Patent rights can be lost if:
- Fees required to keep the patent in force (maintenance fees) aren’t paid
- It can be proved that the patent doesn’t
- adequately explain how to make and use the invention
- improperly describes the invention or
- contains claims that are inadequate
- One or more earlier patents or other publications (prior-art references) are uncovered which show that the invention wasn’t new or wasn’t different enough to qualify for patent rights
- The patent owner engages in certain defined types of illegal conduct, that is, commits antitrust or other violations connected with the patent, or
- The patent applicant committed “fraud on the Patent and Trademark Office (PTO)” by failing to disclose material information, such as relevant prior-art references, to the PTO during the period when the patent application was pending.
In short, the patent monopoly, while powerful, may be defeated and is limited in scope and time.