## Facts

- A trademark owner (X) held an earlier registration for the French word mark “L’AIR DU TEMPS” for perfumes and used that mark and its Japanese transliteration 「レール・デュ・タン」 on perfume products in Japan.
- A later registrant (Y) obtained registration of the katakana mark 「レールデュタン」 for goods including cosmetic utensils, ornaments, hair ornaments, bags, and pouches.
- X sought invalidation of Y’s registration (as to certain designated goods), arguing violation of provisions barring (i) registration of a mark similar to a prior registered mark and (ii) registration of a mark likely to cause confusion with another’s business.
- The Japan Patent Office rejected invalidation, finding the marks not similar and finding no likelihood of confusion because X’s mark was not broadly well-known in Japan.
- The Tokyo High Court dismissed X’s action to annul the administrative decision, accepting that X’s mark was well-known in the high-end perfume segment but concluding there was no confusion.
- The Supreme Court accepted review and addressed the meaning of “likelihood of confusion” and the proper method for evaluating it.

## Issues

1. Whether “likelihood of confusion” under Trademark Act art. 4(1)(xv) includes confusion as to affiliation or business relationship (e.g., group company or licensing relationship), not only direct source confusion.
2. What factors must be considered, and from whose viewpoint, in deciding whether a later mark is likely to cause confusion under art. 4(1)(xv), including where the earlier mark is famous within a consumer segment rather than among the general public.
3. Whether use of 「レールデュタン」 on cosmetic utensils, ornaments, and related goods was likely to cause such confusion with “L’AIR DU TEMPS/レール・デュ・タン” used for perfume.

## Decision

- The Supreme Court reversed the Tokyo High Court and annulled the Japan Patent Office’s trial decision.
- The Court held that art. 4(1)(xv) covers “broad” confusion: confusion that the goods come from an entity in a close business relationship (e.g., parent/subsidiary, affiliated company, or brand group) with the owner of the earlier well-known indication.
- The Court adopted a comprehensive, multi-factor test for confusion evaluated from the standpoint of ordinary care exercised by traders and consumers of the designated goods.
- Applying that test, the Court found a likelihood of broad confusion because the marks were the same or highly similar in pronunciation and appearance, X’s mark was well-known and distinctive in the relevant market, and the goods were closely related with overlapping consumers.

## Legal Principles

- “Likelihood of confusion” under Trademark Act art. 4(1)(xv) includes both direct source confusion and confusion as to sponsorship, affiliation, or other close business relationship.
- Confusion is determined by an overall assessment considering: (i) degree of similarity between the marks, (ii) fame and distinctiveness of the earlier indication, (iii) relatedness of the respective goods/services in nature, use, or purpose, (iv) overlap of traders and consumers, and (v) other market conditions, judged by the ordinary care of relevant traders and consumers.
- A mark may be protected under art. 4(1)(xv) even if its fame is concentrated in a particular consumer segment, where related goods and overlapping demand make confusion likely.

## Conclusion

The Supreme Court invalidated a later katakana mark used on accessories and cosmetic-related goods because it was likely to cause broad affiliation confusion with a well-known perfume mark, and it set a multi-factor, ordinary-care framework for assessing confusion under Trademark Act art. 4(1)(xv).


X v. Japan Patent Office, 54 Minshu 1848 (Sup. Ct. July 11, 2000)