(a) It is unlawful for the Commissioner or any of the officers or employees in the Division of Securities to use for personal benefit any information which is filed with or obtained by the Commissioner and which is not made public.
(b) No provision of this title authorizes the Commissioner or any of his officers or employees to disclose any such information except among themselves or when necessary or appropriate in a proceeding or investigation under this title.
(c) No provision of this title either creates or derogates from any privilege which exists at common law or otherwise when documentary or other evidence is sought under a subpoena directed to the Commissioner or any of his officers or employees.