29 CFR 102.129: Communications prohibited.

Except as provided in § 102.130, ex parte communications prohibited by § 102.126 include:

(a) Such communications, when written, if copies are not contemporaneously served by the communicator on all parties to the proceeding in accordance with the provisions of § 102.5(g).

(b) Such communications, when oral, unless advance notice is given by the communicator to all parties in the proceeding and adequate opportunity afforded to them to be present.