Legal Strategies for Design Patent Infringement Claims on Amazon: Key Points for Similarity Assessment and Business Risk Management

According to the “Market Survey on Electronic Commerce for Fiscal Year Reiwa 6 (2025)” published by the Ministry of Economy, Trade and Industry in August 2025, the e-commerce (EC) market in Japan is on a continuous growth trajectory. The BtoC-EC market size has increased by 5.1% from the previous year, reaching 26.1 trillion yen, while the BtoB-EC market size has grown by 10.6%, reaching 514.4 trillion yen. Notably, the EC conversion rate in the merchandise sector has risen to 9.78%, with more than half of transactions in specific categories such as books, videos, and electronics shifting online. This structural shift towards a digital economy has established EC platforms like Amazon Japan (Amazon.co.jp) as essential social infrastructure, beyond merely being sales channels.

However, alongside this convenience, disputes over intellectual property rights have intensified. Particularly, allegations of design rights infringement pose a significant risk to business continuity, as they can lead to immediate adverse actions such as “listing suspensions” without awaiting judicial decisions. Under the Japanese legal system, especially the Japanese Design Act, “aesthetic appeal through visual perception” is protected, requiring a high level of expertise and logical reasoning for determining similarity (whether designs are alike).

This article explains the intellectual property risks associated with EC platforms and provides a detailed discussion on legal strategies and practical countermeasures for intellectual property, using cases of design rights infringement claims on Amazon Japan as examples.

For a detailed explanation of false intellectual property infringement claims on Amazon Japan, please refer to the article below.

Expansion of the E-commerce Market and the Structural Background of Intellectual Property Disputes in Japan

With the expansion of the e-commerce market, the ability to sell on e-commerce platforms has become a source of competitive advantage for businesses in Japan. In this vast market, platforms like Amazon Japan (Amazon.co.jp) operate intellectual property protection systems such as the “Brand Registry” and “Infringement Report Form.” While these systems serve as powerful tools for rights holders to swiftly eliminate counterfeit products, they also pose significant risks for sellers who receive claims. These sellers may face severe disadvantages, such as “listing suspension” or “account suspension,” before any legal examination of whether the rights are being exercised legitimately.

Design rights, alongside patent rights and trademark rights, are powerful rights that allow for the exclusive use of a product’s design. Article 23 of the Japanese Design Act stipulates that “the holder of a design right shall have the exclusive right to work the registered design and any design similar thereto as a business.” While patent rights protect technical ideas, design rights protect “shapes that evoke aesthetic appeal through visual perception,” making the determination of infringement heavily dependent on “the impression perceived by human vision.” This subjective element in the process of determining similarity is at the core of infringement disputes on Amazon Japan.

Mechanism of Intellectual Property Infringement Claims and Adverse Actions on Amazon Japan

Disputes over intellectual property on Amazon Japan progress with a unique speed and logic, distinct from ordinary civil litigation in Japanese courts. When a rights holder reports a specific ASIN (Amazon Standard Identification Number) as an infringing product, Amazon Japan independently decides to immediately remove the listing or restrict inventory.

When an infringement claim is accepted in Amazon Japan’s system, sellers face a variety of risks, as outlined below.

These actions are autonomously executed by Amazon Japan and do not require provisional injunctions under Japanese Civil Procedure Law. Therefore, to counter unjust claims, it is necessary to promptly submit “legal evidence-based non-infringement proof” to the platform.

Legal Understanding of Japanese Design Rights and Basic Principles of Similarity Assessment

To determine whether there is an infringement of design rights under Japanese law, it is essential to accurately understand the concept of “similarity” as defined in the Japanese Design Act. Article 24, Paragraph 2 of the Design Act clearly states that the judgment of whether a registered design and another design are similar is based on the aesthetic impression they create through the consumer’s visual perception.

Definition and Scope of Protection of Designs

According to Article 2, Paragraph 1 of the Japanese Design Act, a design refers to “the shape, patterns, or colors of an article, or a combination thereof, which creates an aesthetic impression through visual perception.” The strong exclusivity of design rights extends not only to identical items that match the registered design exactly but also to those within the scope of “similarity.”

In practice, the assessment of design similarity is conducted through the following three steps:

1. Recognition of Identity or Similarity of Articles: Confirm whether the articles related to the design are identical or similar. If the articles are dissimilar (for example, a “chair” and a “spoon”), even if their shapes are similar, design rights infringement does not occur.
2. Recognition of Structural Features: Extract both the basic structure (overall framework) and specific structure (details of shape and decoration) of the designs.
3. Evaluation of Commonalities and Differences: Identify the commonalities and differences between the designs and comprehensively assess their impact on the “aesthetic impression created through the consumer’s visual perception.”

The concept of the “Essential Part” of a design is crucial here.

Comparison of Aesthetic Impressions Centered on the “Essential Part”

In court cases and the examination standards of the Japan Patent Office, the assessment of design similarity focuses not merely on the number of differences but on whether the “Essential Part,” which is the part that most attracts the consumer’s attention, is common. The “Essential Part” is determined based on the following elements:

• The nature, purpose, and usage of the article
• Newly created parts that do not exist in known designs (designs already existing in the world)

For example, if a tool is frequently held in hand, the shape of the handle might be emphasized, whereas for a product with a complex mechanism, the part where the mechanism is exposed might catch the eye. Identifying this “Essential Part” and emphasizing the differences in that part is a key legal strategy in asserting non-infringement.

Case of Amazon Japan Listing Suspension Due to Design Patent Infringement Claim

This article explains a case where Company B claimed design patent infringement and requested the suspension of Company A’s product listing on Amazon Japan.

Design Patent Infringement Claim and Listing Suspension on Amazon Japan

Company B filed a claim with Amazon Japan, alleging that Company A’s product infringed on its design patent.

However, in this case, there were fundamental structural differences between Company B’s registered design and Company A’s product. In the process of determining similarity, the focus is on the “essential parts” that most attract the attention of traders and consumers. If there are significant differences in these “essential parts” that result in a distinct overall aesthetic, then “similarity” under the Japanese Design Law does not apply.

Submission of Non-Infringement Opinion by Experts

To request the lifting of a listing suspension on Amazon Japan, submitting a “Non-Infringement Opinion” by experts such as attorneys or patent attorneys is effective.

Since Amazon Japan’s staff may not be experts in Japanese law, the opinion should be structured with a “clear conclusion” and “visually understandable arguments.” It should specify the ASIN, name, drawings of the accused product, and the registered design number for comparison. If necessary, include images explaining the product’s usage to clarify the comparison.

The opinion conducted a “similarity determination” in the following order:

• Comparison of basic structural features (pointing out commonalities)
• Comparison of specific structural features (pointing out differences)
• Identification of “essential parts” (defining the most important parts)
• Impact of differences on the overall aesthetic (explaining why they are not similar)

Here, specific features were emphasized using images to describe how Company B’s design and Company A’s product provide different visual impressions. It is necessary to construct a logic that the “similar points” claimed by the rights holder are not fundamentally important parts (essential parts) and that the product in question employs entirely different innovations (differences in specific structural features).

Moreover, the involvement of experts is a crucial point. If a seller merely states “we are not infringing” in response to a formal claim from the rights holder, Amazon Japan rarely changes its stance. However, when an opinion drafted under the name of an attorney or other representative is submitted, Amazon Japan must consider legal risks, increasing the likelihood of the listing being reinstated.

In this case, the submission of an opinion drafted by an attorney led Amazon Japan to lift the suspension of Company A’s product listing.

Initial Response and Risk Management When Receiving an Intellectual Property Infringement Notice in Japan

When a notification from Amazon Japan (Amazon.co.jp) regarding a “suspected intellectual property infringement” is received, many businesses tend to panic and make incorrect initial responses. However, a calm and strategic approach is key to minimizing business damage. The main “missteps” that businesses should avoid are as follows:

• Immediate Apology and Acknowledgment of Infringement: Responding with “We apologize, we will immediately withdraw the listing” before conducting a legal review can be used as unfavorable evidence in future litigation.
• Ignoring the Notification: If ignored, Amazon Japan may interpret this as an acknowledgment of infringement, increasing the likelihood of account suspension (closure).

The recommended initial actions should ideally be executed within 24 to 48 hours of receiving the notification.

Particularly, the determination of similarity or dissimilarity in design rights is highly specialized. Even designs that may appear “similar” to a layperson can often be deemed “dissimilar” if there are differences in the legal “essential parts.” Leveraging this “legal expertise” is the only way to influence the giant adjudicator that is Amazon Japan.

Intellectual Property Governance and Proactive IP Strategy in Japan

Businesses are encouraged to incorporate intellectual property disputes on Amazon Japan (Amazon.co.jp) not merely as “incidents” but as part of their “risk management” and “competitive strategy” in management.

The best way to prevent unjust claims from other companies is to register the design of your products early. Having a registered design can serve as strong evidence to Amazon Japan that your company is selling based on legitimate rights.

Additionally, including warranty clauses for intellectual property rights (guaranteeing no infringement and compensating for damages in case of any issues) in contracts with suppliers is an important practical defense measure.

Conversely, if your company develops an innovative design, actively acquiring design rights and registering with Amazon Japan’s Brand Registry allows for the swift removal of counterfeit products from the market. This helps maintain brand superiority without getting caught in price wars.

In today’s e-commerce business, intellectual property rights are not just “defensive legal measures” but can also be considered “offensive tools” for generating sales and profits.

Conclusion: Building Proactive and Defensive Intellectual Property Governance with Experts

When conducting business on a massive platform like Amazon Japan (Amazon.co.jp), allegations of intellectual property infringement have become an unavoidable management risk. Particularly with design rights, due to their nature of “aesthetic appeal through visual perception,” subjective interpretations by rights holders often precede objective assessments, leading to unjust suspension of listings.

What is required of businesses is a calm initial response upon receiving an infringement notice and the construction of legal arguments that fully utilize expert knowledge. Precise rebuttals supported by expert opinions serve as an effective countermeasure against Amazon’s automated review processes.

Furthermore, establishing “intellectual property governance” that places such risks at the core of management, while promoting preventive investigations and the securing of one’s own rights, creates a competitive advantage. Strategically leveraging intellectual property rights as “intangible assets” and advancing business with legal legitimacy is essential for the future of e-commerce businesses.

For more detailed information on trademark infringement claims on Amazon Japan, please refer to the following article.

Guidance on Measures by Our Firm

Monolith Law Office is a legal practice with extensive experience in both IT, particularly the Internet, and law. Proper management of intellectual property, such as trademarks that protect brands and patents that safeguard unique technologies, is directly linked to a company’s competitiveness. Our firm offers solutions for intellectual property strategies from a multifaceted perspective. Detailed information is provided in the article below.