(b) Persons subject to prohibition The persons subject to the prohibition under subsection (a) are any lobbyist that is registered or is required to register under section
1603 (a)(1) of this title, any organization that employs 1 or more lobbyists and is registered or is required to register under section
1603 (a)(2) of this title, and any employee listed or required to be listed as a lobbyist by a registrant under section
1603 (b)(6) or
1604 (b)(2)(C) of this title.