Copyright Protection for Industrial Designs in Japan: The Intersection of Copyright and Design Law

Japanese Attorney at Law - Bengoshi L.L.

• 7 min read

Industrial designs—the aesthetic appearance of products—are valuable intellectual property assets that can significantly influence consumer choice and brand identity. In Japan, the primary legal framework for protecting these designs is the Design Act (意匠法 - Ishōhō), which grants exclusive rights through a registration system. However, the question frequently arises as to whether, and under what circumstances, Japanese copyright law (著作権法 - Chosakken-hō) can also extend its protection to such "applied art" (応用美術 - ōyō bijutsu), especially for designs that possess notable aesthetic features beyond mere functionality.

Historically, Japanese courts have adopted a relatively restrictive stance on granting copyright protection to industrial designs. The prevailing judicial interpretation of "art" (bijutsu) within the Copyright Act has primarily focused on "pure art" (junsui bijutsu)—works created solely for aesthetic appreciation, such as paintings and sculptures—as distinct from applied art, where aesthetic elements are incorporated into utilitarian articles.

This cautious approach has largely been driven by the need to maintain a clear demarcation between the scope of copyright law and the specific regime of the Design Act. The Design Act provides a tailored system for protecting the ornamental aspects of industrial products, requiring novelty and registration, and granting protection for a fixed term (currently 25 years from the filing date). Courts have been wary of allowing copyright—with its automatic protection (no registration needed) and much longer duration (typically life of the author plus 50 years, or 50 years for corporate works)—to broadly cover subject matter seen as the natural domain of design law, as this could undermine the Design Act's specific requirements and balanced term of protection.

Despite this general reluctance, Japanese copyright law and jurisprudence have recognized certain pathways through which applied art might achieve copyright protection:

  1. Artistic Craftsmanship (美術工芸品 - bijutsu kōgeihin):
    Article 2, Paragraph 2 of the Copyright Act explicitly includes "works of artistic craftsmanship" as a category of artistic works. This typically encompasses items that, while potentially possessing utility, are primarily valued for their high artistic quality, often involving skilled handiwork and produced as unique pieces or in limited editions. Examples include artisanal ceramics, lacquerware, and traditional crafts where aesthetic considerations are paramount.
  2. Works "Comparable to Pure Art":
    Beyond items strictly classifiable as artistic craftsmanship, courts have acknowledged that other forms of applied art could be protected by copyright if they possess aesthetic qualities that elevate them to a level "comparable to pure art." However, establishing this has proven challenging, with courts historically employing demanding criteria:
    • High Degree of Aesthetic Quality or Artistic Merit (美の高度性基準 - bi no kōdosei kijun): Several decisions have emphasized that for an applied art design to be copyrightable, it must exhibit a "high degree of aesthetic expression" or "high artistry," akin to that found in pure art. This often implies a level of originality and aesthetic achievement that transcends ordinary design. For instance, the Kobe District Court, Himeji Branch, in a judgment on July 9, 1979, concerning Buddhist altar carvings, suggested that copyright protection is reserved for visual representations aiming for such high aesthetic expression. Similarly, the Tokyo High Court, on December 17, 1991, in the Mokume Keshōshi (wood grain decorative paper) case, indicated that even an item primarily intended for practical application could be copyrighted if it possessed such a high degree of artistry—perhaps comparable to a work by a renowned painter—that it would be commonly recognized as possessing the nature of pure art.
    • Conceptual Separability from Utilitarian Function (分離可能性基準 - bunri kanōsei kijun): This principle, more explicitly developed in U.S. copyright law for "useful articles," considers whether the aesthetic features of a design can be identified separately from, and are capable of existing independently of, its utilitarian aspects. If the design is predominantly dictated by function, or if its aesthetic elements are inextricably linked to its utility, then copyright protection is less likely. The Osaka High Court, on February 14, 1990 (in the Nīchea (Nii Chair) case), stated that "art" under copyright law generally refers to pure art, and applied art can only be protected if it qualifies as "artistic craftsmanship"—defined as something that, apart from its utility and functional aspects, can be appreciated as a complete artistic work in its own right. The Tokyo District Court, in a decision on April 20, 1981 (the Tīshatsu (T-shirt) case), suggested that applied art might be protected if it was created primarily in pursuit of aesthetic expression, without substantial constraints from its practical purpose, and could objectively be equated with pure art such as paintings or sculptures. Conversely, designs for items like decorative window grilles or ornamental streetlights have been denied copyright protection where their aesthetic expression was found to be significantly constrained by practical purposes or did not rise to a level of independent aesthetic appreciation.

Historically, the cumulative effect of these criteria has meant that copyright protection for mass-produced industrial designs in Japan has been the exception rather than the rule.

A Potential Shift: The "Unity of Art" Theory and the TRIPP TRAPP Case

A significant development in this area came with the Intellectual Property High Court (IPHC) decision of April 14, 2015, in the case concerning the iconic TRIPP TRAPP high chair design, often referred to as the TRIPP TRAPP case. This judgment appeared to signal a potential shift in judicial thinking, influenced by the "unity of art" theory (bi no ittaisei no riron).

The "unity of art" theory, which has found favor in some European legal systems, posits that there should not be inherently different or heightened standards of copyrightability for applied art compared to pure art. It argues that the standard criteria for copyright—namely, a creative expression of the author's individuality—should apply across the board. Proponents suggest that drawing a rigid line between "pure" and "applied" art is often artificial and that the existence of a separate design law system should not preclude copyright protection if a work otherwise meets the threshold for copyrightability. Concerns about over-protection for designs of lower creativity, they argue, can be addressed by appropriately limiting the scope of protection rather than denying copyrightability altogether.

In the TRIPP TRAPP decision, the IPHC explicitly stated that "there is no reasonable basis to apply stricter standards for copyrightability to applied art merely because it might also be protectable under design law." The court suggested that imposing such stricter standards could unfairly deny copyright protection to designs that would otherwise satisfy the general requirement for expressing the creator's individuality. Consequently, the IPHC found the TRIPP TRAPP chair design to be an artistic work protectable by copyright, applying standard criteria for creativity (originality and the expression of the designer's personality).

However, the court also introduced an important caveat regarding the scope of protection for such applied art. It acknowledged that because applied art must, by definition, also serve a practical or industrial purpose, the latitude for expressing the creator's unique individuality is often more constrained than in works of pure art. As a result, the court indicated that even if an industrial design is deemed copyrightable, the scope of its copyright protection (i.e., what would be considered an infringing copy) might be relatively narrow. Indeed, while the TRIPP TRAPP chair itself was found to be a copyrightable work, the defendant's chair, which had similarities, was ultimately found not to infringe, likely reflecting this principle of a narrower scope of protection.

The TRIPP TRAPP decision was widely seen as a significant development, potentially opening the door for broader copyright protection of well-designed industrial products in Japan. Nevertheless, its full impact and the consistency with which its reasoning will be adopted by other courts, especially for designs that are perhaps less iconic or possess a lesser degree of distinctiveness, remain subjects of ongoing observation. It did not entirely overturn decades of more restrictive case law, and the inherent tension with the Design Act's role continues to inform judicial approaches.

Interaction with Design Law (Ishōhō)

Japan's Design Act provides the primary and most direct route for protecting the aesthetic appearance of industrial products. Key features of design protection include:

  • Subject Matter: Protects the shape, pattern, color, or a combination thereof, of an article, which produces an aesthetic impression on the sense of sight.
  • Registration Requirement: Protection is contingent upon registration with the Japan Patent Office (JPO).
  • Novelty and Creativity: The design must be novel and possess a degree of creativity (though the standard differs from copyright's creativity).
  • Term of Protection: The duration of a design right is 25 years from the date of filing the application (this was extended from 20 years from the date of registration by a recent amendment).

Given the more straightforward path and specific focus of the Design Act, it remains the principal tool for protecting industrial designs in Japan. Copyright protection for applied art is generally sought as a supplementary or alternative form of protection, attractive due to its automatic nature (no registration) and longer duration. However, as discussed, meeting the threshold for copyrightability for industrial designs is considerably more challenging.

In theory, it is possible for a product design to be protected concurrently under both the Design Act (if registered) and the Copyright Act (if it meets the heightened criteria for an artistic work, particularly considering the TRIPP TRAPP approach).

U.S. copyright law addresses the protection of designs incorporated into "useful articles" (defined as articles having an intrinsic utilitarian function that is not merely to portray the appearance of the article or to convey information). The U.S. employs a "conceptual separability" test, as clarified by the Supreme Court in Mazer v. Stein (347 U.S. 201 (1954)) and more recently in Star Athletica, L.L.C. v. Varsity Brands, Inc. (580 U.S. ___ (2017)).

Under this test, pictorial, graphic, or sculptural features of a useful article's design are eligible for copyright protection if those features:

  1. Can be perceived as a two- or three-dimensional work of art separate from the useful article itself; and
  2. Would qualify as a protectable pictorial, graphic, or sculptural work if imagined separately from the useful article into which they are incorporated (i.e., they would be copyrightable on their own or if fixed in some other tangible medium).

While both Japanese and U.S. law grapple with distinguishing protectable aesthetic expression from unprotectable utilitarian function in product designs, their doctrinal pathways and specific tests differ. The U.S. explicitly focuses on the "conceptual separability" of the aesthetic features. Japan has historically relied on a combination of "high artistic merit" and arguments related to functional constraint, with the TRIPP TRAPP case potentially steering towards a "unity of art" approach that, while affirming copyrightability more readily for artistically distinct designs, may simultaneously imply a narrower scope of protection against similar but not identical designs.

Conclusion

While Japan's Design Act is the primary and most reliable means of protecting the aesthetic appearance of industrial products, copyright law can offer an avenue of protection for "applied art" in certain circumstances. Traditionally, this has been limited to works of exceptional artistic merit comparable to pure art or items of artistic craftsmanship. The TRIPP TRAPP decision has introduced a potentially more liberal standard for copyrightability based on the "unity of art" theory, suggesting that the standard creativity threshold might apply. However, it also indicated that the scope of such copyright protection for functional items might be relatively narrow.

Businesses seeking to protect innovative product designs in Japan should continue to prioritize registration under the Design Act. Nevertheless, for designs possessing significant and conceptually separable artistic character, the possibility of concurrent copyright protection should also be considered, keeping in mind the evolving nature of Japanese case law in this complex intersection of intellectual property rights.