated on its new Fisker Web page, thenewfisker.com, that it was actively deliberating about the future of the plant.
Cumberland said some of the sale closed on Friday, and the real estate sale closed on Monday. The closing came after a federal antitrust review.