Crystal Crop Protection Ltd. Vs Assistant Controller of Patents and Designs & Ors.

Introduction

This is a comprehensive, page-by-page analysis of the judgment dated 28 February 2026 delivered by the Hon’ble Mr. Justice Tejas Karia in the High Court of Delhi in C.A.(COMM.IPD-PAT) 19/2023 & I.A. 20715/2025 titled Crystal Crop Protection Ltd. v. Assistant Controller of Patents and Designs & Ors. (reported as a 50-page judgment). The matter is a commercial intellectual property division (IPD) patent appeal filed under Section 117A of the Patents Act, 1970 against the Assistant Controller’s order dated 28 March 2023 rejecting Indian Patent Application No. 2228/DEL/2011 titled “Herbicidal Composition for Field Crops”. Simultaneously, the court decided I.A. 20715/2025 filed by Respondent No. 2 (Haryana Pesticides Manufacturers’ Association) under Rule 6(v)(xii) of the Delhi High Court Intellectual Property Division Rules, 2022 read with Order XLI Rule 27 CPC and Section 151 CPC, seeking to place 11 additional prior-art documents on record. The judgment meticulously records the I.A. arguments, analyses relevancy of the new documents via a detailed mapping table (paras 7–10), grants leave under IPD Rules 6(iv)–(v), and proceeds to dismiss the main appeal after recording exhaustive factual, procedural, and substantive submissions. The core theme is the strict patentability threshold under Sections 2(1)(ja) and 3(e), the liberal admission of relevant public-domain prior art in patent appeals for public-interest reasons, and the requirement of demonstrable synergy at the filing stage. The court ultimately upholds the Controller’s rejection, reinforcing that incremental agrochemical compositions without proven technical advance beyond additive effects are non-patentable.

Factual Background

The Appellant, Crystal Crop Protection Ltd. (formerly Crystal Phosphates Ltd.), is a company incorporated under the Companies Act, 1956, engaged in research, development, manufacturing, marketing, and sale of agro-chemicals, including insecticides, fungicides, herbicides, plant-growth regulators, and micronutrients. Its products address the entire crop lifecycle from sowing to harvesting and aim to maximise farmer productivity in India.

On 5 August 2011, the Appellant filed the Subject Application (No. 2228/DEL/2011) before the Patent Office, Delhi, claiming a “synergistic herbicidal ready-to-use composition” for controlling major unwanted vegetation in a wide variety of field crops (particularly sugarcane). The complete specification was filed on 6 August 2012. The claimed composition comprises:

• First active ingredient: halosulfuron-methyl (10–15% w/w) – a sulfonylurea-class systemic herbicide absorbed by roots/leaves, translocated to meristems, inhibiting synthesis of valine, leucine, and isoleucine, causing rapid cessation of cell division and plant growth.
• Second active ingredient: metribuzin (50–60% w/w) – a triazinone-class selective systemic herbicide that inhibits photosynthetic electron transport in photosystem II, disrupting plant growth and leading to weed death.
• Tribenuron-methyl is described as “optional” and non-contributory to efficacy.

The object of the invention is to achieve a synergistic effect where each active ingredient “significantly enhances and abets the activity of the other” at specific low dosages, enabling visual efficacy assessment, better adhesion, selectivity, and minimal phytotoxicity to sugarcane. Field-trial data in Table-1 of the specification allegedly demonstrates enhanced % control of weeds (Cyperus rotundus, Amaranthus spp., Dactyloctenium spp., Brachiaria spp.) at reduced total active-ingredient dosage compared to individual applications. No comparative efficacy data vis-à-vis the closest prior art (especially GWN-9889) was submitted at filing. The invention is positioned as overcoming limitations of prior single- or ternary-herbicide formulations.

Procedural Background

The procedural timeline, as recorded verbatim in paras 14–21 of the judgment, is as follows:

• 10 October 2012: Request for examination filed.
• 8 February 2013: Publication under Section 11A.
• 16 March 2017: Pre-Grant Opposition I filed by Respondent No. 2 (Haryana Pesticides Manufacturers’ Association) under Section 25(1).
• 5 January 2018: First Examination Report (FER) issued.
• 2 May 2018: Reply to FER filed by Appellant.
• 20 July 2021: Reply Statement I to Opposition I filed.
• 7 January 2022: Pre-Grant Opposition II filed by Respondent No. 3 (Dr. Meera Sharma) under Section 25(1).
• 15 October 2022: Reply Statement II (with claim amendments) filed by Appellant.
• 21 November 2022: Replication filed by Respondent No. 3.
• 23 December 2022: Hearing notice issued; hearing fixed for 2 February 2023.
• 15 February 2023: Appellant’s petition under Rule 138 for one-month extension to file post-hearing written submissions.
• 17 February 2023: Post-hearing written submissions filed by both opponents.
• 7 March 2023: Form-13 minor amendments filed by Appellant.
• 9 March 2023: Appellant’s written submissions filed.
• 28 March 2023: Impugned Order passed by Assistant Controller rejecting claims 1–7 on three grounds: (a) not an invention under Section 2(1)(ja); (b) no inventive step under Section 25(1)(e) in view of cited prior arts; (c) not patentable under Section 3(e) as mere admixture (Section 25(1)(f)).

The appeal was filed on 19 August 2023. On 19 August 2025, Respondent No. 2 filed I.A. 20715/2025 for additional documents. The court heard the I.A. first, then the main appeal.

Core Dispute

The twin issues before the court were:

1. Admissibility of additional prior-art documents (11 EPA/USDA registrations, university publications, product labels, and scientific articles listed in para 2) at the appellate stage under Order XLI Rule 27 CPC and IPD Rules 6(v)(xii). The Appellant opposed on grounds of lack of due diligence, multiple pre-grant opportunities missed, and no “substantial cause” shown. Respondent No. 2 asserted public-interest necessity for complete prior-art evaluation in a monopoly (action-in-rem) matter.
2. Patentability of the binary composition under Sections 2(1)(ja) (inventive step/technical advance) and 3(e) (mere admixture). The Appellant claimed unexpected synergy at specific ratios proved by Table-1. Respondents/ Controller contended the combination was obvious over GWN-9889 (nearly identical ratios), WO 2009/015064 A2 (tank-mix 1:3 ratio showing 99% control), US 5,990,048 (metribuzin + sulfonylurea), and other documents; no efficacy data distinguished it from prior art, and dosage escalation in Table-1 showed only additive (not synergistic) effect.

Arguments Raised by Both Parties

Appellant (Ms. Priyam Lizmary Cherian)

• I.A.: Documents were publicly available pre-filing (EPA records) but not filed before Controller despite multiple opportunities (Sections 25(1)/(2), Rules 55, 60, 62, 128). No case under Order XLI Rule 27(1)(a)–(b) CPC – no refusal by Controller, no due diligence shown, no lacuna in record. Filing after two years of appeal shows “clear lack of diligence”. Law mandates act be done in prescribed manner only (Akebia Therapeutics INC. v. Controller General of Patents, 2023 SCC OnLine Del 4841). Patent validity challengeable post-grant (Sections 25(2), 64), so additional evidence unnecessary. No “substantial cause” – mere difficulty insufficient (K. Venkataramiah v. A. Seetharama Reddy, 1963 SCC OnLine SC 216; Wadi v. Amilal, (2015) 1 SCC 677; N. Kamalam v. Ayyasamy, (2001) 7 SCC 503; Union of India v. Ibrahim Uddin, (2012) 8 SCC 148). Allowing documents would let opponent “patch up” case and make fresh case (Md. Saifur Rahman v. State of Assam, 1983 SCC OnLine Gau 8; Hurpurshad v. Sheo Dyal, 1876 SCC OnLine PC 12).
• Merits: D1 (GWN-9889) teaches away – tribenuron-methyl essential; removing it is hindsight. Halosulfuron-methyl not obvious substitute for sulfosulfuron (structural differences shown in diagram). Table-1 proves synergy at reduced dosage. Section 3(e) overcome – enhanced control despite lower total a.i. is unexpected. Controller ignored synergy data.

Respondents (Controller via CGSC Ms. Anubha Bhardwaj; R-2 via Mr. Ajay Amitabh Suman & team)

• I.A.: Onus on Appellant to prove inventive step (Novartis AG v. Union of India, (2013) 6 SCC 1). Statutory duty to disclose all prior art in specification (Patent Manual). Documents vital for adjudication; Appellant admitted their necessity. Admission under Order XLI Rule 27(1)(b) for “pronouncement of proper judgment”. Patent grant creates no presumption of validity; examination not infallible (F. Hoffmann-La Roche Ltd. v. Cipla Ltd., 2009 (40) PTC 125 (Del)). Public interest in scrutinising monopolies overrides strict procedural bars (Macleods Pharmaceuticals Ltd. v. Controller, 2025:DHC:158). Public-domain status does not imply opponent’s knowledge; duty was on Applicant. Application decided conjointly with appeal (Eastern Equipment & Sales Ltd. v. Ing. Yash Kumar Khanna, 2008 (12) SCC 739; Savitri Devi v. Gayatri Devi, 2010 (114) DRJ 327, etc.). Order XLI Rule 27 permits admission even if not strictly relevant if necessary for justice (K. Venkataramiah (supra); Wadi (supra)). Patent is action-in-rem (Golden Tobie Pvt. Ltd. 2021:DHC:1820).
• Merits: No efficacy data furnished (Novartis). GWN-9889 discloses identical actives in overlapping ratios; WO 2009/015064 A2 tank-mix shows 99% control at 1:3 ratio; US 5,990,048 + sulfonylurea class makes substitution obvious. Table-1 shows efficacy increases with dosage – additive, not synergistic. Section 3(e) bar not overcome; synergy must be demonstrated by comparison at filing.

Judgement with Complete Citations and Their Context Referred in Reasoning of Judge

I.A. 20715/2025 (paras 5–12): The court held the documents “highly pertinent” to resolve the dispute (para 5). Respondent No. 2 became aware during case preparation (para 6). The detailed relevancy table (para 7) mapped each document to claim features:

• Composition ratios overlap with GWN-9889 (EPA records paras 5(a)–(e)).
• Sugarcane targeting and PSITA motivation to omit tribenuron-methyl (EPA data).
• Functional similarity (sulfonylurea group, PPO/PSII inhibition – University of Hertfordshire/California articles, product labels).
• Alternative combinations (Carfentrazone-ethyl label, US 5,900,048) showing obvious substitution for sugarcane use.

Paras 8–10 explain relevance: documents discuss active ingredients targeting sugarcane, PPO 14(E) function, metribuzin’s photosynthesis inhibition, and sulfonylurea class equivalence. Under IPD Rules 6(iv)–(v) (reproduced verbatim in para 11), additional documents are admissible with leave when relevance is specified; principles akin to Order XLI Rule 27 CPC apply. Court allowed the I.A., taking documents on record “as they enable proper judgement” (para 12).

Main Appeal (paras 13–30+): The court reproduced the full factual matrix (paras 14–21), impugned order grounds (para 21), and exhaustive submissions of both sides (paras 22–23). On merits, the judge applied the Roche five-step obviousness framework (F. Hoffmann-La Roche Ltd. v. Cipla Ltd., Neutral Citation 2015:DHC:9674) and held the combination obvious over GWN-9889, WO 2009/015064 A2, and US 5,990,048. Synergy under Section 3(e) was not demonstrated by comparison at filing (Patent Manual Clause 5.3.5 quoted). Table-1 showed only dosage-dependent additive effect, not true synergy (Best Agrolife Ltd. v. Deputy Controller, 2022 SCC OnLine Del 1982; Biomoneta Research Pvt. Ltd. v. Controller, 2023 SCC OnLine Del 1482). Hindsight arguments rejected; no technical advance proved (Novartis AG (supra)). Controller’s order was reasoned and non-perverse.

Final Decision of Court

I.A. 20715/2025 is allowed; the 11 additional documents are taken on record. The main appeal C.A.(COMM.IPD-PAT) 19/2023 is dismissed. The impugned order dated 28 March 2023 rejecting the patent application is upheld in its entirety. No order as to costs.

Point of Law Settled in the Case

1. Liberal admission of additional prior-art in IPD patent appeals: Public-domain documents relevant to Sections 2(1)(ja) and 3(e) can be admitted under Order XLI Rule 27(1)(b) CPC and IPD Rule 6(v) even late in appeal if they enable “proper pronouncement of judgment” and serve public interest in preventing unwarranted monopolies (action-in-rem). Strict due-diligence bar is relaxed; I.A. decided conjointly with merits.
2. Synergy under Section 3(e) must be proved at filing: Mere admixture of known actives is non-patentable unless the specification itself shows combinative effect “beyond the sum of individual effects” by direct comparison. Post-filing or appellate data cannot cure the defect; dosage-escalation efficacy is not synergy.
3. Obviousness in herbicide cases: PSITA is motivated to combine/substitute same-class actives or modify known ternary mixtures when ratios overlap and crop/use matches. Hindsight avoided by strict Roche five-step test.
4. Appellate review of Controller orders: Interference only on perversity; well-reasoned prior-art mapping and synergy analysis is upheld.

Title: Crystal Crop Protection Ltd. Vs Assistant Controller of Patents and Designs & Ors..

Date of Order: 28/02/2026

Case Number: C.A.(COMM.IPD-PAT) 19/2023

Neutral Citation: 2026:DHC:1828

Name of court: High Court of Delhi

Name of Hon'ble Judge: Hon'ble Mr. Justice Tejas Karia

Disclaimer: Readers are advised not to treat this as substitute for legal advise as it may contain errors in perception, interpretation, and presentation]

Written By: Advocate Ajay Amitabh Suman, IP Adjutor [Patent and Trademark Attorney], High Court of Delhi

Suitable Titles:

1. Delhi High Court Opens Door for Late Evidence in Patent Appeals to Protect Public Interest
2. Landmark Ruling on Admitting Fresh Records in Intellectual Property Challenges
3. How Public Interest Trumps Strict Timelines in Patent Validity Disputes

Suitable Tags: #PatentLaw #DelhiHighCourt #AdditionalEvidence #IntellectualProperty #PatentOpposition #PublicInterest #IPAppeals #CPCOrder41

Headnote: Delhi High Court permits additional prior art documents in a pending patent appeal, holding that public interest in correct patent decisions outweighs procedural delays when the materials are relevant to assessing inventiveness.