Rethinking The Thresholds In Biosimilar Patent Infringement Disputes

Biosimilar infringement disputes in India are still a comparatively new but growing field of pharmaceutical patent law. The Delhi High Court's Order dated 18 July 2025 in E.R. Squibb and Sons LLC & Ors v. Zydus Lifesciences Ltd.¹ (2025) ('Squibb') is a turning point in the developing field. The Court granted an-interim injunction restraining Zydus from manufacturing, clearing or dealing its biosimilar version of the cancer medication Nivolumab until 2026 i.e., until the expiry of the Indian Patent No. 340060. A biosimilar is a biologic drug developed to closely replicate an already approved biologic, called the reference product. It matches the original drug in terms of safety, efficacy, and quality, but is produced by a different manufacturer once the reference product's patent has expired. While not identical, it is highly comparable in clinical performance. In India, their approval is governed by regulatory authorities like the Central Drugs Standard Control