Can a car dealership sell a unregistered car?

I don't know about car dealerships in particular, and this answer may vary by state, but I've bought and sold a lot of cars so hopefully this will offer a bit of help.

You can own a car that's unregistered (or even untitled) but you can't drive it or park it on the road. Many project cars are sold in an non-running state and there's no reason to register a non-running car. However, when the state transfers the title, they will probably charge the new owner the fee for the registration at that point (because they can).

If the car is moving from one state to another, then the new owner simply takes it in to register in his/her state -- the previous registration (or lack there of) holds no bearing. They only care about the Title (and maybe an inspection -- depends on the state).

The Title is the key to car sales -- the registration is basically a fee to the state for use of the roads, it isn't part of the car's oownership at all. Most car dealerships have all of their cars covered under special "dealer plates" that negate the per-car registration system that the rest of us use... so they're under a different set of rules there.

So as far as I know the registration is moot for dealerships... they care about the title. The title is the actual ownership papers. When you buy a car with a car loan (ie 'under lien'), the car actually belongs to the bank, not you; they hold the title -- you get a special piece of paperwork that looks fancy with lots of writing and gives you the right to register it, but you do NOT hold the title...they'll mail it to you after you complete all your payments. So...anyhoo, if a car has been repossessed then the owner (the bank) can give anyone else the right to register it for them as they please, wherever they please, the registration holds no bearing on the ownership or sale of the vehicle.

If you are buying a car from a dealership, I believe that they usually include the first registration in the closing costs of the deal -- otherwise is isn't legal to drive the car home! It would be something to ask the dealer if you are buying a used car that has plates already, just to be sure.