(1) An attorney or agent registered to practice before the Office in patent matters;
(2) An individual authorized under 5 U.S.C. 500(b), or otherwise as provided by § 11.14(a), (b), and (c), to practice before the Office in trademark matters or other non-patent matters;
(3) An individual authorized to practice before the Office in a patent case or matters under § 11.9(a) or (b); or
(4) An individual authorized to practice before the Office under § 11.16(d).
37 CFR § 11.1
This part governs solely the practice of patent, trademark, and other law before the United States Patent and Trademark Office. Nothing in this part shall be construed to preempt the authority of each State to regulate the practice of law, except to the extent necessary for the United States Patent and Trademark Office to accomplish its Federal objectives. Unless otherwise clear from the context, the following definitions apply to this part: