when patent can be revoked?

A patent can be revoked, or invalidated, by a court or a patent office if it is found to be invalid or not in compliance with legal requirements. Here are some reasons why a patent may be revoked:

1. Lack of novelty or inventiveness: If it is found that the invention is not new or obvious, the patent may be invalidated.
2. Lack of enablement or written description: If the patent specification fails to provide a clear and complete description of how to make or use the invention, the patent may be invalidated.
3. Violation of rules and regulations: If the inventor fails to comply with certain legal requirements, such as paying maintenance fees or disclosing all relevant information during the patent application process, the patent may be invalidated.
4. Incorrect inventorship: If it is found that the inventors listed on the patent are incorrect or incomplete, the patent may be invalidated.
5. Fraud or misrepresentation: If it is found that the inventor intentionally provided false or misleading information during the patent application process, the patent may be invalidated.

In some cases, a patent may also be revoked if it is challenged by a third party in a legal proceeding and found to be invalid.