Section 39: Use of trade registration mark and number
The Central Motor Vehicles Rules, 1989.State Rules of Bihar · 1988
(1) A trade registration mark and number shall not be used upon more than one vehicle at a time or upon any vehicle other than a vehicle bona fide in the possession of the 65d[ dealer or manufacturer of automobiles or automobile ancillaries or a test agency specified in rules 126.] in the course of his business or on any type of vehicle other than the one for which the trade certificate is issued.
(2) The trade certificate shall be carried on a motor vehicle in a weatherproof circular folder and the trade registration mark shall be exhibited in a conspicuous place in the vehicle.