• What is the forum in India to file patent invalidity proceedings?

The patent invalidity proceedings can be filed at the Patent Office in Mumbai, Delhi, Kolkata, and Chennai based on the office that granted the patent. However, if the defendant seeks to challenge the patent’s validity during an infringement action, the action must be transferred to the High Court.

• What are the requirements to establish that a patent claim is invalid?

Both lack of novelty and inventive step requirement (obviousness) can be independent ground for invalidity. Section 64 of the Indian Patents Act outlines circumstances under which a granted patent can be revoked.

1. Novelty Grounds: The claimed invention is anticipated by a single publicly known reference, sale of products, or commercial disclosure before the application is filed. If the claimed invention lacks novelty regarding the earlier disclosed knowledge or prior use, this can invalidate the patent.
2. Obviousness Grounds: Claimed invention is obvious to any person skilled in the art and does not involve any inventive step can be invalidated based on obviousness. Suppose a person skilled in the art, such as an expert appointed by the court for testimony, considers the claimed invention to be evident and easily discoverable as of on the priority date of the claimed invention. In that case, the patent claim can be invalidated on the grounds of obviousness.
3. The subject of the claim of the patent is not an invention: A claimed subject matter that does not fall within the criteria of the patentable subject matter, such as defined by Section 3 of the Indian Patent Act, can be invalidated on those grounds.
4. Patent wrongfully obtained: Applicants of the patent should be the inventors who have worked on the invention. Insufficient disclosure of inventors’ details or disclosure of a person as an inventor who is wrongfully mentioned to be the inventor can form the basis of invalidation of the patent.
5. Insufficient disclosure of the invention: If the complete specification does not sufficiently and fairly describe the invention and the method by which it is to be performed, that is to say, the description of the method or the instructions for the working of the invention as contained in the complete specification are not by themselves sufficient to enable a person possessing average skill in, and average knowledge of, the art to which the invention relates, to work the invention.
6. The claims included in the patent are not fully substantiated by the description provided.
7. Failure to disclose information relating to foreign applications as required under Section 8 of the Indian Patent Act.

• Who can file patent invalidation proceedings in India?

Patent invalidation proceedings can be initiated by any person interested in or by the Central Government or as a counterclaim in a suit for infringement of the patent by the High Court.

• What is the burden of proof required to establish that a patent claim is invalid?

The burden of proof is on the person claiming/alleging that a claim is invalid. The requirement would depend upon the grounds invoked supporting the invalidity claim as detailed in response to question 2.

• Is the decision of the Patent Office in invalidation proceeding appealable, and to which courts?

Applicants can file an appeal under Section 117A before the respective High court within three months of the date of the adverse order. Since the dissolution of the Intellectual Property Appellate Board (ex-forum for appeals) in 2021, the jurisdiction of appeals in IP matters has been transferred to the respective High courts that will enact their respective rules, designating the procedures and formalities to be followed.

• Is it necessary to show the working of a patent after grant? Can it be a ground for revocation?

Under the provisions of section 146, every patentee, or a licensee, is required to furnish the information relating to the working of a patent which is essentially a statement as to the extent to which the patented invention has been worked.

Any person interested or the Government can apply for the Revocation of Patent to the Controller with respect to the patent for which compulsory license is granted. The Patent Revocation should be filed within two years of the grant of the compulsory license.

• Whether during invalidation proceedings can a court only partially invalidate a patent?

A court can partially invalidate a patent. While deciding on a counterclaim filed by a defendant in action for infringement, a court can invalidate specific patent claims and hold that the remaining claims are valid.

• Is it possible to amend patent claims during invalidation proceedings?

Yes, it is possible to amend patent claims during the invalidation proceedings. The procedure for amending granted claims is described in sections 58 and 59 of the Patents Act 1970. Even when a patent has been declared invalid, the judge has the power to allow an amendment of the claim rather than to cancel the claim.

• What is the difference between revocation proceedings and post-grant opposition?

A revocation proceeding may be filed against a patent any time after the grant of the patent. But a post-grant opposition can be only filed after the grant of a patent but before the expiry of one year from the date of publication of the grant of a patent. Key differences between post-grant opposition and revocation proceedings include the narrower scope of inquiry in a post-grant opposition and the limited period in which a post-grant opposition can be filed.

• How do you commence invalidation proceedings?

As a first step, it is important to have a good understanding of the patent and accordingly conduct an invalidity search to identify prior art that will hamper the claims of an invention, rendering them obvious and proving that it is not novel.