nonmember professional
(2) For the purposes of this subsection, the term “nonmember professional” shall include (A) with respect to transactions in securities other than municipal securities, any registered broker or dealer who is not a member of any registered securities association, except such a broker or dealer who deals exclusively in commercial paper, bankers’ acceptances, and commercial bills, and (B) with respect to transactions in municipal securities, any municipal securities dealer (other than a bank or division or department of a bank) who is not a member of any registered securities association and any municipal securities broker who is not a member of any such association.