A judicial decision in litigation that involves a supporting intervention is also effective against the supporting intervener, except in the following cases:
補助参加に係る訴訟の裁判は、次に掲げる場合を除き、補助参加人に対してもその効力を有する。
if the supporting intervener is unable to perform a procedural act, pursuant to the provisions of the proviso to paragraph (1) of the preceding Article;
前条第一項ただし書の規定により補助参加人が訴訟行為をすることができなかったとき。
if a procedural act by the supporting intervener is invalid, pursuant to the provisions of paragraph (2) of the preceding Article;
前条第二項の規定により補助参加人の訴訟行為が効力を有しなかったとき。
if the party being supported in the intervention interferes with a procedural act by the supporting intervener;
被参加人が補助参加人の訴訟行為を妨げたとき。
if the party being supported in the intervention intentionally or negligently fails to perform a procedural act that a supporting intervener is not permitted to perform.
被参加人が補助参加人のすることができない訴訟行為を故意又は過失によってしなかったとき。
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