Full opinion text
OPINION AND ORDER CRABB, District Judge. In this civil action, plaintiff Briggs & Stratton Corp. accuses defendant Kohler Co. of manufacturing and selling a single-cylinder internal combustion engine that infringes claims 1-2, 4, 6-11 and 13 of plaintiffs United States Patent No. 6,382,-166 (the ’166 patent) and claims 1, 2-6, 8, 11-13 and 15-31 of United States Patent No. 6,460,502 (the ’502 patent). Plaintiff seeks declaratory, injunctive and monetary relief under 35 U.S.C. § 271. Defendant asserts six counterclaims, alleging non-infringement, patent invalidity and violations of 15 U.S.C. §§ 1 & 2 of the Sherman Act, Wisconsin antitrust laws, Wis. Stat. §§ 133.03, 133.04, 133.14 and 133.18 and the Wisconsin common law of unfair competition. The case is before the court on plaintiffs motions to strike and for summary judgment on the issues of literal infringement and validity and on defendant’s motion for partial summary judgment limiting damages. Jurisdiction is present. 28 U.S.C. §§ 1338(a) and 1331. Before setting out the undisputed facts, I will address plaintiffs motion to strike portions of the brief and supporting declarations defendant filed in response to plaintiffs motion for summary judgment. I. MOTION TO STRIKE On February 16, 2005, plaintiff served its first set of interrogatories and requests for production on defendant. Interrogatory # 1 asked defendant to [e]xplain in detail, on a claim-by-claim and limitation-by-limitation basis, each of KOHLER’S contentions that any claim of the T66 PATENT or the ’502 PATENT is invalid, void, and/or unenforceable under 35 U.S.C. §§ 101, 102, 103, and 112, including an identification of documents that KOHLER contends support such contentions, the complete legal and factual bases for such contentions, including claim construction contentions, and each person having knowledge of any factual basis. Aff. of Joseph T. Miotke, dkt. #81, exh. # 2, at 1. Defendant responded on March 24, 2005. On May 26, 2005, and again on August 9, 2005, defendant supplemented its responses to plaintiffs first set of interrogatories and requests for production. On July 15, 2005, defendant’s expert, James Brogdon, filed an expert report that included Brogdon’s claim constructions and opinions regarding the invalidity of the ’166 and ’502 patents. On August 4, 2005, defendant filed a second report by Brogdon in response to the report filed by plaintiffs expert, Marthinius van Schoor. Plaintiff contends that these filings were incomplete and that defendant has included in its brief in response to the motion for summary judgment expert opinions and legal arguments that were not disclosed previously to plaintiff, in violation of Fed.R.Civ.P. 26(e)(1). Plaintiff objects to (A) defendant’s new non-infringement argument based on its assertion that the Courage balance system used in defendant’s allegedly infringing engine does not have a counterbalance weight disposed on the second side of the crankshaft; (B) the allegedly new proposed constructions of the terms “counterbalance weight,” “rail,” “adapter,” “runner filler,” “selectable,” and “substantially uniform”; and (C) numerous statements and documentary evidence offered by defendant’s expert, James Grondin, and by defendant’s Rule 30(b)(6) witness, Terrence Rotter. This evidence includes new claims regarding the obviousness of the T66 patent, allegedly contradictory testimony regarding the design of the Courage engine, testimony discussing “types” of runner fillers, two allegedly inaccurate summary charts and new references to prior art. Plaintiff asks that all arguments and materials not previously disclosed by defendant be stricken under Fed. Rule Civ. P. 37(c)(1) or under the “sham affidavit doctrine.” Rule 26(e) of the Federal Rules of Civil Procedure places upon litigants a duty to supplement “the information contained in [an expert witness’s] report” and “information provided through deposition of the expert” if the party learns that the information previously disclosed was incomplete or incorrect in any material respect. Rule 26(e)(1). Rule 26(e)(2) requires litigants to “seasonably amend” prior responses to interrogatories when a party learns that its earlier responses were incomplete or incorrect in any material respect. A party who fails to disclose information required by Rule 26(e)(1) or to amend a prior response to discovery as required by Rule 26(e)(2) is not permitted to use the undisclosed evidence at trial, at a hearing or on a motion unless the failure is harmless or substantially justified. Fed.R.Civ.P. 37(c)(1). “The determination of whether a Rule 26(a) violation is justified or harmless is entrusted to the broad discretion of the district court.” Mid-America Tablewares, Inc. v. Mogi Trading Co., Ltd., 100 F.3d 1353, 1363 (7th Cir.1996). A. Defendant’s Non-Infringement Argument Regarding the ’166 Patent Relying on the declaration of its expert, James Brogdon, defendant argues that its Courage series engine does not utilize a counterbalance weight disposed on the second side of the engine’s crankshaft. Defendant asserts that its new position is the logical response to the opinion expressed by plaintiffs expert, Marthinus van Schoor, in his August 5, 2005 invalidity report that the Menen (U.S. Patent No. 4,407,169) counterbalance weight is not disposed on the second side of the crankshaft. The Menen counterbalance weight is “virtually identical” to the Courage counterbalance weight; therefore, defendant argues, if Menen does not have a counterbalance weight disposed on a second side of the crankshaft, neither does the Courage series engine. Although this may be a logical position, it was not disclosed prior to the filing of defendant’s response to plaintiffs motion for summary judgment. Defendant argues that the non-disclosure was justified because it did not have “an opportunity to respond” to van Schoor’s report before filing its response to plaintiffs motion for summary judgment and it had no way of knowing from van Schoor’s July 13, 2005 report on infringement that van Schoor viewed the Menen patent in this way. Defendant’s argument is dubious in two respects. First, Magistrate Judge Crock-er advised the parties on March 7, 2005, to: ... undertake discovery in a manner that allows them to make or respond to dispositive motions within the scheduled deadlines. The fact that the general discovery cutoff ... occurs after the deadlines for filing and briefing disposi-tive motions is not a ground for requesting an extension of the motion and briefing deadlines. Order dated Mar. 7, 2005, dkt. # 10, at 3. Despite that admonition, defendant did not schedule a deposition of van Schoor, plaintiffs expert, until September 1, 2005, two weeks after the court’s extended summary judgment deadline and seven weeks after defendant had received van Schoor’s report on infringement, in which van Schoor gave his opinion that the Courage balance system was disposed on a second side of the crankshaft. Second, although defendant argues that after it learned on August 5, 2005, of van Schoor’s position on the Menen patent, it had no opportunity to amend its infringement position, the facts show otherwise. Defendant supplemented its response to interrogatories on August 9, 2005, four days after receiving the report from van Schoor with specific reference to the Men-en patent and six days before the deadline for summary judgment. Defendant’s supplemental answers does not include its new position that the ’166 patent did not infringe claim 1 because it does not have a counterbalance weight disposed on a second side of the crankshaft. When Rule 26 is violated, exclusion of any non-disclosed information is “automatic and mandatory unless the sanctioned party can show that its violation of Rule 26 was either justified or harmless.” David v. Caterpillar, Inc., 324 F.3d 851, 857 (7th Cir.2003). It is difficult to imagine how nondisclosure of an infringement defense in a patent infringement case could be harmless or how the non-disclosure could be justified under the circumstances of this case. Therefore, I will grant plaintiffs request and will disregard any reference to defendant’s claim that the Courage series engine’s counterbalance weight is not disposed on the second side of the crankshaft. B. Changes in Proposed Claim Constniction The table below shows defendant’s new proposed constructions for six terms at issue in the ’166 and ’502 patents. Table I Term Construction asserted as of August 9, 2005_ Proposed construction for summary judgment_ counterbalance weight a weight that counters forces associated with movement of a piston a weight that counters forces associated with movement of a piston that is not integral or rigidly fixed to the crankshaft rail a bar with at least two substantially perpendicular surfaces that is fixed to one structure extending longitudinally upon which another structure is slidable and which serves to direct the motion of that structure along the axis of the bar a bar with at least two substantially perpendicular surfaces that is fixed to one structure extending longitudinally upon which another structure is slidable and which serves to direct the motion of that structure along the axis of the bar adapter a device that permits the cylinder head’s intake position to be altered a device used to connect different pieces of apparatus runner filler a component that is positioned within, and fully defines at least part of, the intake passageway a part of the adapter that is disposed within the intake runner that at least partially forms the intake passageway_ selectable capable of being altered capable of being chosen or picked out substantially uniform varying only slightly from uniformity_ largely or approximately uniform Plaintiff reads defendant’s brief as implying that defendant construes the term rail to include a requirement that the counterbalance weight “interface with corresponding slots or recesses” on the rail. Although in his declaration Brogdon states that the 166 patent requires interfacing, the construction of “rail” proposed in defendant’s response brief is identical to the construction previously disclosed to plaintiff. I will not read defendant’s proposed claim construction any more narrowly than it is framed in the response brief. For that reason, the propriety of the non-existent “change” in construction need not be addressed. Similarly, defendant’s changed construction of “substantially uniform” is insignificant. I see no difference in meaning between defendant’s originally proposed construction of the term “substantially uniform” as “varying only slightly from uniformity” and its new construction, “largely or approximately uniform.” If an object varies slightly from uniformity, then it is largely uniform. The remaining changes in defendant’s claim constructions are substantial. Defendant excuses the late changes in two ways. First, it asserts that its new construction of the term “adapter” was simply a response to plaintiff’s new construction of the term in its brief in support of its motion for summary judgment. Although plaintiff denies this contention, the record supports defendant. In a responsive report filed on August 15, 2005, plaintiffs expert, Dr. van Schoor, wrote that “one of ordinary skill in the art would construe the term ‘adapter’ to be a component that is used to effect operative compatibility between different parts of a system.” Am’d Rep. of Dr. van Schoor, dkt. # 53, exh. # 26, at 11. Plaintiff contends in its summary judgment brief that an “adapter” is “a device that permits the cylinder head’s intake position to be altered.” Plt.’s Brief in Supp. of M. for Summ. J. on ’502 patent, dkt. # 50, at 14. Despite plaintiffs arguments to the contrary, this is a new construction of the term adapter. It would be unreasonable to permit plaintiff to introduce a new claim construction in its motion for summary judgment and then prohibit defendant from responding with a new construction of its own. Therefore, I will consider both parties’ proposed constructions for the term “adapter” as defined in their summary judgment briefs. Second, defendant argues that its remaining changes in the construction of the terms “counterbalance weight,” “runner filler” and “selectable” are excusable because they were made in response to van Schoor’s amended expert report, filed by plaintiff on August 15, 2005. Defendant does not explain why it waited to disclose these new claim constructions to plaintiff in its response brief instead of including them in its amended replies to interrogatories, which it filed four days after receiving van Schoor’s amended report. Because defendant has provided no justifiable excuse for its failure to provide plaintiff with notice of its new claim constructions prior to responding to plaintiffs motion for summary judgment, I will not consider the new constructions proposed in defendant’s response brief. Rather, I will rely on the claim constructions disclosed to plaintiff as of August 9, 2005, as shown in Table 1, above. C. Statements and Opinions of Defendant’s Experts 1. Opinions related to obviousness of the ’166 patent Plaintiffs third objection to defendant’s summary judgment arguments focuses on defendant’s submission of a chart created by its expert, Brogdon, that compares each claim of the ’166 patent to numerous pieces of prior art. See Brog-don Deck, dkt. # 65, exh. E. According to plaintiff, Brogdon’s readings of prior art as reflected in Exhibit E differ from his reading of the prior art as disclosed in his expert report. Although plaintiff is correct in stating that Brogdon’s positions in his expert report differ slightly from positions taken in the summary chart attached to his declaration in support of defendant’s response brief, all but one of the changes are minor. In Exhibit E, Brogdon withdraws his contention that Van Ligten and Menen each contain a counterbalance weight disposed on a second side of the crankshaft, and amends his prior contention that use of a rail interconnected with the counterbalance weight or crankcase housing as described in claim 1 is rendered obvious by Kollock, Ricardo, Murata, Shirai and Ljun-strom under defendant’s construction and asserts that the use of a rail is obvious under both parties’ constructions. None of these changes prejudice plaintiff in any way and may in fact bolster its case. Plaintiff concedes this, stating that defendant’s changed readings of Kollock, Ricardo, Murata, Shirai and Ljunstrom “constitute an admission by Kohler that these five references cannot anticipate claim 1 under either party’s construction.” Accordingly, I will deny plaintiffs request to strike these minor changes. However, one difference between Brog-don’s expert report and the summary chart merits further attention. In the summary chart, defendant contends for the first time that claims 7 and 8 are rendered obvious by Ljunstrom under both parties’ proposed constructions. This reading of Ljunstrom is entirely new and was not disclosed to plaintiff. Therefore, I will not consider it. 2. “New” opinions related to the ’502 patent Plaintiff objects to defendant’s submission of a second chart created by Brogdon that compares each claim of the ’502 patent to numerous pieces of prior art. Brog-don Decl., dkt. # 70, exh. B. According to plaintiff, defendant has changed its reading of prior art pieces from the reading Brogdon provided in his expert report. In addition, plaintiff objects to the inclusion of “new opinions” in ¶¶ 7, 9,11,12,14-17, 21-28, 30-32 and 34 of Brogdon’s declaration in support of defendant’s response brief. a. Summary chart Although plaintiff contends that the table attached to Brogdon’s declaration in support of defendant’s response brief as Exhibit B contains “literally dozens of new opinions,” Plt.’s Br. on M. to Strike, dkt. #80, at 18, plaintiff limits its attack to three examples: (1) a new reference to the Howarth engineering text; (2) a claim that Watanabe anticipates claim 22 instead of rendering it obvious; and (3) “new combinations of references render obvious many of the claims.” Id. Rather than sorting through which of the many alleged discrepancies between Brogdon’s report and his chart are legitimate and which are not, I will not consult Exhibit B in deciding plaintiffs motion, but will rely instead on Brogdon’s affidavit, declaration and expert report to support defendant’s proposed findings of fact regarding prior art relating to the ’502 patent. I will deny plaintiffs motion as moot with respect to the exhibit. b. Motivation to combine Plaintiff objects to “new” references to inventors’ motivation to combine prior art references found in defendant’s response brief and in Brogdon’s declaration in support of defendant’s response brief. Plaintiff does not contend that the prior art references upon which defendant relies were undisclosed, but rather that defendant did not disclose its argument that inventors would have been motivated to combine the references, thereby rendering obvious the ’502 patent. Defendant offers no explanation for its failure to disclose its “motivation to combine” arguments to plaintiff at an earlier date. Generally, failure to disclose amended expert opinions is sufficient reason to strike new arguments. However, as the moving party, plaintiff bears the burden of showing which of defendant’s arguments are new and which were disclosed prior to summary judgment. Plaintiff has not provided this information. Defendant has made over 200 arguments regarding the invalidity of the ’502 patent. The parties do not suggest that all of these arguments were undisclosed. Therefore, absent specific information indicating which arguments ought to be stricken and which should stand, I will deny plaintiffs motion to strike any of defendant’s arguments regarding inventors’ motivation to combine prior art. c.Statements regarding the structure of the Courage series engine At his deposition, Rotter declared that the counterbalance weight used in the Courage engine was designed as “one piece.” Rotter Dep., dkt. # 41, at 153, In. 25. When questioned about the portion of the piece that plaintiff contends is a link arm, Rotter testified that its purpose was to “connect ... the crankshaft to the mass you want to move.” Id. at 154, In. 10-11. In his declaration in support of defendant’s response brief, Rotter states that “the counterbalance weight of the Courage engine fits over the crankshaft and does not utilize link arms.” Rotter Deck, dkt. # 71, at ¶ 14. Plaintiff asserts two grounds for striking the statements found in Rotter’s declaration. First, the statements disclose information that bolsters defendant’s previously undisclosed non-infringement argument that the Courage engine’s counterbalance weight is not disposed on a second side of the crankshaft and second, they contradict Brogdon and Rotter’s deposition testimony and are therefore “sham affidavits.” I have already indicated that I will not consider defendant’s previously undisclosed argument that the Courage engine’s counterbalance weight is not disposed on a second side of the crankshaft. It is unnecessary to strike Rotter’s statements on the ground that they might support his now-stricken argument. Plaintiff argues in the alternative that the statements should be stricken under the “sham affidavit doctrine.” The Court of Appeals for the Seventh Circuit has long held that parties cannot thwart the purposes of Rule 56 by creating “sham” issues of fact with affidavits that contradict prior deposition testimony. Bank of Illinois v. Allied Signal Safety Restraint Systems, 75 F.3d 1162, 1168 (7th Cir.1996). It is settled law that if a party submits affidavits or declarations after a deposition that recant or modify deposition testimony, the court can ignore the affidavits in the absence of a convincing explanation for the change in testimony, such as a failure to understand the question completely or the discovery of new evidence. Id. at 1170. However, the court will not exclude post-deposition evidence unless the statements are inherently inconsistent and any contradiction is not the result of an honest discrepancy or newly discovered evidence. Id. Although plaintiff argues that the declaration of Rotter is a “sham affidavit” that conflicts with his prior deposition testimony, I conclude that the declarations are not inherently inconsistent. At his deposition, Rotter was asked about the function of the top and bottom portions of the one-piece counterbalance weight used in the Courage engine. In the context of that question, Rotter made a distinction between the “mass” and the connecting pieces. However, by admitting that the weight contained connectors, Rotter was not necessarily admitting the weight had link arms, as he understood the term. If Rotter believed link arms were connectors formed separately from the counterbalance weight itself (as defendant implies throughout its response brief), he might reasonably deny that the one-piece weight used in the Courage engine has link arms. The potential discrepancies between Rotter’s deposition testimony and declaration may provide fodder for later impeachment, but they are not inherently contradictory. Therefore, I will deny plaintiffs motion to strike the declaration. d. Types of runner fillers In defendant’s brief in response to plaintiffs motion for summary judgment, it discusses “runner fillers” and describes them as coming in two varieties: open and closed. Plaintiff objects to this characterization, contending that it is a “new opinion” previously undisclosed by defendant that must be stricken. The assertion that runner fillers can be open (meaning not fully enclosed) or closed is not an expert opinion, but rather a factual observation. Moreover, as defendant emphasizes, it is a fact that plaintiff does not contest. Because defendant did not violate Rule 26 by failing to “disclose” its classification of runner fillers, I will deny plaintiffs motion with respect to this request. e. Reference to Howarth engineering text Plaintiff objects to all references to the Howarth engineering text made by Brog-don in his declaration in support of defendant’s response brief. Plaintiff alleges that this text was not clearly disclosed and that Brogdoris opinions regarding the text are new and unanticipated. In his declaration supporting defendant’s response brief, Brogdon states for the first time that the Howarth engineering textbook shows a “closed runner filler” similar to the runner filler taught by the ’502 patent. Defendant says that plaintiff was on notice that Brogdon would rely on Howarth because it provided plaintiff a copy of portions of the text prior to Brogdon’s deposition. However, nowhere in his report or in his deposition testimony did Brogdon refer to Howarth or state that it contained a “closed runner filler” similar to the runner filler taught by the ’502 patent. It was not enough for defendant to provide plaintiff a copy of portions of the textbook in advance of Brogdoris deposition if Brogdon was not relying explicitly on the textbook in his expert report and deposition testimony. Howarth purportedly shows a “closed runner filler” similar to the one taught by the ’502 patent. If anything, the fact that defendant’s expert reviewed the patent and made no comment on it in his report or deposition would have reasonably led plaintiff to conclude that Howarth did not call into question the validity of the ’502 patent. Therefore, because defendant failed to make a timely disclosure of Brogdoris opinion that Ho-warth invalidates the ’502 patent, I will grant plaintiffs motion and will disregard any reference to the Howarth text. II. PLAINTIFF’S MOTION FOR SUMMARY JUDGMENT Turning next to plaintiffs motion for summary judgment, I note that large portions of defendant’s submissions regarding the ’166 patent do not comply with this court’s procedures regarding summary judgment. Those procedures required the party responding to the motion for summary judgment to answer each of the mov-ant’s proposed findings of fact, supporting disputed facts with citations to admissible evidence. Procedures to be Followed on Motions for Summary Judgment I.C.l. To support a proposed fact, parties may rely upon depositions, answers to interrogatories, admissions pursuant to Fed.R.Civ.P. 36, other admissions, affidavits and authenticated documents. Procedures I.C.l.a-f. In its response to plaintiffs proposed findings, defendant consistently omitted citations or cited broadly to its brief, which is not an admissible source of evidence. Id. Where defendant has failed to comply with the court’s procedures, its disputes have been disregarded. Procedures II.C. (“Unless the party opposing the motion puts into dispute a fact proposed by the moving party, the court will conclude that the fact is undisputed.”). See also Metropolitan Life Ins. Co. v. Johnson, 297 F.3d 558, 562 (7th Cir.2002) (court of appeals has “consistently and repeatedly upheld a district court’s discretion to require strict compliance with its local rules governing summary judgment”). In addition, defendant has attempted to supplement its proposed findings with broad references to exhibits and reports, under the apparent assumption that the court will consider all facts alleged in those exhibits and reports to be proposed facts. The court’s procedures require that each fact be proposed in a separate paragraph in the proposed findings of fact. Procedures I.B.1. Where defendant has cited exhibits as “facts” (see, for example, DPFOF for the ’502 patent, dkt. # 88, ¶ 35), its proposals have been disregarded. Propositions contained in briefs that were not the subject of proposed findings of fact have not been considered. Procedures I.B4. From the parties’ proposed findings of fact, I find the following facts to be undisputed. A. Undisputed Facts 1. Parties Plaintiff Briggs & Stratton Corporation is incorporated under the laws of the state of Wisconsin and has its primary place of business in Wauwatosa, Wisconsin. Defendant Kohler Company is incorporated under the laws of the state of Wisconsin and has its primary place of business in Kohler, Wisconsin. Defendant does substantial business in the state of Wisconsin. Both plaintiff and defendant manufacture internal combustion engines. These engines are commonly used in outdoor power equipment, such as lawn mowers and lawn tractors. Plaintiff has had success in the marketplace with its engines, such as the Intek with Anti-Vibration System (an embodiment of plaintiffs ’166 patent). 2. The’166 patent a. Counterweights and counterbalance weights Most internal combustion engines produce mechanical power by converting the up and down motion of a piston into rotary motion. The piston is attached to a crankshaft by means of a rod. As the piston moves, the crankshaft rotates. The rotary motion of the crankshaft can be harnessed for a wide variety of uses. In all piston engines, as the piston moves up and down in a cylinder bore, it accelerates and decelerates. These accelerations and decelerations produce an equal and opposite force. The motion of the piston generates inertia forces that can be modeled as forces having various frequencies. The most significant of these forces are referred to as primary and secondary force components. The primary force component is at the same frequency as the crankshaft rotation. The secondary component is at twice the rotation frequency- As a piston engine operates, the forces reacting to the piston’s acceleration forces are transmitted to the engine main bearings and from the bearings to the structure of the engine. In a simple cylinder engine, these forces are transmitted to the equipment on which the engine is mounted and are felt as vibrations. Vibrations are undesirable because they can be unpleasant to operators of machinery and because they can cause damage to the engine and to attached, equipment. For more than a century, engineers have been designing mechanisms for reducing these undesirable vibrations. One early method of reducing transmission vibrations involved the use of a counterweight, which can balance linear (primary) acceleration forces on the axis of a piston, when attached to the engine crankshaft and rotating with it. However, because counterweights rotate with the crankshaft, they cannot reduce secondary inertia forces. Counterweights introduce unwanted side-to-side vibrations and therefore can only partially balance forces associated with piston movement. They are unable to provide dynamic balance and they reduce vibrations caused by piston reciprocation by only 50-60%. A more effective solution to engine vibration is the counterbalance weight, which is a mass equal to the piston mechanism’s reciprocating mass. The center of gravity of a counterbalance weight moves the same distance and along the same line of motion as the piston mechanism’s center of gravity, but in a direction opposite that of the piston with which it is aligned. Counterbalance weights provide an equal and opposite force to the piston mechanism’s acceleration that cancels the acceleration-induced forces of the piston. Typically, counterbalance weights do not rotate. A counterbalance weight can cancel both the primary forces and a significant portion of the secondary forces associated with piston reciprocation. As a result, counterbalance weights are able to provide engines with significant dynamic balance that counterweights cannot provide; counterbalance weights can cancel 80-90% of the forces created by a reciprocating piston. Counterbalance weights and reciprocating counterbalance weights were used in engine manufacturing long before the invention claimed in the ’166 patent was conceived. In 1876, Nicolaus Otto invented the first practical gasoline internal combustion engine. His engine balanced piston acceleration by using a mass that moved in linear opposition to the piston. In May 1924, a magazine titled The Motor featured an article describing a counterbalance mechanism in which a “single crank... carries an eccentric at each side of the throw.” The article explained, “These eccentrics cause weights to move up and down in opposition to the pistons, the weights being guided upon steel pegs which are fixed to the sump of the engine.” (The parties have not explained the meaning of the term “eccentric.” The New Oxford American Dictionary defines it as “a disc or wheel mounted eccentrically on a revolving shaft in order to transform rotation into backward-and-forward motion.” New Oxford American Dictionary 538 (2001).) Many other ways of counterbalancing piston inertia forces have been employed. One of the simplest of these is balancing one piston with another. In a horizontally opposed configuration, a second cylinder is deployed opposite the first cylinder and the crankshaft is arranged to move the pistons in opposition to one another. In the most economical of these horizontally opposed configurations, the two cylinders are not directly in line but are close enough to one another that the large shaking force of a single cylinder is reduced to a small turning torque. In horizontally opposed engines with six cylinders, even this small turning torque can be eliminated. Another form of balancing one piston with another is seen in the common automotive engine configurations of four and six cylinders. In a four cylinder engine, the inertia forces that shake the engine are completely balanced by having two pistons going up while two others are going down. In a six cylinder engine, the balancing of up and down forces is not as evident but the balance is complete. b. Prosecution of the T66 patent On May 7, 2002, United States Patent No. 6,382,166 (the ’166 patent) was issued to Daniel L. Klika and John H. Thiermann for an invention entitled “Balancing System Using Reciprocating Counterbalance Weight.” By virtue of assignment, Briggs & Stratton has acquired and continues to maintain all rights, title and interests in and to the 166 patent. Claim 1 of the 166 patent reads as follows: 1. A balancing system for an internal combustion engine having a crankcase housing and a cylinder bore defining a cylinder axis, the system comprising: a crankshaft substantially within the crankcase housing, wherein the cylinder bore is disposed on a first side of the crankshaft; a piston disposed in the cylinder bore for reciprocal movement generally along the cylinder axis in response to rotation of the crankshaft; a counterbalance weight disposed on a second side of the crankshaft that is generally opposite the first side, said counterbalance weight reciprocating in response to rotation of the crankshaft; and a rail interconnected with at least one of said counterbalance weight and said crankcase housing such that said rail guides said counterbalance weight during reciprocation of said counterbalance weight. ’166 patent, col. 4., Ins. 6-24. Claims 2, 4, 6-11 and 13 depend from claim 1. They read as follows: 2. The system of claim 1, further comprising a link arm coupling the counterbalance weight to the crankshaft. 4. The system of claim 2, further comprising an eccentric portion of the crankshaft, wherein the link arm engages the eccentric portion. 6. The system of claim 1, further comprising two spaced link arms coupling the counterbalance weight to the crankshaft. 7. The system of claim 1, further comprising a second rail interconnected with at least one of the counterbalance weight and the crankcase housing that guides said counterbalance weight. 8. The system of claim 7, further comprising a third rail interconnected with at least one of the counterbalance weight and the crankcase housing that guides said counterbalance weight. 9. The system of claim 1, wherein the rail is substantially parallel to the cylinder axis. 10. The system of claim 1, wherein the other of said counterbalance weight and said crankcase housing has a slot that receives said rail. 11.The system of claim 1, further comprising a guide surface that engages said counterbalance weight. 13. The system of claim 1, wherein the mass of said counterbalance weight is equally distributed on opposite sides of said cylinder axis. Id. at col. 4, Ins. 25-26, 30-32, 36-53, 56-58. The ’166 patent discloses a counterbalance weight system that reciprocates in response to piston movement to reduce vibration. The figure shown below corresponds to Figure 1 of the T66 patent and shows one embodiment of the balancing system. The interior of the single cylinder engine has a crankshaft (10) located in a crankcase housing (12). The counterbalance weight (26) is disposed on one side of the crankshaft and is connected to the crankshaft (10) using two link arms (22 and 24). The piston (not shown) is located on the other side of the crankshaft and the counterbalance weight reciprocates in opposition to the piston’s reciprocation. The motion of the counterbalance weight is directed by one or more rails interconnected with either the crankcase housing or the counterbalance weight. The rails between the counterbalance weight and the crankcase housing can be seen in the figure below (Figure 4 of the 166 patent). It provides a cross-sectional view of the counterbalance weight (26), showing three rails (40, 34 and 42) interconnected with the crankcase housing (not numbered). In this particular embodiment of the 166 patent, the rail (34) is inserted into a slot (32) positioned on the side of the counterbalance weight. Other embodiments may either eliminate the centrally disposed rail (34), leaving rails (40 & 42) to direct the counterbalance weight’s motion, or use a single rail (34) with a corresponding slot. The 166 patent discloses using a combination of rails and guides. The difference between a rail and a guide is illustrated in the figure above and the figure shown below (Figure 9 of the 166 patent). The figure above is a cross-sectional view showing a centrally disposed rail (50) and two guides (54 and 56) interconnected with the crankcase housing (48). The rail is inserted into a slot (58) positioned on the side of the counterbalance weight (46) and directs the motion of the counterbalance weight. The guides have flat upper surfaces that prevent the counterbalance weight from rocking to either side during reciprocation. If the center slot on the counterbalance weight in the figure above is removed, the counterbalance weight is free to move left or right because the guides restrict only downward motion. The guides are unable to direct the counterbalance weight along the guides’ axes. By contrast, the center rail (50) guides the counterbalance weight along the plane defined by the rail’s two side surfaces. The application for the 166 patent disclosed a number of patents to the United States Patent and Trademark Office, including United States Patent No. 350,068 (the Louque patent), United States Patent No. 4,407,169 (the Menen patent), United States Patent No. 4,656,981 (the Murata patent) and United States Patent No. 5,927,242 (the Kollock patent). Initially, the Patent and Trademark Office rejected claims 1-13 of the 166 patent pursuant to 35 U.S.C. § 102(b) as anticipated by the Louque patent. Issued in 1886, the Louque patent discloses a balancing system for a steam engine having the cylinder bore and the counterbalance weight on the same side of the crankshaft, where the weight is guided by a rail, as shown in Figure 1 of the Louque patent, reproduced below. The guide rails (S), which are parallel to the piston’s axis and mounted on the engine frame, connect to slots in the counterbalance masses so that the crankshaft (C) and connecting rod (P) drive the counterbalance masses in straight-line motion opposite the motion of the piston. The Lou-que patent does not disclose a cylinder bore and weight disposed on opposite sides of the crankshaft. Before the Patent and Trademark Office, plaintiff argued that the Louque patent requires relatively large amounts, of space and is not feasible for modern internal combustion engines because it places the cylinder bore and weight on the same side of the crankshaft. In the Louque patent, the center of gravity is high and the engine is relatively unstable. Plaintiff amended the preamble to claim 1 of the T 66 patent, changing “a balancing system for an engine” to “a balancing system for an internal combustion engine.” In addition, plaintiff argued that claim 4 of the ’166 patent required a link arm connecting the counterbalance weight to an eccentric on the crankshaft, whereas the Louque patent did not disclose eccentrics. Ultimately, the Patent and Trademark Office allowed claims 1-13. Approximately one year after filing the ’166 patent application, plaintiff filed a Patent and Trademark international patent application. Claims 1-13 of that application were identical to claims 1-13 of the ’166 patent. The European Patent Office performed an international search and issued an initial report indicating that claims 1, 2, 7 and 9-13 were considered to lack novelty or an “inventive step” in view of United States Patent No. 5,927,242 (the Kollock patent) and a British patent, GB 249,693 (the Austin patent). When patents and printed publications are the primary source of prior art for both United States domestic applications and “PCT” international applications, the “PCT”- uses novelty and obviousness standards similar to those used under the law of the United States. In response to the “PCT” ’s initial report, plaintiff filed a demand for preliminary examination. The United States Patent and Trademark Office was selected as the international preliminary examining authority charged with preparing an international preliminary examination report. The Patent and Trademark Office reviewed the cited patents and issued a report concluding that claims 1-13 “met the criteria set out in PTC Article 33(2)-(4) because the prior art d[id] not teach or fairly suggest a rail interconnected with a counterbalance weight and crankcase housing,” and that “[industrial applicability as defined by PTC Article 33(4) is [met] by the invention reducing vibration in reciprocating internal combustion engines.” c. The Courage engine In 2000, as a competitive response to plaintiffs Intek engine, defendant began developing a new engine. Defendant determined that it needed a new single cylinder engine of up to twenty horsepower and a counterbalance weight system to address the vibration caused by piston reciprocation. In designing the new engine, one of defendant’s goals was to reduce vibration to levels lower than those of plaintiffs Intek engine. Defendant named its new engine the Courage engine. At the time defendant began developing the Courage engine, plaintiffs Intek engine did not utilize the balance system claimed in the ’166 patent, which plaintiff later marketed as the Anti-Vibration System, or AVS. Defendant did not become aware of plaintiffs AVS system until summer 2001, when defendant’s representatives saw a sample of the system in an Intek engine at a trade show. The Courage engine is a single cylinder engine that employs a mass to balance inertia forces generated by the piston assembly and a portion of the connecting rod assembly. This mass is a counterbalance weight. (Defendant’s engineers sometimes refer to the counterbalance weight as a “flying brick.”) The counterbalance weight is composed of two identical halves linked together by a pin inserted through the bottom center of the weight. The pin remains parallel to the cylinder axis during reciprocation. The counterbalance weight moves back and forth in response to the rotation of the crankshaft. The mass of the engine’s counterbalance weight is distributed on opposite sides of the cylinder axis. It is connected to an eccentric on the crankshaft. The counterbalance weight in the Courage engine is disposed on a second side of the crankshaft opposite the cylinder bore and is connected to the crankshaft. As the piston moves up, the counterbalance weight is lowered below the piston. As the piston moves down, the counterbalance weight is raised below the piston. During operation, the counterbalance weight moves in the opposite direction of the reciprocating piston. Because the connecting portion of the weight is fixed, the counterbalance weight experiences a “wobbling” or “waggling” motion in addition to the linear motion toward or away from the crankshaft. To guide the planar motion of its counterbalance weight, the Courage engine uses a bearing that fits between two raised ribs formed integrally with the crankcase housing. Defendant refers to this bearing surface as a “guide shoe.” The metal guide shoe is affixed to one end of the counterbalance weight by a pin and can pivot around the pin’s axis. The guide shoe fits into a groove in the crankcase housing created by two raised ribs that extend outward from the crankcase. The ribs are parallel to the cylinder axis and guide the planar motion of the counterbalance weight along the ribs’ central axis. The ribs form an elongated recess in the space between them. This space receives the guide shoe and guides the motion of the counterbalance weight along its axis as it moves back and forth within the slot in opposition to the reciprocating piston. As the guide shoe moves, the ribs extending from the closure plate do not touch the counterbalance weight. The pin is loosely placed in the guide shoe. As the counterbalance weight moves back and forth, the pin and the counterbalance weight pivot, causing the weight to “waggle.” As the weight waggles, the sides of the guide shoe are not in contact with both ribs at the same time. Instead, the guide shoe moves back and forth in the space between the ribs, never touching both ribs at the same time. There is always empty space between the guide shoe and the back wall created by the two ribs. This “waggling” of the guide shoe causes the counterbalance weight to move across the cylinder axis unequally distributing the counterbalance weight on each side of the cylinder axis. The “waggling” does not affect the ability of the Courage engine to dynamically balance the forces caused by piston reciprocation. Defendant applied for a patent on the balance system used in the Courage engine. The patent issued on April 5, 2005 as United States Patent No. 6,974,458. d. Prior art Defendant’s expert, James Brogdon, identifies numerous patents that he contends anticipate the ’166 patent or render its claims obvious: the Louque, Austin, Murata, Kollock, Menen, Fiala, Ogura, Ricardo, Van Ligten and Shirai patents. (The Louque patent is discussed above in reference to the prosecution history of the ’166 patent.) (1) The Austin patent The Austin patent is directed to inline non-opposing multiple cylinder engines and discloses a method for using bob weights to balance the secondary inertia forces associated with a reciprocating piston. The primary vibrations of in-line non-opposing multiple cylinder engines are naturally balanced. The figure below (Figure 1 of the ’693 patent) shows how the primary inertia forces of the two outside pistons are cancelled by the primary forces generated by the middle pistons. The bob weight (D) is attached to an eccentric and guided by rails (E) that move the weight in the same direction as the piston. Bob weights cannot be applied to single piston engines and cannot be applied to engines with an uneven number of cylinders unless the weights exceed the mass of the piston they are designed to balance. The Patent and Trademark Office considered the Austin patent during plaintiffs international patent application and issued a report concluding that “the prior art does not teach or fairly suggest a rail interconnected with the counterbalance weight and crankcase housing.” (2) The Murata patent During the prosecution of the T66 patent, the U.S. Patent Office considered U.S. Patent No. 4,656,981 (the Murata patent). (Figure 2 of the Murata patent) The Murata patent discloses an engine that uses a guide pin (15) to guide the motion of its counterbalance weight (11) generally along an axis parallel to the piston’s axis. The guide pin is cantilevered from the crankcase housing and interfaces with a hole (14) in the counterbalance weight. The guide pin cannot direct the planar motion of the counterbalance weight along the axis of the guide pin. Thus, the counterbalance weight could rotate around the guide pin. However, a sidewall engages a stop (16) secured to the crankcase (1) to prevent the weight from rotating (15). The Murata patent does not teach the use of a rail as recited in claim 1 of the 166 patent. (3) The Kollock patent The Kollock patent discloses a balancing system that, like the system disclosed in the Murata patent, uses a guide pin supported on both ends or a cantilevered pin secured to the housing to guide the counterbalance weight, which is not equally distributed on opposite sides of the cylinder axis. (Figure 1 of the Kollock patent) The weight is free to rotate around the guide pin. The Kollock patent does not teach or suggest the use of link arms to connect the balance weight with the crankshaft or the use of a rail as recited in claim 1 of the ’166 patent. (4) The Menen patent The Menen patent discloses a crankshaft (44) with two weights (55) mounted in “slideways” (67). (Figure 8 of the Menen patent) The reciprocating weights surround the crankshaft. A second portion of each weight is disposed on one side of the crankshaft and is supported by the first portion. The first and second portions are configured so that more of the mass of the counterbalance weight is located in the second portion. The weights in the Menen patent can balance only the primary forces stemming from piston reciprocation. They cannot reduce or eliminate the secondary inertia forces of piston reciprocation. The Menen patent discloses the use of slideways. These slideways may be lubricated rails that provide side and sliding support for the bearing surfaces (68 and 69). The patent provides no detail about the geometry or construction of these slideways. The weights in the Menen patent are not disposed on a second side of a crankshaft that is generally opposite the first side. The crankshaft runs through the weights. The Menen patent does not teach the use of a slot or link arms. (5) The Fiala patent German patent DE 3033803 (the Fiala patent) is directed to sectioned engines. Engines are sectioned to allow sections of cylinders to be turned off when their power is not needed (in slow traffic, for example). As reflected in the figure below (Figure 1 of the Fiala patent), the invention provides a kinematic depiction of a straight line guidance (27) of the weight (26). (6) The Ogura patent Japanese patent JP61-206844 (the Ogu-ra patent) discloses a gourd shaped link arm (12), as shown in Figure 1 of the patent, that enables the use of heavier counterbalance masses and smaller eccentrics to provide dynamic balance for the reciprocating movement of the piston. (7) The Ricardo patent United States Patent No. 1,342,648 (the Ricardo patent) discloses a balancing mechanism for balancing out the secondary component of the inertia forces stemming from the reciprocating movement of the piston. As reflected in the figure below (Figure 10 of the Ricardo patent), one embodiment of the Ricardo patent uses a guide pin (L) to guide the motion of weight (A). The weight balances only the secondary inertia forces of the piston and leaves the primary component of the inertia forces unchanged. The guide pin (not shown) is not a rail. (8) The Van Ligten patent United States Patent No. 4,819,592 (the Van Ligten patent) discloses a balancing mechanism having a preferred embodiment with a weight or mass (25) guided by a pah- of leaf springs (41 and 42) with the crankshaft (3) going through the center of the mass. The figure above shows the crankshaft (3) running through the weight. The weight (25) balances only the secondary inertia forces of the piston and leaves the primary component of the inertia forces unchanged. The Van Ligten patent does not disclose a bar that directs the planar motion of a counterbalance weight substantially along its axis. The Van Ligten patent does not specify that the weight is equally distributed on opposite sides of the cylinder axis. (9) The Shirai patent Japanese patent JP 3-67738 (the Shirai patent) discloses a guide pin used to guide the motion of a counterbalance weight. The Shirai patent does not disclose how rotation of the counterbalance weight is avoided. It does not disclose a bar or relief that directs the planar motion of the weight substantially along its axis. 3. The ’502 Patent a. Background In a conventional internal combustion engine, a carburetor mixes air and fuel delivered through a cylinder head to the cylinder chamber. In the cylinder chamber, the air-fuel mixture is ignited by a spark plug. The energy generated by the ignition drives the motion of the piston. Although the carburetor is sometimes connected directly to the cylinder head, for decades engineers have utilized spacers, inserts, ports and other similar devices to connect the carburetor to the cylinder head and direct the air-fuel mixture from the carburetor into the cylinder head. Companies that manufacture lawn mowers or lawn tractors do not also manufacture the products’ engines. Equipment manufacturers differ in their requirements for location and placement of engines within their products. Costs increase substantially when manufacturers have to redesign engines to fit the space available in a variety of devices, such as lawn mowers and lawn tractors. For this reason, it is desirable for engine manufacturers to have a flexible engine design and a manufacturing method that can be modified easily to make engines that can be used in a variety of existing devices. When an equipment manufacturer selects an engine, one important consideration is the location of certain engine parts, such as the engine’s intake position, mounting brackets and drive shaft. An engine may not be compatible with a particular manufacturer’s lawn mower because existing features of the lawn mower interfere with parts of the engine; for example, there may not be enough room for a carburetor and fuel tank near an engine’s intake position. A manufacturer can incur great expense relocating the intake runner from one position to another to accommodate different carburetor locations in different equipment manufacturer’s products because the relocation requires redesigning the cylinder head and related tooling. The invention claimed by the ’502 patent permits an engine’s intake position to be altered without having to redesign the entire engine. A cylinder head incorporating the new invention can be connected to a carburetor that would otherwise be at a different elevation from the intake passageway. Therefore, the engine can be used on a wider variety of vehicles. b. Prosecution of the ’502 patent The inventions disclosed in the ’502 patent were conceived no later than May 2, 2000 and were reduced to practice in June 2000. On October 8, 2002, United States Patent No. 6,460,502 (the ’502 patent) was issued to Gary Gracyalny for an invention entitled “Engine Cylinder Head Assembly.” By virtue of assignment, Briggs & Stratton acquired and continues to maintain all rights, title and interests in and to the ’502 patent. The Patent and Trademark Office issued the ’502 patent after considering United States Patent No. 3,442,805 (Dzianott), United States Patent No. 3,832,702 (Roberts), United States Patent No. 4,336,777 (Yanagihara), United States Patent No. 6,006,721 (Shannon) and Russian Patent No. RU 2013626 (Kukha-rev). The Patent and Trademark Office originally rejected independent claim 1 of the ’502 patent as anticipated or obvious in view of United States Patent No. 6,026,774 (Kajihara). The Patent and Trademark Office indicated that dependent claims 2 and 4 “would be allowable” if rewritten in independent form. In response, plaintiff amended claim 1 to include the permissible subject matter of claim 2 and added what issued as claims 15-31. The Patent and Trademark Office then permitted claims 1-31. Claim 1 of the ’502 patent reads as follows: 1. A cylinder head assembly for an internal combustion engine comprising: an intake port; an intake runner that receives at least one of air and fuel, said intake runner including: an entrance; a section having a first end nearer said entrance and having a second end nearer said intake port; an adapter having a runner filler disposed within said intake runner; an intake passageway having a substantially uniform cross-sectional area created at least in part by said runner filler; and wherein the cross-sectional area of said intake runner decreases from said entrance to said intake port. ’502 patent, col. 6, In. 54—col. 7, In. 2. Claims 2-6, 8 and 11-13 depend from claim 1. They read as follows: 2. A cylinder head assembly according to claim 1, wherein said intake runner includes: an inclined surface with a semi-circular cross-section; and a straight surface with the shape of an interior surface of a segmented cylinder. 3. A cylinder head assembly according to claim 1, wherein said runner filler has a contact surface with the shape of an exterior surface of a segmented cylinder. 4. A cylinder head assembly according to claim 1, wherein said intake passageway is formed by said section and said runner filler. 5. A cylinder head assembly according to claim 1, wherein said entrance is elliptical in shape. 6. A cylinder head assembly according to claim 1, wherein said entrance has a[h]eight dimension and a width dimension, said height dimension being greater than said width dimension. 8. A cylinder head assembly according to claim 6, wherein a line including said height dimension is substantially parallel to a longitudinal axis of a piston cylinder. 11. A cylinder head assembly according to claim 1, wherein said cylinder head assembly includes a cylinder head, and said adapter thermally insulates a carburetor from said cylinder head. 12. A cylinder head assembly according to claim 11, wherein said adapter has a spacer that thermally insulates a carburetor from said cylinder head. 13. A cylinder head assembly according to claim 1, wherein said adapter has a substantially cylindrical inlet. ’502 patent, col. 7, Ins. 3-19, 23-25, 32-41. Claim 15 of the ’502 patent reads as follows: 15. A cylinder head assembly for an internal combustion engine comprising: an intake port; an intake runner that receives at least one of air and fuel, said intake runner including: an entrance; a section having a first end nearer said entrance and having a second end nearer said intake port; an adapter having a runner filler positioned in said intake runner; and an intake passageway disposed within said intake runner and at least partially defined by said runner filler, wherein the position of said intake passageway is selectable based upon at least one of the position and the configuration of said runner filler. ’502 patent, col. 7, Ins. 44-59. Claims 16-21 depend from Claim 15, and read as follows: 16. The cylinder head assembly of claim 15, wherein said intake passageway has a substantially uniform cross-sectional area. 17. The cylinder head assembly of claim 15, wherein the cross-sectional area of said intake runner decreases from said entrance to said intake port. 18. The cylinder head assembly of claim 15, wherein said entrance is substantially elliptical in shape. 19. The cylinder head assembly of claim 15, wherein said cylinder head assembly includes a cylinder head, and wherein said adapter thermally insulates a carburetor from said cylinder head. 20. The cylinder head assembly of claim 19, wherein said adapter includes a spacer that thermally insulates said carburetor from said cylinder head. 21. The cylinder head assembly of claim 15, wherein said adapter includes a substantially cylindrical adapter inlet. ’502 patent, col. 8, Ins. 1-17. Claim 22 of the ’502 patent reads as follows: 22. A cylinder head assembly for an internal combustion engine comprising: an intake port; an intake runner that receives at least one of air and fuel, said intake runner including an entrance having a height dimension than a width dimension of said entrance; an adapter having an inlet and having a runner filler positioned in said intake runner; and an intake passageway at least partially defined by said runner filler, said passageway extending from an inlet near said entrance, wherein the position of said inlet is selectable along said height dimension. ’502 patent, col. 8, Ins. 18-30 Claims 23-31 depend from claim 22, and read as follows: 23. The cylinder head assembly of claim 22, wherein the cross-sectional area of said intake runner decreases from said entrance to said intake port. 24. The cylinder head assembly of claim 22, wherein said intake passageway has a substantially uniform cross-sectional area. 25. The cylinder head assembly of claim 22, wherein the cross-sectional area of said intake passageway is less than the cross-sectional area of said intake runner. 26. The cylinder head assembly of claim 22, wherein the cross-sectional area of said inlet is less than the cross-sectional area of said entrance. 27. The cylinder head assembly of claim 22, wherein said entrance is substantially elliptical in shape. 28. The cylinder head assembly of claim 22, wherein said cylinder head assembly includes a cylinder head, and said adapter thermally insulates said carburetor from said cylinder head. 29. The cylinder head assembly of claim 27, wherein said adapter includes a spacer that thermally insulates said carburetor from said cylinder head. 30. The cylinder head assembly of claim 26, wherein said adapter incl