Interference
In the law of PATENTS, the presence of two pending applications, or an existing patent and a pending application that encompass an identical invention or discovery.
When interference exists, the PATENT AND TRADEMARK OFFICE conducts an investigation to ascertain the priority of invention between the conflicting applications, or the application and the patent. A patent is customarily granted to the earlier invention.
Additional topics
Law Library - American Law and Legal InformationFree Legal Encyclopedia: Indirect evidence to Internal Revenue Code