Registration in dns-hosting of an already existing domain there

Question

Domain Name System

There is a domain that is serviced in some dns-hoster (dyndns, ypdns, etc.), the nserver-record points to the hosting server. Some malefactor registers the same domain in the same hosting. What ip-addresses will the hosting server give: the information of the old client, the information of the new client, or will they not let you register a domain at all?

Answer 1

Of course they won't.