Full opinion text
FINDINGS OF FACT AND CONCLUSIONS OF LAW FORESTER, District Judge. I.INTRODUCTION This action was tried before the Court, beginning on February 4, 1997, and concluding on February 10, 1997. This matter is now before the Court for entry of Findings of Fact and Conclusions of Law. Having considered the evidence introduced at trial, the parties’ Proposed Findings of Fact and Conclusions of Law and objections thereto, and the applicable law, the Court hereby makes the following Findings of Fact and Conclusions of Law. II.FACTS 1. Plaintiff, Mas-Hamilton Group (“Mas-Hamilton”), is a Kentucky corporation having its principal place of business in Lexington, Kentucky. The principal shareholders of Mas-Hamilton are J.D. Hamilton (President) and his father, Jimmy Hamilton (Chairman). Mas-Hamilton is in the business of designing, manufacturing and selling high security electronic locks and related products. 2. Defendant, LaGard, Inc. (“LaGard”) is a California corporation having its principal place of business in Torrance, California. The company is owned primarily by Klaus (“Nick”) Gartner (CEO and Chairman), and Peter Phillips (now a consultant to LaGard). Mr. Gartner is a citizen of Germany and Mr. Phillips is a citizen of Great Britain. The president of LaGard is Larry Cutter. 3. LaGard is the owner of U.S. Patent No. 5,307,656 entitled “High Security Electronic Dial Combination Lock” (the “’656 patent”), which issued on May 3, 1994. The patent names as inventors Mr. Gartner, Mr. Cutter and Mr. Phillips. Gartner, Phillips, and Cutter applied for the patent on December 17,1990. 4. On August 4, 1994, LaGard charged Mas-Hamilton’s electronic high security lock with infringement of the ’656 patent. PX71. At that time, the only lock sold by Mas-Hamilton was the X-07 lock. The X-07 lock (PX 124) is the only product manufactured or sold by Mas-Hamilton considered by the Court in connection with the infringement charges in this action. 5. In response to that infringement charge, Mas-Hamilton initiated the present action on September 8, 1994, seeking a declaratory judgment that it did not infringe the ’656 patent. After an unsuccessful attempt to dismiss the case on jurisdictional grounds, LaGard counterclaimed for infringement of the ’656 patent on July 18, 1995. In reply to the counterclaim, Mas-Hamilton asserted that the ’656 patent was invalid and not infringed. III.PATENT VALIDITY 6. A patent issued by the Patent Office is presumed to be valid as to each claim independently of the other claims. 35 U.S.C. § 282; Jones v. Hardy, 727 F.2d 1524, 1528 (Fed.Cir.1984). In order to rebut this presumption, an accused infringer must establish by clear and convincing evidence the invalidity of each claim asserted to be invalid. Blonder-Tongue Laboratories v. University of Illinois Foundation, 402 U.S. 313, 335, 91 S.Ct. 1434, 28 L.Ed.2d 788 (1971); Shelcore, Inc. v. Durham Industries, Inc., 745 F.2d 621, 625 (Fed.Cir.1984). 7. It is also presumed that a Government agency, such as the United States Patent and Trademark Office, has properly done its job in examining a patent. American Hoist & Derrick Co. v. Sowa & Sons, Inc., 725 F.2d 1350, 1359 (Fed.Cir.1984). 8. LaGard’s patent covers an electronic combination lock. While the lock is a good design, inventor Nick Gartner testified at trial that he did not think anything in the lock industry is breakthrough. (Gartner, Trial Transcript Vol. Ill, afternoon session, p. 70). 9. In mechanical combination locks that existed before electronic locks, rotating the combination dial rotates a series of tumbler wheels and a cam wheel. The dial’s back and forth rotation aligns gates or notches on the tumbler wheels. When the user dials the combination properly, all the gates align, which allows a fence to drop into the gates. When the fence drops into the gates, it allows a lever to move toward the cam wheel. The other end of the lever mounts on a withdrawal bolt. When the lever moves toward the cam wheel, a nose at the end of the lever drops into a curved indentation on the cam wheel. Because the shape of the indentation conforms to the nose’s shape, the cam wheel holds the lever as the cam wheel rotates. Continued rotation of the cam wheel pulls the lever to the left, which, in turn, withdraws the bolt to allow a safe door to open. 10. Mechanical parts in this type of lock regularly move against each other. For example, the fence and the lever slide along the outside of the tumbler wheels and the cam wheel as one dials the combination. Experts including thieves and spies can listen or feel (or with X-rays see) when the fence and gates line up. With this information, they could defeat the lock. 11. In prior art electronic combination locks, dial rotation generates electronic signals. The signals activate an electric device, such as a solenoid, to release the lever so that the lever can engage the cam wheel. As with mechanical locks, continued rotation of the cam wheel pulls the lever to withdraw the bolt. 12. The invention described and claimed in LaGard’s ’656 patent combines several important features, which include: a.The cam wheel turns freely without the bolt-pulling lever contacting the cam wheel until the user enters the proper combination. b. The lever is secured away from the cam wheel until the user enters the proper combination. c. Upon entering the proper combination, an internal mechanism positively drives the lever toward the cam wheel. d. The internal mechanism includes an electro-mechanical driver such as a linear or rotating solenoid. e. To reduce power needs, that solenoid only causes part of the mechanism to engage the cam wheel. Continued manual rotation of the cam wheel instead of electrical force from the solenoid continues to drive the mechanism, which pulls the lever into the cam wheel. 13. Plaintiff Mas-Hamilton has challenged validity on the following grounds: a. Incorrect inventorship. b. Prior invention by another under 35 U.S.C. § 102(g). c. Derivation under 35 U.S.C. § 102(f). d. The invention was “on sale” more than one year prior to the date of the application for patent under 35 U.S.C. § 102(b). e. The invention was in public use more than one year prior to the date of application for patent under 35 U.S.C. § 102(b). f. Failure to meet the best mode requirement under 35 U.S.C. § 112. g. Lack of enablement under 35 U.S.C. § 112. h. Vague or indefinite claims under 35 U.S.C. § 112. i. Anticipation/obviousness under 35 U.S.C. §§ 102 and 103. A. INCORRECT INVENTORSHIP 14. A person is entitled to a patent unless he did not himself invent the subject matter sought to be patented. 35 U.S.C. § 102(f); New England Braiding Co. v. A.W. Chesterton Co., 970 F.2d 878, 883 (Fed.Cir.1992). A patent applicant must also submit an oath “that he believes himself to be the original and first inventor of the ... machine .. for which he solicits a patent”. 35 U.S.C. § 115; Glaxo, Inc. v. Novopharm, Ltd., 52 F.3d 1043, 1051 (Fed.Cir.1995). 15. The inclusion of fewer or more than the true inventors in a patent renders it void. Jamesbury Corp. v. United States, 207 Ct.Cl. 516, 518 F.2d 1384, 1395 (1975); Iowa State Univ. Research Foundation, Inc. v. Sperry Rand Corp., 444 F.2d 406, 408 (4th Cir.1971). Misjoinder of inventors thus renders the patent invalid under 35 U.S.C. § 102(f). O.M.S. Inc. v. Dormont Manufacturing, Co., 39 U.S.P.Q.2d 1151, 1154 (W.D.Pa.1996). Such a patent with inventor-ship defects is unenforceable until corrective steps are taken. Merry Mfg. Co. v. Burns Tool Co., 335 F.2d 239, 242 (5th Cir.1964). 16. A patent invalid for improper inven-torship may be corrected by the Patent Office or a court: Whenever through error a person is named in an issued patent as the inventor ... and such error arose without any deceptive intention on his part, the Commissioner [of Patents] may ... with proof of the facts and such other requirements as may be imposed, issue a certificate correcting such error. The error of omitting inventors or naming persons who are not inventors shall not invalidate the patent in which such error occurred if it can be corrected as provided in this section. The court before which such matter is called in question may order correction of the patent on notice and hearing of all parties concerned, and the Commissioner shall issue a certificate accordingly. 35 U.S.C. § 256. 17. The parties disagree as to which side has the burden of proof on the issue of deceptive intent. Defendant contends that in order to invalidate a patent for misjoinder of inventors, Plaintiff must show deceptive intent by clear and convincing evidence. Plaintiff, however, contends that once a patent challenger shows that a co-inventor has been improperly joined in a patent, the burden shifts to the patent owner to prove that the inventors were improperly named without deceptive intent. 18.Mas-Hamilton asserts that the ’656 patent is invalid for incorrect inventorship because it incorrectly named Larry Cutter as an inventor. Furthermore, the patent application incorrectly stated that Nick Gartner and Peter Phillips were American citizens. 19. The ’656 patent incorrectly names Mr. Cutter as a joint inventor with Mr. Gartner and Mr. Phillips. Cutter’s contribution to the lock design came after Gartner and Phillips reduced the invention to practice. Mr. Gartner took a redueed-topractice prototype to Mosler in November 1989, but Cutter did not become a LaGard employee until January 1990. Cutter made suggestions for prototypes for LaGard to submit to Mosler later in 1990. Gartner incorrectly considered that those activities made Cutter a joint inventor. 20. On September 30, 1996, LaGard filed a petition to correct inventorship with the Patent Office. LaGard’s petition complied with the Patent Office’s requirement set forth in 37 C.F.R. § 1.48(a)(1) inasmuch as it contained “a statement of facts verified by the original named inventor or inventors.” Inventors Gartner and Phillips and mistaken inventor Cutter submitted declarations with the petition showing that through error Cutter is named in the ’656 patent as the inventor, and that the error arose without any deceptive intention on his part. 21. LaGard’s petition to correct inventor-ship also informed the Patent Office about the errors in Gartner’s and Phillips’ citizenship. 22. On February 3, 1997, the Patent Office granted LaGard’s petition to correct in-ventorship, finding that the mistake in in-ventorship resulted from error without any deceptive intent. DX 115. 23. Regardless of which side has the burden of proof on the issue of deceptive intent, the Court is satisfied from the testimony and evidence presented at trial that the errors in citizenship on the patent application and the incorrect naming of Cutter as an inventor were the result of inadvertence, and were not errors made with deceptive intent. 24. The Court thus finds that the ’656 patent is not invalid due to incorrect inven-torship. B. INVENTION BY ANOTHER 25. A person has no right to a patent for something which was invented by someone else. In Re Bergy, 596 F.2d 952, 960 (C.C.P.A.1979). A patent is invalid if its subject matter was first invented by another. 26. 35 U.S.C. § 102(g) provides: A person shall be entitled to a patent unless-— (g) before the applicant’s invention thereof the invention was made in this country by another who had not abandoned, suppressed or concealed it. In determining priority of invention, there shall be considered not only the respective dates of conception and reduction to practice of the invention, but also the reasonable diligence of one who was first to conceive and last to reduce to practice, from a time prior to conception by the other. 27. Priority of invention goes to the first party to reduce an invention to practice unless the other party can show that it was the first to conceive the invention and that it exercised reasonable diligence in later reducing that invention to practice. Mahurkar v.. C.R. Bard, Inc., 79 F.3d 1572, 1577 (Fed.Cir.1996), quoting Price v. Symsek, 988 F.2d 1187, 1190 (Fed.Cir.1993). The term “conception” means the complete performance of the mental part of the inventive act. Reduction to practice occurs when the invention works for its intended purpose. 28. For its prior invention defense, Mas-Hamilton asserts that Clayton Miller and Michael Harvey invented the X-07 lock before LaGard’s inventors invented the lock described and claimed in the ’656 patent. 29.Nick Gartner and Peter Phillips have been involved in the lock industry for many years. Each is at least one named inventor of thirty or more patents relating to locking mechanisms. Gartner’s and Phillips’ patents have been licensed to many lock manufacturers and distributors, including Miller. Gart-ner received commendations from the Navy Department and the FBI for his work in developing a lock for use aboard Trident submarines to protect against a “knowledgeable psychotic.” 30. In November 1989, George Herrmann and Gartner took a working prototype lock to Mosler, Inc., in Hamilton, Ohio. Mr. Herr-mann is now and in 1989 was an independent sales representative selling LaGard products. There, Herrmann and Gartner showed the lock to Mosler engineers in order to interest Mosler in manufacturing the lock under license. 31. The lock that LaGard took to Mosler did not have a combination. Instead, closing a switch sent an electronic signal to the solenoid. When the signal went to the solenoid, manipulation of the dial allowed the lock mechanism to unlock the lock. The design and operation of more complex electronic combinations were known then and were not important features of the invention. At the time of LaGard’s invention, electronic, multinumber combination circuits were known. U.S. Patent No. 4,745,784 describes such a circuit, and the ’656 patent refers to that patent as an example of such well known circuits. 32. LaGard therefore reduced the ’656 lock to practice by November 1989. Obviously, the lock was conceived prior to La-Gard reducing it to practice. Even if La-Gard’s November 1989 prototype is not a reduction to practice, at a minimum that prototype is evidence of conception on that date. LaGard built its first prototype lock with a multiple number combination in August through September 1990. That prototype was part of a contract to supply a few locks to Mosler so that Mosler could evaluate the lock for a possible license. The locks that LaGard sent to Mosler were a reduction to practice. LaGard was diligent from November 1989 until it completed the prototypes for Mosler. 33- Clayton Miller, one of the inventors of the X-07 lock, is a principal of Lockmasters, a company that sells locks and lock parts and tools to aftermarket customers such as locksmiths. Miller has been involved in the lock industry all his life and has some patents of his own. Lockmasters is LaGard’s exclusive aftermarket distributor. As LaGard’s distributor, Miller had access to LaGard’s offices and factory, although there is no direct evidence that Miller had access to the ’656 lock. 34. Michael Harvey, one of the inventors of the X-07 lock, is an electronic engineer who has developed devices used in the Apollo space program as well as a digitally stabilized site used on the F-18. In the early 1980s, Gartner and LaGard contracted Harvey to develop an autodialer. Harvey last did consulting work for LaGard in 1982. 35. In the mid-1980s, Clayton Miller was approached by General Services Administration to do a study on entry techniques on high-security combination locks for safes. Miller, who had a long-time relationship with Gartner, was aware of the work that LaGard had done with autodialers, so he contacted Gartner for more information. Gartner gave Miller Harvey’s phone number. Miller and Harvey formed C & M Technology and developed an automanipulator, a device which uses autodialing techniques and acoustic information to detect mechanical lock positions, allowing it to open locks more rapidly than an autodialer alone. Because the automani-pulator provided a method for opening mechanical-type combination locks, Harvey and Miller determined that there was a need for a new type of next generation high security combination lock. Harvey and Miller then started working on the X-07 lock in about 1986. 36. The X-07 lock was reduced to practice at the latest on April 26, 1990 when Mr. Harvey successfully demonstrated a working prototype to those involved in the project. 37. Having heard the evidence and testimony, the Court is of the opinion and finds that the X-07 lock and the ’656 patent are two separate inventions developed independently from one another by different inventors. Plaintiff has therefore failed to show by clear and convincing evidence that La-Gard’s ’656 patent was invented by another. C. DERIVATION 38. Mas-Hamilton alleges that the ’656 patent is invalid because LaGard derived its alleged invention from others. Derivation is the taking of the invention of another and patenting it as one’s own. Lamb-Weston, Inc. v. McCain Foods, Ltd., 78 F.3d 540, 549 (Fed.Cir.1996) (Newman, J., dissenting). It is irrelevant whether or not that invention is also prior art. Id. To invalidate a patent for derivation of invention, it must be demonstrated that the named inventors acquired knowledge of the claimed invention from another, or at least so much of the claimed invention as would have made it obvious to one of ordinary skill in the art. New England Braiding Co. v. AM. Chesterton Co., 970 F.2d 878, 883 (Fed.Cir.1992); 35 U.S.C. § 102(f) (“a person shall be entitled to a patent unless ... he did not himself invent the subject matter sought to be patented”). 39. As previously discussed, having heard the evidence and testimony, the Court is of the opinion and finds that the X-07 lock and the ’656 patent are two separate inventions, developed independently from one another. Accordingly, Plaintiff has failed to show by clear and convincing evidence that the ’656 patent was derived from another. D. ON SALE BAR 40. Mas-Hamilton argues that the subject matter of the ’656 patent was “on sale” by LaGard more than one year prior to the filing of the patent application on December 17,1990, thus rendering the patent invalid under Section 102(b). Plaintiff contends that LaGard placed the ’656 patent on sale when it took the prototype lock to Mosler in November 1989. An inventor loses his right to a patent if the alleged invention was placed “on sale” in this country more than one year prior to the date of the application for patent. Buildex, Inc. v. Kason Industries, Inc., 849 F.2d 1461, 1462 (Fed.Cir.1988); 35 U.S.C. § 102(b). The inventor is strictly held to the requirement that he file his patent application within one year of any attempt to commercialize the invention. In re Mahurkar, 71 F.3d 1573, 1577 (Fed.Cir.1995). 41. An invention may be on sale where there is a definite sale or an offer to sell. Buildex, Inc. v. Kason Industries, Inc., 849 F.2d 1461, 1462 (Fed.Cir.1988). It is not necessary that a sale be consummated for the patent to be invalid; no more than a firm offer to sell may be sufficient. Id. A single offer to sell is enough to invalidate the patent whether or not the offer is accepted. A.B. Chance Co. v. RTE Corp., 854 F.2d 1307, 1311 (Fed.Cir.1988). A patent may be invalidated because the alleged invention was previously, “on sale” even though there are no commercially marketable products on hand. Barmag Bamer Maschinenfabrik AG v. Murata Mach. Ltd., 731 F.2d 831, 838 (Fed. Cir.1984). The test is whether the person offering the alleged invention thought he had a product which could be and was offered to customers. Paragon Podiatry Laboratory, Inc. v. KLM Laboratories, Inc., 984 F.2d 1182, 1187, n. 5. (Fed.Cir.1993). Such an offer for sale may invalidate the ’656 patent even if no details are disclosed. RCA Corp. v. Data General Corp., 887 F.2d 1056, 1060 (Fed.Cir.1989). 42. In the present case, Mas-Hamilton must prove by clear and convincing evidence that there was a definite sale or offer to sell more than one year before the ’656 patent application was filed, and that the subject matter of the sale or offer to sell fully anticipated the claimed invention. Mahurkar v. Impra, Inc., 71 F.3d 1573, 1576 (Fed.Cir.1995). The on sale determination depends on the totality of the circumstances, considered in view of the policies underlying § 102(b). Id. at 1577; Envirotech Corp. v. Westech Engineering, Inc., 904 F.2d 1571, 1574 (Fed.Cir.1990). These policies include: (1) discouraging removal of inventions from the public domain that the public reasonably has come to believe are freely available; (2) encouraging the prompt and widespread disclosure of invention; (3) allowing an inventor a reasonable amount of time following sales activity to determine the potential economic value of a patent; and (4) prohibiting an inventor from commercially exploiting his invention beyond the statutorily prescribed time. Id. Foremost among the policies underlying the on-sale bar is the policy of preventing inventors from exploiting the commercial value of their inventions while deferring the beginning of the statutory term. Ferag AG v. Quipp, Inc., 45 F.3d 1562, 1566 (Fed.Cir.1995). The Federal Circuit has stressed that commercialization is the central focus for determining whether the patented invention has been placed “on-sale”. Mahurkar v. Impra, Inc., 71 F.3d 1573, 1577 (Fed.Cir.1995). 43. LaGard asserts that the purpose of the transaction with Mosler was to negotiate and obtain a license for the ’656 patent technology. “[A]n assignment or sale of rights in the invention and potential patent rights is not a sale of the invention within the meaning of section 102(b).” Moleculon Research Corp. v. CBS, Inc., 793 F.2d 1261, 1267 (Fed.Cir.1986). 44. The testimony heard at trial compels the conclusion that LaGard first visited Mos-ler in November 1989 for the purpose of convincing Mosler that it had developed a product which would meet the specifications of FF-L-2740. LaGard presented to Mosler a prototype which was essentially the same device described in the ’656 patent. It offered to furnish Mosler additional prototypes for presentation to GSA. At no time did LaGard offer to sell the invention to Mosler. It offered to license either (1) the production rights to the invention, or (2) the exclusive right to market the invention to the government. Thus, the totality of the circumstances shows that Plaintiff has failed to establish by clear and convincing evidence that the ’656 patent was “on sale” more than one year prior to the filing of the patent application on December 17,1990. E. PUBLIC USE BAR 45. Mas-Hamilton argues that the subject matter of the ’656 patent was in “public use” when LaGard took a prototype lock to Mosler more than one year prior to the filing of the patent application, thus rendering the patent invalid under Section 102(b). A patent is invalid if the invention was in public use in this country more than one year prior to the date of application for patent in the United States. 35 U.S.C. § 102(b). 46. “Public use” is defined as including any use of the claimed invention by a person other than the inventor who is under no limitation, restriction or obligation of secrecy to the inventor. Lough v. Brunswick Corp., 86 F.3d 1113, 1119 (Fed.Cir.1996); Baxter International Inc. v. Cobe Laboratories, Inc., 88 F.3d 1054, 39 U.S.P.Q.2d 1437, 1440 (Fed.Cir.1996). The public use bar of § 102(b) requires that (1) the invention was used in public and (2) the use was not primarily experimental in purpose. Allied Colloids, Inc. v. American Cyanamid Co., 64 F.3d 1570, 1574 (Fed.Cir. 1995). A product is considered to be in “public use” if the completed product is commercially exploited in any way. Shatterproof Glass Corp. v. Libbey-Owens Ford Co., 758 F.2d 613, 622 (Fed.Cir.1985). 47. The totality of the circumstances must be considered in determining whether a particular event creates a public use bar. U .S. Environmental Products, Inc. v. Westall, 911 F.2d 713, 716 (Fed.Cir.1990); Allied Colloids, Inc. v. American Cyanamid Co., 64 F.3d 1570, 1574 (Fed.Cir.1995). The existence of a public use depends on how the totality of the circumstances of the case comports with the policies underlying the public use bar. Lough v. Brunswick Corp., 86 F.3d 1113, 1122, n. 5 (Fed.Cir.1996). These policies include: (1) discouraging the removal from the public domain, of inventions that the public reasonably has come to believe are freely available; (2) favoring the prompt and widespread disclosure of invention; (3) allowing the inventor a reasonable amount of time following sales activity to determine the potential economic value of a patent; and (4) prohibiting the inventor from commercially exploiting the invention for a period greater than the statutorily prescribed time. Id. 48. Factors to be considered in determining a public use include the nature of the activity that occurred in public, the public access to and knowledge of the public use, whether there was any confidentiality obligation imposed on persons who observed the use, whether progress records or other indi-cia of experimental activity were kept, whether persons other than the inventor or acting for the inventor conducted experiments, how many tests were conducted, the scale of the tests compared with commercial conditions, the length of the test in comparison with tests of similar products, and whether payment was made for the product of the tests. Allied Colloids, Inc. v. American Cyanamid Co., 64 F.3d 1570, 1574 (Fed.Cir.1995). 49. The testimony heard at trial compels the conclusion that LaGard visited Mosler in November 1989 for the purpose of convincing Mosler that it had developed a product which would meet the specifications of FF-L-2740. LaGard presented to Mosler a prototype which was essentially the same device described in the ’656 patent. It offered to furnish Mosler additional prototypes for presentation to GSA. At no time did LaGard offer to sell the invention to Mosler. It offered to license either (1) the production rights to the invention, or (2) the exclusive right to market the invention to the government. While there was no proof offered that a confidentiality agreement was entered into by and between LaGard and Mosler, the Court is convinced, based on past practices in the industry, and upon the testimony of La-Gard representatives, Herrmann and Gart-ner, and that because of the litigious nature of those engaged in the industry, that the design of the prototype would be kept confidential. This conclusion makes sense in light of the considerable research and expenditure that went into developing the ’656 lock. To find otherwise would mean that LaGard was prepared to part with its concept for a mere $10,000, a finding which the Court is unprepared to make based on the evidence and testimony presented at trial. Further, Mos-ler was not given unlimited, unrestricted use of the ’656 patent. Rather, it is clear to the Court that Mosler was only given a limited, restricted use consistent with LaGard’s purpose of interesting Mosler in a license. Therefore, the Plaintiff has failed to establish by clear and convincing evidence that the product was in public use more than one year prior to LaGard filing its patent application. F. BEST MODE 50. Mas-Hamilton asserts that the ’656 patent is invalid for failing to meet the best mode requirement. Under 35 U.S.C. § 112, a patent specification must set forth the best mode contemplated by the inventor of carrying out his invention. The purpose of the best mode requirement is to restrain inventors from applying for patents while at the same time concealing from the public preferred embodiments of the invention which they have in fact conceived. De George v. Bernier, 768 F.2d 1318, 1324 (Fed. Cir.1985). The best mode requirement is intended to insure that a patent applicant plays “fair and square” with the patent system — it is a requirement that the quid pro quo of the patent grant be satisfied — one must not receive the right to exclude others unless at the time of filing he has provided an adequate disclosure of the best mode known to him of carrying out his invention. Amgen, Inc. v. Chugai Pharmaceutical Co., Ltd., 927 F.2d 1200, 1209-10 (Fed.Cir.1991). 51. There is a two-part test for determining whether the best mode requirement has been violated: (1) whether, at the time the inventor filed his patent application, he knew of a mode of practicing his claimed invention that he considered- to be better than any other; and (2) is the disclosure adequate to enable one skilled in the art to practice the best mode or has the inventor concealed his preferred mode from the public? Chemcast Corp. v. Arco Industries Corp., 913 F.2d 923, 926 (Fed.Cir.1990). Determining whether a patent complies with the best mode requirement involves two underlying factual inquiries: (1) it must be determined whether, at the time the patent application was filed, the inventor had a best mode of practicing the claimed invention; and (2) if the inventor had a best mode of practicing the claimed invention, it must be determined whether the specification of the patent adequately disclosed what the inventor contemplated as the best mode so that those having ordinary skill in the art can practice it. United States Gypsum v. National Gypsum Co., 74 F.3d 1209, 1212 (Fed. Cir.1996). 52. Plaintiff contends that the ’656 patent discloses that the solenoid housing is preferably made from brass. However, if that instruction were followed, Plaintiff argues that the mechanism would not work. One of the models constructed by LaGard before the patent application was filed used a solenoid housing made of brass and iron or steel, and the alleged inventors were aware of that model. Consequently, Plaintiff maintains that the alleged inventors were aware of a better mode of practicing the alleged invention disclosed in the ’656 patent. By disclosing an inoperable embodiment, Plaintiff asserts that the alleged inventors concealed the best mode. See Chemcast Corp. v. Arco Industries Corp., 913 F.2d 923, 926 (Fed.Cir.1990). 53. Plaintiff also argues that toleraneing (how accurately parts must be made for them to work properly) of the solenoid housing and the lever is critical to proper operation of the ’656 lock. Specifically, testimony at trial indicated that the lock shown in the ’656 patent’s exemplary embodiment would jam because continued rotation of the dial while the detent ball is still engaged with the cam wheel causes the solenoid housing to contact the right side of the housing. There is no disclosure in the ’656 patent which describes the necessary and preferred way of building the mechanism, which was known to the alleged inventors before the patent application was filed. Plaintiff contends that this information is critical to practicing the ’656 patent lock. 54. There is no disclosure in the ’656 patent concerning how long the solenoid should be energized. Plaintiff contends that this is a very important consideration to enable the solenoid and lock to operate. Prior to filing the ’656 patent application, Plaintiff argues that the alleged inventors knew that the solenoid should only be energized for a short, predetermined time, and had determined by trial and error in connection with a prototype that solenoid energization of about three seconds was the practical minimum for activation of the lock. This timing was incorporated in the software associated with a LaGard model before the patent application was filed. Plaintiff insists that this information is critical to practicing the ’656 patent lock. Consequently, the alleged inventors were well aware of this critical and necessary requirement and a better way of practicing the alleged invention, but concealed and failed to disclose it. 55. The testimony heard at trial compels the conclusion that one of ordinary skill in the art would appreciate that the solenoid must contain some magnetic material in order to work properly. Likewise, the lack of detailed tolerancing or solenoid energization timing information in the ’656 patent would not prevent one of ordinary skill in the art from practicing the ’656 patent. Therefore, the Court finds that Plaintiff has failed to establish by clear and convincing evidence that the ’656 patent is invalid for failing to meet the best mode requirement. G. ENABLEMENT 56. Mas-Hamilton asserts that the ’656 patent is invalid for failing to meet the enablement requirement. The specification of a patent must contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same. 35 U.S.C. § 112. In order to be considered enabling, a patent must give persons of ordinary skill in the relevant art enough information to practice the invention disclosed in the specification without undue experimentation. In re Alton, 76 F.3d 1168, 1172, n. 5 (Fed.Cir.1996). A patent is invalid if a person skilled in the pertinent art, using the knowledge available to that person, and the disclosure in the patent document, could not make and use the invention without undue experimentation. Northern Telecom, Inc. v. Datapoint, Corp., 908 F.2d 931, 941 (Fed.Cir.1990). The purpose of this requirement is to insure that the inventor provides sufficient information about the claimed invention. Scripps Clinic & Research Foundation v. Genentech, Inc., 927 F.2d 1565, 1571 (Fed.Cir.1991). It is not sufficient that a person following the disclosure might obtain the results set forth in the claims; it must invariably happen. Gubel-mann v. Gang, 56 C.C.P.A. 1013, 408 F.2d 758, 766 (C.C.P.A.1969). 57. Plaintiff argued at trial that the ’656 patent provides insufficient information concerning solenoid timing, construction of the solenoid housing, and relative tolerancing of the solenoid housing and lever in order to enable a person of ordinary skill in the art to build a working lock mechanism. 58. Having heard the testimony at trial, the Court finds that the information contained in the ’656 patent would allow one of ordinary skill in the art to practice the ’656 patent. Thus, Plaintiff has failed to establish by clear and convincing evidence, that the ’656 patent is invalid for failing to meet the enablement requirement. H. INDEFINITENESS 59. Mas-Hamilton asserts that the claims at issue are invalid because they are indefinite as written or as asserted by LaGard. Patent claims must particularly point out and distinctly claim the subject matter which the patentee regards as his invention. 35 U.S.C. § 112. A claim is invalid for failing to meet this requirement if those in the relevant art would not understand what is being claimed in the patent. Amgen, Inc. v. Chugai Pharmaceutical Co. Ltd., 927 F.2d 1200, 1217 (Fed.Cir.1991). Thus, the requirement is that the language of the claims must make it clear what subject matter they encompass. PPG Industries, Inc. v. Guardian Industries Corp., 75 F.3d 1558, 1562 (Fed.Cir.1996). The statute sets forth a requirement for precision and definiteness of claim language. Id. 60. The Patent Office understood the terms used in the ’656 patent claims. There is a “heavy presumption against [Mas-Hamilton] in arguing that the patents and claims do not comply with 35 U.S.C. § 112 where the Examiner reviewed the adequacy of the descriptions and found the patent descriptions to be definite and allowed the patents thereafter.” Water Tech. Corp. v. Calco Ltd., 658 F.Supp. 961, 972 (N.D.Ill.1986), aff'd in part, rev’d in part, 850 F.2d 660 (Fed.Cir.), cert. denied, 488 U.S. 968, 109 S.Ct. 498, 102 L.Ed.2d 534 (1988). 61. Based on the evidence and testimony presented at trial, the Court finds that the ’656 patent claims make dear what subject matter is covered and encompassed in the patent. Plaintiff has therefore failed to establish by clear and convincing evidence that the ’656 patent is invalid on grounds of indefiniteness. I. ANTICIPATION/OBVIOUSNESS 62. A patent may be found invalid based upon various types of prior art. 35 U.S.C. § 102. A patent may also be invalid if the differences between the subject matter patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art. 35 U.S.C. § 103. 63. Plaintiff argues that according to La-Gard, the primary difference between the alleged invention in the ’656 patent and the prior art was the concept of positively moving" the lever into contact with the cam wheel only after the proper combination was entered. Plaintiff contends that LaGard admitted that it has in its possession “voluminous” prior art documents showing this concept. However, Plaintiff claims that LaGard failed to produce those documents, in violation of this Court’s order. Thus, Plaintiff invites the Court to draw an adverse inference that those documents, if produced, would invalidate the asserted claims of the ’656 patent either as an anticipation or as obvious. 64. Having heard the testimony and arguments at trial, the Court finds that there is no evidence that the ’656 patent is invalid due to prior art. Further, the Court will draw no adverse inference from LaGard’s production of documents, or lack thereof, during discovery. Accordingly, the Court finds that Plaintiff failed to establish by clear and convincing evidence that the ’656 patent is invalid due to anticipation or obviousness. CONCLUSION ON VALIDITY 65. Based on the evidence produced at trial, and for the reasons expressed above, the Court finds that Plaintiff has failed to establish by clear and convincing evidence that the ’656 patent is invalid for any reason. Thus, Plaintiff has failed to rebut the presumption that a patent issued by the Patent Office is valid. Accordingly, the Court finds that the ’656 patent is valid. IY. PATENT INFRINGEMENT A. INFRINGEMENT 66. The patent statutes provide that whoever, without authority from the patent owner, makes, uses or sells any patented invention within the United States during the term of the patent, infringes the patent. 35 U.S.C. § 271. Patent infringement is determined by comparing the accused product with the invention set forth in the “claims” of the patent. A patent “claim” is a group of words which defines the boundary of the patent and which determines what the invention is. General Foods Corp. v. Studiengesellschaft Kohle mbH, 972 F.2d 1272, 1274 (Fed.Cir.1992). The claims are the numbered paragraphs which appear at the end of the patent and which are required to particularly point out and distinctly claim the subject matter which the patentee regards as his invention. Autogiro Co. of America v. United States, 181 Ct.Cl. 55, 384 F.2d 391, 395-96 (Ct.Cl.1967). 67. To prevail, LaGard must prove by a preponderance of the evidence that Mas-Hamilton has infringed upon one or more of the claims of the ’656 patent. Hughes Aircraft Co. v. United States, 717 F.2d 1351, 1361 (Fed.Cir.1983). The burden always is on LaGard to show infringement. Under Sea Industries, Inc. v. Dacor Corp., 833 F.2d 1551, 1557 (Fed.Cir.1987). 68. Infringement is a question of fact. Hilton Davis Chem. Co. v. Warner-Jenkinson Co., 62 F.3d 1512, 1520 (Fed.Cir.1995) (en banc), cert. granted, 516 U.S. 1145, 116 S.Ct. 1014, 134 L.Ed.2d 95 (1996). 69. There are two elements of a patent ease: (1) construing the patent, and (2) determining whether infringement occurred. Markman v. Westview Instruments, Inc., 517 U.S. 370, 116 S.Ct. 1384, 134 L.Ed.2d 577 (1996). Thus, determining infringement is a two-step process: the first step is to determine the meaning and scope of the patent claims; the second step is to compare the properly construed claim to that which it is asserted to infringe. Markman v. Westview Instruments, Inc., 52 F.3d 967, 976 (Fed.Cir.1995) (en banc), aff'd., 517 U.S. 370, 116 S.Ct. 1384, 134 L.Ed.2d 577 (1996). Infringement may be literal where every limitation in a claim is met in the accused device exactly, or infringement may be proved under the doctrine of equivalents. Pennwalt Corp. v. Durand-Wayland, Inc., 833 F.2d 931, 935 (Fed.Cir.1987) (en banc); Hilton Davis Chem. Co. v. Warner-Jenkinson Co., Inc., 62 F.3d 1512 (Fed.Cir.1995) (en banc), cert. granted, 516 U.S. 1145, 116 S.Ct. 1014, 134 L.Ed.2d 95 (1996). B. CLAIM CONSTRUCTION 70. The scope of the patent is limited to the invention covered by the claim. Thus, the language of the claim defines the scope of the protected invention. Bell Communications Research, Inc. v. Vitalink Communications Corp., 55 F.3d 615, 619-20 (Fed. Cir.1995); York Products, Inc. v. Central Tractor Farm & Family Center, 99 F.3d 1568, 1572 (Fed.Cir.1996). 71. In interpreting an asserted claim, the court should look first to the intrinsic evidence of record, i.e., the patent itself, including the claims, the patent specification, and the prosecution history of the patent. Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed.Cir.1996); Athletic Alternatives, Inc. v. Prince Manufacturing, Inc., 73 F.3d 1573, 1578 (Fed.Cir.1996). The court must also look to the words of the claims themselves, both asserted and non-asserted, to define the scope of the patented invention. Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed.Cir.1996). 72. In construing a claim, claim terms are given their ordinary and accustomed meaning until examination of the specification, prosecution history, and other claims indicates that the inventor intended otherwise. Transmatic, Inc. v. Gulton Industries, Inc., 53 F.3d 1270, 1277 (Fed.Cir.1995); Gentex Corp. v. Donnelly Corp., 69 F.3d 527, 530 (Fed.Cir.1995). The court must construe the claim language according to the standard of what those words would have meant to one skilled in the art as of the application date of the patent. Wiener v. NEC Electronics, Inc., 102 F.3d 534, 539 (Fed.Cir.1996). Although words in a claim are generally given their ordinary and customary meaning, a patentee may choose to be his own lexicographer and use terms in a manner other than their ordinary meaning, as long as the special definition of the term is clearly stated in the patent specification or prosecution history. Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed.Cir.1996). It is always necessary to review the specification to determine whether the inventor has used any terms in a manner inconsistent with their ordinary meaning; the specification acts as a dictionary when it expressly defines terms used in the claims or when it defines terms by implication. Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed.Cir.1996). 73. Included within an analysis of the prosecution history may be an examination of the prior art cited. Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1583 (Fed.Cir.1996). 74. Construction of a patent, including terms of art within its claim, is exclusively within the province of the court. Markman v. Westview Instruments, Inc., 517 U.S. 370, 116 S.Ct. 1384, 134 L.Ed.2d 577 (1996). Thus, the construction of patent claims, as well as the meaning and scope of a disputed technical term or terms of art in a patent claim, are questions of law. Applied Materials, Inc. v. Advanced Semiconductor Materials, 98 F.3d 1563, 1572 (Fed.Cir.1996). 75. The claims of the ’656 patent contain a number of terms which are disputed in the present action. The Court finds that the claim terms listed below have the following meanings: a. “Blocking Element” (Claim 1) 76. In the ’656 patent, the blocking element is a cantilever arm formed as an integral part of the lever which blocks movement of the lever. b.“Combination” (Claims 3k, k3) 77. Claims 34 and 43 of the ’656 patent define certain claim elements, particularly the movable link member, the movable element, and the movable projecting element, in terms of their functional operation before and after entry of a “combination”. Consequently, the claim term “combination” represents a limitation on the functional definition, since the claims use the word “combination” as part of functional phrases. 78. The ’656 patent specification speaks to a combination code. Col. 2, line 48; Col. 4, line 61; Col. 5, line 33; Col. 6, line 40, Col. 7, line 24. The code is entered by entering the proper sequence. Col. 7, line 19. The ’656 patent incorporates by reference U.S. Patent No. 4,745,784 for some of the lock details. The ’784 patent defines the combination in terms of “a predetermined sequential series of rotations”. PX 9, col. 1, lines 19-21. The combination is also defined in terms of a “predetermined, sequential order corresponding to the code”. Col. 4, lines 66-68. 79. The prosecution history of the ’656 patent also describes a “combination code”. PX 45, p. 111. The prosecution history references a number of prior art “combination” lock patents which require a sequence of letters or numbers to be entered to open the lock, e.g., PX 45, p. 49 (Diesel ’702); p. 50 (Lee ’114); p.50 (Gartner ’667); p.51 (Uyeda ’785); p.51 (Yueda ’176); p.52 (Gartner ’984); p. 172 (Herlong). Prior art, whether or not cited in the specification or the file history, may be used to demonstrate how a disputed term is used by those skilled in the art. McGill, Inc. v. John Zink Co., 736 F.2d 666 (Fed.Cir.1984). 80. General and technical dictionaries may be relied upon to determine the meaning of technical and other terms. Hoechst Celanese Corp. v. BP Chemicals Ltd., 78 F.3d 1575, 1580 (Fed.Cir.1996). 81. According to dictionary definitions, a “combination” is a “sequence of letters or numbers chosen in setting a lock”. Thus, the Court finds that as used in the claims of the ’656 patent, “combination” means an ordered sequence of letters or numbers which must be entered to open the lock. This term cannot be construed merely to cover a single switch closure. c. “Correct Combination” (Claim 3) 82. The claim term “correct combination” defines the function of the lever moving element moving means and defines when the moving element is activated. Thus, the term defines and limits the function of a particular claim element. This term should be construed to have the same meaning as defined above for “combination”, and refers to a particular type of combination which will cause the lock to open. Thus, “correct combination”, as used in the ’656 patent claims, means the proper ordered sequence of letters or numbers which must be entered to open the lock. d. “Detent” (Claim 1) 83. As defined in the ’656 specification, a “detent” is a ball comprising a spherical or curved surface 96 which can project, extend or protrude outwardly of the solenoid housing. Col. 6, lines 12-22; Col. 7, lines 31-34; Col. 7, lines 43-46; Col. 7, lines 51-56; Figures 1, 3, 4-7. In the specification, “detent” is not described or illustrated in any way other than as a spherical ball capable of being projected above the surface of the solenoid housing. Thus, this definition is of controlling significance. McGill, Inc. v. John Zink Co., 736 F.2d 666, 674 (Fed.Cir.1984). 84. In the usual engineering sense, a “de-tent” is a spring-loaded element that is driven into either a recessed area in another component or a slot or slide. A detent is almost without exception spring-loaded, or a spring-loaded component that goes into a mating hold slot, ridge, or the like. A detent may also be described as a mechanism that slides two pieces of metal together with a spring and ball to lock the pieces of metal together. A tooth on a gear is not considered a “detent”. 85. The claims of the ’656 patent also define a “detent” in terms of a member movable from one position to another (Claim 1) and where the “detent” protrudes from another member (Claims 8, 9, 14, 21). The claims of the ’656 patent also define a “de-tent” in the conventional sense, as “spring-biased”. See claims 10, 11, 12, 13, 15, 16, 17, 18. Both asserted and non-asserted claims may be used to define claim terms. Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed.Cir.1996). 86. Thus, as used in the ’656 patent claims, “detent” means a separate spring-biased element such as a ball, which is movable from one position to another and that goes into a mating hole, slot or ridge in the blocking element and is capable of being driven by the solenoid into a position where it can contact the detent engaging member on the cam. e. “Detent Engaging Member’’ (Claim 1) 87. As used in the claims of the ’656 patent, the detent engaging member is a member located on the cam wherein rotation of the dial drives the member against a detent which has been moved to the detented position. f. “Detented Position” (Claim 1) 88. In the ’656 patent specification, the “detented” or engagement position is defined as the position where the spherical or curved surface detent ball 96 can project, extent or protrude outwardly of the solenoid housing. Col. 6, lines 16-19. 89. Thus, as used in the ’656 patent claims, the “detented position” is the location that the detent extends, projects or protrudes to by the solenoid by entry of the combination so that the detent can be contacted by the detent engaging member on the cam. g. “Electromechanical Device ” (Claim 33) 90. This term is not mentioned in the specification of the ’656 patent. The only type of electromechanical device described in the specification is a solenoid. Thus, this term should be construed to be no broader than a solenoid and equivalent structures. Consequently, as used in the ’656 patent “electromechanical device” means a device which imparts mechanical movement upon application of an electrical signal, such as a solenoid, to move the link element after entry of the combination. h. “Electronically Activated” (Claim 3) 91. This limitation is used to define how the lever moving element is activated to cooperate with the moving means. i. “Electronically Actuated” (Claim 1) 92. This claim term defines how the solenoid is operated by entry of a predetermined combination. The term “electronically” has the same meaning as that term is used in Claim 3. The meaning of claim terms must be consistent throughout the patent. McGill, Inc. v. John Zink Co., 736 F.2d 666, 674 (Fed.Cir.1984). j. “Electronic Combination Lock” (Claims 3, 3k, 35, 38, 39, kS) 93. The ’656 patent specification states that the “invention relates generally to electronic combination locks”. Col. 1, lines 6-7. The “electronic dial combination lock” is described as “a dial having divisions to enter a combination code to gain entrance to the secured area .... A circuit contained in the secured region senses the electrical connections and detects when a certain subset of connections has been made corresponding to the lock’s combination and initiates an electrical signal within the secured region. The signal may be used, e.g., to operate a solenoid _”. Col. 1, lines 15-31. Throughout the specification, the lock is described in terms of its electronic and combination features, e.g., that the solenoid plunger is actuated “when the correct combination is entered into the printed circuit board and an appropriate signal is produced from an output on the printed circuit board to the coil 108 in the solenoid, as would be known to one skilled in the art”. Col. 6, lines 39-43. Consequently, the entire specification of the patent describes the “invention” as part of an “electronic combination lock”, not as a separate mechanical mechanism. 94. It is also appropriate to determine whether the term in the preamble serves to define the invention that is claimed or is simply a description of the prior art. Ap plied Materials Inc. v. Advanced Semiconductor, 98 F.3d 1563, 1573 (Fed.Cir.1996). Here, the patentees used the preamble to define the “invention” itself, not simply to describe prior art. 95. The patentee chose to define its alleged “invention” as an “electronic combination lock”, using both the preamble to define the electronic and combination aspects of the lock, as well as the remainder of the claim limitations. Consequently, the preamble forms a limitation of the claim. 96. Where the claim refers back to the preamble, e.g. by stating “said” [preamble], the preamble phrase becomes a limitation to the claim. Bell Communications Research, Inc. v. Vitalink Communications Corp., 55 F.3d 615, 621 (Fed.Cir.1995). The last paragraph of Claim 3 refers to “said combination”. The claim language also refers back to electronic activation of the moving element. Claim 34 and the claims dependent on that claim (Claim 35, 38, and 39) refer back to “the combination” of the preamble. The body of Claim 43 similarly refers back to “the combination”. Consequently, in all of the claims, if no “combination” is present, there is nothing to describe the function of the mechanical elements, and the claim would not define an operable device. Thus, “electronic combination lock” must be interpreted to form a limitation of each of the claims. k.“Electronically Operated Lock” (Claims 1, SI) 97. The entire specification of the ’656 patent describes the “invention” in terms of a lock which is electronically operated; no other type of lock is mentioned in the context of the “invention”. 98. The description “electronically operated lock” should also be interpreted as a limitation to the claim. In Claim 1, the “invention” is described as being “in an electronically operated lock”. Consequently, the alleged “invention” cannot exist apart from the electronically operated lock. Further, the solenoid is described as “electronically actuated”. If the lock were not electronic, this claim limitation would be meaningless. Thus, the preamble terms must be limitations to the claim since they are required to give meaning to the claim and properly define the invention. In re Paulsen, 30 F.3d 1475, 1479 (Fed.Cir.1994). Claim 31 also defines the “invention” as “in an electronically operated lock”. Thus, both the preamble and the body of this claim are also used to define the subject matter of the claimed “invention”. Bell Communications Research, Inc. v. Vitalink Communications Corp., 55 F.3d 615, 620 (Fed.Cir.1995). l. “Electrically Operable” (Claim 35) 99. This phrase is only used in Claim 35, and is not referenced in the specification of the patent. The use of this terminology shows an intent to differentiate “electrically” from “electronically”. m. “Engagement Position” (Claim 31) 100. The specification of the ’656 patent uses this term as synonymously with “detented position”. See, Col. 6, lines 18-19. Thus, “engagement position” means the location that the detent extends, projects or protrudes to by the solenoid by entry of the combination so that the detent can be contacted by the detent engaging member on the cam. n. “Lever Movement Blocking Element” (Claim 1) 101. This claim terminology, which is only used in this claim, has the same meaning as “blocking element” defined above. Thus, as used in the claims, “lever movement blocking element” means the cantilever arm which is formed as an integral part of the lever which blocks movement of the lever. o. “Lever Operating Means” (Claim 1) 102. This claim element defines a “lever operating means for positively driving said lever toward said cam in response to continued rotation”. The use of the word “means” triggers a presumption that the inventor used the term advisedly to invoke the statutory mandate for means-plus-funetion clauses. York Prods., Inc. v. Central Tractor Farm & Family, Ctr., 99 F.3d 1568, 1574 (Fed.Cir.1996). LaGard concedes that this claim element is in means-plus-format and therefore subject to the requirements of 35 U.S.C. § 112 ¶ 6. LaGard’s Supplemental Reply to Mas-Hamilton’s Opposition to La-Gard’s Summary Judgment Motion, p. 8. 103. 35 U.S.C. § 112 ¶ 6 provides: An element in a claim for a combination may be expressed as a means or a step for performing a specified function without the recital of structure, material or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof. This is a universal requirement, and applies whether the claim language is being interpreted for purposes of infringement or validity. In re Donaldson Co., Inc. 16 F.3d 1189, 1193 (Fed.Cir.1994) (en banc). 104. “Means-plus-funetion” language means that the element is defined in terms of a means for performing a particular function. For a means-plus-function limitation to read on an accused device, the accused device must employ means identical or equivalent to the structures, materials or acts described in the patent specification, and the accused device must perform the identical function that is specified in the claims. King Instruments Corp. v. Perego, 65 F.3d 941, 945 (Fed.Cir.1995). Thus, the “means” language in the ’656 patent claims which recites an element for performing a particular function does not cover all means for performing the specified function; rather, the claims are strictly confined to structures expressly disclosed in the ’656 patent specification and corresponding equivalents. Symbol Technologies, Inc. v. Opticon, 935 F.2d 1569, 1575 (Fed.Cir.1991); Intel Corp. v. U.S.I.T.C., 946 F.2d 821, 841 (Fed.Cir.1991). Consequently, § 112 ¶ 6 requires that means-plus-function claims be construed in view of the structure disclosed in the specification of the ’656 patent. Alpex Computer Corp. v. Nintendo Co., Ltd., 102 F.3d 1214, 40 U.S.P.Q.2d 1667, 1672 (Fed.Cir.1996). 105.In the lever operating means described in the ’656 patent specification, when the solenoid is actuated, the solenoid housing, which is also called a rigid body or element, slides in a channel to positively drive the lever from its disengaged position to a position for engaging the nose part of the lever with a slot on the cam wheel in response to dial rotation after the combination has been entered. When the solenoid is continuously activated after entry of the proper combination, the solenoid housing is driven through a detent ball by rotation of the dial cam to push against the lower end of the cantilever arm causing the lock lever to rotate about its pivot point. Once the protrusion on the cam wheel passes the detent ball (also called a “flag”), the solenoid housing immediately returns to its unactuated position. 106. The function of this means is to “positively drive” (as defined below) the lever toward the cam in response to continued dial rotation after the combination has been entered by means of the described mechanism. p. “Lever Retaining Means” (Claim 1) 107. This claim element is described as a “lever retaining means for normally holding said lever out of engagement with said cam LaGard concedes that this claim element is in the § 112 ¶ 6 means-plus-function format. LaGard’s Reply Re Summary Judgment Motion on Infringement (DE # 127), p. 12; LaGard’s Supplemental Reply to Mas-Hamilton’s Opposition to LaGard’s Summary Judgment Motion (DE # 142), p. 8. 108. In the ’656 patent specification, this “means” is described as a lever that is held out of contact with the dial cam by a cantilever arm. The cantilever arm is an integral part of the lever and includes a movable spring-loaded pin contained within a bore. 109. The function of this means is to normally hold the lever out of engagement with the cam during rotation of the dial until after the combination has been entered using the described mechanism. q. “Lever Moving Element” (Claim 31) 110. This claim limitation defines a lever moving element “for positively driving said lever toward said cam in response to con