A registered practitioner may state or imply that the practitioner is a specialist as follows:
(a)
A registered practitioner who is an attorney may use the designation “Patents,” “Patent Attorney,” “Patent Lawyer,” “Registered Patent Attorney,” or a substantially similar designation.
(b)
A registered practitioner who is not an attorney may use the designation “Patents,” “Patent Agent,” “Registered Patent Agent,” or a substantially similar designation, except that any practitioner who was registered prior to November 15, 1938, may refer to himself or herself as a “patent attorney.”