Blatcheord, C. J.
The plaintiff, as the owner of patent No. 114,711, granted May 9, 1871, to it on the invention of John Riley, brings this bill to have cancelled and annulled a patent, No. 100,354, granted March 1,1870, to one Baumann. The bill avers that on the application -of Riley for his patent his application was put in interference with the patent of Baumann; that priority of invention was decided in favor of Riley by the patent office April' 20, 1871; that the defendant owns the Baumann patent; that the plaintiff commenced suit at law in the Massachusetts district against two corporations for infringing said patent by the use of certain materia] put on their boilers and pipes by the agent of the defendant in this suit; that said suits were defended by the defendant in this suit; that it set up, among other defences therein, that the said invention of Riley was not new by reason of said Bau-mann patent and invention; that the court, on a trial, sustained the Riley patent by its decision, and the defendant is concluded thereby; and that the two patents are conflicting and interfering patents. The bill alleges that Riley was the first inventor.
The answer alleges that Baumann was the first inventor. It does not deny that the suits in Massachusetts were defended by it, or that it set up, among other defences therein, that said invention of Riley was not new by reason of said Baumann patent and invention. It denies that the Baumann ,patent formed any part of the issues on which the Massachusetts suit was tried; and that the defendant is not to be prejudiced by reason of said suit, because it was not a party *815to it, and because no party having any interest in the Bau-mann patent was a party to said suit, and because the defendant had at that time no interest in the Baumann patent. The plaintiff put in evidence in this suit the record in -one of the Massachusetts suits, — that against the Merrimack Manufacturing Company, — under an objection by the defendant that it was incompetent. It appears by the proofs in this suit that the defendant supplied the covering for boilers and pipes used by the defendant in the Massachusetts suit; that the president of the defendant employed the counsel who defended that suit; and that the defendant paid for the services of said counsel. The record in the Massaclrasettes suit shows that that suit was brought on said patent No. 114,711, with other patents; that the answer in that suit sets forth that the tilings claimed in the Biley patent were, before Biley invented them, described in the said patent granted to Bau-mann, and known to and used by said Baumann; and that tho finding of the court was that the defendant had infringed the first and second claims of tho Biley patent. It is plain that The first claim of the Baumann patent interferes with tho three claims of the Biley patent. The relief to be given by the court, under section 4918 of the Bevised Statutes, in the case of interfering patents, is relief to be given on a determination of the question as to which one of the two patents was the first invention of the interfering matters. A reference to section 4904 shows that interference means a dispute on the question of priority of invention. That is the dispute in this suit as between Baumann and Biley. That was the dispute in the Massachusetts suit as between Bau-mann and Biley, the defendant in this suit having defended that suit, and sot up in the answer therein that Biley was not and that Baumann was tho inventor of what is claimed in the Biley patent. The Issues were the same in the two suits. On the foregoing facts it must be held that the record in the Massachusetts suit is proper evidence in this suit, and that the judgment in that suit concludes the defendant on the question of priority of invention as between Baumann and Biley.
*816There must be a decree declaring the Baumann patent invalid, as to its first claim, in the whole of the United States, as respects the defendant and all persons who shall derive title under it, to or in said patent subsequently to the entry of such decree, with costs.