OK - Here it is straight from our local PD. (the copied the page from the book for me:
5.40CMR 2.22 ($35 fine)
The owner of every truck used to transport goods, wares or merchandise for hire shall have the owner's name marked on the truck, to be plainly visible from each side or from the front and rear of the vehicle. Moreover, motor trucks operated under a lease of more than 30 days shall display either the name of the owner and/or the lessee. For the purpose of this regulation, a motor truck is; "any motor vehicle specially designed or equiped to transport personal property over the ways of the commonwealth and which has a maximum load carrying capacity of over 2000 pounds, and which in not a provate passenger vehicle.