Fisker Automotive Holdings Inc filed for bankruptcy protection in 2013. Above a Fisker Karma. [Provided to China Daily]

Two Chinese-backed companies are locked in a bidding war, culminating next week, to take over bankrupt United States carmaker Fisker Automotive Holdings Inc.

The prize is 12-and-a-half patents and a possible toehold in both the US and Chinese markets. The rest is a harder sell.

Fisker hasn't made a vehicle since 2012. Its $103,000 plug-in hybrid sports sedan, the Karma, was called a "basket case" by Consumer Reports.

The company, which lost $139 million in US taxpayer money, was labeled a "loser" by Republican Mitt Romney during 2012 US presidential debates. Its most visible asset is a derelict former General Motors factory that Fisker never used.

China's Wanxiang Group emerged in December as a suitor for Fisker, challenging Hybrid Tech Holdings LLC, a Chinese-backed firm that had been jockeying to take over the bankrupt automaker. The rivals' interest prompted a bankruptcy judge to set a Feb 12 auction for Fisker's assets.

"It's not about the manufacturing," said Steven Szakaly, the National Automobile Dealers Association's chief economist. "It's about the intellectual property."

Fisker's 18 patents cover grille designs, a fender vent and electric-vehicle drivetrain technology, according to the database of the US Patent and Trademark Office. It also has at least 18 more patent applications pending, including in aluminum subframing and solar-car technologies, said Charles Shifley, a patent attorney at Banner & Witcoff Ltd in Chicago.

The patents have many potential applications for buyers eager to break into the growing alternative-fuels market, said Blair Jacobs, a patent lawyer with McDermott Will & Emery in Washington.

"To have a jump start with a portfolio that took three to five years to develop is really substantial," said Jacobs, who has represented automakers in past disputes.

For a Chinese suitor, the Fisker package holds particular promise. The assets would let the buyer revive the Fisker brand in the world's biggest auto market, which is struggling to reduce some of the globe's worst air pollution. It would also provide an entry point to selling cars in the US.