The Doctrine Of Equivalents In India: Judicial Approaches And Evolving Jurisprudence

Written by:Anushree Kushwaha, BA.LL.B , 4^th Year, UPES Dehradun

Abstract

In India's booming technology advancements, intellectual property protection is a top priority. Patents are a critical tool to safeguard innovations, yet it is a big challenge when unauthorised parties make substantial or minor changes to a patented invention to avoid literal infringement. This is where the Doctrine of Equivalents comes in play, a legal concept that enables courts to rule on infringement when a product does not literally read on a patent's claims but protects the inventor's core inventive idea. This paper's core message is about the evolution of the Doctrine of Equivalents in Indian patent law. It explains how Indian courts have developed a smooth, balanced approach to prevent unauthorised parties from getting around patents by making only minor changes. The paper begins by establishing the need for this doctrine in India's fast-growing technological landscape. The core issue is how Indian courts interpret patent claims when alleged infringing products do not fall under the literal claim language but may be equivalent. The Indian judiciary has progressively accepted the Doctrine of Equivalents to prevent circumvention of patent rights by minor, insubstantial alterations that perform the same function, in the same way, to achieve the same result, a standard often summarised as the function-way-result test. While not explicitly codified in the Indian Patents Act, 1970, the application of this doctrine has matured significantly in Indian courts. The recent notable cases include the Delhi High Court’s recognition of technical effect in software patents, Blackberry Limited v. The Assistant Controller[1], the Crystal Crop case’s[2] reinforcement of claim boundaries and explicitly adopted the Triple Identity Test and also SNPC Machines Private Limited & Ors. v. Mr Vishal Choudar[3], prioritisation of the Doctrine of Pith and Marrow over the ‘all elements rule’ and the doctrine coupled with the triple identity test. These decisions reflect a cautious yet progressive approach, balancing innovation protection and indicating a trend towards the nuanced application of DoE in complex technologies. Tests and standards adopted by the Indian Courts are used to determine if something is an infringing equivalent. Indian courts use tests similar to those in other countries. They apply an all-elements test, which means they check if the accused product has all the essential parts of the patented invention or their equivalents. Courts also use purposive construction to interpret a patent's claims, focusing on the inventor's true intent rather than just the literal words. Finally, they use prosecution history estoppel, which prevents the patent holder from arguing that a claim is broader than what they told the patent office during the application process.

Recent court decisions also show that Indian courts are becoming more sophisticated in handling these complex technical cases. They are using specialized knowledge to analyse whether a product is functionally equivalent to a patented invention. The establishment of dedicated intellectual property (IP) divisions in High Courts suggests that the application of these principles, including the Doctrine of Equivalents, is becoming more refined and may even extend to new fields like software patents.

Key Words: Doctrine of Equivalence, Patent Infringement, Purposive construction, All element test, Judicial Interpretation.

[1] BlackBerry Ltd v Controller of Patents and Designs (2024) 100 PTC 72 (Del).

[2] Crystal Crop Protection Ltd v Safex Chemicals India Ltd and Ors 2025 DHC 3382.

[3] SNPC Machines Pvt Ltd and Ors v Vishal Choudary MANU/DE/1825/2024 (Del).

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Volume 2 | Issue 2