When an immediate appeal is filed against a ruling, the court in charge of the appeal must send a copy of a petition for appeal to the party and interested party intervenor in the prior instance (excluding the appellant), except when the immediate appeal is unlawful or the immediate appeal is clearly groundless; provided, however, that if it is found that there is a risk of interfering with the smooth progress of proceedings in the instance of an appeal, the court in charge of the appeal may give notice to those parties of the fact that an immediate appeal is filed, in lieu of sending a copy of a petition for appeal.
審判に対する即時抗告があった場合には、抗告裁判所は、即時抗告が不適法であるとき又は即時抗告に理由がないことが明らかなときを除き、原審における当事者及び利害関係参加人（抗告人を除く。）に対し、抗告状の写しを送付しなければならない。ただし、抗告審における手続の円滑な進行を妨げるおそれがあると認められる場合には、即時抗告があったことを通知することをもって、抗告状の写しの送付に代えることができる。
When the presiding judge specifies a reasonable period and orders an appellant to prepay costs for sending a copy of a petition for appeal or giving notice in lieu of sending the copy under the provisions of the preceding paragraph, but the costs are not prepaid, the presiding judge must, by a direction, dismiss the petition for appeal.
裁判長は、前項の規定による抗告状の写しの送付又はこれに代わる通知の費用の予納を相当の期間を定めて抗告人に命じた場合において、その予納がないときは、命令で、抗告状を却下しなければならない。
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interested party intervenor
「利害関係参加人」
A person who has joined proceedings for adjudication of domestic relations (家事審判) under Article 42, paragraphs (1) to (3) — as a person who is to be subject to the ruling, or, with the family court's permission or by its order, as a person directly affected by its outcome or qualified to be a party — and who may then perform most of the procedural acts a party can.
Short name set inArticle 42, paragraph (7)