The Delhi HC in Macleods Pharmaceuticals Ltd v. The Controller of Patents & Anr. answered whether a revocation petition is sustainable if the defence of invalidity has been taken in an infringement suit and whether a revocation petition is sustainable when the patent has expired. SpicyIP Intern Bharathwaj Ramakrishnan explains the Court’s finding in its judgment in Macleods. Bharathwaj is a 3rd year LLB Student at RGSOIPL, IIT Kharagpur, and loves books and IP. His previous posts can be accessed here.
By Bharathwaj Ramakrishnan
In an interesting judgment pronounced on 15.01.2025, the Delhi High Court had to decide on two questions, firstly, whether a revocation petition is sustainable when the person who filed the revocation petition has already taken the defence of invalidity of the patent in a written statement (but not through a counter-claim) in a separate infringement suit? Secondly, whether a revocation petition is sustainable when the patent in question has expired? Attempting to answer these questions takes both the Court and the interested readers deep into the murky waters of procedural aspects of Patent law and answers to these are not that straightforward as they seem. This post will seek to understand the judgement and see how the Court answered these questions.
First, I will give some context to understand the judgement within the larger scheme of things. I will discuss the case and explain how the Court answered the two questions. The post itself will primarily focus on the first question, with some discussion on the second question. I will also discuss the Ayyangar committee report and its relevance and conclude with some thoughts.
Context Comes First
It has to be mentioned at the start that Boehringer Ingelheim Pharma (the respondents) had filed multiple suits against other pharma companies for introducing the generic version of ‘LINAGLIPTIN’, stating that they are infringing their patent (IN 243301) in both the Delhi and the Himachal Pradesh High Court (see here, here, here). There has also been a divergence between the High Courts in the matter of whether to grant an interim injunction or not (see Shivam and Lokesh’s take on the Delhi HC’s ruling, which disagreed with the HP HC). There is also the associated issue of genus-species patents wherein the validity of the species patent (IN 243301) is in question due to the existence of the genus (a specific ground that has been raised by the petitioners in the Himachal suit). Macleods had been at the receiving end of an interim injunction in the Himachal High Court and had filed a revocation petition under Section 64 before the Delhi HC. It was this revocation petition whose maintainability Delhi HC had to decide in this judgement.
Explaining Revocation under Section 64 and defence of invalidity in an infringement suit under Section 107
First, Section 64. As the judgement itself puts it, revocation for our purposes under Section 64 can be either through a separate revocation petition or as part of a counter-claim in an infringement suit. Thus, it is clear that the section allows “any person interested” to file a revocation petition through two routes. Section 64 also contains a list of grounds under which the validity of a patent can be challenged. Now Section 107(1) states that “in any suit for infringement of a patent every ground on which it may be revoked under section 64 shall be available as a ground for defence.”
Answering some questions
As stated earlier, the Court had framed two questions, answers to which would determine the course of this judgement (it has to be noted that the revocation petition was filed first, after which the infringement suit in the Himachal court was filed). The Court treated a “counter-claim” or a standalone revocation petition under Section 64 as distinct from a defence of invalidity under Section 107 taken in response to an infringement suit. The Court premised its reasoning on mainly three grounds:
1) When a revocation under Section 64 is filed through a separate petition or counter-claim, it can only be entertained by the High Court. A defence of invalidity under Section 107, can be entertained by a District Court.
2) Revocation under Section 64 leads to the removal of the patent from the register. In contrast, a finding of a Court of Claim invalidity or patent invalidity under Section 107 does not have the same effect as only an entry has to be made in the supplemental record, and the finding of invalidity is binding only on the parties.
3) While entertaining a revocation petition, a High Court can seek amendments to the suit Patent in question. This is not possible during an infringement claim in which a defence of invalidity under Section 107 is pleaded.
Due to these differences the Court concluded that the scope of a revocation petition is different from a defence of invalidity that has been taken under Section 107 and thus concluding that the revocation petition is maintainable, distinct from infringement/defence proceedings.
The Court noted that the Patents Act provides both a right to file revocation and also the defence of invalidity in an infringement suit, and the Patent Act does not in any way prevent this or force Macleods to choose one or the other.
Regarding the second question on the validity of the revocation petition after the expiry of the patent, the Court concluded that a revocation petition would be relevant as the suit patent has been asserted and damages sought against the Petitioner in the Himachal Pradesh HC. If the patent is to be revoked, then the suit for infringement is liable to be dismissed and damages denied. Hence, the Court concluded that the expiry of the patent term cannot affect the revocation petition as it has a tangible impact on the question of Macleods’s alleged infringement.
Going back to the Ayyangar Committee for guidance
The Ayyangar Committee, it appears, was aware of the confusion and conflicting decisions that might arise due to the multiplicity of proceedings in the context of revocation, either through a separate petition or counter-claim or as part of an invalidity defence in an infringement suit. Thus, it recommended a legal scheme to avoid multiplicity of proceedings.
The committee recommended that the revocation of the patent would be decided by the HC, which has jurisdictional control over the Patent Office, which granted the patent in the first place, and that the mechanism of counterclaim is to be removed from the Patent Act. Thus, when an alleged infringer seeks to revoke the patent being asserted against him, he must go to the jurisdictional HC and file a revocation petition. As to the claim of invalidity in the written statement in the context of infringement suits, a defence also available in many other jurisdictions, the committee recommended that the finding of invalidity during such proceedings be limited to the parties to the suit.
In addition, it provided for the creation of a supplemental record, which then can record such decisions wherein the Court has found the patent or the specific claims in the patent to be invalid. The reason for maintaining a supplemental record was to serve a public notice function wherein a potential purchaser or a licensee of the patent is aware of the adverse finding of the Court with regard to the patent’s validity. (refer committee report from page 99-106)
The Parliament did not accept the Ayyangar committee’s scheme with regards to doing away with counter-claim as the Parliament through Section 64 provides for revocation via counter-claim something which the judgement itself has recognised. However,the committee’s other recommendations regarding the defence of invalidity in the context of infringement suits and supplemental records are provided under Section 107, and Section 151. As the Court in Macleods notes, Section 151(2) provides for the Controller to make note of any decision of invalidity in an infringement suit in the supplemental record in the prescribed manner. This sub-section has to be contrasted with Section 151(1), which provides for the removal of the patent from the register when the High Court revokes the patent under Section 64.
Concluding Thoughts
The Court’s ruling on the first question closely follows the Ayyangar Committee report, even though the Court does not explicitly cite it. As to the second question, since a suit for infringement can be filed after the patent has expired, it also follows that revocation of the same can also be filed after the expiry date since it will have relevance with regards to the infringement suit.
As to the distinction between a patent invalidity claim and a revocation petition, the distinction is an inheritance from UK law as it existed then and finds mention in other statutes around the world (page 103 of committee report). However, it makes one wonder what the effect of a successful patent invalidity claim under Section 107 is other than a note in a supplementary record. Can the same defendant go on and file a revocation petition and get the patent revoked because an entire patent or some of its claims has been deemed invalid by a district court or a High Court in an infringement proceeding? Can someone from another interested party point to the supplementary record and seek revocation? These questions gain relevance as if there is an invalid patent as determined by the Court during an infringement suit, how come the patent can be also valid and enforced against other parties, is it not sound public policy to revoke those patents deemed invalid in an infringement suit? Why maintain a distinction between defence of infringement and revocation?
The Author wishes to thank his classmates and Swaraj for their input on the post.
