The other party does not get the patent claims and may be precluded from practicing the invention because such conduct might infringe the patent claims of the one who prevailed in the interference proceeding. While an interference proceeding may involve more than two parties, this review is confined to a two-party interference. Such a proceeding may be initiated between two pending applications or a pending application and an issued U.S. patent. If two patents are involved, the Patent and Trademark Office would not have jurisdiction over the controversy, and the matter would have to be resolved in the courts. The owner of one patent may, under certain circumstances, file a reissue application which has claims in common with the other party's patent and seek to have an interference declared in the Patent and Trademark Office.
Conception is the creation of the idea.
Reduction to practice involves verification, which generally involves physical testing to confirm the suitability of the invention for the purpose for which it was designed. If there has been no actual reduction to practice, one obtains the benefit of a constructive reduction to practice as of the date of filing a U.S. patent application that discloses and claims the invention. It is not essential that the invention be in commercially acceptable form for there to be a successful reduction to practice. One who can prove that he or she both conceived and reduced to practice the claimed invention before reduction to practice by the other will win the interference. In some instances, the one who conceives the invention first reduces it to practice second.