What is an interference proceeding?

When two different inventors file patent applications seeking a patent on the same invention, there is often a dispute over the issue of patent priority (that is, over who is entitled to get the patent). This dispute is resolved by an “interference proceeding,” which is a process of review and decision conducted by the United State’s Patent and Trademark Office’s Board of Patent Appeals and Interferences, and it is similar, in some respects, to a lawsuit.