upon the privileges of the licensee, however, differs according to the right which forms the subject-matter of the license, and the class to which the patented invention properly belongs. If the invention is an instrument a license to make it, or to sell it, expires with the original term of the patent, and no further manufacture or sale will be lawful without a license. under the extension. But a license to make and use, or a license to use a particular instrument manufactured under the patent and duly sold to the licensee, remains in force, so far as the use is concerned, until the instrument made or purchased is worn out and can no longer be repaired without destroying its identity.5 A license to use a certain number tension thereof, securing the exclusive right to the same invention which was the subject of the sale.' In the present case neither the invention, nor any interest in it, nor any interest in the entire right covered by the patent was granted, but merely a license to use the invention, and to construct brakes containing it for such use on certain cars, on a certain railroad; and such license is to continue during the term for which said letters-patent are or may be granted. The term for which said letters-patent - that is, the letters-patent granted October 2d, 1849, and re-issued March 1st, 1853- were granted, or might be granted, was a term ending October 2d, 1863. It is impossible, on any fair construction of the language, and in view of the adjudged cases, to hold that the license was intended by the parties to cover an extended term of the patent." 3 Fisher, 410 (414). See also Wetherell v. Passaic Zinc Co. (1872), 6 Fisher, 50; 2 O. G. 471; 9 Phila. 385. 4 That a license to make or to sell, or to make and sell, a patented article expires with the original patent unless otherwise provided in the license, see Mitchell v. Hawley (1872), 16 Wall. 544; 3 O. G. 241; 6 Fisher, 331; Wood v. Michigan Southern R. R. Co. (1868), 2 Bissell, 62; 3 Fisher, 464. That a license to make, use, and sell runs for the term of the patent, see Birdsell v. Shaliol (1884), 112 U. S. 485; 30 O. G. 261. 5 In Mitchell v. Hawley (1872), 16. Wall. 544, Clifford, J. (548) "Purchasers of the exclusive privilege of making or vending the patented machine hold the whole or a portion of the franchise which the patent secures, depending upon the nature of the conveyance; and of course the interest which the purchaser acquires terminates at the time limited for its continuance by the law which created the franchise, unless it is expressly stipulated to the contrary. But the purchaser of the implement or machine for the purpose of using it in the ordinary pursuits of life stands on different grounds, as he does not acquire any right to construct another machine either for his own use or to be vended to another for any purpose. Complete title to the implement or machine purchased becomes vested in the vendee by the sale and purchase; but he acquires no portion of the franchise, as the machine when it rightfully passes from the patentee to the purchaser, ceases to be within the limits of the monopoly." 3 0. G. 241 (242); 6 Fisher, 331 (333). In Wetherell v. Passaic Zinc Co. (1872), 2 O. G. 471, McKennan, J.: of patented instruments in like manner confers upon the licensee the right to keep that number in employment during (474) "A broad distinction is thus indicated between the use of an invention and the use of a patented machine. While the right to the use of the invention expires with the end of the term of the original patent, the right to the continued use of the machine which embodies it is protected. The law did not intend to revive an assignment or grant which expired with the term of the original patent, but to protect a species of tangible property, sold by the patentee, the value of which depended chiefly upon the owner's right to use it, and which, without some saving provision, would fall within the grasp of the exclusive rights vested in the patentee by the extension. It was manifestly, then, something less than the entire right to use the invention which the act contemplated. What that is is clearly stated in the opinion of the court, not as a dictum of the judge who delivered it, but as an exposition of the meaning of the act, which was necessary to a decision of the cause. 'The thing patented' is the subject of the use, and the court say, where these words are employed in the act in connection simply with the right to use, they refer only to the patented machine, and not to the invention. This, then, is an authoritative definition of their significance in the clause in question, and they must therefore be taken to mean a specific machine, and, in connection with the other words of the clause, to confer a right to use it, 'nothing more.' And it has since been held that this right is restricted to the mere use, and does not cover the reconstruction of the machine. It necessarily follows that this saving clause is applicable only to inventions which are susceptible of embodiment in a substantial and tangible form, and not to those which consist in a formula for producing prescribed results, and when those results are obtained there is an end of the thing patented, and which, as often as it is employed in. practice, involves the renewed use or reproduction of the entire invention.' 6 Fisher, 50 (58); 9 Phila. 385 (389). In Hawley v. Mitchell (1871), 1 0. G. 306, Shepley, J.: (307) "No words of limitation, however clearly expressed, confining an assignee's right to the original term, will have any effect to deprive the assignee or his assigns of the right to use, during the extended term of the patent, machines lawfully constructed and used by them during the original term. But this right applies only to machines which have passed outside of the monopoly by a lawful sale of the whole monopoly in the particular machine during the original term." Holmes, 42 (44); 4 Fisher, 388 (390). In Wood v. Michigan Southern & Northern Indiana R. R. Co. (1868), 2 Bissell, 62, McDonald, J.: (65) "To every assignee or grantee of a patent holding the right, at the expiration of the first term of it, to use the thing patented, this section of the act plainly gives the same right to use it during the term of the renewal of the patent, exactly to the extent to which he had the right to use it under the first term of the patent. And it is clear that he may not only use it, but repair it for use till it is worn out. So the Supreme Court has decided. On the contrary, it is equally clear that this section does not authorize the assignee or grantee either to sell or to manufacture for sale the thing patented; for the terms of the section only embrace assignees and grantees of the right to use.'. . . (67) The same doctrine was adhered to in the original term, to replace them with others as they become unserviceable, and to use those actually on hand when the patent expires until they are no longer capable of use. A general license to use the invention, having no reference to particular instruments or to a specific number of the patented articles, and not granted in connection with an unrestricted sale of Wilson r. Simpson, 9 How. 109. And Mr. Justice Wayne, in delivering the opinion of the court in that case, said that the decision in Wilson v. Rousseau 'does not permit an assignee of the first term of a patent, after its renewal and extension, to make other machines.' The subsequent cases of Bloomer v. McQuewan, 14 How. 539; Chaffee v. The Boston Belting Co., 22 How. 217; Bloomer v. Millinger, 1 Wallace, 340,— all recognize and approve the same doctrine. The doctrine established in all these cases is that an assignee of a patent holding, at the expiration of the first term, a right during that term to make and use the thing patented, may during the time of its subsequent extension, continue to use it, and even repair it for use; but that he cannot make it for use, or for any other purpose. It is true that in the cases in the Supreme Court referred to, there was a remarkable diversity of opinion among the judges. But that diversity had no reference to anything favorable to the defence in this case. It seems to have arisen solely from an opinion, on the part of the minority of the judges, that the assignee of a patent for its first term had no right even to use the thing patented after the expiration of that terni, unless the assignment, by its terms, gave him that right. And this circumstance may well admonish us not to extend this right to the thing patented." 3 Fisher, 464 (468). 18 Wall. 414; 5 O. G. 95; Brooks v. Bicknell (1845), 4 McLean, 64. That the right to use includes the right to repair and to purchase new when the old are worn out, see Bicknell v. Todd (1851), 5 McLean, 236. That a right to use subsists with the same limitations as to place, etc., after an extension as before, see Day v. Union India Rubber Co. (1856), 3 Blatch. 488. That the owners of an extension and their grantees take their title subject to the rights of the existing owners of the patented devices, see Union Paper Bag Mach. Co. v. Nixon (1882), 105 U. S. 766; 21 O. G. 1275. That a licensee is neither an assignee nor a grantee, under Sec. 4928, Rev. Stat., but must be a purchaser of the patented article or be protected by some agreement of sale lawfully made by the owner of the patent, see Wooster v. Sidenberg (1875), 10 O. G. 244; 13 Blatch 88; 2 Bann. & A. 91. That where an agent of the patentee, for a valuable consideration, licenses another to construct a device embody. ing the invention, the patentee has no right to the device, but the licensee may use the invention in connection with such device even under an extension, see Black v. Hubbard (1877), 3 Bann. & A. 39; 12 0. G. 842. That a license to use one device is a license to make one for use and to use it until it is worn out, and to sup. ply its place with another and so on, till the patent expires, and then to use the one at that time in use until it is also worn out, see Woodworth v. Curtis (1847), 2 W. & M. 524; 2 Robb, 603. See also Union Paper Bag Mach. Co. v. Nixon (1882), 105 U. S. 766; 21 O. G. 1275; Eunson v. Dodge (1873), the patented article, on the contrary, expires with the patent.7 If the invention is an art, a license to use it is a license to practise the invention as a whole, and in analogy with the preceding rules should also terminate with the original patent.8 But it has been held that such a license granted by the patentee, or by an assignee to whom the extension has already been conveyed, continues during the extended term and authorizes the licensee not only to employ the process but to procure new apparatus for its use after the extension.9 These various rights the licensee will waive if he takes a new license from the owners of the extended term. 10 A license to a specific person ceases at his death.11 § 817. Express License not Recordable. A license is not such a conveyance of an interest in the patented invention as to affect its ownership, and hence is not required to be recorded.1 7 That a general license to use expires with the patent, see Union Paper Bag Mach. Co. v. Nixon (1882), 105 U. S. 766; 21 O. G. 1275; Wooster v. Sidenberg (1875), 10 O. G. 244; 13 Blatch. 88; 2 Bann. & A. 91. 8 That the grant of a right to use a process, even though coupled with the sale of apparatus suitable for use in that process, does not convey the right to use the process during an extension, see Wetherell v. Passaic Zinc Co. (1872), 2 O. G. 471; 9 Phila. 385; 6 Fisher, 50. 9 That the right to practise a patented process, if derived from the patentee himself, continues during an extension, even against an assignee of the extended term, and even though the licensee makes new apparatus to do it with after the extension, see Day v. Union India Rubber Co. (1856), 3 Blatch. 488. 10 That where a licensee has articles in use at the expiration of the patent, and has the right to use them during the extension and until they are used All subsequent purchasers up, but takes a new license under the extension and forfeits it, his old license cannot avail him even as to these articles, see Wooster v. Taylor (1874), 12 Blatch. 384; 1 Bann. & A. 594; 8 O. G. 644. 11 That a personal license granted for a certain period will expire at the death of the licensee unless also granted to his assigns, see Oliver v. Rumford Chemical Works (1883), 109 U. S. 75; 25 O. G. 784. That under a personal and unassignable license to make and sell, the articles on hand at the death of the licensee may be sold by his representatives, see Montross v. Mabie (1887), 30 Fed. Rep. 234; 41 O. G. 931. § 817. 1 That a license need not be recorded, see Hamilton v. Kingsbury (1879), 17 Blatch. 264; 17 O. G. 147; 4 Bann. & A. 615; Chambers v. Smith (1870), 5 Fisher, 12; Farrington v. Gregory (1870), 4 Fisher, 221; Brooks v. Byam (1843), 2 Story, 525; 2 Robb, 161. take their titles subject to the rights of existing irrevocable licensees, as assignees of other property receive it subject to the obligations imposed upon it by the contracts of its previous owners.2 The value of the patented invention to the vendee may be impaired by such outstanding licenses, but of this he must inform himself at his own risk as best he may. The record of a license, not being legally required, is not con structive notice to any person or for any purpose.3 § 818. Express Licenses: How Construed. A license is construed by the courts according to the intention of the parties, as manifested by the language they employ. If the license is in writing all previous parol agreements covering the same subject-matter are merged in the written instrument, and oral evidence is not admissible to expand, contract, or vary its provisions.2 When several licenses or other contracts constitute together one transaction, all are to be considered in the interpretation of each, as if they were a single instrument. The scope of any license, if general in its terms, is to be limited by the patent on which it is based; and where the conduct of the parties and their dealings with each other have given a practical construction to the conveyance, not inconsistent with its letter, this also is regarded in determining its meaning. A license conferred before the is 2 That an irrevocable license is good without record against subsequent purchasers of the patent, see Farrington v. Gregory (1870), 4 Fisher, 221. 8 That the record of a license is not constructive notice, see Chambers v. Smith (1870), 5 Fisher, 12. § 818. 1 That a license is to be construed by the intent of the parties, see Wetherell v. Passaic Zinc Co. (1872), 2 O. G. 471; 9 Phila. 385; 6 Fisher, 50. That in enforcing a license the courts will follow the contract, not the moral conditions outside it, see Ex parte Fuller (1874), 5 O. G. 643. 2 That a parol agreement, made before a written license, is merged in the license, see Evory v. Candee (1879), 17 Blatch. 200; 4 Bann. & A. 545. That oral evidence is not admissible to explain a written license, but the parties must stand by it as made, see Troy Iron & Nail Factory v. Corning (1849), 1 Blatch. 467. 3 That several contracts for sale and license, made between the same parties on the same day, may all be construed together, see Hammond v. Mason & Hamlin Organ Co. (1875), 92 U. S. 724. 4 That a license is limited in scope by the patent on which it is based, see Stuart v. Shantz (1872), 6 Fisher, 35; 2 O. G. 524. That a license to use the invention |