A patent owner may grant a license to another party. The patent owner should register the license for it to be defensible against third parties. However, failure to register the license does not affect the validity of the license. Compulsory licenses may be granted in limited circumstances, including if the owner fails to exploit their patent.
A patent owner may assign their patent interest – or part of the interest – to another person. They must register the assignment for it to be defensible against third parties. However, failure to register does not affect the validity of the assignment.
Patents may be co-owned. Co-owners may exercise their exclusive rights without accounting to the other. Co-owners cannot grant a license or assign their interest without the consent of the other co-owners.