Patents in India have a life of 20 years from the PCT filing date (in case of national phase or regional phase applications) or from the filing date in India.
Patents can be enforced in India only after grant, but damages may be claimed from the date of publication of the patent application.
Post grant opposition can be filed within 1 year from the date of grant.
A patent infringement suit can be filed by the patentee or its licensee.
Patents in India are enforced by obtaining the following reliefs – (a) permanent injunction; (b) damages; (c) interim injunction; (d) litigation costs; (e) seizure and destruction of infringing goods.
An infringement suit must be filed within 3 years from the first cause of action.
Preparation of filing an infringement suit takes about 4 to 5 weeks.
After filing an infringement suit, interim injunction may be sought for within about 4 months from the date of filing the suit.
An interim injunction in a patent infringement suit is granted in less than 30% of the cases.
A patent litigation up to grant of permanent injunction after a trial may last from 2 years to 10 years.
Interim injunction is normally granted if it is well established that there is a prima facie case in favour of the patentee and irreparable harm will be caused to him if interim injunction is not granted in his favour. It must be
established that the patent is valid and infringed.
Unless it is established that the patentee is using the invention in India, no injunction will be granted.
Sufficient proof of infringement must be provided to the court.
Multiple defendants can be named in a single suit for infringement of patents.
Burden of proof of establishing infringement lies on the patentee. But in case of a process patent, if a substantial likelihood is established that an identical product is being made by the same process by the defendant, the burden of
proof shifts on to the defendant.
Indian courts recognize doctrine of equivalence and infringement can not be avoided by making colourable or trivial changes in the patented product.
During trial, either party may conduct discovery by filing an application in court and may also pray for inspection of the premises of the opposite party with prior permission of the court. The court may also appoint commissioners for
the purpose.
The defendant may challenge the validity of the patent on the grounds of novelty, inventive step, non-patentability, insufficient disclosure in the specification, prior secret use, violation of duty of disclosure under Section 8, that
the patent has been obtained by false suggestion or representation. If the defendant is able to create and establish a reasonable doubt on the validity of the patent on such grounds, the court may vacate the interim injunction, if any
granted earlier.
The defendant may also take the defence of the patent being obtained under defective title, or that the patented invention was being used by him for the purpose of experimentation or research or for imparting education. The concepts of
innocent infringement, parallel import, and Bolar provisions are also recognised in India.
In case there is a pending post grant opposition, chances of obtaining an interim injunction are reduced.
If the defendant admits to importing the infringing product while establishing that he had no knowledge of the process used for making it, infringement cannot be held to have occurred.
If it is shown that patentee suppressed material fact or the representation filed by the patentee was deliberately incorrect, then no injunction will be granted in favour of the patentee, and if injunction has been granted, it will be
vacated.
If it is proved that the patented invention is not commercially worked in India to the fullest extent and is not available to the public at an affordable price, no interim injunction may be granted.
In more than 50% of the cases where revocation suit has been filed, no injunction is normally granted.
It is important to appreciate that there are several pharmaceutical inventions which are not patentable in India and if it can be established that the patent was granted on any invention that falls within any such non- patentable
category, no injunction will be granted, and the patent will be revoked.
