12 C.F.R. § 1080.14 – Confidential treatment of demand material and non-public nature of investigations.

(a) Documentary materials, written reports, answers to questions, tangible things or transcripts of oral testimony the Bureau receives in any form or format pursuant to a civil investigative demand are subject to the requirements and procedures relating to the disclosure of records and information set forth in part 1070 of this title.
(b) Bureau investigations generally are non-public. Bureau investigators may disclose the existence of an investigation to potential witnesses or third parties to the extent necessary to advance the investigation.