BMW has confirmed its head office was searched this week by European Union officials investigating an alleged cartel among five German carmakers.
EU investigators are looking into allegations that BMW, Daimler, VW, Audi and Porsche colluded to limit their spending on emissions technology.
BMW said EU staff had inspected its Munich offices, adding that it was assisting the regulators in their work.
Also on Friday, Daimler said it had filed an application for leniency.
The firm, which owns Mercedes-Benz, also has no current plans to set aside funds for possible fines, according to chief financial officer Bodo Uebber.