By Jigyasa Pareek

In Vishal Choudhary vs SNPC Machines Private Limited & Ors. [FAO(OS) (COMM) 64/2024], the Division Bench of the Delhi High Court dismissed an intra-court appeal challenging the grant of interim injunction in the infringement suit [CS(COMM) 431/2023] concerning four patents held by SNPC, bearing numbers 353483, 359114, 374814 and 385845, relating to mobile brick-making machines.

The dispute presented the Court with the question: whether infringement analysis ought to be confined to a strict element-by-element comparison of the impugned product against the patented claims, or whether Courts may look beyond literal construction of claims to determine whether the alleged infringer has appropriated the essential and substantial elements / pith and marrow of the invention.

Notably, the key distinction between SNPC’s patented technology and the impugned machine was the manner in which mobility was achieved. The Patentee’s machines incorporated an integrated cabin enabling the assembly to be self-propelled and controlled by an operator seated within the machine. The Appellant-Defendant’s machine, on the other hand, required attachment to a tractor or similar vehicle to facilitate mobility. It was therefore SNPC’s case that the Defendant had merely substituted one mode of achieving mobility for another while retaining the essential features of the patented invention i.e. a mechanism for laying bricks continuously in an organised sequence. According to SNPC, notwithstanding the modifications, both systems embodied the same inventive concept of integrating the hopper, roller and die assembly into a mobile brick-laying mechanism capable of producing substantially the same result.

While granting interim relief in favour of SNPC, the Single Judge had emphasized the adoption of the doctrine of purposive construction over pure literal construction. It opined that the doctrine of equivalents cannot be reduced to a purely mechanical, element-by-element exercise. Identifying the “pith and marrow” of the suit patents, the Single Judge concluded that the inventiveness of both the patented technology and the impugned machine was in ensuring continuous brick laying in an organised sequence. It also remarked that the all elements rule cannot be adopted to the exclusion of the pith and marrow test.

At the threshold, the Appellant challenged the territorial jurisdiction of the Delhi High Court, contending that the impugned machine was neither sold nor supplied within Delhi. The Appellant argued that the Respondent had attempted to create jurisdiction through a purported “trap sale”, relying upon a quotation furnished to a Delhi-based individual. It was contended that a mere expression of willingness to sell, or listings on online marketplaces, does not give rise to a cause of action sufficient to invoke jurisdiction.

The Division Bench rejected this argument and observed that in patent infringement suits seeking injunctive relief, an offer to sell, expression of willingness to supply, or quotation furnished to a person situated within the jurisdiction could suffice to sustain an injunction action. The Court drew a distinction between suits seeking injunctions and those involving damages. While claims for damages may require proof of an actual transaction causing injury, suits seeking purely prohibitory relief could be founded upon the preparedness or potentiality of infringing goods entering the market within the jurisdiction.

On merits, the Appellant argued that the Single Judge had fundamentally erred in assessing infringement. It was contended that the impugned product differed fundamentally from SNPC’s machines in terms of design, functionality and method of operation.

According to the Appellant, the all elements rule ought to have governed the inquiry as pith and marrow test is outdated and incompatible with the statutory framework. It was contended that reliance upon pith and marrow risks enlarging the patentee’s monopoly beyond what is disclosed in the claims. The Appellant invoked the doctrine of equivalents through the function-way-result test, contending that SNPC was required to establish that the impugned product performed substantially the same function, in substantially the same way, to achieve substantially the same result. It was argued that the Single Judge had improperly focused on the fact that both machines ultimately produced bricks while overlooking fundamental differences in their design, operation and mode of mobility.

The Division Bench emphasised the narrow scope of appellate scrutiny applicable to interim injunctions. It observed that the order under challenge represented the exercise of judicial discretion by the Single Judge and that interference would be justified only where the view adopted was ex facie arbitrary, perverse, or unreasonable. In the Court’s view, the findings returned by the Single Judge represented a plausible and reasonable assessment of the material placed on record at the interim stage, notwithstanding the fact that the final outcome could differ upon a full trial and appreciation of evidence.

Significantly, the Court refrained from conclusively resolving the doctrinal debate surrounding the appropriate test for patent infringement. Acknowledging that the authorities on the subject were “numerous and diverse”, the Division Bench observed that any definitive pronouncement on the applicability of the pith and marrow doctrine, the all elements rule, or other tests at the interim stage could prejudice the rights of the parties at trial.

Nevertheless, the Court proceeded to identify the essential inventive concept underlying the suit patents. In its view, the invention was directed towards mechanising the process of brick manufacture through a mobile assembly that integrated the hopper, roller, dies and chassis into a unified system capable of laying moulded bricks directly onto the ground as it moved. The Court observed that the purpose of the invention was elimination of manual labour and enhancement of efficiency.

The Division Bench accordingly endorsed the Single Judge’s conclusion that the differences highlighted by the Appellant, including the absence of an integrated cabin, steering mechanism, steered front wheels and motor-driven movement, were ultimately variations concerning the manner in which mobility was achieved. The Court held that adopting an alternative means of achieving mobility, whether by improvement, development, or the use of another method or mode, could still amount to infringement.

In illustrating this principle, the Court observed that if a similar machine were made mobile through the use of bullocks instead of a tractor, such substitution could not, by itself, avoid a finding of infringement. This illustration was employed to demonstrate that modifications in the means employed do not necessarily negate appropriation of the substance of an invention.

The Court held that the impugned judgement was reasoned and represented a possible and reasonable view. It also upheld the findings of the Single Judge on balance of convenience and irreparable injury.

While the Division Bench consciously avoided laying down a definitive standard governing patent infringement, its reasoning nevertheless suggests a willingness, at least at the interlocutory stage, to protect what is perceived to be the “essence” of the patented invention, notwithstanding variations in implementation.