their similarity. For both thoughts the patent statute has not made provision. It does not provide for a patent to all who have invented something, but authorizes one to the first inventor only. Nor, if it be comprehensible that two minds might produce the same invention coincidentally, has the statute provided for a patent to both. It has simply failed to consider such a case. To assert the contrary would be to maintain that utter strangers, working independently of each other, happening to produce an invention simultaneously, would both be entitled to patents therefore. 217

The cases in which a patent has been directly attacked because issued to joint inventors are comparatively few before the upper courts. In nearly all of such cases, however, the attack has been sustained on the ground that the invention had not in fact been joint.

It is, therefore, perfectly sound as a matter of logic, and probably correct as a matter of precedent, to say that there can not be such a thing as a joint invention, if the invention be considered as a single idea. In such case the idea of means which constitutes the invention must, by its very unity of nature, have emanated from one mind only, and must be credited to but that one mind.

But if an invention can be thought of as a composite of two or more distinct, though co-operating ideas, it is possible for

217 The wording of the statute, which, to Mr. Justice Story, gave countenance to the assertion that such things as joint inventions and joint inventors were contemplated by it has since been changed. The act of 1836, § 6, makes a partial change from the plural to the singular. It reads, “Any person or persons, having discovered any new and useful art, . . . not known by others before his or their discovery or invention thereof, and not, at the time of his application for a patent," etc. "But before any inventor shall receive a patent for any such new invention or discovery, he shall deliver a written description," etc. "The applicant shall also make oath or affirmation that he does verily believe that he is the original and first inventor." As the statute now stands, however, it is worded wholly in the singular; all words indicating the possibility of a plurality of inventors of a single invention have been eliminated. If this change means anything at all, it may be said to indicate the impossibility of joint invention.

it to be the joint product of two or more minds. The separate ideas which go to make up the invention may emanate from different minds, and the credit may be apportioned accordingly. To the writer, the idea of invention as a concept, which pervades all the law, seems to preclude the possibility of a composite of ideas. The credit seems, logically, to be due to the master mind who welds the lesser ideas into the single perfect whole which constitutes the real invention-the one comprehensive concept of means by which a particular result is to be accomplished. But while this seems the logical and consistent view, the contrary opinions of the courts must be recognized as effective authority, and it must be said that, at least insofar as an invention consists of two or more separable ideas, it may be the product of joint inventors to whom a patent may properly issue.

Joint producers of these several ideas which enter into the composite whole of the invention, are not entitled to joint credit for the invention in all cases. When the ideas which each has contributed are of comparatively equal importance, it is possible that they may be jointly entitled to credit for the whole. But when the ideas of one contributor are insignificant compared with those of the other, when one has evolved the principle idea and the other has merely added minor ideas in elaboration of the main thought, only the first one, the originator of the fundamental idea, is entitled to the patent. In the case of Agawam Co. v. Jordan,218 the defense to a suit for infringement was that the patent was invalid, the invention thereby having been made by another than the patentee, namely by one Winslow. On the trial it appeared that Goulding, who later became the patentee, had nearly completed his device when Winslow suggested certain parts for it as improvements upon the ones that Goulding was using. This suggestion was adopted by him, and parts were accordingly made by Winslow, according to his idea, and substituted in the working model of Goulding's device. They proved to be useful auxiliary parts, and the patent in question was then taken out

by Goulding for the whole device, including these parts, as his invention. Of the claim that the invention was Winslow's the court said, "Valuable though it was and is, as aiding in the accomplishment of the desired result, it is nevertheless a great error to regard it as the invention described in the subsequent patent, or as such a material part of the same that it confers any right upon the party who made the suggestion to claim to be the inventor, or a joint inventor, of the improvement, or to suppose that the proof of what was done by that party can constitute any defence, as against the owner of the patent, to the charge of infringement."

CHAPTER V

LOSS OF RIGHT TO A PATENT.

An inventor who, so far as the character of his production is concerned, is entitled to a patent, may lose that right under certain conditions. His invention may have been, at the time of its creation, new and useful, not known or used by others and not described in any printed publication, nor previously patented; nevertheless he may have so acted as to have deprived himself of the patent privilege. For one thing, the statute specifically provides that an invention, even though patentable when made, shall not be patented if it has been in public use or on sale in this country for more than two years prior to the filing of an application for a patent, or if it has been patented or described in any printed publication more than two years previous thereto. Again, an invention can not be patented if it is proved to have been abandoned to the public by the inventor. In the event that the invention were dedicated to the public the right to a patent would be lost to an inventor, as in the case of abandonment, although such a contingency is not expressly covered by the statute.

§ I. PUBLIC USE OR SALE

The phrase of the statute, "in public use or on sale in this country for more than two years," has been very definitely interpreted by the Supreme Court in a way that speaks for itself.219 "The statutory clause upon which the second objection (to the validity of the patent) is founded is in the disjunctive. The language is, 'purchase, sale, or prior use' . 'for more than two years prior' to the application for the patent. The phrase, 'for more,' as thus used, is loose and inaccurate, and is to be understood as if the language were

219 Consolidated Fruit Jar Co. v. Wright, 94 U. S. 92.

19220

earlier than two years prior,' etc., or as if 'for' were omitted from the sentence. This omission would produce the same effect." It is therefore settled that the use need not have continued during two years, as the statute might seem to indicate, nor need sales have occurred throughout a period of two years. It is sufficient if the use, or the sale, took place earlier than two years before the application, whether it continued during the two years or not. 221

SINGLE SALE OR USE. The only real question involved in this topic is as to what constitutes public use or sale within the meaning of the statute. In the Consolidated Fruit Jar case just quoted the court said, "The defects specified are also in the singular. It follows that a single instance of sale or of use by the patentee may, under the circumstances, be fatal to the patent; and such is the construction of the clause as given by authoritative adjudication." In this particular case there was in fact more than one instance of sale or use. The patentee had made at least two dozen of the jars covered by the later patent. Two of these he gave away and some others he sold, and the court found it to be a fair inference that the recipients of them put them to the use for which they were intended.222 But in a later case, this authority was followed in holding the right to a patent to be lost because of a single sale

220 The court quoted Pitts v. Hall, 2 Blatch. 235, as follows: "The patentee may forfeit his right to the invention if he constructs it and vends it to others to use, or if he uses it publicly himself in the ordinary way of a public use of a machine at any time prior to two years before he makes his application for a patent. That is, he is not allowed to derive any benefit from the sale or use of his machine, without forfeiting his right, except within two years prior to the time he makes his application." See other authorities therein cited. Pennock v. Dialogue, 2 Peters 1; Swain v. Holyoke Machine Co., 109 Fed. 154.

221 The earlier statutes did not restrict the use or sale, which would destroy the right to a patent, to a time more than two years before the application. Public use or sale within that time, if with the consent of the inventor would preclude him from obtaining a patent. Pennock v.

Dialogue; 2 Peters 1, 19; Bates v. Coe, 98 U. S. 31, 46; Andrews v. Hovey, 124 U. S. 694, 719.

222 Other authorities are cited in the case. Jenner v. Bowen, 139 Fed. 556.