Japan 2026: Using the Trademark Consent Letter System, Practical Licensing & Enforcement Guide for Foreign Brands

The introduction of trademark consent letters in Japan has fundamentally changed how foreign brands navigate trademark clearance, coexistence and registration in one of Asia’s most commercially significant IP jurisdictions. On April 1, 2024, the revised Trademark Act took effect, formally enabling the Japan Patent Office (JPO) to accept Letters of Consent (LoCs) as part of the examination process for marks cited against prior registrations under Article 4(1)(xi). By April 7, 2025, METI announced the first trademark registration granted under the new consent letter system, and by December 1, 2025, the JPO had received 153 LoC-related applications, evidence that the mechanism is now operational and commercially consequential.

This guide provides in-house counsel, IP managers and brand licensing teams with a complete decision-to-execution playbook: when to use an LoC, how to draft one that passes JPO scrutiny, what licensing clauses to update, and how to enforce registered marks across Japan’s major online marketplaces.

Executive Summary and Decision Snapshot

For decades, Japan was one of the few major trademark jurisdictions that did not accept consent letters during examination. If a JPO examiner cited a prior similar mark as grounds for refusal under Article 4(1)(xi) of the Trademark Act, the applicant had no mechanism to submit a letter from the prior rights-holder consenting to coexistence. That changed with the revised Trademark Act Japan, which became effective on April 1, 2024. The reform aligned Japan more closely with the practice of the United States, the European Union and most other major filing jurisdictions.

The practical significance for foreign brands in 2026 is substantial. Industry observers expect the volume of LoC applications to accelerate as brand teams recognise the speed and cost advantages over oppositions, appeals and negotiated assignments. The first registration under the consent letter system Japan, announced by METI on April 7, 2025, demonstrated that the JPO is operationally ready to process LoCs. The 153 cumulative applications logged by December 1, 2025 suggest growing confidence among applicants and their counsel.

Before investing resources in an LoC strategy, brand teams should run through a quick decision checklist:

• Is the prior rights-holder identifiable and commercially reachable? An LoC requires their cooperation.
• Are the marks genuinely coexistence-compatible? The JPO retains discretion to refuse even with a consent letter if consumer confusion remains likely.
• Can the LoC be drafted with sufficient specificity? Generalised or blanket consents are not acceptable.
• Is there an existing commercial relationship (licensor–licensee, distributor, JV partner)? If so, embed LoC cooperation obligations into the licensing agreement.
• Has evidence of marketplace distinction been assembled? The JPO may consider evidence that the marks coexist without confusion.
• Is the cost-benefit favourable compared to opposition, appeal or assignment? LoCs are typically faster and less expensive, but preparation still requires legal counsel.

How Trademark Consent Letters Work in Japan: The Consent Letter System Explained

Statutory Basis and Timeline

The consent letter system Japan now operates under is anchored in the amendment to Article 4(1)(xi) of the Trademark Act, which governs refusals based on similarity to prior registered marks. Under the revised provision, an applicant may submit a Letter of Consent from the owner of the cited prior mark as part of the examination response. The JPO then evaluates the LoC alongside other factors to determine whether registration should proceed.

How the JPO Treats LoCs in Examination

A JPO consent letter does not guarantee registration. Examiners retain discretion to refuse an application even when a valid LoC is submitted, particularly where the marks are so similar, or the goods and services so closely related, that consumer confusion remains likely despite the prior owner’s consent. This discretionary model distinguishes Japan from jurisdictions where a consent letter creates a stronger presumption in favour of the applicant.

In practice, the JPO evaluates the following criteria when reviewing a submitted LoC:

• Specificity of consent. The LoC must identify the specific applied-for mark, the designated goods or services, and the prior registration number.
• Identity of the consenting party. The signatory must be the recorded owner of the cited prior mark (or an authorised representative with proof of authority).
• Absence of consumer confusion risk. The examiner independently assesses whether coexistence would cause confusion, taking into account the LoC, distinctiveness evidence and market conditions.
• Authenticity and completeness. A certified Japanese translation is expected for LoCs drafted in other languages, along with clear identification of all parties.

Decision Framework: When to Use a Consent Letter vs Alternatives

Trademark clearance Japan strategies must now include the LoC option in every cost-benefit analysis. However, an LoC is not always the best path. The decision depends on the commercial relationship between the parties, the degree of mark similarity, the strength of the prior mark and the urgency of registration. The table below compares the primary options available to foreign brand teams.

Can a Consent Letter Prevent Opposition or Cancellation?

An LoC submitted during examination addresses the Article 4(1)(xi) citation but does not immunise the resulting registration against post-registration challenges. A third party may still file an opposition within two months of the publication of registration, or seek cancellation on separate grounds such as non-use, fraud or public interest. The practical effect of an LoC, however, is that it removes the most common basis for refusal and signals to potential challengers that the prior owner endorses coexistence, which can discourage opportunistic oppositions.

How to Draft a Japan-Compliant Letter of Consent

Drafting an LoC that meets JPO requirements demands precision. A loosely worded or overly broad consent is likely to be disregarded or to invite an examiner’s request for clarification, delaying the application. The following section sets out the JPO checklist for acceptance and provides an annotated sample.

JPO Acceptance Checklist

Based on published JPO guidance and practitioner analysis, the following elements should be present in every LoC submitted to the JPO:

• Identification of the prior mark. Registration number, mark representation and designated goods/services of the cited prior registration.
• Identification of the applied-for mark. Application number (if available), the mark itself and the specific goods or services for which consent is given.
• Clear statement of consent. An unambiguous declaration that the prior owner consents to the registration and use of the applied-for mark for the specified goods/services.
• Identity and authority of signatory. Full legal name of the prior mark owner, corporate details where applicable, and evidence of signing authority if the signatory is not the registered owner personally.
• Date and signature. A signed and dated original (or certified copy) of the LoC.
• Certified Japanese translation. If the LoC is drafted in English or another language, a certified translation into Japanese should accompany the submission.

Are Generalised Consents Valid?

No. Both JPO guidance and comparative analysis by INTA confirm that a blanket consent, for example, “we consent to all future trademark registrations by [Applicant]”, is not acceptable. The LoC must be specific to the particular mark, designated goods/services and application at issue. Open-ended or generalised language lacks the precision needed for the examiner to assess confusion risk and may be treated as insufficient evidence of informed consent.

Sample Annotated Letter of Consent

The following is an illustrative LoC structure. It should be adapted by qualified counsel to the specific facts of each matter.

[Letterhead of Prior Mark Owner]

To: Commissioner, Japan Patent Office

Re: Consent to Registration of Trademark Application No. [●] filed by [Applicant Name]

We, [Full Legal Name of Prior Mark Owner], the registered owner of Japanese Trademark Registration No. [●] for the mark [●] covering [designated goods/services in Classes ●], hereby consent to the registration and use by [Applicant Full Legal Name] of the mark [●] as applied for under Application No. [●] for [specific goods/services in Classes ●].

We confirm that we do not consider that the coexistence of the two marks on the register for the respective goods/services identified above will give rise to consumer confusion.

[This consent is limited to the specific mark and goods/services identified above and does not extend to any other marks, goods, services or applications.]

Signed: ______ Name: ______ Title: ______ Date: ______

The bracketed limitation clause is particularly important. Omitting it may create an inference of broader consent than intended, which could complicate future enforcement or portfolio management.

Drafting Japan-Facing Trademark Licensing Clauses

Where the LoC arises from an existing or planned commercial relationship, the underlying trademark licensing Japan agreement should incorporate specific provisions that address consent letter mechanics, quality control and cross-border brand protection Japan considerations. The following twelve clauses are recommended for inclusion in any licence agreement that may involve LoC cooperation.

• Grant and territory. Define the licensed territory explicitly, Japan only, or Japan as part of an Asia-Pacific licence, and confirm that the grant includes the right to apply for registration.
• Scope by class, goods and services. Align the licensed goods/services precisely with the Nice Classification classes designated in the Japanese application to avoid scope disputes.
• Consent to registration / LoC mechanics. Obligate the licensor to provide a signed LoC in the form required by the JPO within a specified number of business days upon the licensee’s request, and to cooperate with translation and notarisation requirements.
• Coexistence and non-assertion. Include a narrow, specific non-assertion clause that mirrors the scope of the LoC, do not use open-ended language that could be exploited by third parties.
• Quality control and reservation of rights. Reserve the licensor’s right to approve the quality of goods and services sold under the licensed mark in Japan, consistent with JPO expectations regarding controlled use.
• Assignment and sub-licence restrictions. Specify whether the licensee may assign rights or grant sub-licences in Japan, and whether any such assignment triggers a new LoC obligation.
• Indemnity and costs for LoC / enforcement. Allocate costs of preparing, translating and submitting the LoC, and specify indemnification obligations for enforcement actions.
• Evidence and cooperation clause. Require both parties to preserve and share evidence of marketplace distinction, consumer surveys and use evidence that supports the LoC and any future enforcement actions.
• Jurisdiction and dispute resolution. Specify the governing law and forum, noting that Japan trademark enforcement actions may require Japanese court jurisdiction or JPO proceedings regardless of the contractual choice of law.
• Termination and effect on registrations. Address what happens to registrations obtained via LoC upon termination of the licence, does the LoC survive? Must the mark be assigned back?
• Confidentiality specific to LoC text. Consider whether the LoC text itself is confidential, given that it may become part of the public JPO file.
• IP portfolio audit and notice obligations. Require periodic audits of the licensed portfolio and prompt notice of any new filings, oppositions or third-party conflicts in Japan.

Sample clause, LoC cooperation: “Licensor shall, within fifteen (15) business days of Licensee’s written request, execute and deliver a Letter of Consent in a form acceptable to the Japan Patent Office, consenting to the registration of the Licensed Mark for the Licensed Goods/Services. Licensor shall cooperate with certified translation and any additional documentation reasonably required for JPO acceptance.”

Policing and Enforcing Your Brand Online in Japan

Securing registration, whether through an LoC or otherwise, is only the first step. Online brand enforcement Japan requires a structured, platform-by-platform policing programme. Japan’s e-commerce landscape is dominated by Amazon Japan, Rakuten, Yahoo! Auctions and Mercari, each of which operates its own intellectual property rights enforcement programme.

The recommended workflow for each platform follows a four-step pattern:

1. Identify the infringement. Monitor listings using brand monitoring tools, keyword alerts and periodic manual searches. Document every suspected infringing listing with date-stamped screenshots, URLs, seller identifiers and product images.
2. Preserve evidence. Before initiating any takedown request, capture a complete evidentiary record including the listing page, seller profile, pricing, product descriptions and any use of the registered mark in advertising or meta-tags.
3. Submit a rights assertion / takedown notice. Each platform has a designated IP enforcement portal or contact point. Provide the trademark registration number, evidence of infringement, and a clear statement that the listing infringes your registered rights.
4. Escalate if necessary. If the platform does not act or the seller re-lists, escalate to the platform’s legal team, engage local counsel, or consider court proceedings including provisional injunctions under Japan’s Civil Provisional Remedies Act.

Evidence Checklist for Marketplaces and JPO Purposes

Whether preparing evidence for marketplace takedowns or for submission to JPO examiners in support of an LoC or distinctiveness argument, the following items should be assembled and maintained on an ongoing basis:

• Date-stamped screenshots of infringing listings (full URL visible)
• ASIN, product ID or listing URL for each infringing item
• Seller identity and store name (as displayed on the platform)
• Chain of distribution evidence, purchase confirmations, packaging photographs, delivery documentation
• Trademark registration certificate (JPO-issued) and details of any LoC on file
• Consumer confusion evidence, customer complaints, misdirected enquiries, survey data if available

Using LoC Language as Enforcement Evidence

An LoC submitted during registration can serve a secondary enforcement purpose. The limitation clause in a well-drafted LoC delineates the scope of authorised coexistence. Any use by a third party that falls outside that scope can be cited as evidence that the infringing use was never authorised, strengthening the brand owner’s position in marketplace disputes and, if necessary, in court proceedings.

Enforcement Risks, Oppositions and Cancellation Interplay with LoCs

The consent letter system Japan has introduced is a powerful tool, but it has clear boundaries. The JPO may still refuse registration despite a valid LoC if the examiner concludes that consumer confusion is likely on the totality of the evidence. This is a substantive assessment, not a procedural formality, and it means that LoC submissions should always be accompanied by supporting evidence of market distinction.

Post-registration, the LoC does not eliminate opposition or cancellation risk. Third parties, not just the prior mark owner, may file oppositions within two months of publication, or seek cancellation on grounds such as non-use (after three consecutive years) or prior rights. The likely practical effect of an LoC, however, is twofold: it significantly reduces the risk of examiner refusal at the application stage, and it signals to potential challengers that the most obvious ground for objection has been addressed cooperatively.

Early adoption data supports cautious optimism. The METI announcement of the first LoC-based registration on April 7, 2025 confirmed that the system is functioning as intended. The 153 cumulative applications recorded by December 1, 2025 suggest steady uptake, although it remains early to draw conclusions about acceptance rates or examiner behaviour patterns. Industry observers expect the JPO to publish more detailed guidance as the case base grows through 2026.

Practical Workflows and Next Steps for Implementation

For foreign brand teams ready to operationalise the LoC system, the following 60–90 day implementation timeline provides a structured approach:

• Days 1–15: Audit. Review all pending and planned Japan trademark filings. Identify any applications cited against prior marks where an LoC could resolve the citation.
• Days 15–30: Outreach. Contact prior mark owners (or their counsel) to explore LoC cooperation. Where a licensing relationship exists, initiate amendment negotiations to add LoC cooperation clauses.
• Days 30–50: Drafting. Prepare LoCs in the format outlined above. Obtain certified Japanese translations. Assemble supporting evidence of marketplace distinction.
• Days 50–70: Submission. File the LoC with the JPO as part of the examination response. Monitor examiner feedback and respond to any requests for supplementary information.
• Days 70–90: Enforcement setup. Register marks on each major marketplace’s IP enforcement programme. Establish monitoring protocols and assign internal process owners for ongoing brand policing.

Teams that lack in-house Japan IP expertise should engage qualified Japanese trademark counsel to review all LoC drafts, licensing amendments and enforcement strategies before submission or execution.

Conclusion: Three-Point Action Plan for Foreign Brands

The trademark consent letters Japan framework is no longer theoretical, it is operational, tested and increasingly relied upon by brand owners and their counsel. Foreign companies with trademark portfolios touching Japan should take three immediate steps. First, audit all open Japan filings and clearance searches to identify applications where an LoC could resolve a prior-mark citation. Second, update trademark licensing agreements with explicit LoC cooperation clauses, certified translation obligations and evidence-sharing commitments. Third, operationalise an online enforcement programme across Amazon Japan, Rakuten, Yahoo! Auctions and Mercari, using the evidence checklist and workflow set out in this guide.

The brands that move earliest to integrate the consent letter system into their Japan IP strategy will secure faster registrations, stronger coexistence positions and more effective cross-border brand protection Japan outcomes.

Sources

1. Japan Patent Office (JPO), Trademark Law Guidance
2. METI, First Registration Under Consent System (April 7, 2025)
3. TMI Eyes, JPO Statistics on LoC Applications
4. Baker McKenzie InsightPlus, Japan Consent System Overview
5. Shiga Patent, Article 4(1)(xi) LoC Technical Requirements
6. INTA, How Letters of Consent Rules Diverge in Japan and South Korea
7. Asamura IP, Japan Trademark Consent System
8. Soei Patent, Introduction of Consent System