The owner of Saab, which is bankrupt, has sued General Motors for $US3 billion.
Spyker Cars accuses GM of forcing the Swedish car firm out of business by interfering with a potential sale.
Saab had been in takeover talks with a Chinese company and filed for bankruptcy in December when those talks failed.
GM, which owned part of Saab, did not want Chinese carmakers accessing Saab's technology licences.
GM says the accusations are baseless.