This is an action upon a promissory note. It appeared that defendant had made an invention for purifying flour middlings, and having applied for letters patent for the *540same, had assigned a half interest therein to plaintiff. Subsequently plaintiff and defendant made an agreement, by the terms of which plaintiff was to re-assign his half interest to defendant, and to request the commissioner of patents to issue a patent for the invention in defendant’s sole name, in consideration whereof defendant was to give plaintiff his check for $320, and execute the note in suit. This agreement was fully performed on both sides, the plaintiff executing an instrument, by the terms of which he sold, re-assigned and set over to defendant all Ms interest in the invention as before assigned by defendant to him. He also, in the instrument of re-assignment, requested the commissioner of patents to cancel the assignment to himself, and to issue letters patent for the invention in the sole name of defendant. The instrument of re-assignment was duly recorded in the patent office.
As a defence, and for the purpose, as we understand it, of showing a failure of the consideration of the note, the defendant offered to prove a breach of the agreement on account of which the note was given, by showing that, after the re-assignment, a patent was issued to the plaintiff for a portion of the theory of the invention originally assigned to him by defendant, and that defendant’s subsequent application for a patent for his invention was rejected, on the ground that it would infringe upon the patent issued to plaintiff. There is nothing in the defence. The re-assignment had respect solely to defendant’s rights under his supposed invention, whatever they might be. The plaintiff in no way became responsible for the validity of defendant’s claim of an invention, neither did he guaranty the issue of a patent for the same. The issue of the patent to plaintiff does not show that plaintiff in any way interfered with any rights of defendant. On the contrary, as the patent is to be taken to have been rightfully issued, it is to be presumed that plaintiff was entitled to the same, (as he might be,) without any interference with defendant’s rights. Judgment affirmed.