Overview
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On 30 September 2025, the UK's Competition and Markets Authority (CMA) and the Fair Trade Commission of Japan (JFTC) signed a Memorandum of Cooperation (MoC) establishing a framework to promote cooperation, coordination, and the exchange of information in relation to their competition law enforcement activities. The MoC reflects the growing importance of bilateral cooperation in an increasingly globalised marketplace, particularly in areas such as digital platforms and complex multinational mergers.
This article covers a summary of the MoC focusing on the three key areas of cooperation (i.e. notification, coordination of enforcement activities and information sharing), areas of differences with other agreements, and implications for business.
Key Areas of Cooperation
Notification
Where one authority becomes aware of enforcement activities that may affect the "important interests" of the other, it should provide notification to the other as soon as reasonably practicable. One authority should also notify the other whenever it intervenes or otherwise participates in a regulatory or judicial proceeding if the issues addressed in the intervention or participation may affect the other's "important interests."
A notification should include sufficient detail to enable the other to make an initial evaluation of the effect of the enforcement activity on its own important interests. Where applicable, such detail may include: the name and address of any enterprise subject to the enforcement activity; a description of the conduct or transaction subject to the enforcement activity; and the legal provision concerned.
Coordination of enforcement activities
One authority may render assistance to the other in its enforcement activities. Where both authorities have an interest in pursuing enforcement activities in related matters, they may decide to coordinate their enforcement activities. When carrying out coordinated enforcement activities, each authority will consider the importance of the other's enforcement objectives. One authority may limit or terminate the coordination and pursue its enforcement activities independently at any time.
Information sharing
Both authorities acknowledge that it is in their common interest to share and discuss views and to communicate information including investigative information in order to facilitate the application of their competition laws and to promote a better understanding of each other's enforcement activities and policies.
One authority may make a written request for information to the other, in relation to:
- The subject-matter and nature of the enforcement activity concerned;
- The legal provisions involved;
- The information sought;
- The purpose for which the information is sought; and
- Details of any reasonably foreseeable disclosure obligations on the requesting authority.
The authority that receives a request for information will determine, in discussion with the requesting authority, which information in its possession is relevant and may be communicated to the other. The authority communicating information may communicate the information dependent on additional conditions. Where one authority becomes aware that information provided under the MoC contains incorrect information, it will inform the other as soon as reasonably practicable and take corrective measures.
There are also restrictions on the types of information that may be shared or communicated. An authority may transfer personal data only in accordance with its national laws. The CMA does not expect to transfer personal data save in exceptional and specific circumstances. Further, the authorities will not communicate information obtained under an immunity or leniency application or an admission of liability obtained in a settlement procedure or any documents provided to support that admission, without the natural or legal person's written consent to provide such information.
In addition to the above areas of cooperation, the MoC also sets out a confidentiality framework under which the authorities will maintain the confidentiality of any information communicated from one authority to the other, including the fact that a request for information has been made or received, and oppose any request by a third party for disclosure of that information.
While the confidentiality framework is in place, the MoC permits lawful disclosures of information, which include disclosures by a court order or in the course of judicial review or appeal proceedings in relation to enforcement activity, though commercially sensitive information and any personal data (discussed above) remain protected to the fullest extent permitted under its national law. Information may also be provided from one authority to the other with a confidentiality waiver.
Differences
Until today, the JFTC has executed agreements concerning cooperation on anti-competitive activities with the European Community (signed in 2003), the US and Canada, as well as memorandums of understanding on cooperation with competition authorities with India, Singapore, and other countries.
We set out below some differences between this MoC and the Agreement between the Government of Japan and the European Community Concerning Cooperation on Anticompetitive Activities, which had been applied prior to Brexit (EC Agreement). It is worth noting that the contents of the agreements with the US and Canada are mostly similar to the EC Agreement.
Format and scope of cooperation
A major difference concerns formality and legal effect. The EC Agreement is made in the form of a treaty and thus legally binding, whereas the MoC is only a memorandum of understanding and not legally binding, subject to obligation to make efforts. In addition, although the EC Agreement covers information exchange related to criminal enforcement activities, the MoC clearly excludes such information exchange and rather focuses on that is related to enforcement activities including investigative information.
Notification
Both the MoC and the EC Agreement have a similar provision in relation to the sharing of information on enforcement activities including investigations and merger filings and reviews. However, there are some provisions in the MoC that are designed specifically to facilitate merger filings.
Paragraph 4 (3) of MoC stipulates that "the Participants are not expected to notify each other during the pre-notification stage of the proceedings" but that "notification under this paragraph will ordinarily be given as soon as reasonably practicable after a Participant becomes aware that notifiable circumstances are present". The number of merger filing and review cases which the JFTC collaborate with overseas authorities has been on the rise in recent years, and such provision is understood to be included in order to facilitate smoother and more effective bilateral collaboration.
The voluntary nature of the UK's regime, together with the limited requirement to share information only after formal notification, may result in a ‘grey area' in scenarios where the CMA reviews a merger using its merger intelligence functions (including in response to a briefing note), but does not require a formal notification. This could give rise to a conflict where the JFTC does proceed to review the merger (since under the MOU the CMA would not be required to consult or inform the JFTC before deciding ‘not' to investigate).
Coordination and assistance of enforcement activities
Both the MoC and the EC Agreement have similar provisions regarding provision of assistance in their respective enforcement activities. That said, there is one noticeable difference, relating to requests for enforcement actions. Article 5 of the EC Agreement stipulates that the competition authority of a Party "may request that the competition authority of the other initiate appropriate enforcement activities" if the former authority believes anti-competitive activities carried out in the territory of the other adversely affect important interests of the requesting authority. The MoC on the other hand does not contain such a 'request' provision.
In cartel investigations, it is quite likely that a competition authority may need to be able to request enforcement because it is generally the authorities which will initiate a formal investigation. But in merger cases (although competition authorities may initiate an investigation without waiting for parties' filings), it is usually the parties to the transaction which are the ones to notify the authorities in jurisdictions where the proposed transactions qualify for review. It is likely that such ‘request' provision is not included in the MoC since it puts more weight on merger filing cases.
Communication of information and policy
Both the MoC and the EC Agreement contain provisions that are premised on the exchange of information on enforcement activities and policies. The EC Agreement stipulates such discussions and information exchanges in Article 8 and the procedure for information exchange in a relatively simple way in Article 9, while the MoC stipulates such information exchanges and procedures in more detail in paragraphs 7 to 9.
Implications and Practical Tips for Businesses and Legal Practitioners
Even though the MoC is not legally binding, as discussed above, its purpose is to promote bilateral cooperation and coordination. Businesses active in both jurisdictions should assume that conduct attracting the attention of one authority could readily draw the other into the picture.
While the MoC does not mandate joint cases, it expressly provides for coordination of enforcement activities. For businesses, this creates a scenario where investigations into cartels, abuse of dominance cases or mergers may be coordinated in terms of timing and information sharing. The implications are significant in that parallel investigations may be started around the same time. Coordinated investigations could also lead to the CMA and JFTC sharing non-confidential information or requesting aligned disclosure.
In merger control, parallel filings are likely to involve closer communication between the authorities as they are committed to information sharing where domestic law allows. While commercially sensitive information may remain protected, the MoC creates more avenues for the transfer of case theories and economic evidence. Legal practitioners should ensure that data and arguments presented to the CMA and JFTC do not conflict. Discrepancies between filings, market definitions and analyses, or competitive assessments may be spotted if they exchange views. Furthermore, in scenarios of dual notification to both the JFTC and CMA, parties may wish to consider providing confidentiality waivers to allow discussion between the two authorities. If these are not proffered, the agencies may nonetheless request them.
Although outcomes will still depend on their respective competition laws, parties should anticipate that the authorities may also discuss remedies or behavioural commitments with each other. Where a remedy is available, counsel should consider how it would play in both jurisdictions.
Conclusions
The MoC is a meaningful step towards more active UK-Japan antitrust collaboration. For cross-border businesses, it offers an improved foundation for mutual assistance, earlier alignment, and better risk management. It is notable, for example, that "important interests" is not defined.
Key tips for businesses that are in mergers, parties will need to be careful to have market definitions and analyses which are consistent across jurisdictions. In investigations, parties will need to consider carefully the impact of disclosures in one jurisdiction, on investigations taking place in the other and to coordinate any immunity or leniency submissions to best protect the undertaking.
