Hagens Berman accused Ford Motor Co of rigging its F-250 and F-350 Super Duty trucks with emissions-cheating devices to ensure they passed tests, in the lawsuit filed on Wednesday. The lawsuit also names Bosch as a defendant.

"Bosch takes the allegations of manipulation of the diesel software very seriously. It is a well-known fact that these allegations remain the subject of investigations and civil litigation involving Bosch," the company said in a statement.

"Bosch is cooperating with the continuing investigations in various jurisdictions, and is defending its interests in the litigation," it added, declining to comment further.

(Reporting by Ilona Wissenbach and Christoph Steitz. Editing by Jane Merriman)