The ground of defence in the action in which this decision was made, was that the specification did not contain a description of the invention in full, clear and exact terms; though the defect did not appear to have arisen from any intention to deceive the public. Marshall C. J. "Courts did not, perhaps, at first distinguish clearly between a defence which would authorize a verdict and judgment in favor of the defendant in the particular action, leaving the plaintiff free to use his patent, and to bring other suits for its infringement; and one which, if successful, would require the court, under the sixth section of the act, to enter a judgment not only for the defendant in the particular case, but one which declares the patent to be void. This distinction is now well settled. The sixth section is not understood to control the third. The evidence of fraudulent intent is required only in the particular case, and for the particular purpose stated in the sixth section. The act of Parliament concerning monopolies contains an exception on which the grants of patents for inventions have issued in that country. The construction of so much of that exception as connects the specification with the patent, and makes the validity of the latter dependent on the correctness of the former, is applicable, we think, to proceedings under the third section of the American act. The English books are full of cases in which it has been held, that a defective specification is a good bar when pleaded to, or a sufficient defence when given in evidence on the general issue, on an action brought for the infringement of a patent right."27 The ground of a similar interpretation is taken away in the law of 1836, since it contains no provision for declaring the patent void in such an action. The question then comes up under that law, what is the construction and effect of the 15th section? One thing is plain, that it does not preclude all other defences than those enumerated, for it does not provide for the case of an obscure specification from which it is not practicable to say what was patented, and yet the defence must be admissible in such a case, first, because the plaintiff cannot recover for violating a privilege which is not intelligibly described, and so cannot be known; and second, because the sixth section of the same act requires that the patentee shall give a description in full, clear and exact terms, and the court cannot disregard this provision. The notion might be suggested that the commissioner is to decide conclusively on the sufficiency of the specification in this respect, and his making out the patent is a certificate of his decision. But this construction is by no means admissible or practicable, for neither the court or jury can say that a privilege is infringed, of which no intelligible description is given. 27 Grant v. Raymond, 6 Peters's S. C. R. 218. It is another defence not enumerated, that the plaintiff is not assignee; or that his assignment is not recorded. But what proves conclusively that all the admissible defences are not enumerated in this section of the law of 1836, is, that the defence that the defendant never made, used or sold the thing patented, is not enumerated. If, then, the section does not preclude all other than the enumerated defences, what is its construction? We shall find an answer to this inquiry in the decisions on the sixth section of the act of 1793, the languaage of which, in respect to the particular question under consideration was similar, viz. the defendant "shall be permitted" to give in evidence on the general issue such and such grounds of defence, of which notice had been given to the plaintiff. On that section Mr. Chief Justice Marshall, giving the opinion of the court, said, "The 6th section of the act appears to be drawn on the idea that the defendant would not be at liberty to contest the validity of the patent on the general issue. It therefore intends to relieve the defendant from the difficulties of pleading, when it allows him to give in evidence matter which does affect the patent. But the notice is directed for the security of the plaintiff, and to protect him against that surprise to which he might be exposed, from an unfair use of this privilege. The notice is substituted for a special plea; it is further to be observed, that it is a substitute to which the defendant is not obliged to resort. The notice is to be given only when it is intended to offer the special matter in evidence on the general issue. The defendant is not obliged to pursue this course. He may still plead specially, and then the plea is the only notice which the plaintiff can claim. ''28 So in a later case the same court says, "The defendant is permitted to proceed according to the sixth section, but is not prohibited from proceeding in the usual manner, so far as respects his defence; except that special matter may not be given in evidence on the general issue unaccompanied by the notice which the sixth section requires.' 729 The effect of the fifteenth section of the act of 1836, then, is, that in making the defences enumerated therein, the defendant must either plead specially or plead the general issue and give the notice required. 28 Evans v. Eaton, 3 Wheaton, 454; and see Evans v. Kremer, 1 Pet. C. C. R. 215, and 3 Wheat. 803, n. 29 Grant v. Raymond, 6 Pet. S. C. R. 746. CHAPTER XX. Evidence in an Action for an Infringement. Sec. 1. On the part of the Plaintiff. 2. On the part of the Defendant. Sec. I. ON THE PART OF THE PLAINTIFF. WHERE the defendant pleads the usual plea of the general issue, the first evidence produced by the plaintiff, in an action for an infringement, is the patent and specification, and the assignment of the patent, if it be assigned. Certified copies of these from the patent office are made evidence.' In England the enrollment of the specification in due time must also be proved.2 Where the patent was for an improvement on a machine previously patented, Lord Tenterden ruled that the specifications of both inventions must be given in evidence. He said he would not say "what are improvements on a given thing without knowing what the thing was before." But this must cer 1 Stat. of 1836, s. 4. 2 Watson v. Pears, 2 Camp. R. 294. 3 Lewis v. Davis, 3 C. and P. 502. |