The Anti-Monopoly Act (“AMA”), Japan’s competition law, went through a major change which came into effect at the end of 2020. In response to continuous pressure from the Japanese business community and the Japanese bar, the amendment introduced protection for communication between attorneys and clients for the first time in Japanese legislation, albeit in very limited form compared to the “attorney-client privilege” recognized in common law jurisdictions. This article explains what in-house counsel should know to protect a company’s legal document under the new rule in antitrust cases.


Communication regarding non-antitrust subjects continues not to be protected under the Japanese law, and the protection in the new rule limits scope in the following ways:

First, in-house counsel should understand that the AMA only protects legal advice in confidence when it is regarding conduct which may be subject to leniency applications under the AMA (i.e. hard-core cartels). Legal advice regarding other subjects, such as private monopolization and other types of single-firm conduct, will not be protected under the rule.

Second, communication on facts will not be covered under this rule. As a result, documents such as interview memoranda, which only describe facts, will not be protected.

Moreover, the rule in principle does not cover communication between in-house counsel and their internal clients. Thus, outside counsel must be involved to be eligible for protection. In-house counsel in multinational corporations should also know that the rule does not protect communication that does not include a Japanese-qualified attorney, so a Japanese-qualified attorney must be involved in the communication.


In addition to limitation on the scope of the protected communication, the rule also imposes strict requirements on how the covered communication must be retained inside the company, such as the following:

The rule requires that the covered communication must be “properly stored” by the company. The covered communication must be labelled as protected documents and be easily recognized from the outside. In-house counsel should be aware that the rule requires very specific methods for labelling the documents. Though it may be surprising to many in-house counsel, the label “attorney-client privilege” will not suffice. Specific wording (some-thing like “公取審査規則特定通信” in Japanese) needs to be used for labelling.

The rule also provides that the protected communication must be stored with divisions that have authority inside the company to consult with outside attorneys. In most companies this means the legal department or general counsel office, but some multinational companies with only small operations in Japan do not have an internal legal division in Japan, in which case the company should consider how and where the protected documents need to be stored on a case-by-case basis.

Also, the communication needs to be in confidence and shared only on a “need-to-know” basis inside the company for it to be protected.


The Japan Fair Trade Commission (“JFTC”) published detailed guidelines and Q&As regarding how it applies the new rule to protected communication that I cannot fully explain due to the limited length of this article. Because the consequences of non-compliance with these rules may be grave in the case of a JFTC investigation, it is recommended that in-house counsel review and revise their companies’ document retention policy by consulting with an experienced antitrust lawyer in Japan to prevent the company’s legal documents from being seized by the JFTC.



日本の競争法である独占禁止法の改正法が昨年12月に施行された。経済界及び弁護士会からの継続的な要請等を踏まえ、コモンロー諸国におけるいわゆる「弁護士依頼者間秘匿特権(Attorney-client privilege)」と比較するとかなり限定的ではあるものの、同改正において弁護士と依頼者との間の通信内容を保護する制度(以下「本制度」という。)が導入された。本稿では、紙面の都合上、独占禁止法事案において社内の法的文書を保護するためにインハウス弁護士が理解しておくべきポイントに絞って解説する。







本制度上、保護となる通信を含む物件は「適切に保管」されている必要がある。例えば、対象となる物件には保護の対象であることが外部から識別できるよう表示がなされている必要がある。当該表示のための文言について、本制度上、欧米でよく用いられる「弁護士依頼者秘匿特権(Attorney-client privilege)」という表示文言は認められず、「公取審査規則特定通信」といった本制度特有の表示を付す必要があることに留意しなければならない。




限られた紙面の都合上すべてを紹介できないが、公正取引委員会は、本制度の運用についての詳細を定める指針(https://www.jftc.go.jp/dk/kaisei/r1kaisei/index_file s/07hanbetu.pdf)及びQ&A(https://w ww.jftc. go.jp/dk/kaisei/r1kaisei/qa/qa.html#cmsQ101)を公表している。これらに従わなかった場合、公正取引委員会による調査において弁護士との通信記録が保護されないという重大な帰結を伴う可能性があるため、インハウス弁護士は、独占禁止法専門弁護士のアドバイスの下、所属企業における文書管理規程やその運用を見直し、本制度に基づく保護を可能な限り受けられるようにしておくべきであろう。


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