(1) Members of the Boards of Appeal or of the Enlarged Board of Appeal may not take part in a case in which they have any personal interest or if they have previously been involved as representatives of one of the parties, or if they participated in the decision under appeal.
(2) If, for one of the reasons mentioned in paragraph 1, or for any other reason, a member of a Board of Appeal or of the Enlarged Board of Appeal considers that he should not take part in any appeal, he shall inform the Board accordingly.
(3) Members of a Board of Appeal or of the Enlarged Board of Appeal may be objected to by any party for one of the reasons mentioned in paragraph 1, or if suspected of partiality. An objection shall not be admissible if, while being aware of a reason for objection, the party has taken a procedural step. An objection may not be based upon the nationality of members.
(4) The Boards of Appeal and the Enlarged Board of Appeal shall decide as to the action to be taken in the cases specified in paragraphs 2 and 3 without the participation of the member concerned. For the purposes of taking this decision the member objected to shall be replaced by his alternate.