Saab, the Swedish maker of road-hugging sports cars and sedans, filed for bankruptcy on Friday as part of sweeping restructuring plan by its parent, the General Motors Corporation.

Saab, which G.M. said would become an independent business by 2010, went to a Swedish court for protection from its creditors, and said the company would — with assistance from the Swedish government — reorganize to pave the way for private investors to buy all or part of it.