actual decisions leave it uncertain, or where there are not decisions upon the matter at all, but in no case have I knowingly done so without pointing out the lack of actual authority.

The comparatively small size of the book is not due to any conscious superficiality of treatment nor omission of pertinent subject matter. It purports to cover only the substantive law of patents, their nature, validity, effect and their characteristics. as property. Matters of procedure in securing patents or suing on them, and the difficult subject of the amount of compensation recoverable by suit, would require a volume for themselves and are not included herein. But of the matter which is included, it has been my desire to present every issue which has come before the courts. Of course I have in no degree cited all the cases, but to the extent that I have accomplished my intention, some part of the discussion will be found applicable to every case. I have sought brevity in such a coordination of propositions and so carefully worked out a sequence of topics as would eliminate duplication of discussion. But for this reason some propositions will not be found under customary headings and reference to the index will be consequently more necessary than is usual.

Although the book is as complete in its field and as thorough as I could make it, it is written primarily for others than patent practitioners. They, presumably, being already trained specialists in this subject, have no longer any need for discussion and exposition of principles. The digests, showing particular applications of the various rules, should be their tools. This book is intended more particularly for the use of inventors, business men, engineers, lawyers in general practice and all that class of laymen who from time to time want information concerning their rights in respect to inventions and patents. JOHN BARKER WAITE.

Ann Arbor, Michigan.

1

CHAPTER I

ORIGIN OF PATENT RIGHTS

THE COMMON LAW does not recognize any right of ownership in an invention. If one has conceived a new means of accomplishing a given result his only right to the exclusive use and enjoyment of that new means is by virtue of statutes; he has no such right in the "unwritten law." So long as an inventor can practically keep his idea a secret it remains his property, to be exclusively enjoyed by him, because the law does not compel him to reveal it. Furthermore, if an inventor has revealed his new idea of means to some other person under an express or implied pledge of secrecy, or through a confidential relationship, the law (equity) will enjoin that person under pain of punishment from breaking his pledge of secrecy. If an inventor embodies his new idea in tangible form, that corporeal embodiment itself is his property just as would be any other tangible thing that he might make, or have made, for himself. The mistaken, but not infrequent, assumption that the corporeal embodiment of the new idea is itself the invention, has given rise to occasional statement that the Common Law, because it recognized the maker's ownership of the corporeal chattel, recognized ownership in an invention. The distinction between the "invention," which is an intangible concept, and the wheels, levers, substances and other tangible things by which the idea is given visible form must be kept clearly in mind. Invention is a mental operation, not a physical act, and an invention is an idea, expressed in some form, visible or audible, and not the tangible thing in which may happen to be demonstrated. Of this, more will be said later.

The idea itself, so soon as it becomes known to others, ceases, so far as the unwritten law is concerned, to be the inventor's property. It is at once open to the use and enjoyment 1 O. & W. Thum Co. v. Tloczynski, 114 Mich. 149.

of any one. As one judge expressed it, "So long as the originator of the naked idea keeps it to himself . . . it is his exclusive property, but it ceases to be his own when he permits it to pass from him. Ideas of this sort, in their relation to property may be likened to the interest which a person may obtain in bees and birds, and fish in running streams, which are conspicuous instances of (animals) ferae naturae. If the claimant keeps them on his own premises they become his qualified property, and absolutely his so long as they do not escape. But if he permits them to go he can not follow them.""

The whole matter of ownership of inventions, therefore, depends upon written law; and the statutes of the country are the beginning and the end of an inventor's exclusive right to the use and enjoyment of his invention.

ROYAL GRANTS. The right of sole enjoyment of an invention originated, in England, from grants made by the sovereign to particular inventors. These grants were evidenced by open letters, which were technically called letters patent or merely patents, and by a sort of metonymy the rights themselves thereby evidenced have come to be commonly known as pat

2 Bristol v. E. L. A. Society, 52 Hun. 161, 5 N. Y. S. 131; To the same effect are, Stein v. Morris, Va. (1917), 91 S. E. 177; Wilson v. Rousseau, 4 How. 646, 673; Gayler v. Wilder, 10 How. 477; Morton v. N. Y. Eye Infirmary, 5 Blatch. 116; Dudley v. Mayhew, 3 Comstock (N. Y.) 9; Comstock v. White, 18 How. Prac. (N. Y.) 421.

As a matter of fact, the idea of "possession" has been so fundamental in the English concept of "property" that the Common Law has been loath to recognize property rights in anything that is not capable of exclusive physical possession. But while it never recognized an exclusive right to an invention, it has conceded property rights in some intangible ideas. An interesting discussion of an author's exclusive right to the subject matter of his compositions as distinct from his tangible manuscript, is found in the early case of Millar v. Taylor, 4 Burr, 2303, esp. 2336 ff. "The present claim is founded upon the original right to this work, as being the mental labour of the author; and that the effect and produce of the labour is his. It is a personal incorporeal property, saleable and profitable; it has indicia certa: for though the sentiments and doctrine may be called ideal, yet when the same are communicated to the sight and understanding of every man, by the medium of printing, the work becomes a distinguishable subject of property, and not totally destitute of corporeal properties."