Opinion ID: 428566
Heading Depth: 1
Heading Rank: 2

Heading: mead's infringement of the sweet patent

Text: 28 The infringement issue in this case turns on the application of the doctrine of equivalents, a canon of patent construction sometimes used in infringement cases to determine the scope of patent claims. This doctrine holds that a device is in infringement even if it does not literally infringe the patent if it performs substantially the same function in substantially the same way to obtain the same result. Sanitary Refrigerator Co. v. Winters, 280 U.S. 30, 42, 50 S.Ct. 9, 13, 74 L.Ed. 147 (1929). However, as Justice Jackson noted in Graver Mfg. Co. v. Linde Co., 339 U.S. 605, 608-609, 70 S.Ct. 854, 856, 94 L.Ed. 1097 (1950), the doctrine of equivalents is a two-edged sword: where a device is so far changed in principle from a patented article that it performs the same or similar function in a substantially different way, but nevertheless falls within the literal words of the claim, the doctrine of equivalents may be used to restrict the claim and defeat the patentee's action for infringement. The doctrine thus may be applied in favor of as well as against a patentee. It can be used to hold a device in infringement even though the device does not literally infringe the patent claims; it can be used to hold a device not in infringement even though the device falls within the literal words of the claim. 29 The general purpose of the doctrine is to encourage patentable inventions as well as genuine improvements of existing inventions but to discourage what Justice Jackson in Graver calls unimportant and insubstantial changes and substitutions in the patent which, though adding nothing, would be enough to take the copied matter outside the claim, and hence outside the reach of the law in the absence of a flexible doctrine designed to protect the patentee from insubstantial changes. 339 U.S. at 607, 70 S.Ct. at 855. 30 The doctrine is not the prisoner of a formula, and a finding of equivalents is a determination of fact.... It is to be decided by the trial court and that court's decision, under general principles of appellate review, should not be disturbed unless clearly erroneous. 339 U.S. at 609-10, 70 S.Ct. at 856-57. Judge Hand referred to the doctrine as in misericordiam to relieve those who have failed to express their complete meaning in the patent and stated that its application in each case is inevitably a matter of degree. Claude Neon Lights, Inc. v. E. Machlett's Sons, 36 F.2d 574, 576 (2d Cir.1929). Many courts have said that a patent should be accorded a wider range of equivalents if it represents a major step in the field such that it may be called a pioneer patent. See, e.g., Boyden Power-Brake Co. v. Westinghouse, 170 U.S. 537, 569, 18 S.Ct. 707, 723, 42 L.Ed. 1136 (1898); Acme Highway Product Corp. v. D.S. Brown Co., 473 F.2d 849 (6th Cir.1973). 31 Appellants direct us to the following passage in Graver as controlling: If accused matter falls clearly within the claim, infringement is made out and that is the end of it. 339 U.S. at 607, 70 S.Ct. at 855. This so-called doctrine of literal infringement continues to live in the cases despite repeated pronouncements that infringement is not a mere matter of words. See CHISUM, Patents Sec. 18.04 (1983) and cases cited therein. Indeed, in Graver the Supreme Court indicates that the doctrine of literal infringement is not to be taken literally: two paragraphs after announcing that doctrine the Court recognizes that the doctrine of equivalents applies even when the accused device falls within the literal words of the claim. 339 U.S. at 608-09, 70 S.Ct. at 856. 32 Courts, however unfortunately, continue to pay lip service to the doctrine of literal infringement as though it were the rule in Shelley's Case. Perhaps we are embarrassed to expose the wholesale realism which controls many infringement cases, see 339 U.S. at 608, 70 S.Ct. at 856, and we choose instead to present the facade of precision and certainty which attends the doctrine of literal infringement. 33 As Judge Hand pointed out in Claude Neon Lights, there is no doubt that the doctrine of equivalents violates in theory the underlying and necessary principle that the disclosure is open to the public save as the claim forbids, and that it is the claim and that alone which measures the monopoly. 36 F.2d at 575 (citations omitted). As Hand stated, the doctrine is an anomaly needed to soften and render flexible the rule of literal infringement. 34 The wholesale realism of the doctrine of equivalents means that precedents have little or no value since a decision is bound to have an arbitrary color, as in all close cases of interpretation, and it is difficult to give it greater authority than an appeal to the sympathetic understanding of an impartial reader. Claude Neon Lights, 36 F.2d at 576. This result will not set well with those who demand rules in this area and treat patent law problems as questions of semantics. Settled expectations are an important goal, but the survival of the doctrine of equivalents in this specialized field demonstrates that unsparing logic must be tempered with wholesale realism. See Royal Typewriter Co. v. Remington Rand, Inc., 168 F.2d 691, 692 (2d Cir.1948). 35 With these general legal principles in mind, we now turn to the arguments advanced by appellants to support their assertion that the DIJIT printer infringes the Sweet patent.
36 Appellant's principal argument is that the District Court improperly circumscribed the Sweet patent by its illustrative embodiments: a patent is measured, appellants argue, by its claims and not its specifications or embodiments. Claims 1 and 33 of the Sweet patent, properly understood, extend far beyond oscillography, presumably to all ink jet printers that use the Sweet technique of selectively charging ink droplets. They argue that Sweet's invention consists of five elements--an ink jet generator, an ink jet stimulator, a droplet-charging mechanism, a deflecting mechanism, and a droplet-collection mechanism--and that the DIJIT printer contains and uses all five of these elements in precisely the manner specified in the Sweet patent. Appellant's Brief at 46. Appellants conclude therefore that the Sweet claims read on the DIJIT printer and that infringement follows as a matter of law. 37 Appellants are wrong on two counts. First, a finding of literal infringement is not the end of an infringement inquiry, despite numerous judicial statements to the contrary. 11 As this Court stated in National Rolled Thread Die Co. v. E.W. Ferry Screw Products, Inc., 541 F.2d 593, 600 (6th Cir.1976): 38 Infringement should not be determined by a mere decision that the terms of a claim of a valid patent are applicable to the defendant's device. Two things are not necessarily similar in a practical sense because the same words are applicable to each.... 39 There is no magic in a name, nor in a claim; that the words preferred by a patentee to define his invention apply literally to another's device suggests, but does not prove, infringement; there must be a substantial identity, to justify that conclusion of law. 40 (citations omitted). 41 Put differently, the doctrine of literal infringement is informed by the doctrine of equivalents: in infringement actions the court must consider the substance of the invention along with the form of the claims. Thus, even were we to determine that the DIJIT printer reads on claims 1 and 33 of the Sweet patent, 12 we would still be required to consider whether those claims should be restricted by the doctrine of equivalents. 42 When we make this inquiry, we see that appellants mischaracterize the relation between the DIJIT printer and the Sweet patent: The DIJIT printer does not use the elements disclosed in the Sweet patent in precisely the manner specified in the patent. Rather, the DIJIT printer--to use the time-worn and conclusory formulation of the doctrine of equivalents--uses the elements disclosed in the Sweet patent in a substantially different way to achieve a substantially different result. 43 The Sweet patent does not contemplate a high speed character printer with coordinated multiple jets and a deflection system whereby all charged droplets are deflected into a collector and uncharged droplets are deposited on the recording medium to form the desired characters. The DIJIT printer, quite simply, is a more sophisticated device, embodying inventive insights not part of the Sweet patent. While it does rely on Sweet's fundamental concept of ink jet charging and deflection, it also incorporates those concepts of the Sweet-Cumming patent which Sweet himself described in that later patent as improvements over his original device. Those concepts include the coordination of multiple jets, interception for creating an apparent discontinuity in the image, and a charging and deflection system whereby the final picture is not characteristic of the charging signals. 44 The District Court thus correctly concluded that the Sweet claims must be restricted so as not to read on the DIJIT printer. This interpretation of the claims results from the application of the doctrine of equivalents, not from a mistaken reliance on the illustrative embodiments of the patent, as appellants believe. 45 In reaching this conclusion, we are heavily influenced by the fact that after his initial research, Sweet joined with Cumming to file and obtain a second patent disclosing, in essence, the Mead DIJIT printer. The fact that Sweet filed for a new patent with Cumming represents a contemporaneous implied admission that the Sweet-Cumming complex system of charging an array of jets and using uncharged droplets for writing constitutes a significant advance on Sweet's original work. This is the only reasonable explanation for Sweet's conduct. Appellants cannot deny that a pioneer in the field--Sweet himself--clearly appears to have believed in the early 1960s that the Sweet-Cumming patent--and thus the DIJIT printer--was a significant advance and should be independently patented. Actions sometimes testify more truly about a man's purpose than his words. We are more persuaded by Sweet's conduct at invention time than by his testimony at trial when his interests may have changed because of the way he had sold his patent rights. 46 Although the Sweet-Cumming patent may not represent the basic advance, the quantum leap in insight, represented by the Sweet patent, it is a useful improvement not self-evident from Sweet's first discovery. Sweet should not be relieved of his failure to express this separate advance in his original patent by Judge Hand's misericordiam. The two insights, separately patented, should not be conflated into one, although the first was the more pioneering effort.