Research exemption is a rule that allows scientists and researchers to use or test a patented invention without getting permission from the owner of the patent. It means that if they are studying a particular invention for scientific purposes or experimenting, they don't have to pay or get permission from the person who owns the patent. The rule helps to promote scientific and technological innovation and allows researchers to explore new ideas, test theories, and contribute to human knowledge without financial constraints. It's kinda like borrowing a toy from your friend to study and learn how it works, without having to ask your friend every time you want to play with it. However, it's important to note that research exemption has limitations, and researchers must follow specific guidelines to avoid infringing on the patent owner's rights.