The 9th exemption regulation to the StVO came into force on 15.10.1998 and has been valid indefinitely since 11.11.2010. The previously issued 100 km/h speed limit certificates remain valid. The exemption regulation provides for the possibility of increasing the maximum speed for passenger cars with trailers and for multi-lane motor vehicles with a maximum permissible mass of up to 3.5 t with trailers to 100 km/h on freeways and motorways. The background to this regulation is the technical development of vehicles and combinations in the field of road safety technology. There is no longer a confirmation relating only to a fixed combination of vehicles and trailers. It is now possible to drive at 100 km/h with a trailer that is approved for 100 km/h with different towing vehicles.