Successtive patents. "No patent can issue for an invention actually covered by a for mer patent, especially to the same patentee, although the terms of the claims may differ. The second patent, in such case, although containing a claim broader and more generic in its character than the specific claims con tained in the prior patent, is also void. But where the second patent covers matters de scribed in the prior patent, essentially dis tinct and separable, and distinct from the invention covered thereby, and claims made thereunder, its validity may be sustained." Miller v. Mfg. Co., 151 U. S. 186, 14 Sup. Ct. 310, 38 L. Ed. 121.
An improvement is an addition to or alter ation in some existing means, which increas es its efficiency without destroying its identi ty. It includes two necessary ideas : the idea of a complete and practical operative art or instrument and the idea of some change in such art or instrument not affect ing its essential character but enabling it to produce its appropriate results in a more per fect or economical manner ; Rob. Pat. § 210.
No patent can be granted for the mere im portation of an invention brought from abroad ; 'although it is otherwise in England. The constitution, as we have seen, only au thorizes congress to grant these exclusive privileges to the inventors themselves. The mere fact of an inventor having obtained a patent for a device in a foreign country did • not under the act of March 3, 1897, prevent his obtaining a patent for the same thing here, provided he applies for a patent here within seven months from the date of the foreign patent.
By. the act of March 3, 1903, the period has been extended tO one year (and to four months on design patents). When the for eign patent issues before the United States patent issues, the latter expires at the same time as the former, or, if there be more than one, with the former patent having the short est term ; but in no case will the term exceed seventeen years; Bate Refrigerating Co. v. Sulzberger, 157 U, S. 1, 15 Sup. Ct. 508, 39 L. Ed. 601.
By the act of July 8, 1870, an inventor might lodge a caveat in the patent office by virtue of which he was to a certain extent protected while perfecting his invention. The practice was abolished by the act of June 25, 1910, it having been found ineffec tive.
Of the application for a patent. When the invention is conceived or complete, and the inventor desires to apply for a patent, he causes a specification to be prepared, setting forth in clear and intelligible terms the ex act nature of his invention, describing its different parts and the principle and mode in which they operate, and stating precisely what he claims as new, in contradistinction from those parts and combinations which were previously in use. This is accompanied
by a petition to the commissioner of patents, stating the general nature of his invention and the object of his application. One copy of drawings should bt attached to the specifi cation, where the nature of the case admits of drawings ; and, where the invention is for a composition of matter, specimens of the in gredients and of the composition of matter should be furnished.
If the inventor is shown to be the original and first inventor, a mere prior invention of the same thing in a foreign country, if not patented or described in some printed publi cation, will not affect his right to a patent here.
If the applicant, has, either actually or constructively, abandoned his invention to the public, he can never afterwards recall it and resume his right of ownership.
Abandonment may be by conduct from which an intention to abandon will be in ferred, or by public use or sale. In the for mer class, it may be ,before the application; by the application ; or after application. Abandonment before application may be shown by any conduct from which can be inferred an intention to give the invention to the public ; as, by throwing it aside and not using it ; disclaiming any right in it, or giving it expressly to the public; and by public use of the device for even less than two years, taken in connection with circum stances tending to show that the inventor did not intend to secure a monopoly; Rob. Pat. § 349. It is a question of intention ; Mc Cormick v. Seymour, 2 Blatch. 240, Fed. Cas. No. 8,726 ; and of fact ; Russell & Erwin Mfg. Co. v. Mallory, 10 Blatch. 140, Fed. Cas. No. 12,166.
An applicant, either by express words in his specification, or by a failure to claim all of his invention or by unreasonable delay in applying for a revision, may abandon the whole or a part of his invention ; and after application he can abandon his invention by withdrawing his application.