Authored By: Abhilasha Choudhary
Campus Law Centre, University of Delhi
Full Case Name: Astrazeneca Ab & Anr. vs Intas Pharmaceuticals Ltd.
Citation: (2021) 87 PTC 374 (Del)
Court: In the high court of Delhi at New Delhi
Date of decision: 20th July, 2021
Bench composition: Hon’ble Mr. Justice Rajiv Sahai Endlaw and Hon’ble Mr. Justice Amit Bansal
INTRODUCTION
The decision in AstraZeneca AB & Anr v Intas Pharmaceuticals Ltd1 is a significant ruling on pharmaceutical patent law in India concerning “double patenting” and ever-greening. The dispute arose from AstraZeneca’s attempt to restrain generic manufacturers from producing Dapagliflozin (DAPA), a drug used for treatment of Type-II diabetes. The Delhi High Court examined whether a pharmaceutical compound already covered by an earlier genus patent could subsequently be protected through a separate species patent.
FACTS OF THE CASE
AstraZeneca held two patents relating to Dapagliflozin:
a broad genus patent (IN ‘147); and
a later species patent (IN ‘625) specifically claiming DAPA.
The genus patent was granted on 15 March 2007 and expired on 2 October 2020.
The species patent was granted on 9 July 2009 and remained valid beyond expiry of the genus patent.
In 2020, several generic manufacturers, including Intas Pharmaceuticals, commenced manufacture and sale of generic DAPA.
AstraZeneca instituted infringement proceedings seeking interim injunctions against the defendants.
Single Judges of the Delhi High Court refused interim relief on the ground that the species patent faced a credible validity challenge.
AstraZeneca appealed before the Division Bench.
LEGAL ISSUES
Whether a compound can be “covered” by a broad genus patent without being “disclosed” by it?
Whether the same invention can be protected by two successive patents with different expiry dates?
Whether the species patent met the criteria for a new, valid patent?
When is it appropriate to stop a generic manufacturer from selling a drug before a full trial is completed?
ARGUMENTS PRESENTED
Appellants’ (Astrazeneca Ab & Anr.) arguments
AstraZeneca’s core contention was based on the distinction between a patent “covering” a compound and “disclosing” it.
They argued that the genus patent (IN ‘147) was a Markush structure covering millions of compounds but only covered DAPA structurally.
They claimed that DAPA was invented in 2001, i.e., after the priority date of the genus patent, and was only specifically disclosed and claimed in the species patent (IN ‘625).
They maintained that these were distinct inventions, with the genus patent protecting a broad class and the species patent protecting the specific, most viable compound.
To meet Indian patentability standards, AstraZeneca argued that the species patent represented a genuine advancement.
They asserted that DAPA was not obvious from the genus patent, as the broad Markush formula provided no guidance for choosing that specific molecule.
They argued the species patent involved a new product with technical advancement and economic significance over the broad class in the genus patent.
AstraZeneca emphasized that IN ‘625 was in its 18th year of life and had been granted in over 70 countries, which they claimed created a strong presumption of its validity.
They contended that the defendants’ 2020 challenges were not genuine, having been filed only as a “counterblast” once AstraZeneca initiated infringement suits.
AstraZeneca argued they disclosed the relevant U.S. patent equivalent as a continuation-in-part of the genus patent.
They claimed that any minor omissions were not “material suppression” and should not invalidate the patent.
They argued that denying an injunction would erode their market share and prevent them from recouping massive R&D costs.
They argued their prices were justified given their investment and that they had already licensed the drug to Indian distributors like Sun Pharma to ensure access.
Respondents’ Arguments
The respondents argued that because AstraZeneca sued for infringement of both the genus patent (IN ‘147) and the species patent (IN ‘625), they had effectively admitted that DAPA was fully and particularly described in the first patent.
Relying on the Novartis vs. Union of India (2013)2 precedent, they contended that if a compound is “covered” by a genus patent, it is deemed “known” from it; there can be no “gap” between coverage and disclosure that allows for a second patent on the same invention.
Intas argued that DAPA was obvious to a person skilled in the art from Example 12 of the genus patent, which described a nearly identical compound.
They asserted that the species patent failed to show any technical advancement or enhanced efficacy over the earlier invention, making it an attempt at “ever-greening”.
The respondents alleged that AstraZeneca concealed material facts from the Indian Patent Office, specifically the USPTO’s double-patenting objections and the subsequent terminal disclaimer filed in the US.
They highlighted a massive price difference, noting their generic drug cost ₹13.90–₹17.50 per dose compared to AstraZeneca’s brand at roughly ₹54–₹57, representing a 250%–350% difference.
They argued that affordable access to diabetes medicine was a critical public health necessity during the pandemic, as diabetic patients faced heightened risks.
COURT’S REASONING AND ANALYSIS
The Delhi High Court upheld the refusal of interim injunctions and reaffirmed the principle of “one invention, one patent.”
The Court held that a single inventive concept cannot receive successive patent protection through separate genus and species patents extending monopoly rights beyond the statutory term.
The Court observed that AstraZeneca had failed to establish any substantial technical advancement or enhanced efficacy distinguishing the species patent from the earlier genus patent.
It also noted prima facie non-compliance with disclosure obligations under s 8 of the Patents Act 1970 due to failure to disclose foreign prosecution history.
On the question of balance of convenience, the Court prioritised public access to affordable medicines, particularly during the COVID-19 pandemic, and held that any monetary loss suffered by AstraZeneca could be compensated through damages.
JUDGMENT AND RATIO DECIDENDI
The Delhi High Court dismissed appeals to uphold the denial of interim injunctions against generic manufacturers, ruling that a single compound (Dapagliflozin) cannot be protected by multiple, successive 20-year patents. The court established that subsequent “species” patents must demonstrate a distinct technical advancement over the “genus” patent, and in this case, failing that, the public interest in affordable medicine outweighed the patent enforcement.
CRITICAL ANALYSIS
The judgment in AstraZeneca AB & Anr. v. Intas Pharmaceuticals Ltd. (2021) has profound significance for Indian patent jurisprudence, specifically regarding pharmaceutical innovations and the practice of “ever-greening.”
Reinforcement of “One Invention, One Patent”: The most significant impact of this case is the clear rejection of “double patenting”. The court established that a single invention cannot be protected by two successive patents to extend a monopoly beyond the statutory 20-year term. This prevents companies from layering a specific “species” patent on top of a broad “genus” patent once the latter has expired.
Curtailing “Ever-greening” Strategies: The ruling acts as a major deterrent against “ever-greening”—the practice of obtaining multiple patents for minor modifications of a drug to prolong market exclusivity. By emphasizing that a species patent must demonstrate a distinct technical advancement or enhanced efficacy over the genus patent, the court raised the threshold for incremental innovations to be granted independent protection.
Clarification on “Selection Patents”: While the judgment does not explicitly ban selection patents, it sets a high bar for their validity. A selection patent (one that picks a specific member from a broad previously patented group) can only be sustained if it shows a substantial advantage or avoids a disadvantage present in the genus patent.
Higher “Person in the Know” Standard: The court introduced a stricter standard for testing the “obviousness” of an invention when the same inventor holds both patents. Instead of the traditional “person ordinarily skilled in the art,” the court applied the threshold of a “person in the know”—the inventor themselves—arguing that they are in the best position to see if the second patent is truly a new step or just a delayed disclosure of the first.
Balancing Monopoly with Public Health: The decision is a landmark for the balance between IPR and public interest. By prioritizing affordable access to generic drugs (which were up to 350% cheaper) over an questionable second patent term, the court reaffirmed India’s commitment to public health, particularly in the context of life-saving medications during the COVID-19 pandemic.
Impact on Section 8 Compliance: The ruling underscored the mandatory nature of Section 8 of the Patents Act, which requires patentees to disclose foreign prosecution history. AstraZeneca’s failure to disclose its “terminal disclaimer” in the US (an admission that its species patent was not distinct from its genus patent) was a key factor in making its Indian patent vulnerable to challenge.
CONCLUSION
The most significant takeaway from AstraZeneca AB & Anr. v. Intas Pharmaceuticals Ltd. (2021) is the judicial reinforcement of the “One Invention, One Patent” principle. The Delhi High Court established that a single product or inventive concept cannot be protected by multiple, successive patents (a broad genus patent followed by a specific species patent) to extend a monopoly beyond the statutory 20-year term. While not explicitly banning selection patents, the ruling makes them harder to defend. The court’s consideration of generic drug affordability—especially for chronic diseases like diabetes—has set a benchmark for balancing private intellectual property rights with the public’s right to health. This judgment was heavily referenced in later disputes, such as Roche v. Natco (2025), where the court further refined the “coverage vs. disclosure” dichotomy.
Footnote(S):
AstraZeneca AB & Anr v Intas Pharmaceuticals Ltd (2021) 87 PTC 374 (Del).
Novartis AG v Union of India (2013) 6 SCC 1
