The Limits of Extended Protection for Well-Known Trademarks: A Comparative Analysis of Post-Brexit UK and EU Approaches

The growing economic significance of brand reputation has driven an expansion of trademark protection for well-known marks beyond the traditional principle of specialty. There are some international and regional frameworks advocating for the strengthening of such protection measures, but they offer little help in clearly defining specific boundaries. Therefore, it is necessary for courts to determine their respective interpretations based on specific cases. And there is an increasing conflict between protecting legitimate goodwill and preventing abuse through anti-competitive overreach, which was brought to the fore after Brexit due to different judicial interpretations in the UK and EU. Therefore, this study compares the case law of the UK after Brexit with that of the EU to explore the boundaries of the extension of protection for well-known trademarks. The key case, "Sky Company v. Sky Kick," was analyzed in detail. This indicates that such protection needs to be subject to the constraints of these two factors: a legitimate purpose with a justifiable reason and a clearly defined scope of protection. The flexible post-event regulatory model of the EU was compared with the strict pre-event regulatory model of the UK, which focuses on ensuring certainty and genuine business intentions. Therefore, the re-adjusted stance of the UK is more effective in protecting competition and innovation, as trademark rights should not be used to intentionally hinder competition, but rather to protect genuine business reputation.