Towing Issues: requirements to release a ppi in calif, unlicensed vehicle, current registrations

Question
may a tow company in calif, require for a vehicle to be have current registration in order to be released when it is a private property impound, with no police release needed?  ty.   (i did check the dmv site,  still need specific answer i did not find there, ty)

Answer
Well it goes back to liability issues...

An unlicensed vehicle is illegal to operate on the roadways, and if something happened a lawyer would try to get the tow company to be part of the issue since they let it go...

And as to specific answers, I really can not say what a company policy would be, but I know where I work we require that they have valid and current registrations.