Sup. Ct., 524, 525) Mr. Justice Holmes in delivering the opinion of the Court said:

Election is simply what its name imports; a choice, shown by an overt act, between two inconsistent rights, either of which may be asserted at the will of the chooser alone.

So many applications have been made of the rule, thus so clearly stated, that it is not necessary to refer to more of them than appear in the opinion of that case. It is settled that when a choice of inconsistent rights is once made by a person having the right of election and also knowledge or means of knowledge of the essential facts, he is concluded by his action. Here the choice made was deliberate and is unmistakable; it was the secret use for profit and was persisted in for years. If the right to secure protection of the patent laws can be effectively repudiated, it certainly has been here.

This conclusion is reinforced by other considerations of a kindred character which lead to a like result. When the application for a patent was made we think the invention had in legal effect been abandoned. This is plainly related to the question whether there was an election, equivalent to an abandonment, and is of course a question individual to each case. True, as we have seen, it is contended that the efforts made here to preserve the secret were not reconcilable with an intent to abandon the invention. This is based on the theory that in the absence of intervening rights of other inventors a perfected invention may in point of time be indefinitely used in secret and for profit and also in entire consistency with the right to secure a patent on the invention; in a word, that persistence in such secret use, no matter for what length of time, will not justify an inference of abandonment of the invention. The abandonment contemplated by the patent laws naturally has reference to the advantages and protection alike which are obtainable under those laws. Abandonment in this sense must have been intended to signify a relinquishment of patent privileges. (Kendall v. Winsor, 62 U. S., [21 How.,] 322.) As Macomber says:

Abandonment must reside in the acts of the inventor by which he has deprived himself of the right to establish or enjoy the monopoly which he might have secured. (Macomber, Fixed Law of Pat., 2d ed., 2; Walk. on Pats. 5th ed., sec. 91, at p. 110.)

Otherwise stated, abandonment of patent privileges is in every sense material to the patent laws tantamount to abandonment of the invention itself; and, of course, proof of such relinquishment or abandonment may be shown by conduct inconsistent with any other purpose. (Rifle & Cartridge Co. v. Whitney Arms Co., 118 U. S., 22; 6 Sup. Ct., 950; Planing Machine Co. v. Keith, 101 U. S., 479.)

What has already been shown in respect of appellant's and its assignor's conduct in connection with the question of election is clearly

pertinent to the question of abandonment and so need not be repeated. Appellant also contends, it is true, that it is necessary to prove abandonment of the invention to the public. There could be no abandonment that would not inure to the benefit of the public, since the public could be the only possible beneficiary of such a relinquishment; this would be equally true if the invention were cast away or destroyed and the circumstances of the act or conduct of the inventor were consistent only with an intent to abandon the invention. This we think fairly accounts for the use of the words "had been abandoned to the public." (Par. 5, sec. 4920.) When the intent then of sections 4886 and 4920, paragraph 5, is kept in mind, they may be as literally interpreted as counsel claim they must be, and yet forbid issue of the patent in suit. The views thus expressed are fortified by the rule that abandonment may take place at any time. (Elizabeth v. Pavement Co., 97 U. S., 126; 24 L. Ed., 1000.) That rule differs and ought to differ from the statutory rule enacted with reference to the public use of an invention or the act of placing it on sale, since abandonment in itself signifies surrender of the right to a patent. This would seem to indicate a strong reason, if not the very reason, for the omission to prescribe a distinct period within which a patent must be applied for after an invention is perfected. Further, the fact that the public may in some such instances lose the advantages of inventions cannot impair the force and effect of the inventor's conduct, for in all instances abandonment in terms prevents the issue of a patent.

There is still another view to be taken of the course pursued by the present inventor and his assignee. Their conduct was inconsistent with the duty of diligence resting upon an inventor desiring to patent his invention.. This duty was in effect defined by the Supreme Court as early as 1829, when, speaking through Mr. Justice Story, it was in substance declared that withholding disclosure of an invention for a long period of time and for purposes only of profit was opposed to the intent and policy of the constitutional provision and the statutes in relation to patents. At that time the patent laws contained no provision respecting abandonment of an invention; this, however, cannot be important since an abandoned invention could never have been intended to be made the subject of a patent. Moreover, this rule of diligence was also declared by Mr. Justice Daniel, speaking for the Supreme Court, in 1858 in respect of a patent which had been issued after the introduction into the patent statutes of a provision in effect the same as the present one concerning abandonment. In Pennock v. Dialogue (2 Pet., 1; 7 L. Ed., 327,) an infringement suit, the invention involved was perfected in 1811 and the patent obtained in 1818; the patent was for an improvement in the art of making water-hose. In this interval the inventors had

permitted one Jenkins, under an agreement as to price, to use the invention and to sell the product so derived. During much of the time Jenkins was in the service of the inventors and had been instructed by them in the art of making the hose. Verdict and judgment were recovered by defendant in the court below. The statute then applicable authorized a patent to be granted upon application of any citizen who should allege that he had invented a new and useful art, machine, etc, "not known or used before the application." The true meaning of these words was the ultimate question for decision. It was held that, since it would have defeated the object of the law to apply to the inventor the words "known or used," the clause meant that the thing invented was "not known or used by the public, before the application." After determining the question of use as stated, and presumably in view of the lapse of some seven years between the time the invention was perfected and the patent issued, Mr. Justice Story, in announcing the opinion of the Court affirming the judgment of the court below, said:

And thus construed, there is much reason for the limitation thus imposed by the act. While one great object was, by holding out a reasonable reward to inventors, and giving them an exclusive right to their inventions for a limited period, to stimulate the efforts of genius; the main object was "to promote the progress of science and useful arts;" and this could be done best, by giving the public at large a right to make, construct, use and vend the thing invented, at as early a period as possible, having a due regard to the rights of the inventor. If an inventor should be permitted to hold back from the knowledge of the public the secrets of his invention; if he should, for a long period of years, retain the monopoly, and make and sell his invention publicly, and thus gather the whole profits of it, relying upon his superior skill and knowledge of the structure; and then, and then only, when the danger of competition should force him to secure the exclusive right, he should be allowed to take out a patent, and thus exclude the public from any further use than what should be derived under it, during his fourteen years; it would materially retard the progress of science and the useful arts, and give a premium to those who should be least prompt to communicate their discoveries.

The rule of diligence thus declared in respect of an inventor who has perfected his invention was affirmed in Kendall v. Winsor, (62 U. S., [21 How.,] 322; 16 L. Ed., 165,) Mr. Justice Daniel saying:

* * The inventor who designedly, and with the view of applying it indefinitely and exclusively for his own profit, withholds his invention from the public, comes not within the policy or objects of the Constitution or acts of Congress. He does not promote, and, if aided in his design, would impede, the progress of science and the useful arts. And with a very bad grace could he appeal for favor or protection to that society which, if he had not injured, he certainly had neither benefited nor intended to benefit.

And again, (329)

*

* He may forfeit his rights as an inventor by a wilful or negligent postponement of his claims.

*

We do not overlook the contentions of counsel in relation to these two decisions. It is said of Pennock v. Dialogue that the statutory change subsequently made declaring specifically the effect of "public use," in place simply of "use," was designed to prevent a "secret use " from invalidating a patent, and so was intended to change the rule of law laid down in that case; it is said moreover that this effect of the change was recognized in Kendall v. Winsor. We do not so understand the subsequent legislation nor the decision in Kendall v. Winsor. The statutory change from "use" to "public use" was simply to state distinctly in the new statute what Mr. Justice Story held the old one to imply. The contention then that the change was in effect to prevent a secret use from invalidating a patent and to overrule Pennock v. Dialogue is opposed not only to the reason there expressed for construing use to mean public use, but also to the ruling made in that case, and again in Kendall v. Winsor long after the statutory change took place, against any method of withholding an invention from the public for purposes of profit and of seeking later, through application for a patent, to extend the period of monopoly. And as respects Kendall v. Winsor, we think counsel are mistaken in supposing that it is not in harmony with Pennock v. Dialogue. This may be readily seen by comparison of the instructions asked by defendants and denied below in the Kendall-Winsor case with the instructions there given by the learned trial judge (62 U. S., 325-327) in connection with the proofs offered. Opposed testimony has been offered at the trial below concerning Winsor's use of the invention prior to his application for a patent and as to the acts of one of his employees who had left his position and, in violation of a pledge of secrecy concerning knowledge he had obtained of the invention, constructed some machines for defendants below in accordance with the invention. The plaintiff below had also offered testimony tending to show that what he had done with respect to making and selling harness was to remedy defects found in his invention and to simplify and otherwise improve it, and further that he hadconstantly intended to take Letters Patent when he should have perfected the machine.

All this testimony was submitted to the jury with the instructions given, as stated, and the verdict and judgment were in favor of the plaintiff below, the patentee. The conclusive effect then of the verdict, as well as the judgment, in that case was that the use made of the invention prior to the application was experimental and made under a constant purpose to apply for a patent when the invention had been perfected; and the opinion of Mr. Justice Daniel discloses entire approval of the reasoning and opinion of Mr. Justice Story in Pennock v. Dialogue. Following the decision in Pennock v.

Dialogue it was held by the Circuit Court for the District of Columbia in Spear v. Belson (Fed. Cas., No. 13,223; 22 Fed. Cas., 903) that

Belson had no right to use his invention privately for his own gain for five years, and then expect and claim a monopoly from the public for fourteen years more.

Spear v. Belson, as also Pennock v. Dialogue and Kendall v. Winsor, were followed in Lovering v. Dutcher, (Fed. Cas., No. 8,553; 15 Fed. Cas., 1001, 1002.) Mr. Walker, in his work on patents, (5th ed., 110,) treats failure to observe the rule of diligence, where the delay is for purposes of private gain, as actual abandonment. Mr. Frost, however, while recognizing doubt where the inventor resorts to a secret use for purposes of profit, thinks that in England a patent may be granted in spite of the secret use, (1 Frost Pat. Law & Pr., 4th ed., 123, 128-131;) but it is to be observed that in Morgan v. Seaward (1 Web. Pat. Cas., 187, 194) Baron Parke said:

If the inventor could sell his invention keeping the secret to himself, and when it was likely to be discovered by another take out a patent, he might have a monopoly for a much longer period than fourteen years.

Further, in Germ Milling Co., Limited, v. Robinson (3 Rep. Pat. Cas., 399, 408) Lord Justice Bowen said:

* * * It has been thought and may be thought by a certain class of persons to be hard law that the patentee must not make a beneficial use to himself of the invention before he takes out his patent, on the other hand it is to be remembered that if a patentee should be allowed to sell his mysterious and secret product first for a substantial period of time, and then to take out a patent for his invention, he would be able to give himself a longer monopoly than the law gives him; he would be able first of all to give himself a monopoly during the time he was selling his product made secretly, and then he would be able to get the years of monopoly which the statutes give him; so that there is no particular reason to think that the law has been unintentionally left in the state in which it is.1

We therefore cannot think that the rule laid down in Pennock v. Dialogue and Kendall v. Winsor was intended to be qualified by the remarks of Mr. Justice Clifford in Bates v. Coe (C. D., 1879, 365; 15 O. G., 337; 98 U. S., 31) or Parks v. Booth, (102 U. S., 96; 26 L. Ed., 54.) We are confirmed in this by the reference made in Bates v. Coe (C. D., 1879, 365; 15 O. G., 337; 98 U. S., 46) to the decision in Pennock v. Dialogue and to the effect of the legislation enacted since, and particularly by the view expressed by the same

1 It should be noted, moreover, that the views pointed out in the foregoing decisions are in accord with expressions of Mr. Justice Bradley in Elizabeth v. Pavement Co., supra, at page 137 of 97 U. S.; 24 L. Ed., 1000, of Mr. Justice Strong in Planing Machine Co. v. Keith, (101 U. S., 479; 25 L. Ed., 939,) of Mr. Justice Matthews in Smith & Griggs Mfg. Co. v. Sprague, (C. D., 1887, 616; 41 O. G., 1037; 123 U. S., 249; 8 Sup. Cit., 122,) and of Mr. Justice Blatchford in his approval of these two decisions in Root v. Third Ave. Railroad, (C. D., 1892, 706; 61 O. G., 1947; 146 U. S., 210; 13 Sup. Ct., 100.)