Veh. Code, § 27900

(a) A motor vehicle or combination of vehicles used to carry the property of others for hire or used to carry passengers for hire, a truck or truck tractor with three or more axles or a truck tractor with a semitrailer, and all commercial motor vehicles, as defined in subdivision (c) of Section 34601, shall have displayed on both sides of each vehicle or on both sides of one of the vehicles in each combination of vehicles the name or trademark of the person under whose authority the vehicle or combination of vehicles is being operated.

(b) The name or trademark of the motor carrier operating a vehicle or combination of vehicles listed in subdivision (a) under a rental agreement with a term of not more than 30 calendar days is not required to be displayed if all of the following requirements are met:

(1) The name or trademark of the lessor is displayed on both sides of each vehicle or on both sides of one of the vehicles in each combination of vehicles.

(2) Any of the following numbers issued to the lessor are displayed on both sides of each vehicle or on both sides of one of the vehicles in each combination of vehicles:

(A) The carrier identification number issued by the United States Department of Transportation.

(B) A valid operating authority number.

(C) A valid motor carrier of property number.

(3) (A) A copy of the rental agreement entered into by the lessor and the vehicle operator is in the vehicle or combination of vehicles.

(B) The rental agreement shall be available for inspection immediately upon the request of an authorized employee of the department, any regularly employed and salaried police officer or deputy sheriff, or any reserve police officer or reserve deputy sheriff listed in Section 830.6 of the Penal Code.

(C) If the rented vehicle or combination of vehicles is operated in conjunction with a commercial enterprise, the rental agreement shall include the operator’s carrier identification number or motor carrier of property permit number.

(c) A vehicle or combination of vehicles that is in compliance with Section 390.21 of Title 49 of the Code of Federal Regulations shall be deemed to be in compliance with subdivision (b).

(d) All names, trademarks, and other identifiers for companies no longer in business, no longer operating with the same name, or no longer operating under the same operating authority, shall be removed from or covered over on every motor vehicle or combination of vehicles listed in subdivision (a), within 60 days from the change of company ownership or operation. Those vehicles or combinations of vehicles shall be remarked pursuant to subdivision (a) before they may be operated on the highways.