SMYTH, Chief Justice.
The Commissioner of Patents refused to allow claims 1 to 5, inclusive, of Henderson’s application, on the ground that he was estopped from asserting them. Claim 1 is representative of the others, and is as follows:
A controller having positive and negative line terminals and terminals for the device to be controlled, an electromagnetic switch for connecting one of *708the line terminals to one of the terminals for said, device, another electromagnetic switch for connecting the same line terminal to the other terminal for said device, a third electromagnetic switch for connecting the first terminal for said device to the other line terminal, and means for energizing said switches so that the first switch may close alone and the other two may he in closed position at the same time.
In April, 1908, one Gilpin filed an application on which a patent issued in August'of the same year. A little over a month afterwards Henderson filed his present application, in which claims 1 to 6 of the Gilpin patent were copied. He requested an interference with the latter which was declared. All the tribunals of the Patent Office decided against him, and this court affirmed the Commissioner’s decision. Henderson v. Gilpin, 39 App. D. C. 428. In February, 1913, the claims of the interference in Henderson’s application were finally rejected in accordance with the practice in the Patent Office.
Henderson waited almost a year and then presented claims similar to those before us. They were rejected on the ground,of res judicata. After much delay he again presented the disallowed claims, rewritten, however, so as to improve their terminology but without changing their substance. They were finally rejected and are now before us on appeal. The examiners in chief held that Flenderson was .estopped by judgment, and the assistant commissioner that he was estopped en pais.
[1,2] With respect to the estoppel by judgment, if there is such an estoppel in this case it must be touching the exact thing in judgment— not what might have been adjudicated—because the claims having been taken from Gilpin’s patent could not be changed, so as to bring into judgment matters outside of them. Henderson, therefore, is bound only by the thing passed upon. ■ It covered means for electrically operating a “motor” in either direction. In the present proceeding the invention relates to a “device” electrically controlled so that it will move backwards and forwards. Now, a motor is a device, but a device may be a motor or something else. When, however, we consider the appealed claims in connection with the specifications, we are convinced that the “device” of the issue is identical with the “motor” of the interference. The subject-matter, then, of the two proceedings is the same; so are the parties, for the commissioner represents Gilpin. In re Dement, 49 App. D. C. 261, 263 Fed. 813, and cases cited. It follows that Henderson is estopped by the judgment. Blackford v. Wilder, 28 App. D. C. 535.
In re Curtiss, 46 App. D. C. 183, relied on in this regard by Henderson, does not conflict with anything we have said. It was asserted in that case that the decision in an interference proceeding between Curtiss and one Janin had disposed of the questions then before the court, but the contention was rejected because the claims in the first case related to a flying machine capable of arising from the surface of the water, while in the case which the court was considering a skimming boat was the subject of the controversy. In other words, the subject-matter of the one case was different from that of the other. Not so here.
*709If we assume, however, that the subject-matter is not the same, that would not save Henderson, because he is undoubtedly estopped en pais.
[3] We have shown the dilatory course pursued by him in the Office. He took every moment of time allowed by law’. While ordinarily this would not have harmed hiiii, it must be held otherwise here because of the interposition of certain equitable principles. Equity has a place in the administration of the patent law (Hisey v. Peters, 6 App. D. C. 68; In re Mower, 15 App. D. C. 144; Scott v. Scott, 18 App. D. C. 420; Computing Scale Co. of America v. Automatic Scale Co., 26 App. D. C. 238), and shields the innocent from the consequences of practices that are unfair.
[4] Henderson had access to the Gilpin papers in the interference. Pie knew whether Gilpin’s disclosure would support a claim such as he, Henderson, is now asserting. If it would, Gilpin would have a right to apply for a reissue to cover it, provided his application was made within the time provided’ by law. Equity required Henderson to make known to Gilpin before the lapse of that time that he had a claim which, if allowed, would dominate Gilpin’s. If he had done so, the latter would have had an opportunity to defend himself; but Plenderson did not do this. Instead he waited until Gilpin was helpless, and then sought to take from him what this court had awarded him in Henderson v. Gilpin, 39 App. D. C. 428.
[5, 6] Not only is Gilpin interested in this phase of the case, but the public is also, and it is the duty of the Commissioner to protect the public as well as the litigants. In re Marconi, 38 App. D. C. 286, 290; Moore v. Chott, 40 App. D. C. 591, 596; In re Drawbaugh, 9 App. D. C. 219, 240. Gilpin under his patent has enjoyed a monopoly of the invention for about 12 years. A reissue would not extend his monopoly beyond 17 years. If, however, we yield to Henderson’s contentions, he would receive a patent which would run 17 years from its date, thus stretching the time of the monopoly to which the public would be subjected at least 12 years more than the law contemplates. Considering, as we must, the rights of Gilpin and the rights of the public, we are clear that Henderson is estopped en pais. Moreover, it is the law that a losing party in an interference is not entitled to claims that would dominate the claims given to his successful rival. In re Marconi, supra. This principle would be violated in the present case if_ Henderson was permitted to prevail, for his claims would dominate Gilpin’s.
The decision of the Commissioner of Patents is right, and it is affirmed.
Affirmed.