Full opinion text
MEMORANDUM OPINION SUE L. ROBINSON, Chief Judge. I. INTRODUCTION On July 25, 2001, plaintiff Arthrocare Corporation (“Arthrocare”) filed this action against defendant Smith & Nephew, Inc. (“Smith & Nephew”) alleging willful direct, contributory, and inducing infringement of certain claims of U.S. Patent Nos. 5,697,536 (the “’536 patent”), 5,697,882 (the “ ’882 patent”) and 6,224,592 (the “ ’592 patent”). (D.I.l) Smith & Nephew answered the complaint on September 13, 2001 denying the infringement allegations and asserting five affirmative defenses including noninfringement, invalidity, misuse, unenforceability based upon inequitable conduct, and unclean hands. (Id.) Smith & Nephew also asserted counterclaims for a declaratory judgment that the patents in suit are invalid and not infringed by any act of Smith & Nephew and that the ’592 patent is unenforceable due to inequitable conduct. (D.I.10) On September 26, 2001, Arthrocare denied Smith & Nephew’s counterclaims. (D.I.20) With the court’s permission, Smith & Nephew amended their answer on November 27, 2002 to add counterclaims for antitrust violations under 15 U.S.C. § 1 of the Sherman Act. (D.I.219) ArthroCare is organized under the laws of the State of Delaware with its principal place of business in California. (D.I. 1 at ¶2) Smith & Nephew is also organized under the laws of State of Delaware with its principal place of business in Massachusetts. (Id. at ¶ 3) The court has jurisdiction over this case pursuant to 28 U.S.C. §§ 1331, 1338(a), and 2201(a). The court separated the issues raised by the parties into two phases, the first phase to include the issues of infringement, validity, and inequitable conduct and the second phase to include the issues of damages, willfulness, and antitrust counterclaims. From April 30, 2003 through May 9, 2003, the parties tried the issues of infringement and invalidity before a jury. The court ruled on May 12, 2003 that the parties could submit their inequitable conduct cases on the briefs limited to the record created at trial. (See D.I. 418 at 1071-02) Currently before the court are the parties’ post-trial motions on the issues of infringement, invalidity, and inequitable conduct. (D.1.424, 427, 432, 437, 455, 458) II. BACKGROUND A. Electrosurgery In General The patents in suit generally relate to electrosurgery and to surgical devices and methods that employ high frequency voltage to cut and ablate tissue. These devices are of either a monopolar or a bipolar nature. A monopolar device, as the name suggests, consists of only a single electrode. It directs an electric current from the exposed or active electrode through a patient’s body to a return electrode externally attached to the patient’s body. In contrast, a bipolar device consists of two electrodes. An active electrode in contact with the patient’s tissue transmits an electric current through the patient’s tissue to a return electrode also in contact with the patient’s tissue. When using either type of device, the target region must be treated with isotonic saline to maintain an isotonic environment around the tissue and to keep the area in clear view. Electrosurgical techniques are advantageous because they reduce patient bleeding and the trauma associated with operations involving cutting. At the same time, a diverse range of risks may be implicated. With monopolar devices, electric current may flow in undefined paths through a patient’s body. Also, high voltages typically must be applied to generate a current suitable for cutting or ablation using either monopolar or bipolar devices. Such high voltage may damage or destroy surrounding tissue. B. The Patents In Suit The patents in suit involve improvements over the monopolar and bipolar devices of the prior art. Specifically, the ’536 patent claims an electrosurgical system comprising an electrosurgical probe, a return electrode, and a fluid delivery element. The ’592 and ’882 patents, in turn, claim methods of using the system disclosed in the ’536 patent to apply electrical energy adjacent to the target tissue without submerging the target tissue in an electrically conducting irrigant. Each patent will be considered in further detail as relevant to the parties’ post-trial motions. 1. The’536 Patent The ’536 patent, entitled “System and Method for Electrosurgical Cutting and Ablation,” was issued on December 16, 1997 with Philip E. Eggers and Hira V. Thapliyal as inventors. It was originally filed on November 18, 1996. The ’536 patent traces priority to the now abandoned U.S. Application No. 817,575. It was granted with sixty-four claims on December 16,1997. On December 23, 1999, a third party filed a request for an ex parte reexamination based solely upon prior art. The United States Patent and Trademark Office (“PTO”) granted this request and, after reexam, issued a “Notice of Intent to Issue an Ex Parte Reexamination Certificate” as to all original claims. Claims 46, 47, and 56 are presently asserted and are apparatus type claims. Claims 46 and 56 depend from claim 45. Claim 47 depends from claim 46. These claims read as follows: 45. An electrosurgieal system for applying electrical energy to a target site on a structure within or on a patient’s body, the system comprising: a high frequency power supply; an electrosurgieal probe comprising a shaft having a proximal end and a distal end, and a connector near the proximal end of the shaft electrically coupling the electrode terminal to the electrosurgieal power supply; a return electrode electrically coupled to the electrosurgieal power supply; and an electrically conducting fluid supply for directing electrically conducting fluid to the target site such that the electrically conducting fluid generates a current flow path between the return electrode and the electrode terminal. 46. An electrosurgieal system as in claim 45, wherein the return electrode forms a portion of the shaft of the electrosurgieal probe. 47. An electrosurgieal system as in claim 46 further including an insulating member circumscribing the return electrode, the return electrode being sufficiently spaced from the electrode terminal to minimize direct contact between the return electrode and the patient’s tissue.. 56. The electrosurgieal system of claim 45 wherein the target site is selected from the group consisting essentially of the abdominal cavity, thoracic cavity, knee, shoulder, hip, hand, foot, elbow, mouth, spine, ear, nose, throat, epidermis and dermis of the patient’s body. (’536 patent, col. 18 at 11. 13-36; col. 19 at 11. 11-15) The court construed disputed terms of the ’536 patent to ascertain both their meaning and scope. (D.I.353) The most significant constructions for the purposes of resolving the parties’ post-trial motions are as follows: 1. The term “electrosurgieal system” shall be given its “ordinary definition” and construed to mean “an assemblage or combination of things or parts forming a unitary whole.” 2. The term “return electrode” shall be construed to mean “an electrode having a larger area of contact than an active electrode, thus affording a lower current density.” 3. The term “connector” shall be construed to mean “a structure that electrically links the electrode terminal to the high frequency power supply.” 4. The phrases “spacing a return electrode away from the body structure” and “the return electrode is not in contact with the body structure” shall be construed to mean that the return electrode is not to contact the body at all during the performance of the claimed method. 5. The term “electrically conducting fluid” and “electrically conductive fluid” shall be construed to mean “any fluid that facilitates the passage of electrical current.” 2. The’882 Patent The ’882 patent, entitled “System and Method for Electrosurgical Cutting and Ablation,” was issued on December 16, 1997 with Philip E. Eggers and Hira V. Thapliyal as inventors. It was originally filed on November 22, 1995 and traces priority to the same original application as the ’536 patent, namely U.S. Application No. 817,575. The ’882 patent was granted with fifty-six claims on December 16, 1997. Claims 13, 17, and 54 are presently asserted. All are method type claims. Claims 13 and 17 depend from claim 1 and claim 54 depends from both claim 1 and claim 28. These claims recite: 1. A method for applying energy to a target site on a patient body structure comprising: providing an electrode terminal and a return electrode, electrically coupled to a high frequency voltage source; positioning the active electrode in close proximity to the target site in the presence of an electrically conducting fluid; and applying a high frequency voltage between the electrode terminal and the return electrode, the high frequency voltage being sufficient to vaporize the fluid in a thin layer over at least a portion of the electrode terminal and to induce the discharge of energy to the target site in contact with the vapor layer. 13. The method of claim 1 wherein at least a portion of the energy induced is in the form of photons having a wavelength in the ultraviolet spectrum. 17. The method of claim 1 wherein the high frequency voltage is at least 200 volts peak to peak. 28. A method for applying energy to a target site on a patient body structure comprising: providing an electrode terminal and a return electrode electrically coupled to a high frequency voltage source; positioning the electrode terminal in close proximity to the target site in the presence of an electrically conducting fluid; and applying a high frequency voltage between the electrode terminal and the return electrode, the high frequency voltage being sufficient to impart sufficient energy into the target site to ablate the body structure without causing substantial tissue necrosis below the surface of the body structure underlying the ablated body structure. 54. The method of claims 1 and 28 further comprising evacuating fluid generated at the target site with a suction lumen having a distal end adjacent the electrode terminal. (’882 patent, col. 24 at 11. 5-18; 54-56, 64-65; col. 25 at 11. 38-51; col. 28 at 11. 9-10) Pursuant to multiple certificates of correction granted after the ’882 patent originally issued, the language recited in several claims was corrected. Of interest to the parties’ post-trial motions, claim 1 was corrected on April 7, 1998. Claim 54 was corrected on May 2, 1998. For sake of clarity, the corrected language is shown below in bold with the original language in parentheses. 1. A method for applying energy to a target site on a patient body structure comprising: providing an electrode terminal and a return electrode electrically coupled to a high frequency voltage source; positioning the [active] electrode terminal in close proximity to the target site in the presence of an electrically conducting [terminal] fluid; and applying a high frequency voltage between the electrode terminal and the return electrode, the high frequency voltage being sufficient to vaporize the fluid in a thin layer over at least a portion of the electrode terminal and to induce the discharge of energy to the target site in contact with the vapor layer. 54. The method of claims [1 and 28] 23 or 48 further comprising evacuating fluid generated at the target site with a suction lumen having a distal end adjacent the electrode terminal. (’882 patent, Certificates of Correction dated August 25, 1998, April 7, 1998, and May 2, 2001)(emphasis added) 3. The’592 Patent The ’592 patent, entitled “Systems and Methods for Electrosurgical Tissue Treatment in Conductive Fluid,” was issued on May 1, 2001 with Philip E. Eggers and Hira V. Thapliyal as inventors. It was originally filed on July 27, 1998 and traces priority to the ’882 patent. Specifically, the ’592 patent is a division of U.S. Patent No. 5,871,469, which is a division of the ’882 patent. The ’592 patent was granted with forty-three claims on May 1, 2001. Claims 1, 3, 4, 11, 21, 23, 26, 27, 32, and 42 are presently asserted and are all method type claims. Claims 3, 4, 11, and 21 depend from claim 1. Claim 26, 27, 32, and 42 depend from claim 23. These claims read as follows: I. A method for applying electrical energy to a target site on a body structure on or within a patient’s body, the method comprising: positioning an electrode terminal into at least close proximity with the target site in the presence of an electrically conductive fluid; positioning a return electrode within the electrically conductive fluid such that the return electrode is not in contact with the body structure to generate a current flow path between the electrode ■ terminal and the return electrode; and applying a high frequency voltage difference between the electrode terminal and the return electrode such that an electrical current flows from the electrode terminal, through the region of the target site, and to the return electrode through the current flow path. 3. The method of claim 1 further comprising immersing the target site within a volume of the electrically conductive fluid and positioning the return electrode within the volume of electrically conductive fluid to generate the current flow path between the electrode terminal and the return electrode. 4. The method of claim 1 further comprising delivering the electrically conductive fluid to the target site. II. The method of claim 1 wherein the electrically conductive fluid comprises isotonic saline. 21. The method of claim 1 wherein the voltage is in the range from 500 to 1400 volts peak to peak. 23. A method for applying electrical energy to a target site on a body structure on or within a patient’s body, the method comprising: contacting an active electrode with the body structure in the presence of an electrically conductive fluid; spacing a return electrode away from the body structure in the presence of the electrically conductive fluid; and applying a high frequency voltage difference between the active electrode and the return electrode such that an electrical current flows from the active electrode, through the electrically conductive fluid, and to the return electrode. 26. The method of claim 23 further comprising immersing the target site within a volume of the electrically conductive fluid and positioning the return electrode within the volume of electrically conductive fluid to generate a current flow path between the active electrode and the return electrode. 27. The method of claim 23 further comprising delivering the electrically conductive fluid to the target site. 32. The method of claim 23 wherein the electrically conductive fluid comprises isotonic saline. 42. The method of claim 23 wherein the voltage is in the range from 500 to 1400 volts peak to peak. (’592 patent, col. 24 at 11. 6-21; 36-32; 64-65; col. 25 at 11. 36-37, 43-54, 61-67; col. 26 at 11. 20-21, 59-60) The court construed disputed terms of the ’592 patent to ascertain both their meaning and scope. (D.I.353) The most significant constructions for the purposes of resolving the parties’ post-trial motions are as follows: 1. The phrase “spacing a return electrode away from the body structure” and “the return electrode is not in contact with the body structure” means that the return electrode is not to contact the body at all during the performance of the claimed method. 2. The term “electrically conducting fluid” and “electrically conductive fluid” shall be construed to mean “any fluid that facilitates the passage of electrical current.” 3. The term “return electrode” shall be construed to mean “an electrode having a larger area of contact than an active electrode, thus affording a lower current density.” (D.I.353) C. The Accused Products Smith & Nephew presently manufactures and sells the Saphyre bipolar ablation probe (“Saphyre”) and the ElectroB-lade Resector (“ElectroBlade”) for use in arthroscopic procedures. These products entered the market in 2002. It also previously manufactured and sold the Dyonics Control RF System (“Control RF”) for use in arthroscopic procedures, but discontinued this product from the market in early 2002. (D.I. 436 at 3) The Saphyre product consists of a stainless steel shaft with a plastic handle and a single large area active electrode at the far or “distal” end of the “shaft.” (D.I. 400 at 3) The inner and outer surfaces of the Saphyre shaft are covered with an insulating coating, except at the distal tip where the active electrode is located. (Id.) A single return electrode clip is attached on top of this insulated shaft. (Id.) The return electrode and insulated shaft are covered with another insulating layer, except for a window located over the return electrode clip near the distal end of the shaft. (Id.) The Saphyre probe is connected to the Smith & Nephew Vulcan Generator. (Id. at 4) The ElectroBlade probe consists of a stainless steel inner tube (i.e., inner blade) and a hollow stainless steel shaft (i.e., outer blade). (Id.) The inner blade slides into the shaft hollow and includes an opening near its distal end. The inner blade rotates within the shaft when connected to a motor drive unit. (Id.) When it passes the edge of the opening in the shaft during rotation, a shearing action results. (Id. at 5) This shearing action serves to resect, or cut, target tissue. In addition to resecting tissue, the inner blade also acts as the active electrode when coagulation power is applied to the probe. (Id.) The return electrode is another hollow, stainless steel tube that runs from a point close to the opening in the shaft to a point in the handle. (Id.) The return electrode is covered with an insulating layer, except for an exposed section near the distal end of the shaft. The ElectroBlade probe does not contain a fluid delivery system. Instead, a separate instrument delivers fluid to the target tissue during an arthroscopic procedure. (Id. at 4) The ElectroBlade probe is connected to the Valleylab Force FX Generator. (Id. at 5) Before being discontinued, the Control RF probe consisted of a stainless steel shaft in a plastic handle with a single active electrode at the far end. (Id. at 6) A return electrode was located near the active electrode at the far end of the shaft. The majority of the shaft was covered with an insulating material, except in the region of the active and return electrodes. (Id.) The Control RF probe did not contain a fluid delivery system; instead, a separate instrument pumped fluid during an arthroscopic surgery to the target tissue. (Id.) The Control RF probe was connected to a Valleylab Force FX Generator via a Dyon-ics Control RF Generator Adaptor. (Id.) D. The Alleged Prior Art Throughout the course of the trial, Smith & Nephew introduced numerous documents in an attempt to establish that the patents in suit were invalid in light of prior art references. These references include four patents and two journal articles as follows: (1) U.S. Patent No. 4,116,-198 (the “’198 patent”); (2) U.S. Patent No. 4,381,007 (the “ ’007 patent”); (3) U.S. Patent No. 4,674,499 (the “ ’499 patent”); (4) U.S. Patent No. 5,122,138 (the “’138 patent”); (5) “Vaporization of Atherosclerotic Plaques by Spark Erosion,” 5 Journal of the American College of Cardiology, No. 6 at 1382-6 (1985) written by Cornelis J. Slager, et. al. (the “Slager article”); and (6) “Uber ein Instrument zur leckstrom-freien transurethralen Resektion,” (translated as “An Instrument for Transurethral Resection Without Leakage of Currents”), 24 Acta Medico Technica, No. 4 at 129-134 (1976) written by Von E. Elsasser and Eberhard. Roos (the “Elsasser/Roos article”). The ’007 and ’499 patents were cited to the PTO during the prosecution of the ’536 and ’882 patents. (See ’536 patent cover; ’882 patent cover) The Elsas-ser/Roos article was also cited during the prosecution of the ’536 patent, and the ’198 patent was cited during the reexamination of the ’536 patent. (See ’198 patent cover; ’198 patent reexamination certifícate) The ’198 patent, entitled “Electro-Surgical Device,” is the most contentious item of prior art raised in the litigation at bar. Eberhard Roos is named as the sole inventor on this patent. In general, it relates to a bipolar electrosurgical device that may be passed through an endoscope. The device consists of a treatment electrode, a neutral electrode, a cable means to connect the treatment electrode to one pole of a high-frequency generator, another means for connecting the neutral electrode to the other pole of the high-frequency generator, and a channel for directing washing liquid to the treatment site. (’198 patent, col. 7 at 11. 45-61) The 198 invention is particularly directed toward electrosurgical operations on the filled bladder. (Id., col. 1 at 11. 18-21) Claim 1 of this patent recites: 1. In combination, an endoscope having an endoscope body of substantially tubular shape, an electrosurgical device comprising a treatment electrode projecting at one end from said endoscope body and a neutral electrode arranged adjacent said treatment electrode, insulated cable means for connecting said treatment electrode to one pole of a high-frequency generator, and means for connecting said neutral electrode to the other pole of a high-frequency generator, said endoscope body having an insulating projection extending over a portion of the periphery of said endoscope body at said one end and having a front edge, said neutral electrode being located within said endoscope body and spaced a distinct distance inwardly from said front edge, a space being formed between said treatment electrode and said neutral electrode which is adapted to be filled with liquid to provide electrical conductance between said electrodes. (Id., col. 7 at 11. 45-62)(emphasis added) The ’007 patent is entitled, “Multipolar Corneal-Shaping Electrode with Flexible Removable Skirt,” and names James D. Doss as the sole inventor. This patent is directed toward a multipolar probe that employs radiofrequency electrical current to heat and thereby induce reshaping of the cornea in mammals. (’007 patent, col. 1 at 11. 10-13) The probe employs a plurality of electrode means that may be connected to the terminal of a radio-frequency source. (Id., col. 6 at 11. 60-61) The ’499 patent is entitled, “Coaxial Bipolar Probe,” and names David S.C. Pao as the sole inventor. It discloses an elec-trosurgical bipolar electrode probe for use in ophthalmic, electrocautery, and electro-coagulation operations. (’499 patent, col. 1 at 11.15-18) The 138 patent is entitled, “Tissue Vaporizing Accessory and Method for an Endoscope,” and names Kim H. Manwaring as the sole inventor. This patent is directed toward radio frequency energized endoscopic tissue dissection, vaporization, and coagulation devices designed for use in conjunction with an endoscope. (138 patent, col. 1 at 11. 7-9; col. 2 at 11. 5-8) These devices may utilize a monopolar RF generator. The Elsasser/Roos article essentially describes using one of the bipolar electrosur-gery devices described in the 198 patent in thirty-two surgeries. In the summary section, this article states that “[t]he high-frequency current ... flows directly from the active cutting electrode, through the tissue to be cut and the irrigation liquid, to the annular neutral electrode at the proximal end of the resectoscope shaft.” (DTX 59-B at 7)(emphasis added) The Slager article describes the in vitro vaporization of fibrous and lipid plaques from segments of atherosclerotic human aortas using an electrical spark generator. (DTX 65) E.The Arthrocare Corp. v. Ethicon, Inc. Decision Arthrocare filed suit against Ethicon, Inc., Mitek Surgical Products, Inc., and Gynecare, Inc. in the Northern District of California on February 13, 1998, alleging infringement of eight claims in four patents. (Arthrocare Corp. v. Ethicon, Inc., No. C-98-0609 WHO (N.D.Cal. Dec. 1, 1998); D.I. 321, ex. A at 1) The claims at issue included: (1) claims 40 and 44 of U.S. Patent No. 5,697,909 (the “ ’909 patent”); (2) claim 45 of the ’536 patent; (3) claim 101 of U.S. Patent No. 5,697, 281 (the “’281 patent”); and (4) claims 1, 26, 28, and 32 of the ’882 patent. (Id. at 2) The case was assigned to Senior Judge William H. Orrick. On March 10, 1998, Arthrocare moved for a preliminary injunction against Ethi-con and Mitek to enjoin the two from making, using, importing, selling, or offering for sale an electrosurgery system marketed and sold under the VAPR System name. (Id.) Judge Orrick issued a memorandum decision on December 1, 1998 denying Arthrocare’s preliminary injunction motion. (Id. at 33) Judge Orrick found substantial questions as to whether: (1) claims 40 and 44 of the ’909 patent and claims 26 and 28 of the ’882 patent are invalid for obviousness in light of the ’198 patent and Elsasser/Roos article; (2) claim 45 of the ’536 patent and claim 101 of the ’281 patent are invalid for anticipation and obviousness in light of the ’198 patent and Elsasser/Roos article; and (3) claims 1 and 32 of the ’882 patent are invalid for lack of enablement. (Id.) The parties settled the litigation in June 1999 prior to trial. F. Procedural History In March 2003, the parties filed multiple motions for partial summary judgment. The court heard oral argument regarding these motions on April 1, 2003 and issued a memorandum opinion and order on April 9, 2003. (D.I.352) The court denied Arth-rocare’s motions for partial summary judgment of infringement of the asserted claims of the ’882 patent and claim 1 of the ’592 patent, denied Smith & Nephew’s motion for summary judgment of nonin-fringement of the asserted claims of the ’882, ’592, and ’536 patents, denied Arthrocare’s motion for partial summary judgment that the patents in suit are not invalid due to obviousness based on an on-sale bar or public use, denied Smith & Nephew’s motion for summary judgment of invalidity based upon prior art, and denied Smith & Nephew’s motion for partial summary judgment of nonenablement, indefiniteness, and lack of written description. (Id.) During the April 1, 2003 oral argument, the court also heard the parties’ positions with respect to the disputed claim language of the patents in suit in accordance with Markman v. Westview Instruments, Inc., 517 U.S. 370, 116 S.Ct. 1384, 134 L.Ed.2d 577 (1996). The court issued a claim construction memorandum order on April 9, 2003. (D.I.353) G. The Trial On April 30, 2003 through May 12, 2003, the parties tried their claims to a jury. The jury found by a preponderance of the evidence that Smith & Nephew directly infringed, induced infringement, and contributed to the infringement of claims 46, 47, and 56 of the ’536 patent with its Saphyre, ElectroBlade, and Control RF products. (D.I.405) The jury also found by clear and convincing evidence that the certificate of correction for claim 1 of the ’882 patent was not invalid and by a preponderance of the evidence that Smith & Nephew induced infringement and contributed to the infringement of claims 13,17, and 54 of the ’882 patent with its Saphyre, Saphyre with Suction, and Control RF products. (Id.) In addition, the jury found by a preponderance of the evidence that Smith & Nephew induced infringement and contributed to the infringement of claims 1, 3, 4, II, 21, 23, 26, 27, 32, and 42 of the ’592 patent with its Saphyre, ElectroBlade, and Control RF products. (Id.) The jury further found that Smith & Nephew did not prove by clear and convincing evidence that the patents in suit are invalid due to anticipation or that claims 13, 17, and 54 of the ’882 patent are invalid for lack of en-ablement. (Id.) The court entered final judgment on June 20, 2003 based upon the jury’s verdict. (D.I.452) III. STANDARD OF REVIEW A. Motion for Judgment as a Matter of Law To prevail on a renewed motion for judgment as a matter of law following a jury trial under Federal Rule of Civil Procedure 50(b), the moving party “ ‘must show that the jury’s findings, presumed or express, are not supported by substantial evidence or, if they were, that the legal conclusions implied [by] the jury’s verdict cannot in law be supported by those findings.’ ” Pannu v. Iolab Corp., 155 F.3d 1344, 1348 (Fed.Cir.1998) (quoting Perkin-Elmer Corp. v. Computervision Corp., 732 F.2d 888, 893 (Fed.Cir.1984)). “ ‘Substantial’ evidence is such relevant evidence from the record taken as a whole as might be acceptable by a reasonable mind as adequate to support the finding under review.” Perkin-Elmer Corp., 732 F.2d at 893. In assessing the sufficiency of the evidence, the court must give the non-moving party, “as [the] verdict winner, the benefit of all logical inferences that could be drawn from the evidence presented, resolve all conflicts in the evidence in his favor, and in general, view the record in the light most favorable to him.” Williamson v. Consol. Rail Corp., 926 F.2d 1344, 1348 (3d Cir.1991); Perkin-Elmer Corp., 732 F.2d at 893. The court may not determine the credibility of the witnesses nor “substitute its choice for that of the jury between conflicting elements of the evidence.” Id. In summary, the court must determine whether the evidence reasonably supports the jury’s verdict. See Dawn Equip. Co. v. Kentucky Farms Inc., 140 F.3d 1009, 1014 (Fed.Cir.1998). B. Motion for a New Trial The decision to grant or deny a new trial is within the sound discretion of the trial court and, unlike the standard for determining judgment as a matter of law, the court need not view the evidence in the light most favorable to the verdict winner. See Allied Chem. Corp. v. Daiflon, Inc., 449 U.S. 33, 36, 101 S.Ct. 188, 66 L.Ed.2d 193 (1980). Federal Rule of Civil Procedure 59(a) provides, in pertinent part: A new trial may be granted to all or any of the parties and on all or part of the issues in an action in which there has been a trial by jury, for any of the reasons for which new trials have heretofore been granted in actions at law in the courts of the United States. New trial are commonly granted in the following situations: (1) where the jury’s verdict is against the clear weight of the evidence, and a new trial must be granted to prevent a miscarriage of justice; (2) where newly-discovered evidence surfaces that would likely alter the outcome of the trial; (3) where improper conduct by an attorney or the court unfairly influenced the verdict; or (4) where the jury’s verdict was facially inconsistent. See Zarow-Smith v. N.J. Transit Rail Operations, 953 F.Supp. 581, 584 (D.N.J.1997) (citations omitted). The court, however, must proceed cautiously and not substitute its own judgment of the facts and assessment of the witnesses’ credibility for the jury’s independent evaluation. Nevertheless, [wjhere a trial is long and complicated and deals with a subject matter not lying within the ordinary knowledge of jurors a verdict should be scrutinized more closely by the trial judge than is necessary where the litigation deals with material which is familiar and simple, the evidence relating to ordinary commercial practices. An example of subject matter unfamiliar to a layman would be a case requiring a jury to pass upon the nature of an alleged newly discovered organic compound in an infringement action. Lind v. Schenley Indus. Inc., 278 F.2d 79, 90-91 (3d Cir.1960). IY. DISCUSSION A. Smith & Nephew’s Renewed Motion for Judgment as a Matter of Law, or in the Alternative a New Trial, on Direct Infringement Grounds 1. The Legal Standard for Direct Infringement A patent is directly infringed when a person “without authority makes, uses or sells any patented invention, within the United States ... during the term of the patent.” 35 U.S.C. § 271(a) (2002). A court should employ a two-step analysis in making a direct infringement determination. See 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). First, the court must construe the asserted claims to ascertain their meaning and scope. See id. Construction of the claims is a question of law subject to de novo review. See Cybor Corp. v. FAS Techs., 138 F.3d 1448, 1454 (Fed.Cir.1998) (en banc). The trier of fact must then compare the properly construed claims with the accused infringing product. See id. This second step is a question of fact. See Bai v. L & L Wings, Inc., 160 F.3d 1350, 1353 (Fed.Cir.1998). Direct infringement occurs where each limitation of at least one claim of the patent is found exactly in the alleged infringer’s product. See Panduit Corp. v. Dennison Mfg. Co., 836 F.2d 1329, 1330 n. 1 (Fed.Cir.1987). The patent owner has the burden of proving direct infringement and must meet its burden by a preponderance of the evidence. See SmithKline Diagnostics, Inc. v. Helena Lab. Corp., 859 F.2d 878, 889 (Fed.Cir.1988) (citations omitted). 2. The’536 Patent Smith & Nephew renews its motion for judgment as a matter of law that its accused products cannot directly infringe independent claim 45 or dependent claims 46, 47, or 56 of the ’536 patent because the probes covered by the ’536 patent must deliver fluid to the target site in light of the court’s claim construction for the term “electrosurgical system.” Smith & Nephew asserts that the probes used in its Saphyre, Control RF, and EleetroBlade products do not introduce such a fluid supply, even though they are used in the presence of electrically conducting fluid. To this end, Smith & Nephew explains that fluid is introduced to the target site by a separate piece of medical equipment like an IV bag or an Intelijet pump and that the separate equipment is not part of the “electrosurgical system.” (D.I. 415 at 976, 1014) Smith & Nephew alleges that Arthroeare’s expert, Dr. Nahum Goldberg, improperly ignored the requirement that an electrically conducting fluid supply be part of the claimed system in his testimony at trial. (See D.I. 411 at 398-99) Accordingly, Smith & Nephew maintains that its products fall outside the scope of the asserted claims in the ’536 patent. The court disagrees. A jury reasonably may have discounted all testimony presented by Smith & Nephew with respect to direct infringement of the ’536 patent after finding Smith & Nephew’s use of the term “electrosurgical system” inconsistent with the court’s claim construction. The court construed this term to mean “an assemblage or combination of things or parts forming a unitary whole.” The court did not require that all elements physically interconnect as implied by Smith & Nephew. Following the court’s construction, the jury likely understood that fluid may be delivered from any source (e.g., the probe itself, an IV bag, or an Intelijet pump) and still permit formation of an “electrosurgical system.” Additionally, there is ample evidence in the record upon which a jury reasonably could have concluded that the accused products meet all limitations of the asserted claims. Dr. Goldberg testified that the accused devices will only function in the presence of electrically conducting fluid. (See id. at 398-99, 405, 412) Smith & Nephew’s own expert, Dr. Kenneth Taylor, also testified that the accused devices require, and will not work without, electrically conducting fluid. (See D.I. 416 at 1453-54) Dr. Taylor likewise admitted that a probe is not required to deliver fluid for the probe and fluid supply to be considered an “electrosurgical system.” (See id. at 1413-16) Moreover, Dr. Taylor explained the components described in the Slager reference comprised an electro-surgical system, even though fluid was not delivered through the probe. (See id. at 1414) Besides direct witness testimony, the jury viewed multiple video clips of the accused products in operation during “normal procedure.” (See PX 105, DTX 315, DTX 316, DTX 897) In all clips, the target sites were submerged under saline fluid. (Id.) The jury further saw product literature from Smith & Nephew, namely the EleetroBlade “Instruction for Use” guide, which described the use of the ElectroB-lade in conjunction with the Intelijet pump and referred to this assembly as the “Recommended System Configuration.” (PX 189 at 3) On the basis of this evidence, a reasonable jury could conclude that the Saphyre, Control RF, and EleetroBlade probes form an “electrosurgical system” as required by the ’536 claims and, as such, infringe the ’536 patent. Accordingly, the court denies Smith & Nephew’s motion for judgment as a matter of law that the ’536 patent is not infringed by the accused products. Concerning a new trial, the verdict is not against the weight of the evidence and no miscarriage of justice will result if the jury’s verdict stands. Smith & Nephew did not present evidence that so overwhelmingly favors its position that the jury clearly erred in finding that the accused products directly infringe the ’536 patent. In addition, the court finds that none of the other reasons for granting a new trial, such as the discovery of new evidence or improper attorney conduct, exist under the facts at bar. Thus, the court denies Smith & Nephew’s motion for a new trial as to literal infringement of the ’536 patent. B. Smith & Nephew’s Renewed Motion for Judgment as a Matter of Law, or in the Alternative a New Trial, Based Upon the Validity of the Certificate of Correction for the ’882 Patent Smith & Nephew argues that its Saphyre, ElectroBlade, and Control RF probes would not directly infringe the ’882 patent but for the certificate of correction that broadened the number of electrodes recited in application claim 23, which became patent claim 1, from four electrodes (i.e., an electrode terminal, an active electrode, a return electrode, and an electrically conducting terminal) to two electrodes (i.e., an electrode terminal and a return electrode). In other words, Smith & Nephew does not contest that its Saphyre, Control RF, and ElectroBlade products directly infringe the asserted claims of the ’882 patent as corrected by the certificate of correction because its accused probes have only two electrodes as recited by the corrected claims. (See D.I. 415 at 1110-1112) Rather, Smith & Nephew argues that the certificate of correction is invalid. In this regard, Smith & Nephew asserts that it was not obtained to correct a mistake, but only to broaden the claims to advance its lawsuit against Ethicon. Additionally, Smith & Nephew argues that, even if the certificate was filed to correct obvious errors, it was not manifest how such corrections should have been made. The court disagrees. The record is replete with evidence upon which a jury reasonably could have found that the certificate of correction was validly made to correct legitimate errors in the claims. Congress enabled a patent applicant to correct errors in a patent due to the applicant’s mistake in 35 U.S.C. § 255. This section provides: Whenever a mistake of a clerical or typographical nature, or of minor character, which was not the fault of the Patent and Trademark Office, appears in a patent and a showing has been made that such mistake occurred in good faith, the Director may, upon payment of the required fee, issue a certificate of correction, if the correction does not involve such changes in the patent as would constitute new matter or would require re-examination. Such patent, together with the certificate, shall have the same effect and operation in law on the trial of actions for causes thereafter arising as if the same had been originally issued in such corrected form. 35 U.S.C. § 255 (2000). This section enumerates two specific kinds of applicant error which may be corrected through a certificate of correction: (1) errors of a clerical or typographical nature; and (2) errors of a minor character. The Federal Circuit has noted that the words of § 255 do not preclude broadening corrections. Superior Fireplace Co. v. The Majestic Prods. Co., 270 F.3d 1358, 1371 (Fed.Cir.2001). However, the Federal Circuit opined that “a broadening correction of a clerical or typographical error [may] be allowed only where it is clearly evident from the specification, drawings, and prosecution history how the error should appropriately be corrected.” Id. at 1373. With regard to mistakes of a minor character, the Federal Circuit has interpreted the language of § 255 to exclude mistakes that broaden a claim. Id. at 1374. The Federal Circuit further has held that the clear and convincing standard is applicable to challenges to the validity of a certificate of correction. Id. at 1367. Applying these principles to the facts at bar, the court notes that Mr. John Raffle, Arthrocare’s in-house counsel, filed an amendment on March 25, 1997 prior to the ’882 patent grant to change the phrase “active electrode” to “electrode terminal.” Mr. Raffle testified that he attempted to make this change for every occurrence of the phrase “active electrode” in the claims. (See D.I. 417 at 1524-26) Mr. Raffle also testified that the phrase “the active electrode” in uncorrected application claim 23 lacked antecedent basis because the precise words “an active electrode” did not appear earlier in the claim set. (See id. at 1515-16) Based upon this testimony, the jury could have inferred that Mr. Raffle inadvertently overlooked two occurrences of the phrase “active electrode” in his amendment and that reference to “the active electrode” after the phrase “an electrode terminal” was a typographical error. A jury likewise reasonably could have concluded that both the typographical error and the proper way to correct it were evident in light of the prosecution history of the ’882 patent. Accordingly, the court denies Smith & Nephew’s motion for judgment as a matter of law that the certificate of correction is invalid. With respect to a new trial, the weight of the evidence does not warrant a new trial to avoid a miscarriage of justice. Arthrocare offered sufficient evidence upon which a jury could have found that the certificate ' of correction is valid. Hence, the court denies Smith & Nephew’s motion for a new trial premised on the invalidity of the certificate of correction for the ’882 patent. C. Smith & Nephew’s Renewed Motion for Judgment as a Matter of Law, or in the Alternative a New Trial, on Contributory and Inducing Infringement Grounds 1. The Legal Standard for Contributory Infringement The doctrine of contributory infringement is codified at 35 U.S.C. § 271(c): Whoever offers to sell or sells within the United States or imports into the United States a component of a patented machine, manufacture, combination or composition, or a material or apparatus for use in practicing a patented process, constituting a material part of the invention, knowing the same to be especially made or especially adapted for use in an infringement of such patent, and not a staple article or commodity of commerce suitable for substantial noninfringing use, shall be liable as a contributory infringer. The Federal Circuit has explained that this form of infringement is premised on the idea that a defendant who displays sufficient culpability should be held liable as an infringer, even though he did not technically make, use, or sell a patented invention. Hewlett-Packard Co. v. Bausch & Lomb, Inc., 909 F.2d 1464, 1469 (Fed.Cir.1990). The Federal Circuit also has noted that “[s]uch liability was under a theory of joint tortfeasance, wherein one who intentionally caused, or aided and abetted, the commission of a tort by another was jointly and severally liable with the primary tortfeasor.” Id. Based upon the language of § 271(c), there can be no con-tributary infringement in the absence of direct infringement. See Aro Mfg. Co. v. Convertible Top Replacement Co., 365 U.S. 336, 341-42, 81 S.Ct. 599, 5 L.Ed.2d 592 (1961). In addition, there can be no contributory infringement without knowledge that the component made or sold was especially adapted for a particular use proscribed by a known patent. See Hewlett-Packard Co., 909 F.2d at 1469. Actual intent to cause or contribute to infringement is not necessary to establish contributory infringement. Id. Instead, “[a] seller of a ‘material part’ of a patented item may be a contributory infringer if he makes a non-staple article that he knows was ‘especially made or especially adapted for use in an infringement of such patent.’ ” Husky Injection Molding Sys. v. R & D Tool & Eng’g Co., 291 F.3d 780, 784 (Fed.Cir.2002) (citing 35 U.S.C. § 271(c); Dawson Chem. Co. v. Rohm & Haas Co., 448 U.S. 176, 219, 100 S.Ct. 2601, 65 L.Ed.2d 696 (1980)). Furthermore, the “occasional and aberrant use of these products, [even] where they are clearly designed to be used in a system specified in the claims of a patent, does not rise to the level of ‘a staple article or commodity of commerce suitable for substantial non-infringing use.’ ” Preemption Devices v. Minnesota Mining & Mfg. Co., 630 F.Supp. 463, 471 (E.D.Pa.1985) (citing Dennison Mfg. Co. v. Ben Clements & Sons, Inc., 467 F.Supp. 391, 428 (S.D.N.Y.1979)). 2. The Legal Standard for Inducing Infringement Pursuant to 35 U.S.C. § 271(b), “[wjhoever actively induces infringement of a patent shall be liable as an infringer.” As with contributory infringement, direct infringement is a prerequisite to inducing infringement. Met-Coil Sys. Corp. v. Komers Unlimited, Inc., 803 F.2d 684, 687 (Fed.Cir.1986). Additionally, the alleged infringer must have knowingly induced infringement. Manville Sales Corp. v. Paramount Sys., Inc., 917 F.2d 544, 553 (Fed.Cir.1990) (citing Water Techs. Corp. v. Calco, Ltd., 850 F.2d 660, 668 (Fed.Cir.1988)). The Federal Circuit has stated that “although section 271(b) does not use the word ‘knowing’, the case law and legislative history uniformly assert such a requirement.” Water Techs., 850 F.2d at 668. In this regard, mere knowledge of the acts alleged to constitute inducement is not enough. Manville Sales Corp., 917 F.2d at 553. Rather, the plaintiff has the burden of showing that “the alleged infringér’s actions induced infringing acts and. that he knew or should have known his actions would induce actual infringements.” Id. 3. The Direct Infringement Prerequisite for Contributory and Inducing Infringement Considering the direct infringement prerequisite for the acts of contributory and inducing infringement, Smith & Nephew argues that the Saphyre, Control RF, and ElectroBlade probes do not practice the limitations of asserted claims of the ’592 patent. Specifically, Smith & Nephew contends that the return electrodes on its products frequently contact target tissue during the performance of the method for applying electrical energy recited in claims 1 and 23 of the ’592 patent. Claim 1 requires “positioning a return electrode ... such that [it] is not in contact with the body structure,” and claim 23 requires “spacing a return electrode away from the body structure.” (’592 patent, col. 24 at 11. 13-14; col. 25 at 11. 48) Smith & Nephew alleges that Dr. Goldberg improperly applied a temporal limitation in testifying that the “only way not to infringe this claim with the device is to make sure that the return electrode ... is always in contact when the energy is on.” (D.I. 411 at 421-22)(emphasis added) Smith & Nephew particularly notes that the return electrodes on its products contact tissue while the probe is being positioned before energy is applied (i.e., during the second step enumerated in claims 1 and 23). Smith & Nephew, therefore, advocates that a reasonable jury could not find that the use of any of its accused products satisfies the return electrode “not in contact/spaced away” limitations given this contact time. (See D.I. 354 at 7) Viewing the record in a light most favorable to Arthrocare as the non-moving party, the court disagrees with Smith & Nephew’s argument. The record reflects that there are times when the return electrode is not in contact with target tissue and all of the other claim limitations are performed, thereby supporting the jury verdict of literal infringement. To this end, Smith & Nephew’s expert, Dr. Michael Choti, admitted that when the active electrode on the Control RF probe is positioned near the target site and energy is applied, the return electrode does not always contact tissue. (See D.I. 412 at 743-744) Ms. Karen Drucker, the ElectroBlade project manager, and Ms. Kate Knudsens, the Saphyre project manager, similarly acknowledged that video clips of the accused products in operation show times when the return electrodes of the ElectroBlade and Saphyre probes, respectively, were not in contact with tissue while energy was applied. (See D.I. 415 at 1036, 985) Mr. Warren Heim, Smith & Nephew’s consultant, also testified that the Control RF probe was designed so that the return electrode would not contact tissue during use. (See D.I. 414 at 957-58) Additionally, Mr. Joe McCreary, the Saphyre marketing manager, testified that the Saphyre can function even if the return electrode is not in contact with tissue. (See D.I. 412 at 555) Moreover, the Saphyre Sales Guide warns that “care should be taken to prevent tissue contact with the return electrode on the Saphyre probe shaft.” (PX 390 at 37) The ElectroBlade Sales Training CD likewise instructs users to “ensure that the entire tip including the return electrode is immersed in saline”, to “present” the active electrode to the tissue, and “to use suction to pull bleeding tissue to the blade for coagulation.” (PX 199 at 11, 7) The Control RF “Instructions for Use” further informs doctors to be sure that the active and return electrodes are “completely surrounded” by electrically conducting fluid during use.” (PTX 205 at 1) Considering the totality of this evidence, a jury reasonably could have found that Smith & Nephew’s accused products meet the “not in contact/spaeed away” limitations of the asserted claims and thereby directly infringe the ’592 patent. 4. Contributory Infringement Smith & Nephew asserts that its products have “substantial non-infringing uses” such that they were not designed to infringe the asserted claims of the patents in suit. Specifically, Smith & Nephew claims that these non-infringing uses include: (1) operation of the probes to apply energy while the return electrode touches tissue (i.e., noninfringement of the ’592 patent); (2) operation of the probes to apply energy without creating a vapor layer, thereby achieving coagulation instead of ablation (i.e., noninfringement of the ’882 patent); and (3) operation of the probes as part of an “eleetrosurgical system” that does not have a fluid supply (i.e., noninfringement of the ’536 patent). The court is again unpersuaded by these arguments. The evidence of record for the ’592 patent discussed above shows that the Saphyre, ElectroBlade, and Control RF probes were constructed to prevent the return electrode from contacting tissue. The court finds that similar evidence exists with respect to the ’882 and ’536 patents. In particular, Smith & Nephew refers to its Saphyre product line as “ablation” probes in its sales guides. (See PX 381 at 1, PX 390 at 10). Smith & Nephew also markets its Saphyre and Control RF probes for use in ablation, not coagulation, even though both may provide coagulation. (See PX 390 at 4, PX 593 at 11, 29, PX 205 at 1) Additionally, several witnesses at trial testified that the Saphyre, ElectroBlade, and Control RF probes must be used with electrically conducting fluid. (See D.I. 411 at 397-98, 405, 412; D.I. 414 at 848; D.I. 415 at 1013) More specifically, Mr. Sparks and Ms. Drucker testified that electrically conducting fluid must be delivered to the target site in arthroscopic surgery. (See D.I. at 814-16; D.I. 415 at 1013-14) A reasonable juror, taking all of this evidence into account, could have concluded that the accused probes were designed to infringe and that the occasional or aberrant use of one of them in a non-infringing manner, as suggested by Smith & Nephew, does not constitute a substantial nonin-fringing use. Therefore, the court denies Smith & Nephew’s motion for judgment as a matter of law that it is not liable for contributing to the infringement of the patents in suit. As to a new trial, none of the reasons for granting a new trial exists in the instant case. That is, the jury’s verdict is not against the weight of the evidence. Rather, both sides presented evidence to support their respective positions. Additionally, no miscarriage of justice will result by upholding the jury’s verdict. For these reasons, the court denies Smith & Nephew’s motion for a new trial on contributory infringement grounds. 5. Inducing Infringement Smith & Nephew argues that it is not liable as an inducing infringer because Arthrocare failed to prove that Smith & Nephew intends to cause its customers to infringe the asserted claims of the patents in suit. The court finds that Smith & Nephew’s arguments are not well founded and that sufficient evidence exists in the record to support the jury’s verdict of inducing infringement. In particular, Ms. Knudsen and Mr. Heim testified that they read the patents in suit before the Saphyre probe design was complete and prior to design efforts commenced for the ElectroBlade and Control RF probes. (D.I. 415 at 991; D.I. 414 at 936-37, PX 735 at 23-25) They further stated that they evaluated Arthrocare’s patented products prior to designing the accused products. (D.I. 414 at 951, D.I. 415 at 977-78) On this basis, a jury reasonably could have found that Smith & Nephew knew or should have known that its customers would directly infringe the patents in suit when using the Saphyre, ElectroBlade, and Control RF probes. Consequently, the court denies Smith & Nephew’s motion for judgment as a matter of law that it is not liable for inducing infringement. Regarding a new trial, the jury’s verdict of inducing infringement is not against the clear weight of the evidence. Moreover, no miscarriage of justice will result if this verdict stands. Accordingly, the court concludes that a new trial is not warranted and denies Smith & Nephew’s motion for a new trial on inducing infringement grounds. D. Smith & Nephew’s Renewed Motion for Judgment as a Matter of Law, or in the Alternative a New Trial, on Invalidity Grounds Smith & Nephew renewed its motion for judgment as a matter of law that the patents in suit are invalid based on prior art grounds. Before reaching the substance of this motion, Arthrocare challenges Smith & Nephew’s right to raise this motion claiming that Smith & Nephew failed to preserve the issue of invalidity before the case was submitted to the jury pursuant to Fed.R.Civ.P. 50(a). Rule 50(b) permits consideration of such renewed motions for judgment as a matter of law only when a motion for a directed verdict has been made at the close of the evidence offered by an opponent. In pertinent part, Rule 50(b) states: If, for any reason, the court does not grant a motion for judgment as a matter of law made at the close of all the evidence, the court is considered to have submitted the action to the jury subject to the court’s later deciding the legal questions raised by the motion. The movant may renew its request for judgment as a matter of law by filing a motion no later than 10 days after entry of judgment. Rule 50(a) requires that “[a] motion for a directed verdict shall state the specific grounds therefor.” This requirement is in place to afford the non-moving party with the opportunity to reopen its case and present additional evidence. See Bonjorno v. Kaiser Aluminum & Chem. Corp., 752 F.2d 802, 814 (3d Cir.1984)(citing Lowenstein v. Pepsi-Cola Bottling Co., 536 F.2d 9, 11 (3d Cir.1976)). In the case at bar, Smith & Nephew motioned for a directed verdict three times. It first made a Rule 50(a) motion at the close of Arthrocare’s case. (See D.I. 415 at 1161) It made a second Rule 50(a) motion at the close of all the evidence. (See D.I. 417 at 1549) Smith & Nephew then renewed this motion prior to the jury charge. (See D.I. 418 at 1700) Since the issue of invalidity had not been presented when Smith & Nephew initially moved for a directed verdict, the court finds that Smith & Nephew’s first motion was not directed to the invalidity of the patents in suit. The court notes, however, that the issue of invalidity was in evidence at the time Smith & Nephew made its second and third motions. The court also notes that it indicated after these latter motions that Smith & Nephew’s rights were reserved, despite the fact that Smith & Nephew did not specifically state the precise grounds for its motions. (See D.I. 417 at 1549; D.I. 418 at 1700). As well, the court did not require any argument concerning the motions when raised and precluded Smith & Nephew from discussing them. The court, therefore, concludes that it would be unjust to Smith & Nephew not to consider its renewed motion for judgment as a matter of law. Accordingly, the court will consider the instant motion. 1. The Legal Standard for Invalidity A patent is presumed valid, and each claim whether in independent, dependent, or multiple dependent form is presumed to be valid independent of the validity of other claims. 35 U.S.C. § 282 (2003). The party asserting invalidity, consequently, has the burden of proof. Id. This burden is satisfied only by proving facts establishing invalidity by clear and convincing evidence. Geneva Pharms., Inc. v. Glaxosmithkline Plc, 349 F.3d 1373, 1377 (Fed.Cir.2003) (citing Applied Materials, Inc. v. Advanced Semiconductor Materials Am., Inc., 98 F.3d 1563, 1569 (Fed.Cir.1996)). The patentee, therefore, need not submit any evidence to support the validity of a patent. Orthokinetics, Inc. v. Safety Travel Chairs, Inc., 806 F.2d 1565, 1570 (Fed.Cir.1986). Moreover, the challenger’s burden is especially difficult to meet when the art relied on at trial was considered by the PTO. BOC Health Care, Inc. v. Nellcor, Inc., 892 F.Supp. 598, 602 (D.Del.1995). Indeed, the Federal Circuit has stated: When no prior art other than that which was considered by the PTO examiner is relied on by the attacker, he has the added burden of overcoming the deference that is due to a qualified government agency presumed to have properly done its job, which includes one or more examiners who are assumed to have some expertise in interpreting the references and to be familiar from their work with the level of skill in the art and whose duty it is to issue only valid patents. American Hoist & Derrick Co. v. Sowa & Sons, Inc., 725 F.2d 1350, 1359 (Fed.Cir.1984). a. Invalidity on Anticipation Grounds A patent is invalid for anticipation under 35 U.S.C. § 102 if a single prior art reference explicitly discloses each and every limitation of the claimed invention. Lewmar Marine, Inc. v. Barient, Inc., 827 F.2d 744, 747 (Fed.Cir.1987). The Federal Circuit has stated that “[t]here must be no difference between the claimed invention and the reference disclosure, as viewed by a person of ordinary skill in the field of the invention.” Scripps Clinic & Research Found. v. Genentech, Inc., 927 F.2d 1565, 1576 (Fed.Cir.1991). In determining whether a patented invention is explicitly anticipated, the claims are read in the context of the patent specification in which they arise and in which the invention is described. Glaverbel Societe Anonyme v. Northlake Mktg. & Supply, Inc., 45 F.3d 1550, 1554 (Fed.Cir.1995). The prosecution history and the prior art may be consulted if needed to impart clarity or to avoid ambiguity in ascertaining whether the invention is novel or was previously known in the art. Id. A prior art reference also may anticipate without explicitly disclosing a feature of the claimed invention if that missing characteristic is inherently present in the single anticipating reference. Continental Can Co. v. Monsanto Co., 948 F.2d 1264, 1268 (Fed.Cir.1991). The Federal