Justice Souter, delivered the opinion of the Court.
The question here is whether the interpretation of a socalled patent claim, the portion of the patent document that defines the scope of the patentee's rights, is a matter of law reserved entirely for the court, or subject to a Seventh Amendment guarantee that a jury will determine the meaning of any disputed term of art about which expert testimony is offered. We hold that the construction of a patent, including terms of art within its claim, is exclusively within the province of the court.
The Constitution empowers Congress "[t]o promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries." Art. I, § 8, cl. 8. Congress first exercised this authority in 1790, when it provided for the issuance of "letters patent," Act of Apr. 10, 1790, ch. 7, § 1, 1 Stat. 109, which, like their modern counterparts, granted inventors "the right to exclude others from making, using, offering for sale, selling, or importing the patented invention," in exchange for full disclosure of an invention, H. Schwartz, Patent Law and Practice 1, 33 (2d ed. 1995). It has long been understood that a patent must describe the exact scope of an invention and its manufacture to "secure to [the patentee] all to which he is entitled, [and] to apprise the public of what is still open to them." McClain v. Ortmayer, 141 U.S. 419, 424 (1891). Under the modern American system, these objectives are served by two distinct elements of a patent document. First, it contains a specification describing the invention "in such full, clear, concise, and exact terms as to enable any person skilled in the art . . . to make and use the same." 35 U. S. C. § 112; see also 3 E. Lipscomb, Walker on Patents § 10:1, pp. 183-184 (3d ed. 1985) (Lipscomb) (listing the requirements for a specification). Second, a patent includes one or more "claims," which "particularly poin[t] out and distinctly clai[m] the subject matter which the applicant regards as his invention." 35 U. S. C. § 112. "A claim covers and secures a process, a machine, a manufacture, a composition of matter, or a design, but never the function or result of either, nor the scientific explanation of their operation." 6 Lipscomb § 21:17, at 315— 316. The claim "define[s] the scope of a patent grant," 3 id., § 11:1, at 280, and functions to forbid not only exact copies of an invention, but products that go to "the heart of an invention but avoids the literal language of the claim by making a
Characteristically, patent lawsuits charge what is known as infringement, Schwartz, supra, at 75, and rest on allegations that the defendant "without authority ma[de], use[d] or [sold the] patented invention, within the United States during the term of the patent there for . . . ." 35 U. S. C. § 271(a). Victory in an infringement suit requires a finding that the patent claim "covers the alleged infringer's product or process," which in turn necessitates a determination of "what the words in the claim mean." Schwartz, supra, at 80; see also 3 Lipscomb § 11:2, at 288-290.
Petitioner in this infringement suit, Markman, owns United States Reissue Patent No. 33,054 for his "Inventory Control and Reporting System for Drycleaning Stores." The patent describes a system that can monitor and report the status, location, and movement of clothing in a drycleaning establishment. The Markman system consists of a keyboard and data processor to generate written records for each transaction, including a bar code readable by optical detectors operated by employees, who log the progress of clothing through the dry-cleaning process. Respondent Westview's product also includes a keyboard and processor, and it lists charges for the dry-cleaning services on bar-coded tickets that can be read by portable optical detectors.
Markman brought an infringement suit against Westview and Althon Enterprises, an operator of dry-cleaning establishments
After the jury compared the patent to Westview's device, it found an infringement of Markman's independent claim 1 and dependent claim 10.
The Seventh Amendment provides that "[i]n Suits at common law, where the value in controversy shall exceed twenty dollars, the right of trial by jury shall be preserved . . . ." U. S. Const., Amdt. 7. Since Justice Story's day, United States v. Wonson, 28 F. Cas. 745, 750 (No. 16,750) (CC Mass. 1812), we have understood that "[t]he right of trial by jury thus preserved is the right which existed under the English common law when the Amendment was adopted." Baltimore & Carolina Line, Inc. v. Redman, 295 U.S. 654, 657 (1935). In keeping with our longstanding adherence to this "historical test," Wolfram, The Constitutional History of the Seventh Amendment, 57 Minn. L. Rev. 639, 640-643 (1973), we ask, first, whether we are dealing with a cause of action that either was tried at law at the time of the founding or is at least analogous to one that was, see, e. g., Tull v. United States, 481 U.S. 412, 417 (1987). If the action in question belongs in the law category, we then ask whether the particular trial decision must fall to the jury in order to preserve the substance of the common-law right as it existed in 1791. See infra, at 377-378.
As to the first issue, going to the character of the cause of action, "[t]he form of our analysis is familiar. `First we compare the statutory action to 18th-century actions brought in the courts of England prior to the merger of the courts of law and equity.' " Granfinanciera, S. A. v. Nordberg, 492 U.S. 33, 42 (1989) (citation omitted). Equally familiar is the descent of today's patent infringement action from the infringement actions tried at law in the 18th century, and there is no dispute that infringement cases today must be tried to a jury, as their predecessors were more than two centuries ago. See, e. g., Bramah v. Hardcastle, 1 Carp. P. C. 168 (K. B. 1789).
This conclusion raises the second question, whether a particular issue occurring within a jury trial (here the construction of a patent claim) is itself necessarily a jury issue, the guarantee being essential to preserve the right to a jury's resolution of the ultimate dispute. In some instances the answer to this second question may be easy because of clear historical evidence that the very subsidiary question was so regarded under the English practice of leaving the issue for a jury. But when, as here, the old practice provides no clear answer, see infra, at 378-380, we are forced to make a judgment about the scope of the Seventh Amendment guarantee without the benefit of any foolproof test.
The Court has repeatedly said that the answer to the second question "must depend on whether the jury must shoulder this responsibility as necessary to preserve the `substance of the common-law right of trial by jury. ` " Tull v. United States, supra, at 426 (emphasis added) (quoting Colgrove v. Battin, 413 U.S. 149, 157 (1973)); see also Baltimore & Carolina Line, supra, at 657. "` "Only those incidents which are regarded as fundamental, as inherent in and of the essence of the system of trial by jury, are placed beyond
The "substance of the common-law right" is, however, a pretty blunt instrument for drawing distinctions. We have tried to sharpen it, to be sure, by reference to the distinction between substance and procedure. See Baltimore & Carolina Line, supra, at 657; see also Galloway v. United States, supra, at 390-391; Ex parte Peterson, 253 U.S. 300, 309 (1920); Walker v. New Mexico & Southern Pacific R. Co., 165 U.S. 593, 596 (1897); but see Sun Oil Co. v. Wortman, 486 U.S. 717, 727 (1988). We have also spoken of the line as one between issues of fact and law. See Baltimore & Carolina Line, supra, at 657; see also Ex parte Peterson, supra, at 310; Walker v. New Mexico & Southern Pacific R. Co., supra, at 597; but see Pullman-Standard v. Swint, 456 U.S. 273, 288 (1982).
But the sounder course, when available, is to classify a mongrel practice (like construing a term of art following receipt of evidence) by using the historical method, much as we do in characterizing the suits and actions within which they arise. Where there is no exact antecedent, the best hope lies in comparing the modern practice to earlier ones whose allocation to court or jury we do know, cf. Baltimore & Carolina Line, supra, at 659, 660; Dimick v. Schiedt, 293 U.S. 474, 477, 482 (1935), seeking the best analogy we can draw between an old and the new, see Tull v. United States, supra, at 420-421 (we must search the English common law for "appropriate analogies" rather than a "precisely analogous common-law cause of action").
"Prior to 1790 nothing in the nature of a claim had appeared either in British patent practice or in that of the
At the time relevant for Seventh Amendment analogies, in contrast, it was the specification, itself a relatively new development, H. Dutton, The Patent System and Inventive Activity During the Industrial Revolution, 1750-1852, pp. 75-76 (1984), that represented the key to the patent. Thus, patent litigation in that early period was typified by so-called novelty actions, testing whether "any essential part of [the patent had been] disclosed to the public before," Huddart v. Grimshaw, Dav. Pat. Cas. 265, 298 (K. B. 1803), and "enablement" cases, in which juries were asked to determine whether the specification described the invention well enough to allow members of the appropriate trade to reproduce it, see, e. g., Arkwright v. Nightingale, Dav. Pat. Cas. 37, 60 (C. P. 1785).
The closest 18th-century analogue of modern claim construction seems, then, to have been the construction of specifications, and as to that function the mere smattering
Markman seeks to supply what the early case reports lack in so many words by relying on decisions like Turner v. Winter, 1 T. R. 602, 99 Eng. Rep. 1274 (K. B. 1787), and Arkwright v. Nightingale, Dav. Pat. Cas. 37 (C. P. 1785), to argue that the 18th-century juries must have acted as definers of patent terms just to reach the verdicts we know they rendered in patent cases turning on enablement or novelty. But the conclusion simply does not follow. There is no more reason to infer that juries supplied plenary interpretation of written instruments in patent litigation than in other cases implicating the meaning of documentary terms, and we do know that in other kinds of cases during this period judges,
Losing, then, on the contention that juries generally had interpretive responsibilities during the 18th century, Markman seeks a different anchor for analogy in the more modest contention that even if judges were charged with construing most terms in the patent, the art of defining terms of art employed in a specification fell within the province of the jury. Again, however, Markman has no authority from the period in question, but relies instead on the later case of Neilson v. Harford, Webs. Pat. Cas. 328 (Exch. 1841). There, an exchange between the judge and the lawyers indicated that although the construction of a patent was ordinarily for the court, id., at 349 (Alderson, B.), judges should "leav[e] the question of words of art to the jury," id., at 350 (Alderson, B.); see also id., at 370 (judgment of the court); Hill v. Evans, 4 De. G. F. & J. 288, 293-294, 45 Eng. Rep. 1195, 1197 (Ch. 1862). Without, however, in any way disparaging the weight to which Baron Alderson's view is entitled, the most we can say is that an English report more than 70 years after the time that concerns us indicates an exception to what probably had been occurring earlier.
Since evidence of common-law practice at the time of the framing does not entail application of the Seventh Amendment's jury guarantee to the construction of the claim document, we must look elsewhere to characterize this determination of meaning in order to allocate it as between court or jury. We accordingly consult existing precedent
The two elements of a simple patent case, construing the patent and determining whether infringement occurred, were characterized by the former patent practitioner, Justice Curtis.
In arguing for a different allocation of responsibility for the first question, Markman relies primarily on two cases, Bischoff v. Wethered, 9 Wall. 812 (1870), and Tucker v. Spalding, 13 Wall. 453 (1872). These are said to show that evidence of the meaning of patent terms was offered to 19thcentury juries, and thus to imply that the meaning of a documentary term was a jury issue whenever it was subject to evidentiary proof. That is not what Markman's cases show, however.
In order to resolve the Bischoff suit implicating the construction of rival patents, we considered "whether the court below was bound to compare the two specifications, and to instruct the jury, as a matter of law, whether the inventions therein described were, or were not, identical." 9 Wall., at 813 (statement of the case). We said it was not bound to do that, on the ground that investing the court with so dispositive a role would improperly eliminate the jury's function in answering the ultimate question of infringement. On that ultimate issue, expert testimony had been admitted on "the nature of the various mechanisms or manufactures described in the different patents produced, and as to the identity or diversity between them." Id., at 814. Although the jury's consideration of that expert testimony in resolving the question of infringement was said to impinge upon the wellestablished principle "that it is the province of the court, and not the jury, to construe the meaning of documentary evidence," id., at 815, we decided that it was not so. We said:
Bischoff does not then, as Markman contends, hold that the use of expert testimony about the meaning of terms of art requires the judge to submit the question of their construction to the jury. It is instead a case in which the Court drew a line between issues of document interpretation and product identification, and held that expert testimony was properly presented to the jury on the latter, ultimate issue, whether the physical objects produced by the patent were identical. The Court did not see the decision as bearing upon the appropriate treatment of disputed terms. As the opinion emphasized, the Court's "view of the case is not intended to, and does not, trench upon the doctrine that the construction of written instruments is the province of the court alone. It is not the construction of the instrument, but the character of the thing invented, which is sought in questions of identity and diversity of inventions. " Id., at 816 (emphasis added). Tucker, the second case proffered by Markman, is to the same effect. Its reasoning rested expressly on Bischoff, and it just as clearly noted that in addressing the ultimate issue of mixed fact and law, it was for the court to "lay down to the jury the law which should govern them." Tucker, supra, at 455.
Virtually the same description of the court's use of evidence in its interpretive role was set out in another contemporary treatise:
In sum, neither Bischoff nor Tucker indicates that juries resolved the meaning of terms of art in construing a patent, and neither case undercuts Justice Curtis's authority.
Where history and precedent provide no clear answers, functional considerations also play their part in the choice between judge and jury to define terms of art. We said in Miller v. Fenton, 474 U.S. 104, 114 (1985), that when an issue "falls somewhere between a pristine legal standard and a simple historical fact, the fact/law distinction at times has turned on a determination that, as a matter of the sound administration of justice, one judicial actor is better positioned than another to decide the issue in question." So it turns out here, for judges, not juries, are the better suited to find the acquired meaning of patent terms.
The construction of written instruments is one of those things that judges often do and are likely to do better than jurors unburdened by training in exegesis. Patent construction in particular "is a special occupation, requiring, like all others, special training and practice. The judge, from his training and discipline, is more likely to give a proper
Markman would trump these considerations with his argument that a jury should decide a question of meaning peculiar to a trade or profession simply because the question is a subject of testimony requiring credibility determinations, which are the jury's forte. It is, of course, true that credibility judgments have to be made about the experts who testify in patent cases, and in theory there could be a case in which a simple credibility judgment would suffice to choose between experts whose testimony was equally consistent with a patent's internal logic. But our own experience with document construction leaves us doubtful that trial courts will run into many cases like that. In the main, we expect, any credibility determinations will be subsumed within the necessarily sophisticated analysis of the whole document, required by the standard construction rule that a term can be defined only in a way that comports with the instrument as a whole. See Bates v. Coe, 98 U.S. 31, 38 (1878); 6 Lipscomb § 21:40, at 393; 2 Robinson, supra, § 734, at 484; Woodward, supra, at 765; cf. U. S. Industrial Chemicals, Inc. v. Carbide & Carbon Chemicals Co., 315 U.S. 668, 678 (1942); cf. 6 Lipscomb § 21:40, at 393. Thus, in these cases a jury's capabilities to evaluate demeanor, cf. Miller, supra, at 114, 117, to sense the "mainsprings of human conduct," Commissioner v. Duberstein, 363 U.S. 278, 289 (1960), or to reflect community
Finally, we see the importance of uniformity in the treatment of a given patent as an independent reason to allocate all issues of construction to the court. As we noted in General Elec. Co. v. Wabash Appliance Corp., 304 U.S. 364, 369 (1938), "[t]he limits of a patent must be known for the protection of the patentee, the encouragement of the inventive genius of others and the assurance that the subject of the patent will be dedicated ultimately to the public." Otherwise, a "zone of uncertainty which enterprise and experimentation may enter only at the risk of infringement claims would discourage invention only a little less than unequivocal foreclosure of the field," United Carbon Co. v. Binney & Smith Co., 317 U.S. 228, 236 (1942), and "[t]he public [would] be deprived of rights supposed to belong to it, without being clearly told what it is that limits these rights." Merrill v. Yeomans, 94 U.S. 568, 573 (1877). It was just for the sake of such desirable uniformity that Congress created the Court of Appeals for the Federal Circuit as an exclusive appellate court for patent cases, H. R. Rep. No. 97-312, pp. 20-23 (1981), observing that increased uniformity would "strengthen the United States patent system in such a way as to foster technological growth and industrial innovation." Id., at 20.
* * *
Accordingly, we hold that the interpretation of the word "inventory" in this case is an issue for the judge, not the jury, and affirm the decision of the Court of Appeals for the Federal Circuit.
It is so ordered.
Briefs of amici curiae urging affirmance were filed for the American Intellectual Property Law Association by Don W. Martens, Charles L. Gholz, R. Carl Moy, Roger W. Parkhurst, Joseph R. Re, Paul A. Stewart, and Harold C. Wegner; for the Federal Circuit Bar Association by David H. T. Kane and Rudolph P. Hofmann; for the Dallas-Fort Worth Intellectual Property Law Association; for Honeywell, Inc., by Richard G. Taranto and David L. Shapiro; for Intellectual Property Owners by Rex E. Lee, Carter G. Phillips, Mark E. Haddad, and Constantine L. Trela; for Matsushita Electric Corp. of America et al. by Morton Amster and Joel E. Lutzker; for United States Surgical Corp. by John G. Kester, J. Alan Galbraith, William E. McDaniels, Arthur R. Miller, Thomas R. Bremer, and John C. Andres; for John T. Roberts, pro se; and for Douglas W. Wyatt by Mr. Wyatt, pro se, Paul M. Janicke, and John R. Kirk, Jr.
Briefs of amici curiae were filed for Airtouch Communications, Inc., by Allan N. Littman and Robert P. Taylor; for the American Automobile Manufacturers Association by Charles W. Bradley, Stanley L. Amberg, Phillip D. Brady, and Andrew D. Koblenz; for the American Board of Trial Advocates by Robert G. Vial; for Exxon Corp. et al. by Donald B. Craven, Gerald Goldman, James P. Tuite, and James R. Lovelace; and for Litton Systems, Inc., by Laurence H. Tribe, Jonathan S. Massey, and Kenneth J. Chesebro.
"With regard to the second part of this objection, that which claims for the jury the construction of the patent, we remark that the patent itself must be taken as evidence of its meaning; that, like other written instruments, it must be interpreted as a whole . . . and the legal deductions drawn therefrom must be conformable with the scope and purpose of the entire document. This construction and these deductions we hold to be within the exclusive province of the court."