Nominet requires that changes in domain ownership be handled between the Registrant and Nominet directly. Your Domain Provider can assist the Registrant, but Tucows itself does not get involved with this process.
The domain owner will need to complete the transfer form on the reverse of the Domain Name Certificate and submit a letter of authorization on company letterhead. Full instructions are given on the transfer form itself. In addition, the person or business the Registrant is transferring the Domain Name to must sign the form and submit a letter of authorization on their own letterhead. The two signatories of the letters must be different people.
If the domain owner has misplaced their Certificate for the Domain Name, and they want to transfer the registration to another holder, they may request a transfer form from Nominet at http://www.nic.uk. Please contact them directly via nominet@nominet.org.uk for the correct procedure.