Jacob H. Malta and Malmark, Inc. (Mal-mark) (collectively Malta) appeal in this patent case from the November 20,1989 Order of the United States District Court for the Eastern District of Pennsylvania, granting judgment notwithstanding a jury verdict (JNOV) of non-infringement in favor of defendant Schulmerich Carillons, Inc. (Schulmerich). Malta v. Schulmerich Carillons Inc., 13 USPQ2d 1900 (E.D.Pa.1989). Schulmerich cross-appealed from the November 20 Order insofar as it denied Schulmerich’s motion for JNOV that it is the equitable owner of the patent in suit and/or has a shop right under that patent. We affirm on the ground of non-infringement, and do not reach the cross-appeal.
BACKGROUND
A. The Patent in Suit
The patent in suit, U.S. Patent No. 3,941,-082 (’082 patent) issued to Mr. Jacob Malta, is directed to improvements in the design of handbells, of the type used by music groups in churches, schools, and the like. Quoting the patent, “[a] chorus of players using a plurality of tuned bells may render any given tune which falls within the range of notes offered by the specific bells.”
Handbells are generally made up of the bell itself, a handle attached to the closed end of the bell, and a clapper assembly pivotably mounted inside the bell and moving in a single plane. Attached to one end of the clapper assembly is a generally circular clapper or striker which, when the handbell is swung, strikes the bell to ring it.
The ’082 patent discloses a number of improvements in handbell design. Most relevant to this suit is Malta’s provision of a clapper mechanism for allowing the loudness of the bell to be quickly adjusted “on the fly,” i.e., while the bell is being played. Specifically, it was known in the prior art *1322to provide the peripheral surface of the clapper with portions of differing hardness so that, by rotating the clapper, one could change which portion of it struck the bell and consequently the loudness of the bell. However, the clapper could not be adjusted while the bell was being played. The ’082 patent not only provided the clapper with striking surfaces of differing hardness around the periphery thereof, but also provided a detent mechanism which releasably locked the clapper in each desired position. In that way, the clapper could be rotated by hand while the handbell was being played.
The ’082 patent discloses two different embodiments for the clapper. These two embodiments, shown in Figs. 3 and 7 of the ’082 patent, are reproduced below.
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The first embodiment, shown in Fig. 3, has three opposing pairs of “striking surfaces.” The first pair (66) consists simply of the hard rubber of which the clapper is made. The second pair (68) of striking surfaces has a slot cut into the rubber material. The third pair (70) has a piece of soft material such as felt attached to the clapper. These three pairs of striking surfaces provide a loud, medium, and soft sound, respectively.
The second embodiment, shown in Fig. 7, has three “opposed pairs of buttons” (82) attached to the surface of the clapper. Each pair of buttons has a different degree of hardness so that, like the embodiment of Fig. 3, either a soft, medium, or loud sound can be produced, depending on which button pair is aligned to strike the bell. (The patent’s term “opposed pairs” is somewhat confusing. The pairs are not opposed; rather, each pair has opposed buttons of the same hardness.)
Claims 2 and 3 are relevant to this appeal. Claim 3 reads as follows:
3. A handbell comprising in combination: a bell having a generally closed end; a clapper assembly adapted to be removably carried within said bell and centrally of the closed end thereof, said assembly comprising a clapper shaft having one end pivotally associated centrally of the closed end of said bell and carrying a clapper member at its free extremity, said clapper member comprising a generally circular striker assembly rotat-ably positioned substantially normal to said clapper shaft and including a plurality of striking buttons positioned in opposed pairs around the outer periphery thereof and wherein each pair of buttons has a different degree of hardness; means on said clapper assembly coacting with said rotatable striker assembly for permitting rotation of said striker assembly relative to said clapper shaft for selectively positioning desired pairs of buttons in striking relation to said bell; and detent means cooperating with said rotatable striker for releasably holding said striker assembly in any preselected position. [Emphasis ours.]
Claim 2 is very similar to claim 3 and differs primarily in two respects: one, in*1323stead of the “coacting” means recited in claim 3, claim 2 requires an “indexing means” on the handle and the clapper assembly; and, two, instead of the “buttons” recited in claim 3, claim 2 requires “at least three opposed pairs of surface portions wherein each of said pairs has a different degree of hardness.”
B. The Proceedings in the District Court
This case presents the familiar scenario of an employee who leaves his job and starts his own company, only to find himself later at legal odds with his former employer. Jacob Malta was employed by Schulmerich as its chief engineer from 1956 to 1973. In 1973, Mr. Malta left Schulme-rich and, in 1975, formed Malmark. Mal-mark quickly grew and became the primary competitor of Schulmerich in the handbell business. The two companies currently supply about 95% of the handbell market.
In 1985, Malta sued Schulmerich (and other defendants), alleging, among other things, that a line of Schulmerich handbells sold under the trademark “Quick-Adjust” infringes claims 2 and 3 of the ’082 patent.1 The Quick-Adjust handbells are on-the-fly adjustable handbells which have striking surfaces similar to Fig. 3 of the ’082 patent, with pairs of opposed striking surfaces of different hardness by virtue of felt coverings and/or slots or holes formed in the hard rubber clapper.
With respect to claim 3, Schulmerich denied infringement primarily on the ground that its Quick-Adjust handbells do not have a striker assembly with “a plurality of striking buttons positioned in opposed pairs around the outer periphery thereof and wherein each pair of buttons has a different degree of hardness.” Schulmerich argued that the ’082 patent uses the word “buttons” only in conjunction with the embodiment of Fig. 7, and that the Quick-Adjust handbells do not have such buttons. In response, Malta argued, and presented evidence to show, that the word “buttons” was not limited to the embodiment of Fig. 7, but should be construed broadly to literally include striking surfaces such as those of Fig. 3 of the ’082 patent and those of the Quick-Adjust handbells.
In addition to denying liability on the ground of non-infringement, Schulmerich also contended that Jacob Malta had actually invented the subject matter of the ’082 patent while employed at Schulmerich. Consequently Schulmerich argued that it was either the equitable owner of the ’082 patent (due to Mr. Malta’s contractual obligation to assign to Schulmerich all inventions made while working for Schulmerich), or at the very least had a shop right in the patented subject matter.
The case was tried before a jury. Malta requested and obtained a jury instruction not only on literal infringement but also on the doctrine of equivalents. In particular, the judge instructed the jury that
Infringement under the doctrine of equivalents may exist if the accused handbells perform substantially the same function in substantially the same way so as to obtain substantially the same results as the claimed invention.
* * * * # #
In applying the doctrine of equivalents, remember that infringement requires that each and every element of an asserted claim or the equivalent of the element must be present in the accused device.
The jury was given special interrogatories asking whether the Quick-Adjust handbells infringed claims 2 and 3 of the '082 patent, either literally or under the doctrine of equivalents. In response, the jury found, for reasons unrelated to any issue here, that claim 2 was not infringed, but that claim 3, while not literally infringed, was infringed under the doctrine of equivalents. The jury was also given special interrogatories concerning Schulme-rich’s claim of either equitable ownership or shop right, and found that Schulmerich had neither. The jury awarded damages in the amount of $950,000.
*1324Schulmerich moved for JNOY on the grounds that the evidence was not sufficient to support either the finding of infringement under the doctrine of equivalents or the finding that Schulmerich had neither equitable ownership of, nor a shop right in, the ’082 patent.
Approximately seven months later, while decision on the JNOV motion was still pending, this court decided the case of Lear Siegler Inc. v. Sealy Mattress Co., 873 F.2d 1422, 10 USPQ2d 1767 (Fed.Cir.1989). In Lear Siegler, this court reversed a jury’s finding of infringement under the doctrine of equivalents, stating, among other things:
Absent the proper Graver Tank [2] context, i.e., a showing of how plaintiff compares the function, means, and result of its claimed invention with those of the accused device, a jury is more or less put to sea without guiding charts when called upon to determine infringement under the doctrine. While we do not doubt the ability of a jury to decide the factual issue of equivalence, to enable the jury to use its ability, Nestier[3] requires that the three Graver Tank elements [substantial identity of function, way and result] must be presented in the form of particularized testimony and linking argument.
873 F.2d at 1425-26, 10 USPQ2d at 1770. Schulmerich brought Lear Siegler to the judge’s attention in a letter citing the case in support of its motion for JNOY of non-infringement.
The judge upheld the jury’s verdict as to the equitable ownership/shop right question, but agreed that the evidence was insufficient to support the finding of infringement under the doctrine of equivalents. The judge, relying heavily on the Lear Siegler decision, found that Malta had not provided “particularized testimony and linking argument” as to each of the function/way/result prongs of the tripartite Graver Tank equivalency test and granted JNOV in favor of Schulmerich. He set aside the jury verdict and refused to enter a permanent injunction against Schulmerich.
Malta appeals from the grant of JNOV of non-infringement, and Schulmerich cross-appeals from the denial of its JNOV motion based on the equitable ownership/shop right defense.
OPINION
A. Sufficiency of the Motion for Directed Verdict
Before reaching the merits of the infringement question, we address a procedural issue raised by Malta. Malta argues that Schulmerich’s motion for a directed verdict was insufficient to support the JNOV motion that was later granted by the district court.
Rule 50(a) of the Federal Rules of Civil Procedure states that a “motion for directed verdict shall state the specific grounds therefor.” Fed.R.Civ.P. 50(b) allows for entry of JNOV only “in accordance with the party’s motion for a directed verdict.” Orthokinetics Inc. v. Safety Travel Chairs Inc., 806 F.2d 1565, 1579, 1 USPQ2d 1081, 1091 (Fed.Cir.1986) (Ground on which JNOV motion is based must have been asserted in a motion for directed verdict. Issue of willfulness of infringement is not the same thing as issue of infringement).
The record shows that at the close of Malta’s case at the trial in the district court, Schulmerich’s counsel moved orally for directed verdict as follows:
[V]ery briefly we move for a directed verdict on the issue of noninfringement of claims 2 and claims 3 of the 082 patent on the grounds that the evidence is insufficient.
After the close of all the evidence, counsel stated that this motion was renewed.
Malta argues that such general allegations of insufficiency of the evidence are *1325insufficient to support a JNOV motion that was granted because of a lack of particularized function/way/result testimony and linking argument. We disagree. As is clear from the infringement discussion in section B, infra, the district court correctly granted Schulmerich’s motion for JNOV because Malta failed to present sufficient evidence to the individual function/way/result elements of the Graver Tank equivalency test. That is to say, the evidence of infringement of claim 3 was insufficient, which was the basis of the motion for directed verdict.
The trial judge’s initial order filed Nov. 21, 1989, began by stating “Because the evidence does not prove the essential elements of plaintiffs’ case, the [defendants’] motion for judgment n.o.v. must be granted.” The next day the judge signed another order supplementing the first order saying it “is reopened and judgment is hereby entered for defendant as if the verdict requested at the close of the evidence had been directed. Fed.R.Civ.P. 50(b).”
Clearly the trial judge had no doubt, nor do we, that the ground stated in support of the first motion for directed verdict and in support of the motion for JNOV were one and the same. The latter therefore was supported as required by Fed.R.Civ.P. 50(a) and (b). Malta’s argument to the contrary is without merit.
B. Infringement and the Doctrine of Equivalents
To convince this court that a trial judge erred in granting a motion for JNOV, an appellant must show that there was substantial evidence to support the jury’s factual findings, and that those findings can support the jury’s legal conclusion. Orthokinetics, 806 F.2d at 1571, 1 USPQ2d at 1085.
. In order to prove infringement under the doctrine of equivalents, a patentee must show that the accused device performs substantially the same function in substantially the same way to achieve substantially the same result as the claimed device. Graver Tank, 339 U.S. at 608, 70 S.Ct. at 856, (85 USPQ at 330). The “substantially the same way” prong of this test may be met if an equivalent of a recited limitation has been substituted in the accused device. See Corning Glass Works v. Sumitomo Elec. U.S.A. Inc., 868 F.2d 1251, 1259, 9 USPQ2d 1962, 1967 (Fed.Cir.1989). The issues of infringement and of equivalency are issues of fact. Sun Studs Inc. v. ATA Equip. Leasing Inc., 872 F.2d 978, 986, 10 USPQ2d 1338, 1345 (Fed.Cir.1989).
As an initial matter, Malta contends that the trial judge erred in his grant of JNOV when he stated that a patentee
must substantiate all three aspects of equivalency, per Graver Tank, as to each limitation of a claim in order to establish equivalence between claim and accused device.
This court has never adopted the three prong approach to determining equivalency of a limitation. In Pennwalt Corp. v. Durand-Wayland Inc., 833 F.2d 931, 4 USPQ2d 1737 (Fed.Cir.1987) (in banc), cert. denied, 485 U.S. 961, 108 S.Ct. 1226, 99 L.Ed.2d 426 (1988), this court upheld a finding of no infringement involving the doctrine of equivalents because the patentee did not establish the presence, in the accused device, of every claim element4 “or its substantial equivalent.” Pennwalt, 833 F.2d at 935-36, 4 USPQ2d at 1740-41 (claimed function found missing). Penn-walt did not set forth a test as to how one proves that an element in an accused device is the “substantial equivalent” of a claim limitation directed to a single element in dispute — here the “buttons.”
In the subsequent Corning Glass case, 868 F.2d at 1260, 9 USPQ2d at 1968-69, we stated
This court has not set out in its precedent a definitive formula for determining equivalency between a required limitation or combination of limitations and what has been allegedly substituted therefor in the accused device. Nor do *1326we propose to adopt one here. We note that the district court resolved the question by comparison of the function/way/result of the substitution with the function/way/result of the limitation in the context of the invention; that is, the court made a subsidiary analysis comparable to the overall function/way/result analysis mandated for determining infringement under the doctrine of equivalents.
* * * * * *
The district court’s “function/way/result” equivalency analysis with respect to a claim limitation appears to be a helpful way to approach the problem and entirely in accord with the analysis actually made in Graver Tank....
Thus, while comparison of function/way/result is an acceptable way of showing that structure in an accused device is the “substantial equivalent” of a claim limitation, it is not the only way to do so, and to this extent, the trial judge in the present case did err. However, this error is harmless.
How equivalency to a required limitation is met necessarily varies from case to case due to many variables such as the form of the claim, the nature of the invention defined by it, the kind of limitation that is not literally met, etc. For example, the fact situations in Coming Glass and in this case are simply not comparable, yet application of the doctrine must be adapted to each, which is why the Coming panel declined to propose a formula of general applicability for determining equivalency to a claim limitation. See Hughes Aircraft Co. v. United States, 717 F.2d 1351, 1361, 219 USPQ 473, 480 (Fed.Cir.1983) (“The doctrine is judicially devised to do equity”).
Malta’s proofs lack evidence to prove either that all three prongs of the Graver Tank test are met or that the “buttons” limitation was met equivalently. The evidence Malta principally points to is the following two portions of the testimony of Jacob Malta (emphasis ours):
Q: Would you make that clear as to what the structure is in the Schulmerich bell that corresponds to the buttons that are recited in the claim?
A: All right. The structure is these portions of the clapper, in this case the opposed felt pieces, and adjacent thereto on each side these elliptical spots of green, indicating that there are additional pairs of opposed striking surfaces.
Q: Striking surfaces. Would you go on with your explanation of how the portion illustrated in color in the exhibit corresponds to the claim language?
A: Right. The — as I described, we have a plurality of buttons, there’s three sets, buttons or the equivalent thereof, and they are in opposed pairs around the periphery. We’ve described how they are related to these indexing slots in the underside of the brass clapper insert, and each pair has a different degree of hardness, we’ve described that. Here again we have felt which produces a soft impact sound. Here, this would be in relation to this slotted portion here where we have a slot in the core and at 180 degrees another slot, that would be the medium impact position. And then the lowermost one would be the — this one opposed to this where we have a solid plastic material in the impact plane producing a brilliant sound,
and:
Q: And Claim 3 includes as a part of the striker assembly the phrase, “A plurality of striking buttons positioned in opposed pairs around the outer periphery thereof wherein each pair of buttons is a different degree of hardness,” correct?
A: That’s right.
Q: Do you find those buttons in [the accused] structure?
A: Yes, there are buttons per se here, the felt, the opposed felt certainly are visible buttons. The opposed locations or surfaces which are related to these long slots are likewise buttons and the opposed pair of solid portions again are buttons.
Q: Do you mean they’re buttons or function like buttons?
A: They function like buttons....
*1327This court in Lear Siegler, following Nestier, held that a patentee must prove substantial identity as to each of the function, way, and result prongs of the doctrine of equivalents. Lear Siegler, 873 F.2d at 1425, 10 USPQ2d at 1770, Nestier, 739 F.2d at 1579-80, 222 USPQ at 750. As the court noted in Lear Siegler, such proof is necessary to prevent the jury from being “put to sea without guiding charts,” and from determining infringement by simply comparing the claimed invention and the accused device “as to overall similarity.” Lear Siegler, 873 F.2d at 1426-27, 10 USPQ2d at 1770-71.5
With this requirement in mind, we agree with the district court that the evidence was insufficient to support a finding of infringement under the doctrine of equivalents. Malta’s brief to this court discusses the above testimony at great length, explaining how this testimony informs the jury of the function, way, and result achieved by the accused device. However, what is clearly lacking in that testimony is a sufficient explanation of both why the overall function, way, and result of the accused device are substantially the same as those of the claimed device and why the plastic/slotted plastic/felt arrangement is the equivalent of the claimed buttons limitation. Mr. Malta’s offhand and conclusory statements (“buttons or the equivalent thereof” and “They function like buttons”) are not sufficiently particularized evidence. In short, with little guidance, the jury was left to its own imagination on the technical issue of equivalency.
There is no other evidence in the case which provides the necessary “substantial evidence” on the issue of infringement under the doctrine of equivalents. The ’082 patent itself has the following to say about the two embodiments of Figs. 3 and 7 (Col. 4, 11. 46-48):
Another form of clapper is depicted in Fig. 7. It has all of the advantages of the one shown in Fig. 3 but varies in design, flexibility and simplicity.
Thus, while the two embodiments are described as being alternatives to each other, they are not equivalent in “way”. Further, the patent specifically uses the term “striking surfaces” with respect to the embodiment of Fig. 3, but uses the different term “buttons” with respect to Fig. 7. The claims of the patent maintain this distinction; claim 2 describes the surface of the clapper using the broad term “surface portions,” while claim 3 uses the narrower term “buttons.” Though application of the doctrine of equivalents extends the protection of the patent beyond the literal words of the claims, it is not proper “to erase a plethora of meaningful structural and functional limitations of the claim on which the public is entitled to rely in avoiding infringement.” Perkin-Elmer Corp. v. Westinghouse Elec. Corp., 822 F.2d 1528, 1532, 3 USPQ2d 1321, 1324 (Fed.Cir.1987). In the present case, where Malta employs a broad term in one claim, but a narrower term, used with respect to only one embodiment in the specification, in another claim, the implication is that infringement of the second claim can be avoided by not meeting the narrower term.
In sum, we agree with the district court that Malta failed to present evidence sufficient to support a finding of infringement of claim 3 under the doctrine of equivalents, and we therefore uphold the court’s grant of JNOV.
C. “Retroactive Application of Lear Siegler”
Malta argues that it is improper to retroactively apply the holding of Lear Sie*1328gler to this case, citing Chevron Oil Co. v. Huson, 404 U.S. 97, 92 S.Ct. 349, 30 L.Ed.2d 296 (1971), since Lear Siegler allegedly established a new principle of law. However, as noted in the previous two sections, Lear Siegler merely requires that a patentee prove all elements of his case, which, with respect to the doctrine of equivalents, means that a patentee must prove that each prong of the Graver Tank equivalency test is met. While Lear Sie-gler set forth this requirement in language particularly suitable to the present jury case, we do not agree that Lear Siegler established any new principle of law. Reading the opinion is enough to show that the district court was right in saying (n. 7): “Lear Siegler merely repeats in so many words the explication of Nestier." Nestier was decided in 1984. This case was not tried until 1988. There has been no retroactive application of law.
D. Schulmerich’s Cross-Appeal
Having upheld the district court’s determination of non-infringement, we need not and do not reach the issues of equitable ownership and shop right raised in Schulmerich’s cross-appeal. Schulmerich’s brief states:
If this Court affirms the trial court in relation to the grant of JNOY due to the failure of proof at trial by Malta/Mal-mark, it need not consider Schulmerich’s cross-appeal on the issue of co-ownership.
E. The Dissent
With all respect to the dissent, we are not rejecting a jury verdict or making a de novo determination of infringement. We are reviewing the district court’s judgment notwithstanding the jury verdict, the district court which tried the case, heard all the evidence including Mr. Malta’s self-serving testimony and opinions about claim construction together with his elaborate illustrations so laboriously listed in the dissent. What we are affirming is the judgment of the fully informed district judge based on his holding that the evidence was insufficient to support a finding of infringement under the doctrine of equivalents, a doctrine the application of which enlarges the coverage of the patent beyond what is defined in the claims. We are following the instruction of the Supreme Court in Graver Tank, 339 U.S. at 610, 70 S.Ct. at 857, referring to the application of the doctrine, that:
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.
In essence, what we are affirming is the district court’s decision that, in view of all the evidence, this is not a case in which the doctrine of equivalents can be applied, that being the only basis on which Malta can contend that his patent is infringed. The district court’s detailed opinion of November 21, 1989, discussed the doctrine of equivalents and its proper application at great length and came to the correct conclusion that “Plaintiffs offered no more than brief, conclusory evidence that the Schulmerich bell contains the equivalent of the disputed buttons.” That is what we are reviewing, not the jury verdict, and we will not disturb it. For this court’s most recent views on application of the doctrine of equivalents, see London v. Carson Pirie Scott & Co., 946 F.2d 1534, 20 USPQ2d 1456 (Fed.Cir.1991).
CONCLUSION
For all of the above reasons, the judgment of the district court is affirmed.
AFFIRMED.
. The complaint also included claims other than patent infringement against Schulmerich and other named defendants, Ronald O. Beach, Kelly-Michener, Inc., and The Handchime Co. The case was subsequently bifurcated into patent and non-patent portions.
. Graver Tank and Mfg. Co. v. Linde Air Products Co., 339 U.S. 605, 70 S.Ct. 854, 94 L.Ed. 1097 (85 USPQ 328) (1950).
. Nestier Corp. v. Menasha Corp.-Lewisystems Div., 739 F.2d 1576, 222 USPQ 747 (Fed.Cir.1984), cert. denied, 470 U.S. 1053, 105 S.Ct. 1756, 84 L.Ed.2d 819 (1985).
. In this context, the word "element” refers to a limitation of the claim, and not necessarily to a component of the claimed device. See Corning Glass, 868 F.2d at 1259, 9 USPQ2d at 1968.
. The dissent has attempted to draw out the function, way, and result achieved by the accused and claimed devices from the testimony quoted in the dissenting opinion. However, its conclusion as to what those functions, ways, and results are does not come from the testimony itself but from Malta’s appeal brief and from its own conjecture. While Lear Siegler does not go so far as to require recitation of the magic words “function”, "way”, and “result”, we think that it at least requires the evidence to establish what the function, way, and result of both the claimed device and the accused device are, and why those functions, ways, and results are substantially the same.