Hi,
I am sorry, but I do not understand what you mean when you say 'obligated to confirm data protection'. Professional confidentialty, however, certainly applies.
Your client records should be held confidential except to another veterinary suregon who is taking over a case, and with the animal owner's permission calls the previous vet for details of the case records.
If there has been a clear case of breach of confidentialty and you feel sufficiently strongly about it you should file a complaint with the RCVS (www.rcvs.org.uk)
W