virtue of his inventive act, not merely the ownership of his invention, but an inchoate right to the monopoly which is to become vested upon his application for and receipt of letterspatent. This ownership of the invention, and inchoate right to the monopoly, together with the right to perfect his title to the monopoly by obtaining letters-patent, is made assignable by law equally with the patented invention; and an assignment covering these rights and properly recorded secures to the assignee both the invention and monopoly immediately on the issue of the patent. To authorize an issue of the patent directly to the assignee, however, the instrument of assignment must contain a written request to the Commissioner of Patents that the letters-patent may be granted to the assignee, or to the assignee and the inventor jointly if the conveyance operates upon an undivided interest, and must be filed for record in the Patent Office before the date fixed for the payment of the final fee. Such a convey

invention before patent is valid, see Cammeyer v. Newton (1876), 94 U. S. 225; 11 O. G. 287; Hammond v. Mason & Hamlin Organ Co. (1875), 92 U. S. 724; Continental Windmill Co. v. Empire Windmill Co. (1871), 8 Blatch. 295; 4 Fisher, 428; Appleton v. Bacon (1862), 2 Black, 699; Rathbone v. Orr (1850), 5 McLean, 131; Herbert v. Adams (1825), 4 Mason, 15; 1 Robb, 505.

That the right to an invention dates from its discovery, see Wintermute v. Redington (1856), 1 Fisher, 239.

That a mortgage of a future invention will cover it, though the invention be divided and patented in different patents under different names, see Hollins v. Mallard (1854), 10 How. Pr. 540.

That an assignment of "one third of the full and exclusive right to the invention as set forth and described " in a specification about to be filed carries a one-third interest in all the patentable devices described and claimed in such specification and in all patents obtained therefor, see Puetz v. Bransford (1887), 31 Fed. Rep. 458; 39 O. G. 1083.

That alterations in one of such devices and the procuring a separate patent therefor do not take it out of such assignment, see Puetz v. Bransford (1887), 31 Fed. Rep. 458; 39 O. G. 1053.

That an assignee may accept a dif ferent patent in the room of the one agreed to be assigned, and if acting on such acceptance is estopped to claim

See as to this whole subject §§ 409- the other, see Topliff v. Topliff (1887), 122 U. S. 121; 40 O. G. 115.

411 and notes, ante.

2 Sec. 4895, Rev. Stat. That a sale by the inventor before the patent issues secures the invention to the vendee after the patent is granted, see Rathbone v. Orr (1850), 5 McLean, 131.

8 That the patent cannot issue to the assignee unless the assignment contains a request to that effect, and is duly entered for record as prescribed by the rules, see Wright v. Randell (1881), 19 Blatch. 495; 21 O. G. 493; 8 Fed. Rep.

ance transfers to the assignee the legal as well as equitable title to the patented invention; and if by any fraud or accident the letters-patent should be issued in the name of the inventor only, the property in the invention and monopoly will, nevertheless, be vested in the assignee. An instrument purport

591 Hammond v. Pratt (1879), 16 O. solidated Electric Light Co. v. Edison G. 1235. Electric Light Co. (1885), 25 Fed. Rep. 719; 33 O. G. 1597; 23 Blatch. 412.

ing to be an assignment, but not containing this request or not recorded in due season, does not convey the legal title to the patented invention. It may create an equitable title which a court of chancery will enforce against the inventor and against all other parties who, having notice of the assignment, subsequently become interested in the invention; but it cannot prevail over a later assignment which confers a legal title upon a bona fide assignee who has no notice of the former. In the absence of such intervening legal titles, the patent issues to the inventor, as if no equitable title had been previously created, and chancery compels him to receive and hold it as trustee for his equitable assignees, or to convey it to them by a regular assignment.

That an assignment before patent, not requesting the issue to the assignee, is a contract to assign the patent after issue, and creates an equitable title in the assignee, see Hammond v. Pratt (1879), 16 O. G. 1235; Newell v. West (1875), 13 Blatch. 114; 9 O. G. 1110; 2 Bann. & A. 113; 8 O. G. 598; Troy Iron & Nail Co. v. Corning (1852), 14 How. 193.

That the equitable title of an assignee before patent without request, etc., cannot prevail over the legal title of subsequent bona fide purchasers with out notice, see Davis Wagon Wheel Co. v. Davis Wagon Co. (1884), 22 Blatch. 221; 20 Fed. Rep. 699; Wright v. Randell (1881), 19 Blatch. 495; 21 O. G. 493; 8 Fed. Rep. 591.

6 That an equitable prevails over the legal title in a court of equity, and the legal owner is treated as trustee for the equitable owner, see Whiting v. Graves (1878), 3 Bann. & A. 222; 13 O. G. 455. See also § 786 and notes, post.

That the interest in an invention cannot be assigned by parol so as to entitle the assignee to the patent as against the patentee, see Hammond v. Pratt (1879), 16 O. G. 1235.

patent can be specifically enforced in equity, see Hapgood v. Rosenstock (1885), 23 Blatch. 95; 23 Fed. Rep. 86; Hammond v. Pratt (1879), 16 O. G. 1235; Ex parte Edison (1875), 7 O. G. 423.

That a court of equity will not aid an inventor to obtain a patent in violation of his own agreements, see Runstetler v. Atkinson (1883), 23 O. G. 940.

That an assignee before patent, having notice of a prior unrecorded assign. ment, and with such notice procuring the patent to be issued to himself, takes the legal title in trust for the first assignee and may be compelled to convey to him, see Pontiac Knit Boot Co. v. Merino Shoe Co. (1887), 31 Fed. Rep. 286.

That specific performance will not be decreed in favor of one who has repeatedly broken the contract, though the defendant first transgressed it, see Ohio Steel Barb Fence Co. v. Washburn & Moen Mfg. Co. (1886), 26 Fed. Rep. 702; 35 O. G. 1337.

That no specific performance will be decreed where it would avail nothing, or where the petitioner has not acted equitably, see Werden v. Graham (1883), 24 O. G. 101; 107 Ill. 169.

That a contract to assign a future

That though a specific performance

§ 770. Assignment of Extension.

When the law provides for the grant of an extension to the patentee, he may assign his right to the extension in the same manner, even before the original patent has been issued.1 Such an assignment creates an equitable title in the assignce, which becomes operative on the grant of the extension, and thereupon both the invention and monopoly vest in him according to the terms of his conveyance.2 If the assignee is already an owner of the patented invention under the original patent, the effect of such extension is merely to prolong the period of his existing ownership. If his ownership is to commence with the extension, or to be enlarged thereby, and a has been rendered impossible through the fraudulent act of the defendant, the court will not decree it, see Kennedy v. Hazelton (1888), 128 U. S. 667; Kennedy v. Hazelton (1888), 33 Fed. Rep. 293.

That an employer cannot compel his employee to assign a patent to him unless there was an agreement to that effect, see Hapgood v. Hewitt (1886), 119 U. S. 226; 37 O. G. 1247.

That where a workman is hired to invent, and agrees that his inventions shall belong to his employer, the em ployer is their real owner, see Joliet Mfg. Co. v. Dice (1883), 105 Ill. 649.

That a contract to sell the patent privilege is made good by securing a second patent when the first is void, see Stanley v. Whipple (1839), 2 McLean, 35; 2 Robb, 1.

That under a contract to assign sev eral methods the assignee is not bound to accept an assignment of one, though the others are open to the public, see Serviss v. Stockstill (1876), 30 Ohio St. 418.

That an agreement to transfer property on the happening of a certain event gives an immediate right thereto upon the happening of the event, see McBurney v. Goodyear (1853), 11 Cush. 569.

See further §§ 408-414 and notes, unte, and §§ 786, 1228, 1229, and notes, post.

§ 770. That an extension may be assigned before it is granted, see Consolidated Fruit Jar Co. v. Mason (1877), 7 Daly, 64; Ex parte Holmes (1873), 4 O. G. 581; Nicholson Pavement Co. v. Jenkins (1872), 14 Wall. 452; 10. G. 465; 5 Fisher, 491; Railroad Co. v. Trimble (1870), 10 Wall. 367; Clum v. Brewer (1855), 2 Curtis, 506.

That an extension may be contracted for, but not assigned, before it is granted, see Day v. Candee (1853), 3 Fisher, 9.

That an assignment of an extension, before even the original patent has issued, is valid, see Ex parte Holmes (1873), 4 O. G. 581.

2 That an agreement to assign an extension is valid in equity, see Prime v. Brandon Mfg. Co. (1879), 16 Blatch. 453; 4 Bann. & A. 379; Newell v. West (1875), 8 O. G. 598; 2 Bann. & A. 113; 13 Blatch. 114; 9 0. G. 1110; Pitts v. Hall (1854), 3 Blatch. 201.

That an assignment of a future extension becomes operative on the grant of the extension, see Gear v. Grosvenor (1873), 3 O. G. 380; Holmes, 215; 6 Fisher, 314; Railroad Co. v. Trimble (1870), 10 Wall. 367.

That an agreement to sell an extension creates an equitable title, and becomes a legal title when the price is paid, see Hartshorn v. Day (1856), 19 How. 211.

new conveyance after the extension thus becomes necessary to perfect his legal title, chancery will enforce the preceding equitable assignment by compelling the patentee to execute such further transfer as may be required. Though the extension be not granted until after the death of the patentee, his previous assignments bind it in the hands of his executors or administrators, who without the consent of his heirs or devisees, and without any order from the local court of Probate, may procure the extension and complete the title of the assignee.1

§ 771. Contract to Assign Future Inventions not an Assignment. A contract for the transfer of inventions not yet in being is valid as a contract, but is not an assignment. The subjectmatter of an assignment is an existing invention, not only conceived as an idea of means but actually reduced to practice, and thus invested with the inchoate or perfected right to that monopoly which must always pass with the invention in this form of conveyance. An intended or incomplete invention rests merely in purpose and expectation. It does not clothe the proposed inventor with any special privileges or entitle him to any rights in the monopoly which, if his purpose were accomplished, he might be able to secure. The transfer of such future inventions is a mere executory contract to assign them if they happen to be made. It binds the

That an inchoate right to an extension may be sold, and a contract for such sale specifically enforced in equity, see Newell v. West (1875), 8 O. G. 598; 13 Blatch. 114; 9 O. G. 1110; 2 Bann. & A. 113; Aiken v. Dolan (1867), 3 Fisher, 197.

4 That an administrator may fulfil a contract to convey an extension, by procuring the extension and assigning it, no order of the Probate Court and no consent of the heirs being necessary, see Newell v. West (1875), 13 Blatch. 114; 8 O. G. 598; 9 O. G. 1110; 2 Bann. &

A. 113.

See also as to the assignment of an extension, § 412 and notes, ante, and §§ 779, 844, and notes, post.

§ 771. That the right to an invention can be transferred before it is completed and while its value is prospective and contingent, see Marshall v. Peck (1833), 1 Dana, 609; and §§ 368, 409, and notes, ante.

2 That an assignment entitling the assignee to have a patent issued to him must be a formal assignment of a completed invention, not an agreement to assign future inventions, see Runstetler v. Atkinson (1883), 23 O. G. 940.

8 That an instrument purporting to convey inventions not yet in being is a mere executory contract, not an assignment, see Ex parte Edison (1875), 7 O. G. 423.