Patent opposition allows third parties to challenge the validity of the patent application and its grant. Under the Indian Patents Act 1970, this opportunity is given to any third party to file an opposition to the grant of any patent. There are specific durations denoted in the act for the same. Section 25 of the Act deals with the Opposition Procedures.
The Pre-grant opposition could be made or filed after the patent application has been published by the registry, but it should be filled before the grant of a patent. Ordinarily, a patent application will be published only after a period of 18 months from the filing date of the application or the date of priority, whichever comes earlier. In writing to the controller, a person may contest the grant of any specific patent that gets published. The controller after considering the evidence and statements submitted by the Patent applicant decides whether to grant the patent or refuse it or require an amendment to the complete specification to his satisfaction.
The post-grant opposition could be made at any specific time after the grant of the patent but before the expiry of 1 year from the actual date of publication of a patent. Anyone can give a notice to the respective controller for a post-grant opposition. The person who gives the notice for the opposition will have to state the true nature of his interest in the matter. The Person interested must be a person who is engaged in or is simply promoting research on the same field as the related invention. It could be an organization that is manufacturing or trading interest in the goods connected to the patented article or is just having a financial interest in the manufacturing of such goods or is also possessing Patents related to the same subject. The Controller will have to constitute an Opposition Board which will have to comprise of 3 members who have conducted the examination of the Patent and submit their reports on the matter to the controller. After hearing explanations from both the parties and upon considering recommendations of the Board, the controller will decide whether the opposition is valid and inform the parties about the same with substantial reasons. If the parties are not satisfied with the decision, they can appeal to the Appellate Board.
The grounds for pre-grant and post-grant oppositions are actually the same. The Act has eleven grounds on which opposition could be made.