# 民事訴訟法 / Code of Civil Procedure — 第四十五条 (Article 45)

- Law: 民事訴訟法 (Code of Civil Procedure), 平成八年法律第百九号
- English title "Code of Civil Procedure": Ministry of Justice translation
- Kind: Act — the distinction between 法律 (Act), 政令 (Cabinet Order), 省令 (Ministerial Order) and 条例 (local ordinance) decides who may issue it and what it may say.
- Provision: 第四十五条 (Article 45)（補助参加人の訴訟行為等） — address `art-45`
- Text in force since: 2026-06-24
- URL (the page that opens at this provision): https://japanlaw.org/en/code-of-civil-procedure/art-45
- Permanent URL (e-Gov law ID, never renamed): https://japanlaw.org/l/408AC0000000109/art-45
- Every provision below carries its address and both URLs on the line under it.
- Japanese text: e-Gov 法令検索, Digital Agency (デジタル庁). English: as marked on each line below.

Only the Japanese as published by the government has legal effect; the text
below is a copy of it. Every English rendering below is a translation and
says which kind: the Ministry of Justice's translation, or this
site's machine translation, whose model and date the Sources list names.
They are never merged and never substituted for one another.

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### 第四十五条（補助参加人の訴訟行為等） — (Procedural Acts by a Supporting Intervener)
<sup>caption: Ministry of Justice translation — Japanese Law Translation Database System</sup>
<sup>art-45 · https://japanlaw.org/en/code-of-civil-procedure/art-45 · https://japanlaw.org/l/408AC0000000109/art-45</sup>

    **第一項**  補助参加人は、訴訟について、攻撃又は防御の方法の提出、異議の申立て、上訴の提起、再審の訴えの提起その他一切の訴訟行為をすることができる。ただし、補助参加の時における訴訟の程度に従いすることができないものは、この限りでない。
    <sup>art-45/par-1 · https://japanlaw.org/en/code-of-civil-procedure/art-45/par-1 · https://japanlaw.org/l/408AC0000000109/art-45/par-1</sup>
    A supporting intervener may present allegations and evidence, file an objection, file an appeal, file a demand for a retrial, or perform any other procedural act in the litigation in question; provided, however, that this does not apply to procedural acts that the supporting intervener may not perform due to the progress of the litigation at the time of the supporting intervention.
    <sup>Ministry of Justice translation — Japanese Law Translation Database System</sup>

    **第二項**  補助参加人の訴訟行為は、被参加人の訴訟行為と抵触するときは、その効力を有しない。
    <sup>art-45/par-2 · https://japanlaw.org/en/code-of-civil-procedure/art-45/par-2 · https://japanlaw.org/l/408AC0000000109/art-45/par-2</sup>
    A procedural act performed by a supporting intervener is invalid if it conflicts with a procedural act performed by the party being supported in the intervention.
    <sup>Ministry of Justice translation — Japanese Law Translation Database System</sup>

    **第三項**  補助参加人は、補助参加について異議があった場合においても、補助参加を許さない裁判が確定するまでの間は、訴訟行為をすることができる。
    <sup>art-45/par-3 · https://japanlaw.org/en/code-of-civil-procedure/art-45/par-3 · https://japanlaw.org/l/408AC0000000109/art-45/par-3</sup>
    Even if an objection has been raised against a supporting intervention, a supporting intervener may perform procedural acts until a judicial decision disallowing the supporting intervention becomes final and binding.
    <sup>Ministry of Justice translation — Japanese Law Translation Database System</sup>

    **第四項**  補助参加人の訴訟行為は、補助参加を許さない裁判が確定した場合においても、当事者が援用したときは、その効力を有する。
    <sup>art-45/par-4 · https://japanlaw.org/en/code-of-civil-procedure/art-45/par-4 · https://japanlaw.org/l/408AC0000000109/art-45/par-4</sup>
    A procedural act performed by a supporting intervener is valid if invoked by a party, even if a judicial decision disallowing the supporting intervention becomes final and binding.
    <sup>Ministry of Justice translation — Japanese Law Translation Database System</sup>

    **第五項**  次に掲げる請求に関する規定の適用については、補助参加人（当事者が前条第一項の異議を述べた場合において補助参加を許す裁判が確定したもの及び当事者が同条第二項の規定により異議を述べることができなくなったものに限る。）を当事者とみなす。
    <sup>art-45/par-5 · https://japanlaw.org/en/code-of-civil-procedure/art-45/par-5 · https://japanlaw.org/l/408AC0000000109/art-45/par-5</sup>
    To apply provisions that concern the following requests, a supporting intervener (limited to one whose intervention is permitted by a judicial decision that has become final and binding after the party has raised the objection referred to in paragraph (1) of the preceding Article; or to one against whose intervention the party is no longer entitled to raise an objection pursuant to the provisions of paragraph (2) of that Article) is deemed to be a party:
    <sup>Ministry of Justice translation — Japanese Law Translation Database System</sup>

      **一**  非電磁的訴訟記録（第九十一条第一項に規定する非電磁的訴訟記録をいう。）の閲覧若しくは謄写、その正本、謄本若しくは抄本の交付又はその複製（第九十二条第一項において「非電磁的訴訟記録の閲覧等」という。）の請求
      <sup>art-45/par-5/item-1 · https://japanlaw.org/en/code-of-civil-procedure/art-45/par-5/item-1 · https://japanlaw.org/l/408AC0000000109/art-45/par-5/item-1</sup>
      a request to inspect or copy hard-copy case records (meaning hard-copy case records as provided in Article 91, paragraph (1)), or to be issued an authenticated copy, transcript, or extract of those records, or for those records to be reproduced (referred to as "access to hard-copy case records" in Article 92, paragraph (1));
      <sup>Ministry of Justice translation — Japanese Law Translation Database System</sup>

      **二**  電磁的訴訟記録（第九十一条の二第一項に規定する電磁的訴訟記録をいう。）の閲覧若しくは複写又はその内容の全部若しくは一部を証明した書面の交付若しくはその内容の全部若しくは一部を証明した電磁的記録の提供（第九十二条第一項において「電磁的訴訟記録の閲覧等」という。）の請求
      <sup>art-45/par-5/item-2 · https://japanlaw.org/en/code-of-civil-procedure/art-45/par-5/item-2 · https://japanlaw.org/l/408AC0000000109/art-45/par-5/item-2</sup>
      a request to inspect or copy electronic or magnetic case records (meaning electronic or magnetic case records as prescribed in Article 91-2, paragraph (1)), to be issued a paper document certifying the whole or part of their content, or to be provided with electronic or magnetic records certifying the whole or part of their content (referred to as "access to electronic or magnetic case records" in Article 92, paragraph (1)); and
      <sup>Ministry of Justice translation — Japanese Law Translation Database System</sup>

      **三**  第九十一条の三に規定する訴訟に関する事項を証明した書面の交付又は当該事項を証明した電磁的記録の提供の請求
      <sup>art-45/par-5/item-3 · https://japanlaw.org/en/code-of-civil-procedure/art-45/par-5/item-3 · https://japanlaw.org/l/408AC0000000109/art-45/par-5/item-3</sup>
      a request to issue a paper document certifying information concerning the litigation as prescribed in Article 91-3, or to provide electronic or magnetic records certifying that information.
      <sup>Ministry of Justice translation — Japanese Law Translation Database System</sup>

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## Cites
- art-45/par-5: 前条第一項 → 民事訴訟法 第四十四条第一項 (Article 44, paragraph (1)), art-44/par-1 — https://japanlaw.org/en/code-of-civil-procedure/art-44/par-1 · https://japanlaw.org/l/408AC0000000109/art-44/par-1
- art-45/par-5: 同条第二項 → 民事訴訟法 第四十四条第二項 (Article 44, paragraph (2)), art-44/par-2 — https://japanlaw.org/en/code-of-civil-procedure/art-44/par-2 · https://japanlaw.org/l/408AC0000000109/art-44/par-2
- art-45/par-5/item-1: 第九十一条第一項 → 民事訴訟法 第九十一条第一項 (Article 91, paragraph (1)), art-91/par-1 — https://japanlaw.org/en/code-of-civil-procedure/art-91/par-1 · https://japanlaw.org/l/408AC0000000109/art-91/par-1
- art-45/par-5/item-1: 第九十二条第一項 → 民事訴訟法 第九十二条第一項 (Article 92, paragraph (1)), art-92/par-1 — https://japanlaw.org/en/code-of-civil-procedure/art-92/par-1 · https://japanlaw.org/l/408AC0000000109/art-92/par-1
- art-45/par-5/item-2: 第九十一条の二第一項 → 民事訴訟法 第九十一条の二第一項 (Article 91-2, paragraph (1)), art-91-2/par-1 — https://japanlaw.org/en/code-of-civil-procedure/art-91-2/par-1 · https://japanlaw.org/l/408AC0000000109/art-91-2/par-1
- art-45/par-5/item-2: 第九十二条第一項 → 民事訴訟法 第九十二条第一項 (Article 92, paragraph (1)), art-92/par-1 — https://japanlaw.org/en/code-of-civil-procedure/art-92/par-1 · https://japanlaw.org/l/408AC0000000109/art-92/par-1
- art-45/par-5/item-3: 第九十一条の三 → 民事訴訟法 第九十一条の三 (Article 91-3), art-91-3 — https://japanlaw.org/en/code-of-civil-procedure/art-91-3 · https://japanlaw.org/l/408AC0000000109/art-91-3

## Cited by

6 provisions cite this one. No official source publishes this direction.

- 民事執行法 別表第二 — https://japanlaw.org/en/civil-enforcement-act/appdx-2 · https://japanlaw.org/l/354AC0000000004/appdx-2
- 民事訴訟法 第四十六条第一項第一号（補助参加人に対する裁判の効力） — https://japanlaw.org/en/code-of-civil-procedure/art-46/par-1/item-1 · https://japanlaw.org/l/408AC0000000109/art-46/par-1/item-1
- 民事訴訟法 第四十六条第一項第二号（補助参加人に対する裁判の効力） — https://japanlaw.org/en/code-of-civil-procedure/art-46/par-1/item-2 · https://japanlaw.org/l/408AC0000000109/art-46/par-1/item-2
- 行政事件訴訟法 第二十二条第五項（第三者の訴訟参加） — https://japanlaw.org/en/administrative-case-litigation-act/art-22/par-5 · https://japanlaw.org/l/337AC0000000139/art-22/par-5
- 行政事件訴訟法 第二十三条第三項（行政庁の訴訟参加） — https://japanlaw.org/en/administrative-case-litigation-act/art-23/par-3 · https://japanlaw.org/l/337AC0000000139/art-23/par-3
- 行政事件訴訟法 第四十五条第二項（処分の効力等を争点とする訴訟） — https://japanlaw.org/en/administrative-case-litigation-act/art-45/par-2 · https://japanlaw.org/l/337AC0000000139/art-45/par-2

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## Sources

- e-Gov 法令検索, Digital Agency (デジタル庁) — 民事訴訟法 — the text in force from 2026-06-24 (https://laws.e-gov.go.jp/law/408AC0000000109/20260624_508AC0000000046), retrieved 2026-10-17
- Japanese Law Translation Database System, Ministry of Justice (法務省) — Code of Civil Procedure — Ministry of Justice translation (https://www.japaneselawtranslation.go.jp/en/laws/view/4797/tb), retrieved 2026-10-17
- This site's parser, version 209 — 民事訴訟法 — structure, counts, cross-references and defined terms, computed 2026-10-17