6.4 Challenges to patents
Under Section 13(4) of the Patents Act, 1970, the grant of a patent does not guarantee its validity.96 The underlying principle is that allowing an invalid patent to continue on the register is against the public interest, so every opportunity is provided to remove invalid patents. There are various levels of challenges provided in the Act against a patent application or a granted patent. Such challenges can be made either prior to or after the grant:
- Pre-grant opposition under Section 25(1);
- Post-grant opposition under Section 25(2) before the Patent Office, introduced in 2005;
- revocation under Section 64(1) before the High Court;97 and
- a counterclaim seeking revocation in a suit for infringement under Section 64(1), in which case the infringement suit and the counterclaim are both transferred to the relevant High Court.98
Other challenges to patents or the exercisable rights are compulsory licenses and government use (under Sections 84, 92, 102 and others) and revocation (under Section 66).
There has been significant discontent – especially after the 2002 and 2005 amendments – about the multitude of challenge avenues. These provisions for patent challenges may appear to encourage abuse by patent opponents and result in patent grants being held up or delayed almost indefinitely. These apprehensions have been assuaged to a large extent by judicial precedents, which have streamlined the filing of oppositions and dealt with challenges to orders passed in oppositions. In UCB Farchim v. Cipla Ltd,99 the Delhi High Court confirmed that, once a pre-grant opposition is dismissed and the patent is granted, the order granting the patent cannot be challenged by way of an appeal. The only remedy available is to file a post-grant opposition or a revocation. In Snehlata C Gupte v. Union of India,100 the practice of filing serial oppositions to hold up the grant of a patent was stopped by the Delhi High Court. The court issued a series of directions preventing delays in patent grants. In Aloys Wobben v. Yogesh Mehra,101 the Supreme Court categorically held that one person cannot pursue both a revocation application and a counterclaim seeking revocation. These and other decisions have ensured that duplicity and parallel proceedings are avoided to the extent possible.