California Code, Vehicle Code - VEH § 8054

(a) Upon the application for transfer of ownership of a fleet of vehicles apportionately registered pursuant to this article, the department shall permit registration in the new owners name without reassessing the registration and vehicle license fees, if the application of the new ownership is for the same fleet interstate operation as the previous owner.

(b) The new owner, lessee, or their designee, shall certify the declared gross vehicle weight of the vehicle or vehicles on a single form for all commercial motor vehicles registered in the fleet owner's or lessee's name. The department shall reassess the weight fees if the declared gross vehicle weight is increased. The weight fees will be assessed at a prorated rate.