Viewed in the light of the admitted facts, the only question in the case is whether the assignment by the plaintiff to a third person of an undivided half of the right, title, and interest secured to him by his letters patent, subsequent to the alleged infringement, but before the commencement of his suit, is a bar to his claim to recover damages for such infringement.
Letters patent were granted to the plaintiff on the 18th of April, 1848, for a certain new and useful improvement in grain drills, in which it is alleged that he is the original and first inventor of the improvement. Original patent was for the term of fourteen years, but it was subsequently extended by the Commissioner of Patents for the term of seven years from and after the expiration of the original term. Alleged defects existed in the original specification, and in consequence thereof, the plaintiff, on the 3d of February, 1863, surrendered the letters patent, and the same were reissued to him in three new patents for separate and distinct parts of the invention for the unexpired portion of the original and extended terms of the patent.
Damages are claimed of the defendants for infringing the reissued letters patent from the day of the reissue to the 24th of February, 1865, as more fully set forth in the declaration.
Pleas to the declaration were subsequently filed by the defendants, and the record shows that they gave due notice of certain special defences which they proposed to offer in evidence under the general issue, in pursuance of the act of Congress in such case made and provided. Before the day for the trial came, however, the parties filed an agreement waiving a jury and submitting the cause to the court, stipulating that the decision of the court should have the same effect as the verdict of a jury. Leave to amend was subsequently granted by the court to both parties.
Purport of the amendment to the declaration was, that the plaintiff was the sole owner of the letters patent for the county of Union, in the State of Pennsylvania, from the date of the reissued letters patent to the 24th of February, 1865, and that the defendants had infringed the same throughout that period, by making and using the invention, and vending the same to others to be used without his license or consent.
Defendants filed another special plea, in which they alleged that the plaintiff, when he commenced his suit, was not the owner of the exclusive right secured in the reissued letters patent within any part of the United States; that in certain States and districts he had parted with all his interest in the patent; and that, on the said 24th of February, he assigned and transferred an undivided half of all the residue of his right, title, and interest in the same, and, therefore, that the plaintiff had no right to bring this action in his own name against the defendants. Plaintiff demurred to the plea, and the defendants joined in demurrer. Parties were heard, and the court rendered judgment for the defendants, and the plaintiff sued out this writ of error.
Conceded fact is, that the plaintiff was the exclusive owner of the patent in the territorial district where the alleged infringement was committed, throughout the entire period of the infringement, as alleged in the declaration. Express allegation of the declaration is to that effect, and, as the plea is in avoidance and contains no denial of the matters alleged in the declaration, they must be considered as admitted, unless the matters alleged in the special plea are a sufficient answer to the action.
Briefly stated, the matter alleged in avoidance of the right of the plaintiff to maintain the suit is, that he, before he commenced the suit, but subsequent to the infringement, sold and assigned an undivided half of his patent for the territorial district where the infringement was committed, to a third person.
Patentees have secured to them, by virtue of the letters patent granted to them, the full and exclusive right and liberty, for a prescribed term, 'of making and using, and vending to others to be used,' their respective inventions or discoveries; and, whenever their rights, as thus defined, are invaded by others, they are entitled to an action on the case to recover actual damages as compensation for the injury.
Such damages may be recovered by action on the case in any Circuit Court of competent jurisdiction, to be brought in the name or names of the person or persons interested, whether as patentees, assignees, or as grantees of the exclusive right, as already defined, within and throughout a specified part of the United States.