Patent Strategy in the Cosmetics Industry: Implications of a No-Glue Artificial Eyelash Patent Dispute

The IP & Technology Practice Group of Lee & Ko is representing the patentee of a core patent relating to no-glue artificial eyelashes in preliminary injunction proceedings against multiple companies in Korea that manufacture and sell competing products.

In response, the accused companies have initiated multiple actions before the Korean Intellectual Property Office (“KIPO”), including invalidation trials and trials for confirmation of the scope of patent rights. As a result, civil and administrative proceedings are progressing in parallel. Lee & Ko is leading the overall litigation and trial strategy on behalf of the patentee, encompassing preliminary injunction applications, merits litigation, and patent trial proceedings.

The dispute presents intertwined technical and legal issues concerning a new category of cosmetic products—no-glue artificial eyelashes. A central question is whether specific technical features, such as the extent and method of adhesive application and the mechanism by which the product attaches to a user’s natural eyelashes, fall within the scope of the asserted patent claims.

At the preliminary injunction stage, the patentee must establish a prima facie case of infringement and demonstrate the likelihood of irreparable harm through detailed technical analysis. In the parallel patent trial proceedings, the strategic focus is on defending the patent’s validity, particularly the inventive step of the claimed invention over prior art, and articulating a consistent and legally sound interpretation of claim scope.

As Korean cosmetic brands continue to expand globally amid the prominence of “K-beauty,” the industry is characterized by short product life cycles and the rapid emergence of competing and imitative products. In this environment, early-stage patent registration and proactive enforcement are critical to maintaining competitive advantage. This dispute highlights the importance of promptly enforcing registered patent rights while simultaneously clarifying and reinforcing claim scope through coordinated litigation and administrative proceedings. It provides meaningful guidance for companies in the cosmetics sector in developing effective patent strategies and managing IP disputes.