The organization in charge of Berlin's commuter rail service is suing Bombardier Transport (TSE: BBD) for $460 million over allegedly defective trains.
Deutsche Bahn is suing the German-based Bombardier subsidiary in regional court because of what it describes as serious errors.
The rail operator says the wheels and axle-shafts on trains have had to be redesigned and replaced at great financial expense.
Braking systems and traction motors have also been adapted and, in some cases, replaced.
It says the lawsuit comes after a failure to reach an out-of-court settlement with Bombardier. There are separate suits pending against Bombardier in Munich and Berlin regional courts, related to other trains, with Deutsche Bahn seeking another $214 million in compensation.
In response, Bombardier has issued a news release disputing the allegation and calling it defamatory.