[Article / Unfair competition] Relationship between “confusion” and “business interests” under Unfair Competition Prevention Act Article 2(1)(i) (横山久芳, Patent, October 2023)
更新日：3 時間前
Article information
Categories: Unfair competition law
Topics: Confusion / Well-known and famous marks
Published on this website: 2026-09-29
[Article / Unfair competition] Relationship between “confusion” and “business interests” under Unfair Competition Prevention Act Article 2(1)(i) (横山久芳, Patent, October 2023)
1. Interpreting “confusion in the broad sense”
Item (i) includes both narrow confusion (mistaken belief in identical source) and broad confusion (mistaken belief in a relationship between sources). Since item (ii) was created, regulation of dilution/free riding without confusion should be left to item (ii), while confusion under item (i) should be assessed concretely and substantively.
Tarnishment should be addressed by flexibly interpreting item (ii)’s fame requirement according to the nature of the case, without unduly relaxing confusion under item (i).
If confusion is interpreted leniently, substantive balancing of interests should occur through the requirements of well-known status and injury to business interests.
2. Confusion before and after purchase
(1) Pre-purchase confusion
In principle, item (i) does not apply if confusion is resolved by purchase.
However, it may apply where transaction costs make switching suppliers practically difficult even after confusion is resolved.
(2) Post-purchase confusion
Confusion among users (potential consumers) affects future choices, so item (i) applies. The same holds where confusion among subsequent acquirers is anticipated. Confusion among passing third parties is excluded.
3. Balancing through the injury-to-business-interests requirement
(1) Disputes over the commercial character of the defendant’s activities
If the opposing party alleges and proves that its activities have little commercial character, injury to business interests may be denied (see the Tohoku Aichi case).
(2) Use of identical indications after an internal split
If each side alleges and proves good-faith use of the same indications for the same businesses as before, substantive injury to each other’s business interests may be denied.
4. Persons entitled to claim under item (i)
Entitlement is limited to the “party responsible for the well-known indication,” interpreted flexibly as follows.
This means a person who independently determines how the business using the indication operates, potentially including persons not themselves manufacturing or selling.
Group companies, franchisors and licensees with sublicensing authority may qualify.
Mere franchisees, non-exclusive licensees and developers uninvolved in business activities are, in principle, not entitled to claim.
Originally posted on LinkedIn: https://www.linkedin.com/feed/update/urn:li:activity:7510496567204831233/
