The defendants appeal from the usual decree holding valid and infringed all but three of the claims of a reissued patent, issued to the plaintiff’s assignor, Meduna; the original patent issued on M,ay 25, 1943, upon an application filed on August 6, 1942. The patent is for the process of “so conditioning a metal surface that the same is, as a rule, capable of bonding thereto applied spray metal to a higher degree than is normally procurable with hitherto known practices” (p. 2, lines 1-5). It is primarily useful for building up the worn metal parts of a machine. The art had for many years done this by what the patent calls “spray metal,” which means metal sрrayed in molten form upon the surface which it is desired to build up. This process is called “metaliziug,” and it had been known for nearly thirty years before Medulla’s invention; but about fifteen or twenty years ago it was found that, to secure a satisfactory bond between the “spray metal” and the surface, the surface must be roughened so that there would be fine undercut areas in it upon which the sprayed surface could take hold; and of course the surface must itself be clean. The art had developed two ways of producing such a surface; one, by sand-blasting, and the other, by a tool, so adjusted in a lathe as to tear tiny channels: “screw-threаding.” Meduna’s invention was to prepare the surface by first depositing upon it a preliminary layer of metal by means of a process, disclosed in Patent No. 1,327,267, issued to Brewster and Weisehan, on January 6, 1920. This process was practiced by what the art knew as the “Mc-Quay-Norris” machine, which was “more particularly adaрted and intended for use in the filling of cavities which may occur in castings or other metal objects” (p. 1, lines 17-20). The “McOuay-Norris” device was operated by electric power, one terminal of the circuit being connected with the work, and the other being a fusable electrode, which melted at the temperature developed in the circuit, and deposited parts of itself at the places desired upon closing of the circuit by contact with the work. The process was described as follows (p. 2, lines 47-57) : “The electrode is moved from spot to spot in the cavity and the foregoing operation repeated until the surface of the blowhole is covered by a deposit of the metal by the electrode. It will thus be seen that the surface of the blow-hole is covered by a number of small particles of metal of the electrode, all of which particles are welded to the particular portion of the surface of the blow-hole with which the electrode contacted.” After this has been done, “a peen-ing hammer is employed to peen the metal which has been introduced into the blowhole, thus causing the metal to be compacted, and any inequalities of the surface of the metal reduced” (p. 2, lines 63-68). Meduna did not peen the metal, indeed peening would have been entirely unfitted to his purpose, as it would have pressed together the undercut deposits which later serve to catch and hold the “spray metal.” Moreover, his purpose was not to fill up “blow-holes,” or fissures; but, as we have said, to prepare worn surfaces for rebuilding. However, he used the McOuay-Norris machine unchanged, prescribing a voltage of preferably not more than twenty volts— ordinarily between two and nine — and an amperage of between two hundred and three or four hundred. The surface was to be “repetitiously contacted and preferably repetitiously contact stroked with the electrode on successive areas, the stroking action depositing on these areas small amounts of electrode material firmly bonded thereto. Alternatively the electrode may be applied with a stippling action to the metal surface. While these procedures еssentially involve breaking and making contact between the metal surface and the electrode, it is also possible, and sometimes advisable, to move the electrode relative to the base while maintaining resistant heating contact therebetween” (p. 2 lines 72-76; p. 3, lines 1-8).
The only question which we find necessary to decide is as to Meduna’s public use of the patented process more than one year before August 6, 1942. The district judge made findings about this, which are supported by the testimony and which we accept. They appear as findings 8, 9, 10, 11, 12 and 13 on pages 46 and 47 of volume 62 of the Federal Supplement; and we cannot imprоve upon his statement. The kernel of them is the following: “the inventor’s main purpose in his use of the process prior to August 6, 1941, and especially in respect to all jobs for owners not known to him, was commercial, and * * * an experimental purpose in connection with such use was subordinate only.” Upon this finding he concluded as matter of law that, since the use before the critical date — August 6, 1941 — was not primarily for the purposes of experiment, the use was not ex
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cused for that reason. Smith & Griggs Manufacturing Co. v. Sprague,
Section one of the first and second Patent Acts, 1 Stat. 109 and 318, declared that the petition for a patent must state that the subject matter had not been “before known or used.” Section six of the Act of 1836, 5 Stat. 117, changed this by providing in addition that the invention must not at the time of the application for a patent have been “in public use or on sale” with the inventor’s “consent or allowance”; and § 7 of the Act of 1839, 5 Stat. 353, provided that “no patent shall be held to be invalid by reason of such purchase, sale, or use prior to the application for a patent * * * exсept on proof of abandonment of such invention to the public; or that such purchase, sale, or prior use has been for more than two years prior to such application * * Section 4886 of the Revised Statutes made it a condition upon patenta-bility that the invention shall not have been “in public use or on sale for more than two years prior to his application,” and that it shall not have been “proved to have been abandoned.” This is in substance the same as the Act of 1839, and is precisely the same as § 31 of Title 35, U.S.C.A. except that the prior use is now limited to the United States, and to one year before the аpplication. § 1, Chap. 391, 29 Stat. 692; § 1, Chap. 450, 53 Stat. 1212, 35 U.S.C.A. § 31. So far as we can find, the first case which dealt with the effect of prior use by the patentee was Pennock v. Dialogue,
In the lower courts we may begin with the often cited decision in Macbeth-Evans Glass Co. v. General Electric Co., 6 Cir.,
Coming now to our own decisions (the opinions in all of which I wrote), the first was Grasselli Chemical Co. v. National Aniline & Chemical Co., 2 Cir.,
From the foregoing it appears that in Peerless Roll Leaf Co. v. Griffin &
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Sons, supra, 2 Cir.,
It is indeed true that an inventor may continue for more than a year to practice his invention for his private purposes or his own enjoyment and later patent it. But that is, properly considered, not an exception to the doctrine, for he is not then making use of his secret to gain a competitive advantage over others; he does not thereby extend the period of his monopoly. Besides, as we have seen, even that privilege has its limits, for he may conceal it so long that he will lose his right to a patent even though he does not use it at all. With that question we have not however any concern here. .
Judgment reversed; complaint dismissed.
