Patent infringement is when a person or company uses patented intellectual property without permission from the patent holder. The patent holder can grant permission in the form of a license. There are various types of patent infringement, including direct, indirect, contributory, induced, and literal. The legal definition of patent infringement can vary by jurisdiction. In addition, patents can be territorial, which means the patent infringement may not be applicable in certain countries. Patent attorneys can help you fight for your intellectual property rights.