admissible in a subsequent interference suit between the same parties on the same question of priority.' But Judge SHIRAS has held that such depositions are not thus admissible, where there is no insuperable obstacle to retaking the testimony of the deponents."

3

$319. Injunctions are not expressly authorized by the statute which provides for interference suits. Justice NELSON once decided that a preliminary injunction could be granted in such a case on the ground that "the power conferred upon the Circuit Court to entertain bills in equity, in controversies arising under the Patent Act, is a general equity power, and carries with it all the incidents belonging to that species of jurisdiction." Justice BLATCHFORD was of counsel for defendant in that case, and was its reporter; but when he came to the bench he declined to follow the precedent, saying: "I am not aware of any principle which would authorize the Court, in a suit of this character, to restrain a defendant from bringing suits on his patent, before that patent is adjudged to be invalid." Of course Justice BLATCHFORD was aware of what Justice NELSON had decided. He must therefore have held that the reason Justice NELSON gave was not a good one; unless there is a substantial difference between the forms of injunction asked for in the two cases. The injunction prayed before Justice NELSON was that the defendant be restrained from using or selling his interfering patent; and the injunction prayed in the other case was that the defendant be restrained from bringing suits upon his interfering patent. In both cases the thing sought to be enjoined was an attempted enjoyment of the patented right. The two decisions seem therefore to be in conflict, and the law upon the point cannot be said to be settled.

§ 320. The hearing of an interference case may disclose

11 Greenleaf on Evidence, Section 553.

Clow. Baker, 36 Fed. Rep. 692, 1888.

Potter v. Dixon, 5 Blatch. 165, 1863.

4 Asbestos Felting Co. v. Salamander Felting Co. 13 Blatch. 454, 1876.

that there is no interference between the patents before the court; or that there is such an interference. In the former event, the proper decree to enter is one dismissing the complainant's bill; and in the latter event, the proper decree is one adjudging the patent issued on the later of the inventions, to be void, so far as it secures the interfering matter, and so far as the title of the parties to the suit extends.' Such a decree should be entered regardless of whether the patent to be voided is that of the defendant or that of the complainant. If it is the latter, a decree merely dismissing the complainant's bill will not answer the purpose; because such a decree does not necessarily involve any such conclusion.' It may mean only that there is no interference; or it may merely mean that the complainant has no proper title to the patent which he invokes.

1 Gilmore v. Golay, 3 Fisher, 522, 1869; Sturges v. Van Hagen, 6 Fisher, 572, 1873.

2 Tyler,v. Hyde, 2 Blatch. 310, 1851.

CHAPTER XIV.

REPEAL OF PATENTS.

321. Patents obtained by fraud, or

granted by mistake.

patents so obtained or so granted.

322. Jurisdiction of equity to repeal 323. Practice in such cases.

§ 321. PATENTS and reissues may sometimes be obtained by fraud; and sometimes be granted by mistake. The facts which constitute the fraud, or which make the granting a mistaken one, may generally be interposed as one of the defences to an infringement suit; but where those facts are such that no one of those defences can be based upon them, they cannot be interposed merely because they constitute a fraud,' or constitute a mistake. Nor can any individual

bring any action to repeal or otherwise set aside a patent, on any ground of fraud; or indeed on any ground whatever, except that of an interference.' Where frauds are ingenious enough to keep clear of all known defences to infringement suits, the wrongs which they cause are without a remedy, unless the United States Courts will repeal a patent which United States officers have fraudulently been induced to grant, or to reissue. So also, where a patent is granted by mistake, instead of being refused, as it ought; and where the ground of refusal does not constitute ground of defence to a suit for infringement; the wrongs which such a mistake will occasion must be remedied by a repeal of the patent, or they are remediless.

§ 322. Equity has jurisdiction to repeal letters patent for inventions where they were obtained by fraud, whenever

1 Railroad Co. v. Duboise, 12 Wallace, 64, 1870.

Doughty. West, 6 Blatch. 433,

1869.

3 Mowry v. Whitney, 14 Wallace, 439, 1871.

the United States files a bill stating the facts and praying that the letters may be annulled;' and the same jurisdiction probably exists where such letters patent are issued by mistake.

§ 323. A bill to repeal a patent must be filed by the United States; acting through the United States district attorney of the district wherein it is filed;' and he acts under the direction of the Attorney General of the United States; and it must be filed in the Circuit Court of the United States for that district; and be filed before the expiration of the patent which it seeks to repeal. No citizen has any power to compel the United States or the district attorney to file such a bill; or to control its prosecution after such a bill is filed.' The mere pendency of a bill to repeal a patent will not affect the progress of an infringement suit based on that patent; and no injunction will issue to restrain a patentee from bringing infringement suits, pending a bill in equity to repeal the patent upon which he proposes to bring them."

No

$324. THESE are certain actions at law, which derive their name from the Latin words qui tam, used at the beginning of the declaration in such an action, in times when all declarations were written in the Latin language. such action was known to the common law of England; but several actions of the kind have long been prescribed by statute, in that country, and in this. Qui tam actions relevant to patents are authorized by Section 4901 of the Revised Statutes. That statute forbids certain classes of acts; and provides that whoever commits an act of either of those classes, shall be liable to a penalty of not less than one hundred dollars, with costs; and that any person may sue for that penalty, in any District Court of the United States within whose jurisdiction the offence was committed; and that one half of the penalty, when recovered, shall go to the plaintiff, and the other half to the United States.

§ 325. The forbidden acts are: 1. Unauthorized marking, upon any patented article, of the name, or any imitation of the name, of the patentee. 2. Unauthorized mark