Infringers of patents in India have several weapons available to them in their arsenal.  None was more intimidating for the patent holder than the ‘trident’. Hitherto patents were attacked whenever and wherever possible by the trident. The trident is a weapon with three prongs and   in the case of the Indian Patent Act, the three prongs for revoking a granted patent were -

  1. A post grant opposition which can be filed in the first year after the grant of the patent is published.
  2. The second prong was filing a petition of the patent under Section 64 of the Patents Act.
  3. The third was a counter claim for revocation which can be claimed when a patent holder files a suit for infringement.

In the Indian context, all three prongs could be used simultaneously by an infringer to attack the patent holder and his patent. This was painfully clear in the case of Enercon India Ltd. Vs. Alloys Wobben where the patent holder was attacked both at the IPAB and the Delhi High Court. Mercifully for the patent holder, on June 2, 2014 the Supreme Court has blunted the trident and this weapon will no longer be available collectively for a defendant in a patent infringement suit.

In the first instance, the court laid down that the three prongs could not be used simultaneously by a defendant. Secondly, the use of one prong precluded and excluded the use of any of the other prongs. Thirdly, if a post grant opposition is filed under Section 25(2), this precludes the opposer from taking any action under Section 64.

The end result is that if an action for infringement of patent is filed and the defendant in such a case moves the IPAB for revocation of the patent then in the suit for infringement the issue of validity of the patent cannot be raised and the judge trying the infringement suit is only required to deliberate on whether the defendant is infringing one or more  claims of the plaintiff’s patent. Such a court will be empowered to deal with on the validity of the patent only if the defendant does not move the IPAB and alternatively files a counter claim for revocation. In the case of a  patent which has been recently granted, it is open for the defendant to file a post grant opposition under Section 25(2). If he resorts to this step then he cannot plead invalidity of the patent under Section 64 in his written statement or before the IPAB.