United States Court of Appeals for the Federal Circuit
October 29, 1999
ESSILOR INTERNATIONAL, PLAINTIFF-APPELLANT,
NIDEK CO., LTD. AND SANTINELLI INTERNATIONAL, INC., DEFENDANTS-CROSS APPELLANTS.
Before Mayer, Chief Judge, Rich, *fn1 Circuit Judge, and Smith, Senior
The opinion of the court was delivered by: Per Curiam.
Essilor International (Essilor) appeals the judgment of the United States District Court for the Eastern District of New York, No. 95-CV-1243, of non-infringement of United States Patent No. 4,596,091 (the '091 patent) which is directed to a machine for automatically grinding a bevel on the edge of an eyeglass lens. Nidek Co., Ltd. (Nidek) and Santinelli International, Inc. (Santinelli) cross-appeal the court's judgment that the '091 patent is not invalid, that Essilor did not engage in unfair competition, and that laches and equitable estoppel do not apply. We affirm the district court's judgment in all respects.
We begin with infringement. Step (f) of claim 1, the only independent claim at issue, requires the claimed invention to have (emphasis added):
a control means including
means for storing a collection of predetermined bevelling or grooving paths and
means for comparing first and second reference paths with the collection of predetermined paths and for selecting one of the bevelling or grooving paths which is intermediate the first and second reference paths from the collection of predetermined paths whereby said control means controls the displacement of said lens in accordance with the selected intermediate path to form the edge of the lens. '901 patent, col. 10, ln. 67 to col. 11 ln. 8.
The district court found that the accused devices did not satisfy the three means limitations relating to the predetermined bevelling or grooving paths, namely the means for storing, means for comparing, and means for selecting limitations. In reaching this Conclusion, the court construed a predetermined bevelling and grooving path as meaning an actual beveling path that has already been stored in the control unit and not covering pre-stored equations that are used to calculate the beveling path, such as the equations used in the accused devices. Essilor argues that the district court erred in its claim construction and that under a proper construction, a predetermined beveling path would include the equations that are stored in the control unit of the accused devices and that the accused devices literally infringe the claim.
Claim construction is a question of law which we review de novo. See Cybor Corp. v. FAS Techs., Inc., 138 F.3d 1448, 1455-56, 46 USPQ2d 1169, 1173-74 (Fed. Cir. 1998) (en banc). We agree with the district court's claim construction. Contrary to Essilor's assertions, the plain meaning of a predetermined bevelling path is a beveling path that has been set previously. A bevelling path represented by an equation which needs the input of additional information before the path can be determined, such as the equations used in the Nidek devices, is not a predetermined bevelling path.
Essilor argues that to those skilled in the art, a typical bevelling path can be described by equations such as ratios or by diopter values for the spheres on which the paths lie. We disagree. As the district court found, ratios and diopters are not the only parameters used to calculate a bevelling path. Additional information is needed before the beveling path can be determined.
There is nothing in the written description or prosecution history that changes the plain meaning of the term. The passage in the written description that states that the control unit is arranged so that the path can be reconstructed for the point of contact of the lens with the bevelling wheel does not support Essilor's argument that reconstruction of a path necessarily implies the use of equations that require additional data to calculate a bevelling path. Essilor does not argue that the accused devices infringe under the district court's claim construction. Therefore, we affirm the district court's finding of no literal infringement.
Essilor also contends that even if the district court's claim construction is correct, it erred in finding that Nidek's devices do not infringe under the doctrine of equivalents. Essilor asserts that the district court should have analyzed whether the equations used by the Nidek devices are equivalent to the predetermined beveling paths required by the claims.
To infringe under the doctrine of equivalents, an accused device must meet every limitation of the claim either exactly or by a substantial equivalent. See Warner-Jenkinson Co. v. Hilton Davis Chem. Co., 520 U.S. 17, 29 (1997). One test used to determine if the accused device is a substantial equivalent is to ask whether the element performs substantially the same function in substantially the same way to obtain substantially the same result as the claim limitation. See Graver Tank & Mfg. Co. v. Linde Air Prods. Co., 339 U.S. 605, 608 (1950). Equivalence is a question of fact, which we review under the clearly erroneous standard. See id. at 609-10.
Even if we agree with Essilor's argument that in some instances an equation may be the equivalent of a predetermined beveling path, we cannot say that the district court erred when it found that in this case, the accused devices do not perform the comparing and selecting functions required by the claim in the same way. Specifically, the district court found that the accused devices do not perform an equivalent of the "means for comparing" and the "means for selecting" limitations because the accused devices operate in a different way.
The comparing function requires the control means to compare the first and second reference paths with the collection of predetermined paths. Essilor contends that the Nidek devices perform this function when the control unit in the accused devices asks "is the minimum lens thickness 1.5 mm?" The district court found that although the accused devices do compare information from the lens to data stored in the computer such as ratios and diopters, the comparison performed by the accused devices is not equivalent to the comparison required by the claims. We cannot say the district court erred in its determination that the accused devices do not perform the comparing function in the same way.
The selecting function requires the control unit to select a beveling path which is intermediate of the first and second reference paths from the collection of predetermined reference paths. Essilor asserts that the Nidek devices perform the selecting function when the control unit selects whether the bevel will be placed either 40% back from the front of the lens or 30% back from the front of the lens and then shifted by a fraction of a millimeter, based on whether the minimum thickness of the lens is greater than or less than 1.5 mm. The district court found that the accused devices select routes which will ultimately lead to a bevelling path, but the selection of routes is not the selection of the actual bevelling path. Again, we cannot say that the district court clearly erred in concluding that the accused devices do not perform the selecting function in substantially the same way.
On cross appeal, Nidek and Santinelli assert that the '091 patent is invalid as not enabled, for failing to disclose the best mode, and because it does not disclose a structure corresponding to the control means limitation. They also assert that laches and equitable estoppel preclude Essilor's infringement action and that Essilor is guilty of unfair competition. We address each of these issues in turn.
Nidek and Santinelli contend that the '091 patent is invalid for lack of enablement under the first paragraph of 35 U.S.C. § 112 (1994) because the patent does not describe the paths that are within the collection of predetermined paths and because the patent does not describe how to perform the comparing and selecting functions. To satisfy the enablement requirement, the disclosure must be sufficient to enable one skilled in the art to practice the claimed invention without undue experimentation. See Northern Telecom, Inc. v. Datapoint Corp., 908 F.2d 931, 941, 15 USPQ2d 1321, 1329 (Fed. Cir. 1990). Although enablement is a question of law, which this court reviews de novo, we review the factual findings underlying the legal Conclusion for clear error. See In re Vaeck, 947 F.2d 488, 495, 20 USPQ2d 1438, 1444 (Fed. Cir. 1991).
The district court found that the predetermined bevelling paths were based on the bevelling paths of the prior art mechanical cams which were known to one of ordinary skill in the art. The district court also found that at the time of the invention, control units were easily purchased off-the-shelf items and that the means for comparing and selecting could be readily accomplished by writing suitable software to perform the relatively common calculations.
The cross appellant's evidence to support their argument that one of ordinary skill would not be able to determine the "predetermined bevelling paths" includes an assertion that Essilor was not able to construct a lens edger using the patent specifications and that the software would need to be developed by someone knowledgeable about lens edgers. This evidence has not convinced us that the district court clearly erred. The district court heard contrary evidence establishing that Essilor was able to develop a lens edger in a reasonable amount of time and that it was within the skill in the art to program a control unit to perform the claimed storing, comparing and selecting functions. We must honor the district court's assessment of this evidence. See Hybritech Inc. v. Monoclonal Antibodies, Inc., 802 F.2d 1367, 1375, 231 USPQ 81, 87 (Fed. Cir. 1986) (Where there are two permissible views of the evidence, the fact finder's choice between them cannot be clearly erroneous.). Consequently, the district court's factual Conclusions regarding enablement of the '091 patent are not clearly erroneous. Furthermore, the court's ultimate Conclusion of enablement rested on a correct interpretation and application of legal principles. Therefore, we affirm the decision that the '091 patent contains an enabling disclosure.
Nidek and Santinelli also appeal the district court's judgment that the '091 patent satisfied the best mode requirement under 35 U.S.C. § 112. Nidek asserts that the patent failed to disclose that the "predetermined bevelling paths" were based on the prior physical cams used in the trade.
Failure to comply with the best mode requirement amounts to concealing the preferred mode contemplated by the applicant at the time of filing the application. See Applied Med. Resources Corp. v. United States Surgical Corp., 147 F.3d 1374, 1377, 47 USPQ2d 1289, 1291 (Fed. Cir. 1998). Whether a best mode disclosure is adequate, that is, whether the inventor concealed a better mode than was disclosed, is a function of not only what the inventor knew, but also how one skilled in the art would have understood the disclosure. See id. Determination of whether the best mode requirement has been met is a question of fact, which this court reviews for clear error. See id.
Here, the district court found that the patent taught that "typical paths" constituted the preferred mode and that one of ordinary skill in the art would have understood typical paths to include the prior art physical cams. Thus, the district court concluded that the inventors disclosed the best mode of practicing the invention that they contemplated. We cannot say that the district court clearly erred in its determination.
Nidek and Santinelli also contend that the district court erred in holding that intentional concealment was necessary for there to be failure to meet the best mode requirement. We do not read the district court opinion as requiring intentional concealment and thus this argument must also fail.
Nidek and Santinelli contend that the '091 patent is invalid for failing to particularly point out and distinctly claim the invention because the patent fails to adequately disclose a structure corresponding to the means-plus-function language. We disagree.
Patentees may express claim elements in "means-plus-function" format. See 35 U.S.C. § 112, ¶ 6. In a means-plus-function claim, the claim element is expressed as a means for performing a specified function and the claim is construed as covering the corresponding structure described in the specification and equivalents thereof. See id. 35 U.S.C. § 112, ¶ 2 requires that all claims, including means-plus-function claims, particularly point out and distinctly claim the subject matter which the applicant regards as his invention. For a means-plus-function claim to satisfy the section 112, ¶ 2 requirement, the specification must adequately describe the structure which performs the specified function. See In re Donaldson, 16 F.3d 1189, 1195, 29 USPQ2d 1845, 1850 (Fed. Cir. 1994) (en banc).
The specification does not have to describe the structure corresponding to a means-plus-function limitation in explicit detail. For example, in In re Dossel, 115 F.3d 942, 946-47, 42 USPQ2d 1881, 1885 (Fed. Cir. 1997), we held that the specification adequately described the structure corresponding to the means for reconstructing data when it recited a device that receives digital data from memory and from a user. The fact that the specification did not recite the term "computer" nor quote computer code that may be used in the invention, did not render the means clause invalid under section 112, ¶ 2.
In our case, the patent discloses a "control unit" as the structure that performs the function of storing, comparing and selecting the bevel path. '091 pat. col. 8, ll. 7-23. The patent further states that the control unit is composed of a central storage and computation unit and that the construction of a control unit is within the capabilities of a person skilled in the art. '091 pat. col. 8. ll. 24-33. The district court found that it would have been clear to one of ordinary skill what structure must perform the function recited in the means-plus-function limitation. The district court found that the necessary elements of the control unit which would perform these functions were described in the patent and that the functions described in the specification could be accomplished using computer programs. We agree with the district court.
Nidek and Santinelli contend that the district court erred in finding that laches and equitable estoppel did not bar Essilor's infringement suit. The standard of review for both laches and equitable estoppel is abuse of discretion. See A.C. Aukerman Co. v. R.L. Chaides Constr. Co., 960 F.2d 1020, 1028, 22 USPQ2d 1321, 1325 (Fed. Cir. 1992) (en banc).
The district court found that the four year delay in bring suit was reasonable as Essilor and Nidek were attempting to negotiate a solution to avoid litigation over the United States patent and that neither Nidek nor Santinelli suffered material prejudice as a result of the delay in bringing suit. See Wanlass v. General Elec. Co., 148 F.3d 1334, 1337 (Fed. Cir. 1998) (setting forth the necessary elements for laches); see also Aukerman, 960 F.2d at 1028, 22 USPQ2d at 1324-25 (setting forth the necessary elements for laches and equitable estoppel). There was sufficient evidence in the record to support the district court's findings and the cross appellants have not convinced us that the district court abused its discretion in declining to find laches or equitable estoppel.
We also reject cross appellants' argument that the district court abused its discretion in dismissing their unfair competition claim. There is sufficient evidence in the record to indicate that the law suit was a good faith attempt by Essilor to enforce its patent rights. The mere fact that Essilor instituted the law suit on the eve of a trade show and informed a trade publication about the suit does not render the suit an act of unfair competition.