Indigenous Energy Storage Technologies Pvt. Ltd. (“IEST”) is an Indian company focused on transforming bio-waste, particularly cattle manure, into economically viable and environmentally sustainable battery components. Its Indian Patent No. 373806 (“IN’806”), titled Cattle Manure Derived Hard Carbon as Electrode Material for Sodium Ion Batteries and Super Capacitors<\/em>, covers a multi-step process: drying the manure, grinding it, treating the ground material with hydrofluoric acid (HF) at a specified molar concentration and temperature, washing with de-ionised water, vacuum-drying, and finally calcinating at high temperatures under a controlled nitrogen or argon environment. The patent was filed on 4 November 2020, granted on 4 August 2021, and covers both the process and the resulting electrode material for sodium-ion batteries and supercapacitors.<\/p>\n A post-grant opposition was filed by Faradion Limited, a UK based company on 3 August 2021 under Sections 25(2)(b), (e) and (g) of the Patents Act, 1970, relying on three prior art references: D1 (WO 2020\/208341, a PCT application on animal-derived hard carbon), D2 (Atkins’ Physical Chemistry<\/em>, 8th edition, used for its water phase diagram), and D3 (US 2002\/0192553, covering electrode formulations for sodium-ion batteries). The Deputy Controller of Patents (“the Controller”) rejected the novelty objection under Section 25(2)(b) but upheld both remaining grounds, revoking IN’806 on 18 October 2024. IEST appealed to the Delhi High Court under Section 117A of the Act.<\/p>\n The court’s primary and decisive finding concerned procedural method. The court noted that the five-step framework for assessing inventive step as articulated in F. Hoffmann-La Roche Ltd. v. Cipla Ltd.<\/em> and affirmed by a subsequent Division Bench in Tapas Chatterjee v. Assistant Controller of Patents and Designs, 2025 SCC OnLine Del 6369<\/em>\u00a0must be followed sequentially. Step 1, identifying the person skilled in the art, is not a formality: it anchors the entire obviousness inquiry, because the question is always what that<\/em> person, equipped with common general knowledge at the priority date, would have found obvious. The Controller skipped this step entirely, and the court held that this omission alone vitiated the revocation order.<\/p>\n The fifth step, which was ruling out a hindsight approach, was also not followed. The court found that the Controller had, in effect, used IN’806 as a reverse roadmap, dissecting the claimed process into individual steps and then locating each step somewhere in the prior art, without asking whether a skilled person, reading the prior art without knowledge of the invention, would have had any reason to combine those elements in the way IN’806 does. The court cited Agriboard International LLC v. Deputy Controller of Patents and Designs, 2022 SCC OnLine Del 940<\/em> for the proposition that simply cataloguing elements of the prior art and concluding obviousness, without structured analysis, is contrary to Section 2(1)(ja) of the Patents Act.<\/p>\n Beyond the structural failure, the court identified specific technical distinctions that the Controller had not properly considered. The absence of a charring step in IN’806 is not a trivial omission: D1 treats charring as essential to lock carbon into an insoluble matrix and improve purity. A skilled person reading D1 would have had no motivation to remove that step. The substitution of HF for HCl is also substantively significant as HF dissolves and removes SiO\u2082 and metallic impurities, a function HCl in D1 does not perform. These differences were raised in IEST’s reply to the opposition but were not genuinely engaged with in the revocation order.<\/p>\n On Section 25(2)(g), the court found that the Controller had conflated sufficiency of disclosure with a requirement to demonstrate superior yield over prior art through comparative experimental data. The correct test is whether the specification enables a person of average skill in the relevant art to work the invention, not whether the patentee has proven quantitative superiority over every cited document<\/strong><\/span>. IEST’s specification included multiple worked examples sufficient to enable practice of the claimed process, and the opponent had conceded that the best mode had been disclosed.<\/p>\n The court called for the original records to verify the Controller’s repeated assertion that IEST had been given and had failed to use an opportunity to furnish experimental yield data. The records did not substantiate that assertion. Given this finding, the court allowed IEST’s application to place additional experimental evidence on record, relying on Union of India v. Ibrahim Uddin and Another, (2012) 8 SCC 148<\/em>, which permits additional evidence where it is crucial for just adjudication.<\/p>\n In view of the observations and the arguments presented by both the parties, the Delhi High Court held that:<\/p>\nIssues Before the Court<\/h2>\n
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IEST’s Arguments<\/strong><\/h2>\n
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Deputy Controller’s Arguments<\/strong><\/h2>\n
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Court’s Analysis<\/h2>\n
The Five-Step Test Is Not Optional<\/strong><\/h3>\n
Controller Failed to Engage with Substantive Differences<\/strong><\/h3>\n
Sufficiency Ground Misapplied<\/strong><\/h3>\n
Record did not support the Controller’s factual finding<\/strong><\/h3>\n
Findings<\/h2>\n
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