Domain Transfer Locks
Some domain names, such a .com, will have a lock associated with it. This lock was another obstacle designed to ensure that .com domains couldn’t be easily moved away or edited without prior consent. You can see the status of a domain name in the whois. Look out for:
Status: clientTransferProhibited, clientUpdateProhibited
In order to transfer a domain name away from another provider, or to make changes to the whois or name servers, the lock must be removed.