According to Nominet, registrants of .com, .org and, most recently, .uk domain names have been receiving a "Notice of Expiration" invoice from Domain Registry Services, which infers that it is the Registry for those domains – which it is not.
The notice states that the registrant could lose its domain name unless the invoice is paid – at a cost many times higher than that Nominet would charge a domain registration agent for registering a .uk domain name.
Nominet advises all .uk domain holders "to be careful when checking correspondence regarding the expiry of their domain names. If you have any doubts about the validity of an invoice, please contact your existing registration agent who will be able to advise you."
The Registry is also investigating where Domain Registry Services obtained its lists of .uk information, and is working with trading standards officers.