is not provided for by the general law when an assignment is made, covered by the word "renewal" in such an assignment. In such a case, that word is held to mean "reissue" and not to mean 66 extension." But if, at the time such an assignment is made, the patent statutes do provide for extensions of patents of the class to which the assigned patent belongs, then the word "renewal" is a sufficient word to convey such an extension. An assignment of an invention, without limitation or qualification, will convey, not only the original term, but also any Patent Office extension, of the patent granted for that invention. Whether such an assignment will convey any Congressional extension, is an undecided point. An affirmative decision upon it will not necessarily follow the rule in Hendrie v. Sayles, but it is not improbable that the Supreme Court will take the step required to pass from the one doctrine to the other, whenever the question arises in that tribunal.

3

§ 281. Recording in the Patent Office, within three months after its date, is necessary to the validity of any assignment of a patent right, as against any subsequent purchaser or mortgagee, for a valuable consideration, without notice.' This statutory provision operates to give constructive notice to subsequent purchasers and mortgagees, of the assignments which are duly recorded thereunder; but it does not apply to any assignment executed prior to the granting of letters patent, unless that assignment is one upon which a patent is to be issued to the assignee, and also identifies with certainty the invention conveyed thereby." But where an assignment conveys a patent, and also conveys all improvements that the assignor may thereafter make on the invention claimed therein, the due recording of that assignment operates to give constructive notice not only of the

1 Wilson v. Rousseau, 4 Howard, 646, 1846.

Pitts v. Hall, 3 Blatch. 201, 1854; Goodyear v. Cary, 4 Blatch. 303, 1859; Chase v. Walker, 3 Fisher, 122, 1866.

Hendrie v. Sayles, 98 U. S. 554,

1878.

4 Revised Statutes, Section 4898. 5 Wright . Randel, 8 Fed. Rep. 599, 1881; New York Paper Bag Co. v. Union Paper Bag Co. 32 Fed. Rep. 788, 1887.

2

sale of that patent but also of the sale of those improvements. Nor does the provision apply to any assignment made by a judge or register in bankruptcy under Title LXI. of the Revised Statutes; but such an assignment though unrecorded more than three months after its date and delivery, will prevail against a subsequently executed but previously recorded assignment of the bankrupt or his executor or administrator. Neither does the provision apply to any assignment which conveyed accrued rights of action only. In such a case, the assignee, in order to protect his right, should give the infringer notice of the assignment; so that if the infringer afterward pays the assignor, or pays some subsequent assignee, for that right of action, he will do so at his peril, and will not discharge his liability to the first assignee.. Recording an assignment of a patent, is not necessary to its validity, as between the parties to that assignment;' nor as against an infringer of the patent;" nor as against an innocent purchaser for a valuable consideration without notice, who takes his assignment within three months after the date of the prior unrecorded assignment; nor as against any subsequent purchaser who had actual notice thereof, when purchasing; nor as against any subsequent purchaser who paid no valuable consideration

1 1 Aspinwall Mfg. Co. v. Gill, 32 Fed. Rep. 701, 1887.

Prime v. Mfg. Co. 16 Blatch. 456, 1879.

3 Gear v. Fitch, 3 Bann. & Ard. 573, 1878.

Woodbridge v. Perkins, 3 Day (Connecticut), 364, 1809; Vanbuskirk . Hartford Fire Insurance Co. 14 Connecticut, 144, 1841; Campbell v. Day, 16 Vermont, 558, 1844; Clodfelter v. Cox. 1 Sneed (Tenn.), 330, 1853; Loomis v. Loomis, 26 Vermont, 198, 1854; Murdoch v. Finney, 21 Missouri, 138, 1855; McWilliams . Webb, 32 Iowa, 577, 1871. Holden v. Curtis, 2 New Hampshire, 61, 1819; Case v. Redfield, 4

McLean, 527, 1849; Black v. Stone, 33 Alabama, 327, 1858; Moore v. Bare, 11 Iowa, 198, 1860; Turnbull v. Plow Co. 6 Bissell, 229, 1874.

Brooks v. Byam, 2 Story, 525, 1843; Pitts v. Whitman, 2 Story, 609, 1843; Boyd v. M'Alpin, 3 McLean, 427, 1844; Case v. Redfield, 4 McLean, 526, 1849; McKernan v. Hite, 6 Indiana, 428, 1855; Sone v. Palmer, 28 Missouri, 539, 1859.

1850

Gibson v. Cook, 2 Blatch. 144,

8 Peck v. Bacon, 18 Connecticut, 377, 1847; Continental Windmill Co. v. Empire Windmill Co. 8 Blatch. 295, 1871; Ashcroft v. Walworth, 1 Holmes, 152, 1872.

for the assignment which he took.

A merely good con

sideration will, therefore, not support an assignment as against any prior unrecorded assignment of the same patent given for a valuable consideration.

The notice which will protect a prior unrecorded assignment, against a subsequent assignment for a valuable consideration, may be actual, or it may be constructive only. Such constructive notice may be based on the fact that the subsequent assignee was informed, at the time of his purchase, that the prior assignee was making, using, or selling specimens of the invention covered by the patent involved. Such making, using, or selling is such a possession of the invention, as charges all purchasers who are cognizant thereof, with notice of whatever title the maker, user, or seller may possess.' Whether such constructive notice may also be based on the fact that the subsequent purchaser was a corporation in which the assignor was a director, is a question upon which the precedents are now opposing." Where title has once vested in a subsequent purchaser, for a valuable consideration, without notice of a prior unrecorded assignment more than three months old; that title becomes absolute, and may be purchased by persons who had actual knowledge of the prior assignment. If this rule were otherwise, titles thus derived might become valueless for want of qualified purchasers."

The foregoing parts of this section contemplate cases where the things covered by several assignments of the same assignors, are unquestionably identical; and where there is no ground for controversy relevant to the respective dates of the conflicting transactions. Where either or both

Saxton v. Aultman, 15 Ohio State, 471, 1864.

2 Prime v. Mfg. Co. 16 Blatch. 455, 1879.

3 Continental Windmill Co. v. Empire Windmill Co. 8 Blatch. 295, 1871; Cutter Co. v. Sheldon, 10 Blatch. 1, 1872; Davis Wheel Co.

v. Davis Wagon Co. 20 Fed. Rep. 700, 1884.

Wright . Randel, 8 Fed. Rep. 599, 1881.

5 Varick v. Briggs, 6 Paige (N. Y.), 329, 1837; Story's Equity Jurisprudence, Section 1503a.

of those circumstances are otherwise, other points of law will also arise. Where, for example, the subsequent assignment purported to convey no more than the right, title, and interest of the assignor, in the specified patent, that assignment can never prevail against any prior unrecorded assignment which left any interest in the assignor;' if indeed it can prevail against one which left no such interest."

The date of an assignment is the day of its delivery, and not the date which appears upon its face, if the latter differs from the former;' and the three months within which, after that date, an assignment is required to be recorded, are lunar, and not calendar months."

$282. Warranty of title is implied in every assignment of a patent right unless that assignment purports to convey merely the right of the assignor; or unless it is otherwise limited to narrower ground than the entire patent right which it describes. Every such assignment will therefore transfer whatever title the assignor may subsequently acquire by purchase or otherwise.' But an assignment of the right, title, and interest of the assignor without anything more, will not operate to convey any title which is subsequently acquired by him."

§ 283. No warranty of validity is implied in any assignment of a patent right. If the assignor knows the patent to be invalid, at the time he makes the assignment, he is guilty of fraud, and the assignee may have relief against him, on that ground; but if both parties are equally innocent of knowledge of invalidity, the loss consequent on any invalidity afterward brought to light, must fall upon the then owner of the patent."

1 Brown v. Jackson, 3 Wheaton, 449, 1818; Ashcroft . Walworth, 1 Holmes, 152, 1872; Turnbull v. Plow Co. 6 Bissell, 230, 1874.

Oliver . Piatt, 3 Howard, 363, 1845; May . Le Claire, 11 Wallace, 232, 1870.

Dyer v. Rich, 1 Metcalf (Mass.), 180, 1840.

4 Section 125 of this book.

5 Faulks v. Kamp, 17 Blatch. 433, 1880.

1870.

Perry v. Corning, 7 Blatch. 195,

Hiatt v. Twomey, 1 Devereux & Battle's Equity Cases (N. C.), 315, 1836; Cansler v. Eaton, 2 Jones' Equity Cases (N. C.), 499, 1856.

Some State courts have held, that when sued by an assignor for the purchase price of a patent, any assignee may defend on any ground of invalidity which he can prove to exist. This view is based on the theory that in such a case there is a failure of consideration. This theory is not correct, because an assignor may lose, and an assignee may gain as much on account of the assignment of an invalid patent as on account of a valid one. An assignment of an invalid patent is a sufficient consideration to support a promissory note, in any case where there is neither warranty nor fraud.' To allow an assignee, who has made profit from the patent assigned, to defend against a suit for the promised price, on the ground of some defect he has been able to discover in the patent, would be very unjust.' Such a rule might enable an assignee to reap enormous gains from practically exclusive rights, and then to avert payment for those rights, on some far-fetched ground of invalidity, which never for one moment had disturbed his exclusive possession of the patented privilege. Even where an assignee is not shown to have derived any benefit from the assignment of a particular patent, he ought not to be permitted to defend against a suit for the price he promised to pay therefor; because that assignment operated, at least to prevent the assignor from making, using, or selling specimens of the patented thing. It is perfectly well settled that loss or disadvantage to the promisee, is a sufficient consideration to support a contract, even where that contract resulted in no benefit to the promisor.'

§ 284. Express warranties of validity may of course be incorporated in assignments of patents; and, where so incorporated, they will subject assignors to actions for damages, if the patents assigned are found to be in fact invalid. Parol warranties of validity, when they accompany

1 Thomas v. Quintard, 5 Duer (N. Y.), 80, 1855.

Milligan . Mfg. Co. 21 Fed. Rep. 570, 1884.

Parsons on Contracts, Book 2, Ch. 1, Sec. 2.

Wright. Wilson, 11 Richardson (S. C. Law Reports), 151, 1856.