Full opinion text
FINDINGS OF FACTS AND CONCLUSIONS OF LAW ZOBEL, District Judge. Table of Contents I. Introduction.112 II. Background of the Case.112 A. Ariad’s Invention .112 B. Obtaining Allowance.113 C. Lilly’s Drugs.114 D. Commencement of Litigation.114 E. The Jury Trial.114 F. Post-Verdict Motions.115 G. The Bench Trial.115 III. Discussion.116 A. Validity of the Patent Under 35 U.S.C. § 101.116 1. Exceptions to Patentable Processes.116 2. The Autoregulatory Loop Theorizes a Reduction in NF-kB Activity.117 a. Support for the Existence of the Autoregulatory Loop.118 b. Testimony of Ariad’s Expert, Dr. Ravetch .119 c. Cross-Examination of Dr. Latchman.120 d. There Is Insufficient Evidence to Invalidate the Patent.120 B. Inequitable Conduct During Prosecution of the '516 Patent.120 1. The Legal Standard for Inequitable Conduct.121 a. Materiality.121 b. Intent.122 2. The Allegedly Withheld Information.122 a. Errors in Figure 43.122 b. References Showing Inherent Anticipation.123 3. The Materiality of the Errors and Omissions in Figure 43 .123 a. The Description of Figure 43 Is Incorrect.123 b. Figure 43 Is Incomplete.124 c. Figure 43 Is Material Despite Its Late Addition to the Application.125 d. Figure 43 Is Not Cumulative.125 e. The Errors in Figure 43 Are Material Under Both Standards.126 4. The Materiality of the Prior Art References.127 a. The Cited References Are Not Cumulative.128 b. Recognition Requirement for Inherent Anticipation.130 5. Evidence of Intent Concerning the Errors in Figure 43.131 a. The Prosecuting Firm and Attorney History of the '516 Patent.131 b. Evidence of Intent by Hausdorff.133 e.Evidence of Intent by Vincent.133 d. Evidence of Intent by Clauss.134 (1) Clauss’ Testimony on Materiality.134 (2) Clauss’ Response to Office Action.134 6. Evidence of Inventor Baldwin’s Intent to Conceal References.135 C. Lilly’s Prosecution Laches Defense.136 1. The Legal Standard for a Finding of Prosecution Laches.136 2. Analysis of Delays in the Prosecution of the '516 Patent.137 a. Requirement to File an Appeal.137 b. Six Month Response to Office Actions.138 c. The Pre-'898 Applications.138 d. Post Development Applications.138 (1) Prejudice to Public Rights.139 e. Use of Transitional Rules.139 IV. Conclusion.140 I. Introduction Plaintiffs Ariad Pharmaceuticals, Inc., Massachusetts Institute of Technology, the Whitehead Institute for Biomedical Research, and the President and Fellows of Harvard College (collectively “Ariad”), owners and assignees of U.S. Patent No. 6,410,516 (“the '516 patent”), “Nuclear Factors Associated With Transcriptional Regulation,” complain that defendant Eli Lilly & Co. (“Lilly”) infringed it. Following a fourteen-day trial in April 2006, a jury found that the four asserted claims were valid against anticipation, enablement and written description defenses, and that use of Lilly’s Evista and Xigris products infringed the patent. The jury awarded plaintiffs damages in excess of $65 million. The parties agreed that certain additional defenses were to be tried to the court. Lilly asserts that the '516 patent is invalid because it attempts to claim non-patentable subject matter under 35 U.S.C. § 101. Even if the patent is valid, Lilly argues (1) that it cannot be enforced because of inequitable conduct by plaintiffs during the prosecution of the patent, or in the alternative; (2) that plaintiffs are estopped from recovering for any infringement because they unreasonably delayed prosecution of the patent. Following a second trial focused on these issues, I find that: (1) the four claims asserted are patentable; (2) Lilly has not proven inequitable conduct during patent prosecution; and (3) Ariad did not unreasonably delay prosecution of the '516 patent. Accordingly, the jury award stands. II. Background of the Case A. Ariad’s Invention In the mid-1980s, scientists at the Massachusetts Institute of Technology, the Whitehead Institute for Biomedical Research, and Harvard University (“plaintiff institutions”) identified a protein called Nuclear Factor Kappa B (“NF-kB”). Present in the cytoplasm of many different cell types, NF-kB is what is known as a transcription factor, a protein that affects gene expression. In the inactive state, NF-kB binds in the cytoplasm with another protein, Inhibitor Kappa B (“IkB”), to form a multi-protein complex. When NF-RB is activated by various stimuli external to the cell, the complex dissociates and free NF-kB is released. This free NF-kB then travels into the cell nucleus and binds there to specific DNA sequences, causing the cell to produce proteins that are associated with many diseases, including cancer, AIDS, sepsis, and atherosclerosis. Inhibiting this process has enormous and wide-ranging therapeutic effects. The inventors filed a patent application on their invention. After a sixteen year trek through the United States Patent and Trademark Office (the “PTO”) littered with abandoned, divisional and continued applications, they were granted the '516 patent on June 25, 2002. Throughout much of the prosecution history of the '516 patent, questions concerning enablement under 35 U.S.C. § 112 delayed allowance, in many instances because the claims called for the use of an “agent” or “substance” to effect a reduction or alteration in the level of NF-kB activity in the cell. The PTO repeatedly rejected these claims because it said that the specification did not adequately describe all possible agents or substances encompassed by the claims. B. Obtaining Allowance On August 10, 2000, the primary examiner of the '516 application, Dr. Robert Schwartzman (“Schwartzman”), rejected all but one claim of the pending application as not adequately describing the agents used in claims drawn to methods requiring “an agent which has an effect on ... NF-RB and/or IkB.” (DTX 2 at ADL823-33, ADL825.) In response, Ariad sent the PTO a reply on September 12, 2001, canceling all previous claims. It replaced the canceled claims with a new set of claims, 158-87, that did not require the use of agents to practice the claimed methods, along with six new claims, 188-93, that did include a limitation for the “administration of an agent ...” to implement the method of claims 158-75. (Id. at ADL872-88, ADL876-78.) Two days later, in a telephone interview with Examiner David Guzo (“Guzo”), Ariad’s attorney authorized an examiner’s amendment to, inter alia, cancel claims 188-193, the claims requiring the use of an agent. (Id. at ADL923-53, ADL924.) The remaining claims were subsequently allowed as amended by Guzo on October 4, 2001. (Id. at ADL923.) The allowed claims broadly cover a method of inhibiting the expression of a gene whose transcription is regulated by NF-kB in a eukaryotic cell. The only step required to practice the broadest patented method is to “reduc[e] NF-kB activity in the cell such that the expression of said gene is inhibited.” No particular agent or substance need be used, nor any particular step(s) performed, to reduce NF-kB activity in order to practice the invention. C. Lilly’s Drugs Prior to the initial discoveries by the research team at plaintiff institutions, defendant Lilly applied for patents on two compounds, raloxifene hydrochloride and recombinant human activated Protein C (“aPC”). As it happens, these two compounds inhibit NF-kB activity, although Lilly did not know this when it obtained its patents. Lilly began marketing raloxifene hydrochloride under the brand name Evis-ta to treat osteoporosis and has been selling aPC under the name Xigris to treat severe sepsis. At the molecular level, these drugs treat osteoporosis and severe sepsis, respectively, by inhibiting NF-kB activity. D. Commencement of Litigation On the same day that the '516 patent was granted, Ariad filed the instant suit against defendant Lilly, alleging that Lilly’s sales and marketing of Evista and Xigris constituted indirect infringement of twenty claims of the '516 patent. Lilly filed a Combined Motion to Dismiss and Motion for Summary Judgment of Invalidity, contending that the earlier patents on its compounds anticipated the '516 patent and that the methods necessary to practice the '516 patent were not enabled by the written description. I denied the motion but noted that the problem of enablement was troubling, given the broad claim language and the question whether the patent described actual methods for inhibiting NF-kB activity. Ariad Pharmaceuticals, Inc. v. Eli Lilly & Co., Civ. No. 02-11280, 2003 WL 21087115, at *1 (D.Mass. May 12, 2003) (Docket # 33). Late in the discovery process, Lilly petitioned the PTO to reexamine the '516 patent pursuant to 35 U.S.C. § 302, arguing that a large number of the patent’s claims “encompassed numerous prior art methods employing compounds now known to necessarily modulate NF-kB activity.” Lilly Request for Reexamination, Case No. 05-280, April 4, 2005, at 1. Lilly moved to stay the litigation pending the outcome of the PTO’s reexamination, a motion I subsequently denied, as I was not persuaded that reexamination would simplify the issues for trial. Ariad Pharmaceuticals, Inc. v. Eli Lilly and Company, Civ. No. 02-11280, 2005 WL 1342721, at *1 (D.Mass. June 06, 2005) (Docket # 149). Lilly renewed its motion on January 17, 2006, after the PTO granted the reexamination request. I again denied the motion, and the case went to trial in April 2006. E.The Jury Trial After a fourteen-day trial, the jury determined that none of the four claims ultimately asserted were anticipated, either by prior art or public use, and it found all the asserted claims adequately enabled and the written description adequate. The jury further found that a user of Evista directly infringed claims 80 and 95 of the '516 patent and that a user of Xigris directly infringed claims 144 and 145 of the patent. It also found Lilly liable for inducing infringement and contributory infringement by selling the two drugs. The jury determined the effective filing date of the patent to be April 21,1989, and awarded Ariad a royalty of 2.3% on combined sales by Lilly of over $2.83 billion, or over $65 million in damages, as of May 4, 2006. F. Post-Verdict Motions Lilly contends that this award must be set aside because either the '516 patent is invalid, as it claims subject matter not allowed under 35 U.S.C. § 101, or because the patent cannot be enforced as plaintiffs committed a culpable breach of the duty of disclosure and unreasonably delayed prosecution. The parties agree that these issues raise questions of fact and law for the court. See Arrhythmia Research Technology v. Corazonix Corp., 958 F.2d 1053, 1055 (Fed.Cir.1992) (“Whether a claim is directed to statutory subject matter is a question of law.”); Symbol Techs., Inc. v. Lemelson Med., Educ. & Research Found., LP, 422 F.3d 1378, 1385 (Fed.Cir.2005) (“[Prosecution laches] is to be decided as a matter of equity, subject to the discretion of a district court before which the issue is raised.”). G. The Bench Trial A four-day bench trial addressing these issues began on August 7, 2006. Shortly before the commencement of that trial, the PTO, on August 2, 2006, issued a first Office Action in the merged ex parte reexamination proceeding that rejected 160 of the claims in the '516 patent, including the four at issue in this case. (Office Action in Ex Parte Reexamination, Patent 6410516, August 2, 2006 (DTX 973A).) The PTO based its rejections partially on a determination that the claims were inherently anticipated by certain prior art references listed in a review article co-authored by Dr. Albert Baldwin (“Baldwin”), one of the inventors of the '516 patent. In its claim of inequitable conduct, Lilly also charged Baldwin with intentionally withholding this information from the PTO. I examine each of Lilly’s defenses below. III. Discussion A. Validity of the Patent Under 35 U.S.C. § 101 In Lilly’s view, the '516 patent claims subject matter not allowed under 35 U.S.C. § 101 and is therefore invalid. Specifically, it contends that the claims encompass the NF-kB-IkB autoregulatory loop (the “Autoregulatory Loop”), a natural process in cells that operates to reduce the activity of NF-kB. Because natural phenomena are excluded from patentable subject matter, it argues that any '516 claims encompassing the Autoregulatory Loop are invalid and cannot be enforced. Ariad’s response is that the '516 patent does not claim a natural phenomenon because, inter alia, (1) the patent claims a process, subject matter specifically allowed by statute; and (2) the Autoregulatory Loop is only a theory and has not been proven to exist in human cells in vivo. (Docket # 398 ¶ 618.) While not all processes are patentable, I find that Lilly has failed to show that the proposed model of the Autoregulatory Loop actually exists in nature and thus that a natural phenomenon is encompassed by the '516 patent’s claims. 1. Exceptions to Patentable Processes Ariad insists that an analysis of the scope of the patent’s claims is not relevant to a determination of whether the patent claims unpatentable subject matter. It argues that because the '516 patent claims describe the transformation of the activity state in cells, they meet the definition of a process, subject matter specifically allowed under 35 U.S.C. § 101, and the subject matter analysis ends. In its view, any consideration of the scope of the claims only affects whether the claims are anticipated or properly disclosed, issues already decided in its favor by the jury. {See Docket #398 ¶¶ 572-83, 597-602.) This position, however, oversimplifies the law. Congress has broadly defined the subject matter that can be protected by patent. Title 35 U.S.C. § 101 states simply that “[wjhoever invents or discovers any new and useful process, machine, manufacture, or composition of matter ... may obtain a patent therefore.... ” The Committee Reports accompanying the Patent Act of 1952 emphasized the breadth of this statutory subject matter as “including] anything under the sun that is made by man.” Diamond v. Diehr, 450 U.S. 175, 182, 101 S.Ct. 1048, 67 L.Ed.2d 155 (1981) (quoting S.Rep. No.1979, 82d Cong., 2d Sess., 5 (1952); H.R.Rep. No.1923, 82d Cong., 2d Sess., 6 (1952)). “Process,” as used in the statute, is synonymous with “method” and means “a mode of treatment of certain materials to produce a given result.” Id. at 182, 101 S.Ct. 1048. Three exceptions exist, however, to the general principle that any process is eligible for patent protection: “laws of nature, natural phenomena, and abstract ideas.” Id. “The rule that the discovery of a law of nature cannot be patented rests, not on the notion that natural phenomena are not processes, but rather on the more fundamental understanding that they are not the kind of ‘discoveries’ that the statute was enacted to protect.” Parker v. Flook, 437 U.S. 584, 593, 98 S.Ct. 2522, 57 L.Ed.2d 451 (1978). A process, however, is not unpatentable merely because it contains a law of nature; a process employing a law of nature or natural phenomena in a useful way may be protected by patent. Id. at 592, 98 S.Ct. 2522 (distinguishing Morse’s invalid claim, broadly covering the use of electromagnetism to print at a distance, from Neilson’s allowed claim for a machine applying the principle that heated air increases the intensity of the heat in a blast furnace). The court must examine what is sought to be patented in order to determine whether it falls within one of the statutory exceptions. This determination occurs before any consideration whether that discovery meets the requirements for patentability under 35 U.S.C. §§ 102, 103 and 112. Id. at 593, 98 S.Ct. 2522 (“The obligation to determine what type of discovery is sought to be patented must precede the determination of whether that discovery is, in fact, new or obvious.”). Therefore, the asserted claims must be examined to see if they encompass any of these exceptions. If Ariad’s claims are drafted so broadly that they encompass a natural process, they are invalid for claiming unpatentable subject matter. 2. The Autoregulatory Loop Theorizes a Reduction in NF-kB Activity As noted above, Lilly argues that Ariad’s asserted claims encompass a natural phenomenon, the Autoregulatory Loop. Lilly’s scientific expert, Dr. David Latch-man (“Latchman”) described the Aut-oregulatory Loop as a natural process by which the activity of NF-kB in a cell is controlled by IicB-a via negative feedback. (Trial Tr. Day 1, 48:23-52:1.) This process is triggered when an external stimulus causes NF-kB to disassociate from IkB in the cytoplasm of the cell. Free NF-kB then moves into the nucleus and binds to the cell’s DNA. The bound NF-kB stimulates the production of various proteins in the cytoplasm, including certain cyto-kines, but it also causes the production of new IkB. This newly produced IkB reenters the nucleus of the cell and removes the bound NF-kB from the DNA, deactivating it and terminating production of the gene for the induced proteins. The deactivated NF-kB/IkB complex then moves out into the cytoplasm completing the regulatory loop. The NF-kB that was activated by the external stimulus has been deactivated by the IkB that it caused to be generated, naturally terminating the externally induced response. (Id.; see also DTX 3037 (demonstrative video).) a. Support for the Existence of the Autoregulatory Loop The possibility of an NF-kB-IkB regulatory loop was unknown in 1991 when the '516 specification was initially submitted to the PTO and thus is not described in the issued patent. (See DTX 33, ADL14830-ADL15018 (specification filed Nov. 13, 1991 with application 07/791,898).) Latch-man testified that reports on the existence of the Autoregulatory Loop first appeared in three papers published in 1993. (Trial Tr. Day 1, 99:17-100:9.) He cited a number of more recent articles as also supporting his description of the Autoregulatory Loop, including a 1996 review paper by co-inventor Baldwin. (Id. at 54:22-589:19; DTX 24-S.) Latchman also discussed at length an article by Ting & Endy describing the operation of the Autoregulatory Loop. (Trial Tr. Day 1, 60:5-75:10; DTX 469A.) This paper was published as a “Perspective” article to comment on a longer article, published in the same issue of Science, authored by Dr. Alexander Hoffman (“Hoffman”) and, inter alia, co-inventor Dr. David Baltimore (“Baltimore”). (DTX 469.) As explained by Latchman, Ting & Endy described the operation of the Aut-oregulatory Loop based on Hoffman’s experiments comparing cells from natural mice (“wild type”) with cells from genetically engineered “knockout” mice. These so-called “knockout cells” have copies of the gene for IkB inactivated, so that there is no functional IkB-k in the cells. (Trial Tr. Day 1, 58:2-10, 64:13-17.) In wild type cells, a temporary external stimulus of TFN results in only a short period in which NF-kB is present in the nucleus of the cell and in no production of RANTES, a gene activated only after prolonged exposure to NF-kB. The induced active NF-RB is quickly deactivated by new IkB-o¿ produced by the binding of the NF-kB to the DNA before the RANTES gene is expressed. In knockout cells without the ability to produce IkB-cí, a temporary external stimulus of TFN results in a prolonged period in which NF-kB is present in the nucleus of the cell and in the eventual production of the RANTES gene. (Id. at 64:11-69:24.) Unlike the wild type, the level of NF-kB bound in the nucleus of the knockout cell is not reduced by the production of IkB-cí, allowing time for the RANTES gene to be induced. In Latch-man’s opinion, this demonstrates the ability of the Autoregulatory Loop to inhibit induced gene expression. (Id. at 69:25-70:3.) Latchman described the results of additional experiments in which the external stimulus was sustained over a period of time. Even with a continuous stimulus, he asserted that the Autoregulatory Loop operates to reduce the level of NF-kB mediated gene expression in the wild cells, albeit in an oscillatory fashion. (Id. at 66:10-23, 73:15-74:10.) b. Testimony of Ariad’s Expert, Dr. Ravetch Ariad’s expert, Dr. Jeffrey Ravetch (“Ravetch”), objected to Latchman’s conclusion that the Autoregulatory Loop has been proven to exist in living cells. (Trial Tr. Day 3, 10:17-21.) He described the Autoregulatory Loop as a simplified model that poorly explains the experimental data. (Id. at 17:13-18:7.) In his opinion, there are multiple positive and negative regulatory loops operating in cells which, in the aggregate, create the results seen in experimental assays such as those conducted by Hoffman et al. Ravetch rejected the view that just one loop explains the activity of NF-kB in the cell. (Id. at 9:2-12.) The patent claims a reduction of NF-kB in cells, which Ravetch sees as encompassing the net effect of all events, both positive and negative, which occur when a stimulus influences the cell. (Trial Tr. Day 3, 16:2-21.) In addition, Ravetch testified that experiments using cells from knockout mice are conceptually flawed because they assume all other processes in the cell operate the same in the absence of the missing feature, an assumption he believes to be untrue. (Id. at 13:4-14.) Therefore, conclusions from these simplified models cannot be extrapolated back to normal cells because they do not take into consideration effects of the other components operating out of their normal context. (Id. at 13:21 — 14:4; see also id. at 30:19-32.) His opinion was that the scientific community has “established a model for the Autoregulatory Loop” to account for certain observations, but “there is considerable dispute and ongoing study to define its role in the NF-kB signaling pathway.” (Id. at 42:9-21.) Ra-vetch also disputed that numerous scientific articles showed an acceptance by the scientific community of the existence and operation of the Autoregulatory Loop. (See Trial Tr. Day 4, 55:7-70:3.) The articles, in his view, attempt to explain observations of experiments conducted with knockout mice, but the results are inconclusive because of the difficulties in interpreting signal transduction systems where the system has multiple interacting components. (Id. at 73:9-12; see also Trial Tr. Day 3, 32:11-21 (describing a paper in which the authors note their experimental observations are not consistent with the model proposed for the Autoregulatory Loop); id. at 34:2-36:15 (discussing a paper suggesting that a more complex model is necessary to explain the processes occurring in living cells).) Ravetch noted that, far from there being a settled theory congruent with the experimental data, there is still significant ongoing research attempting to explain the complex phenomena taking place within the cell. (Trial Tr. Day 3, 23:4-7.) Finally, Ravetch pointed out that the patent claims processes in living cells, while Latchman’s opinion relied on in vitro research, such as the Hoffman paper (as described by Ting & Endy) to reach his conclusions concerning the Autoregulatory Loop. {See id. at 36:21-37:3.) c. Cross-Examination of Dr. Latch-man On cross-examination, Latchman agreed that the experiments summarized by Ting & Endy were conducted in vitro on cell extractions, not in vivo. (Trial Tr. Day 1, 134:11-18, 140:2-7). He also acknowledged that at his deposition he described the results of their research as “a step along the road,” but not determinative of how IkB-g: works in the human body. (Id. at 148:8-23.) In addition, he admitted that there were discrepancies between the computer model of the Autoregulatory Loop proposed by Ting & Endy and the Hoffman empirical data. (Id. at 155:11-156:6.) Latchman also noted that the computer models of the Autoregulatory Loop are “continually being refined and [that] Hoffman [ ] published a paper as recently as two or three months ago in which he’s changed the model again.” (Id. at 156:6-10.) d. There Is Insufficient Evidence to Invalidate the Patent The '516 patent is “presumed valid.” 35 U.S.C. § 282. In the instant case, Lilly has the burden of proving facts by clear and convincing evidence showing that the patent is invalid. North Am. Vaccine v. American Cyanamid Co., 7 F.3d 1571, 1579 (Fed.Cir.1993). Lilly has not met this burden. While the evidence shows that there has been significant scientific research over more than a decade into the operation of the NF-kB signaling pathway, it has not established that the simplified model of the Autoregulatory Loop proffered by Latch-man operates in vivo in normal cells. Latchman admits that, not only does the current model not fully explain the experimental data, but that the model is continually being refined, even to the present day. Scientists are conducting ongoing research to attempt to more fully explain what happens in cells when subjected to various external stimuli. Ravetch described a complex system of multiple feedback loops, all interacting, to effect the changes in gene expression claimed by the patent. In addition, the experimental data described in the literature has been collected using knockout cells in vitro that have not been shown to operate in all other respects as normal cells. The experimental data cannot be fully explained by the current model. Therefore, I credit Dr. Ravetch’s testimony that the Autoregulatory Loop is “an incomplete model ... subject to a significant amount of ambiguity and inconsistency” (Trial Tr. Day 4, 50:2-6) and find that Lilly has failed to prove by clear and convincing evidence that the Autoregulatory Loop exists in living cells in a way that is encompassed by Ariad’s claims. B. Inequitable Conduct During Prosecution of the '516 Patent Lilly asserts that Ariad, the inventors, and/or their attorneys failed to disclose to the PTO material prior art that demonstrates inherent anticipation of the '516 patent and also failed to disclose material errors in a figure contained in the patent. Although I agree with Lilly that the information that was not disclosed is material, Lilly has failed to prove by clear and convincing evidence the requisite intent necessary to find inequitable conduct and render the patent unenforceable. 1. The Legal Standard for Inequitable Conduct The patent application process is conducted ex parte by inventors and their representatives. Applicants have a duty to prosecute applications with candor, good faith, and honesty. Duro-Last, Inc. v. Custom Seal, Inc., 321 F.3d 1098, 1099 (Fed.Cir.2003); see also 37 C.F.R. § 1.56 (“Each individual associated with the filing and prosecution of a patent application has a duty of candor and good faith in dealing with the [Patent] Office.”). When coupled with an intent to deceive or mislead the PTO, a breach of this duty constitutes inequitable conduct, which renders the patent unenforceable. Bristol-Myers Squibb Co. v. Rhone-Poulenc Rorer, Inc., 326 F.3d 1226, 1233 (Fed.Cir.2003). An applicant breaches this duty by making affirmative misrepresentations of material facts, failing to disclose material information, or submitting false material information. Duro-Last, 321 F.3d at 1099. The Federal Circuit requires that a party asserting inequitable conduct show by “clear and convincing evidence” the elements of materiality and intent to deceive. Burlington Industries, Inc. v. Dayco Corp., 849 F.2d 1418, 1422 (Fed.Cir.1988) (expressing concern about “the habit of charging inequitable conduct in almost every major patent case”). The analysis of inequitable conduct is a two-step process. First the court must determine, as a threshold matter, if both the materiality of the information and the intent to deceive have been established. Bristol-Myers, 326 F.3d at 1234. Once the court has determined that the factual basis for materiality and intent exist, it must “weigh them to determine whether the equities warrant a conclusion that inequitable conduct occurred.” Id. (quoting Molins PLC v. Textron, Inc., 48 F.3d 1172, 1178 (Fed.Cir.1995)). This balancing means that a greater showing of one factor can compensate for a lesser showing of the other. Id. a. Materiality Information is material “where there is a substantial likelihood that a reasonable examiner would consider it important in deciding whether to allow an application to issue as a patent.” Digital Control, Inc. v. Charles Mach. Works, 437 F.3d 1309, 1315 (Fed.Cir.2006) (citing 37 C.F.R. § 1.56 (1977)); accord Bristol-Myers, 326 F.3d at 1234; Molins, 48 F.3d at 1179 n. 8. Under this standard, information can be material even though disclosure of it would not render the invention unpatentable. Digital Control, 437 F.3d at 1318. However, information that is merely cumulative or less pertinent than material considered by the examiner is not material in an inequitable conduct analysis. Molins, 48 F.3d at 1179. b. Intent That the withheld information is material, by itself, is inadequate to prove inequitable conduct. There must also be a showing that the information was withheld with an intent to deceive or mislead the PTO. Allen Organ Co. v. Kimball Int'l., Inc., 839 F.2d 1556 (Fed.Cir.1988) (“Materiality does not presume intent, which is a separate and essential component of inequitable conduct.”). “Intent to deceive can not be inferred solely from the fact that information was not disclosed; there must be a factual basis for a finding of deceptive intent.” Hebert v. Lisle Corp., 99 F.3d 1109, 1116 (Fed.Cir.1996). However, intent to deceive or mislead the PTO can rarely be shown by direct evidence, it is usually inferred from the facts. Bristol-Myers, 326 F.3d at 1239. “[T]he involved conduct, viewed in light of all the evidence, including evidence of good faith, must indicate sufficient culpability to require a finding of intent to deceive.” Digital Control, 437 F.3d at 1319 (internal quotations and citations deleted). Mere error, even conduct that amounts to gross negligence, is not adequate to establish an intent to deceive. Molins, 48 F.3d at 1181. Where the alleged conduct is the nondisclosure of information, there must be clear and convincing evidence that the applicant made a deliberate decision to withhold the information from the PTO. Id. 2. The Allegedly Withheld Information According to Lilly, two errors made during prosecution of the '516 patent meet the threshold standard for materiality: (1) information that was incorrect was not provided to the PTO; and (2) references relevant to inherent anticipation of the claims were not disclosed. a. Errors in Figure 43 First, Lilly points to figure 43, three pages depicting a lengthy nucleotide sequence consisting of the letters A, C, G and T. The central portion of the sequence has sequential groups of these letters identified by an additional single letter below each group of three representing the amino acid sequence. (’516 Patent fig.43.) The Brief Description of the Drawings describes this figure as “the nucleotide sequence and the amino acid sequence of IkB-cí.” (Id. col.10 11.16-17.) The only reference in the specification to figure 43 states: “The nucleotide sequence of the IkB-g: gene and the amino acid sequence of IkB-o: are shown in FIG. 43.” (Id. col.28 11.16-17.) Lilly argues that one skilled in the art reading the patent would expect figure 43 to describe the DNA and amino acid sequence for mammalian, specifically murine (mouse), IkB-ck. However, figure 43 actually shows the sequence of an avian (chicken) protein called pp40. In addition, Lilly claims that the figure is incomplete and only shows portions of the amino acid sequence of pp40. Ariad counters that pp40 is an IkB-c¿ protein, therefore there is no error in the identification of the figure, much less a material misrepresentation. As discussed below, I agree with Lilly that the fact that figure 43 does not represent mammalian DNA meets the threshold standard of materiality necessary to proceed with an evaluation of inequitable conduct. In addition, I find that the sequence in the figure is indeed incomplete as alleged by Lilly. b. References Showing Inherent Anticipation Second, Lilly avers that Ariad failed to disclose references relevant to inherent anticipation of the claims in the '516 patent. Specifically, Lilly argues that after the patent application was filed, at least one of the inventors published both a review article and a paper describing a number of prior art compounds as inhibitors of NF-RB activity. Lilly claims that Ariad had a duty to disclose this information to the PTO. It points to the results of the recent reexamination of the '516 patent, in which the PTO invalidated the claims at least partially on a determination that the claims were inherently anticipated by these references, as showing the materiality of the information withheld. Because I do not find the information withheld was merely cumulative, as Ariad suggests, I conclude it is material. 3. The Materiality of the Errors and Omissions in Figure 43 a. The Description of Figure 43 Is Incorrect Ariad does not dispute that figure 43 represents the nucleotide sequence of avian pp40, not mammalian IkB-cc (See Docket # 398 ¶ 275.) However, it insists that describing pp40 in figure 43 as “the IidB-a gene” is neither incorrect nor misleading and therefore cannot support a claim of inequitable conduct. This conclusion is based on Ariad’s assertion that “the term IkB-ol refers to a family of proteins” capable of inhibiting NF-kB and that “the scientific community has reached a consensus that pp40 is an L<B-a protein.” (Id. ¶¶262, 256.) Ariad further argues that the depiction of avian pp40 in figure 43 is not misleading because the methods claimed in the '516 patent are not limited to mammalian cells. It points to text in the '516 specification explicitly describing the use of pp40, along with mammalian MAD-3, as potential sources for DNA used to negatively regulate NF-kB activity in cells (and thus practice the patented method) in support of this argument. ('516 Patent col.3211.11-40.) Ariad’s argument is disingenuous. While the '516 claims do broadly cover both mammalian and non-mammalian cells, the specification describes the inventors’ work using a mammalian cell line. (’516 Patent col.22 1.23-col.28 1.18.) The Detailed Description of the Invention leading up to the only paragraph referencing figure 43 begins, “[t]he following is a description of the ... discovery of the NF-kB inhibitor IkB ...” (Id. col.10 11.46-52). What then follows is a lengthy discussion of the discovery and isolation of IkB-a from a mu-rine cell line called 70Z/3. {Id. col.22 1.23-col.28 1.18.) The sole mention of figure 43 (describing it as “IkB-gl”) occurs in the text directly following a sentence describing how the inventors determined the characteristics of the IkB they isolated from this murine cell line. {Id. col.28 11.14-18.) The obvious conclusion is that both sentences refer to the same protein. One column later, the patent explicitly refers to “IkB prepared from the mouse [ ] cell line....” {Id. col.29 11.33-34.) A page later, the specification states: “[as] a result of the work described herein, the IkB gene is now available.... ” {Id. col.3111.57-58 (emphasis added).) Latchman testified that in November 1991 when the application containing figure 43 was filed, pp40 was characterized as “an IkB-o: like molecule.” It was not until several years later that pp40 was referred to simply as IkB-oi. (Trial Tr. Day 1, 98:7-99:16.) Furthermore, while the terms “human,” “mammalian,” “murine,” “mouse,” and “70Z/3” occur throughout the specification, “avian” and “chicken” do not appear at all, and “pp40” appears only once. Based on these facts, I find that a reasonable examiner would believe the sequence depicted in figure 43 to represent the nucleotide sequence and the amino acid sequence of murine IkB-oí, not avian pp40. b. Figure 43 Is Incomplete Latchman also testified that figure 43 is incomplete and does not show the correct full amino acid sequence even of pp40. In particular, he stated that figure 43 shows an amino acid sequence that has 82 amino acids at the beginning of the figure that are not present in pp40, but it is missing 56 amino acids at the end, for which are substituted 10 amino acids that are not present in pp40. {Id. at 106:4-20.) The missing region corresponds to a portion of IkB-o: necessary to inhibit DNA binding of NF-kB. (Id.) Based on a comparison of figure 43 with the published sequence of pp40, I credit Latchman’s testimony. Because there is no evidence that Ariad was aware of this error while prosecuting the '516 patent, the error does not affect the issue of intent in evaluating inequitable conduct. See M. Eagles Tool Warehouse, Inc. v. Fisher Tooling Co., 439 F.3d 1335, 1341 (Fed.Cir.2006) (“In an inequitable conduct determination based upon a nondisclosure, the applicant must know, or should have known, of the materiality of the reference for an inference of intent.”). However, it does increase the materiality of the error, because it means that the amino acid sequence shown cannot be used as described in the '516 patent to reduce the activity of NF-kB. c. Figure 43 Is Material Despite Its Late Addition to the Application Ariad suggests that since figure 43 was added to the application in 1991, after the 1989 filing date established by the jury, it is not necessary to the invention and therefore cannot be material, even if wrong. This argument fails under either standard for materiality. Under the “reasonable examiner” standard, the information does not have to preclude patenta-bility to be material. E.g., Digital Control, 437 F.3d at 1318; Bristol-Myers, 326 F.3d at 1237. Even under the stricter standard promulgated by the PTO in 1992, information that “is inconsistent with, a position the applicant takes in: ... (ii) Asserting an argument of patentability” is material. 37 C.F.R. § 1.56(b) (1992). As discussed infra, p. 30, Ariad responded to a PTO section 112 rejection by pointing to the disclosure of Ii<B-a as enabling of its claims, thus “asserting an argument of pat-entability.” Therefore, the error is material regardless of the patent filing date. d. Figure 43 Is Not Cumulative Finally, Ariad’s argument that any disclosure of the error in figure 43 was merely cumulative, because the examiner could have compared the sequence in the patent application with Davis (1991), Fig. 3, is unpersuasive. (Plaintiffs’ Trial Exhibit (“PTX”) 143.) Indeed, as discussed supra, note 29, I find it unreasonable to expect the examiner to compare the sequences. In any case, since figure 43 is not identical to the figure showing pp40 in Davis, even if the examiner had compared the sequences he would not necessarily have realized that figure 43 was an incorrect sequence of pp40 and not the sequence of murine IkB. Id. Ariad also suggests the information is cumulative because one of the examiners of the '516 patent, Dr. Sehwartz-man, was also the primary examiner of the application that issued as the '090 patent. (Docket # 398 ¶ 239-40.) It notified Dr. Schwartzman during the prosecution of the '090 patent that an identical figure in the '090 application was “not the nucleotide sequence of IkB-a but the nucleotide sequence of pp40 relassociated protein.” (Id.) Presumably, Ariad believes that the examiner should sua sponte have applied this information to the examination of the '516 patent as well. The duty of candor and good faith exists to ensure that patent applicants provide accurate material information to the PTO so that the examiner can efficiently and effectively assess their claims. The duty of candor is not so lax that it requires an examiner to compare nucleotide sequences or to track what figures are shared between divisional applications. See also Armour & Co. v. Swift & Co., 466 F.2d 767, 779 (7th Cir.1972) (“[W]e think that it is unfair to a busy Examiner ... to assume that he retains details of every pending file in his mind when he is reviewing a particular application.”). Therefore, I decline to find that information concerning the errors in figure 43 is merely cumulative on that basis. e. The Errors in Figure 43 Are Material Under Both Standards To determine the materiality of the error in figure 43, it is necessary to consider what information the examiner relied on in examining the '516 application during its prosecution. The prosecution history shows that the examiner expressed concern on multiple occasions that the '516 application either did not satisfy the written description requirement or was not enabled. (See, e.g., DTX 2 at ADL611-21, ADL613 (March 11, 1999 PTO Office Action rejecting twenty claims as “containing subject matter which was not described in the specification in such a way as to enable one skilled in the art ... to make and/or use the invention.”); id. at ADL478-88, ADL480 (October 1997 Office Action rejecting claims for lack of enablement and written description); id. at ADL447-55, ADL450-35 (January 1997 Office Action rejecting claims for lack of enablement); id. at ADL822-33, ADL824-25.) In a July 1998 Office Action, the examiner rejected several claims because the specification failed to teach how to purify either the NF-kB or IkB protein. Ariad responded that “the present application teaches how to make recombinant forms of the proteins.” (Id. at ADL570-88, ADL585.) In response to the October 1997 Office Action, the applicants argued that there was adequate disclosure to support, inter alia, that the “artificial induction of IkB could be used as a means of inhibiting NF-kB activities as its regulation of gene transcription.” (Id. at ADL517-40, ADL529.) These rejections and Ariad’s responses show that the DNA sequence of IkB-g: was material because Ariad asserted in an argument for patentability that it taught how to make the protein and thus enabled their claims. The correct sequence information was also necessary in order to incorporate iKB-encoding DNA into the appropriate vector for gene therapy as described by the '516 patent. (’516 Patent eol.32 11.12— 63.) While pp40 is an inhibitor of NF-kB in chickens, it is not clear that it operates similarly in mammals. (Trial Tr. Day 1, 123:2-5.) Latchman testified that in order to have the greatest chance for success in human gene therapy, it is important “to have as much going for you as possible.” (Id. at 101:14-23.) In particular, he warned that using a gene from a non-mammalian species is “more likely to raise an immune reaction and the protein is likely to have functional differences.” (Id.) Thus, the information that the sequence showed avian pp40 and therefore was less likely to enable the claimed method without undue experimentation, would have been of interest to a reasonable examiner, particularly here where enablement was an issue. Cf. Regents of Univ. of Cal. v. Eli Lilly & Co., 119 F.3d 1559, 1567 (Fed.Cir.1997) (finding the disclosure of rat cDNA inadequate to fulfill the written disclosure requirement of a patent claiming human insulin-encoding cDNA). Finally, even if I accept Ariad’s claim that pp40 is an IkB and thus could be used to make or use the invention, the sequence in figure 43 is not the correct sequence of pp40 as shown in Davis (1991). (PTX 143.) For these reasons, I find that the error in figure 43 is material. 4. The Materiality of the Prior Art References Lilly also alleges that Ariad intentionally withheld certain references from the PTO during prosecution of the '516 patent that were material to the question of inherent anticipation. “A patent is invalid for anticipation if a single prior art reference discloses each and every limitation of the claimed invention.” Sobering Corp. v. Geneva Pharms., Inc., 339 F.3d 1373, 1377 (Fed.Cir.2003). Even if a limitation of the claimed invention is missing in the prior art reference, the patent may still be anticipated if “the missing characteristic is necessarily present, or inherent, in the single anticipating reference.” Id. Lilly points to several post-filing references related to the effects on NF-kB activity of various compounds known before the filing date of the patent that it believes should have been provided to the PTO. Specifically, it cites several articles by co-inventor Baldwin, including: Baldwin, A.S., The NF-kB and I kB Proteins: Neio Discoveries and Insights, Annu. Rev. Immunol. 14:649-81 (1996) (DTX 24 — S); Baldwin, A.S., The Transcription Factor NF-kB and Human Disease, J. Clinical Investigation 107(1):3 — 6 (2001) (DTX 25); Scheinman et al., Role of Transcriptional Activation of I kB-ci in Mediation of Immunosuppression by Glucocomcoids, Science 270:283-286 (1995) (DTX 28); and Holmes-McNary, M. and Baldwin, A.S., Chemoprotective Properties of trans-Resveratrol Are Associated with Inhibition of Activation of the IkB Kinase, J. Cancer Research 60:3477-3483 (2000) (DTX 473), (“the Baldwin references”) as well as the relevant references cited in them as disclosing that glucocorticoids, salicylates, cyclosporin A, and resveratrol (Res) — an active ingredient in red wine — all inhibit NF-kB activity. (DTX 24-S at 671; DTX 25 at 4; DTX 28 at 283; DTX 473 at 3481-82.) When these references were brought to the PTO’s attention in the reexamination proceedings, the PTO invalidated the claims at issue in this case as being inherently anticipated. (Office Action in Ex Parte Reexamination, Patent 6410516, August 2, 2006 (DTX 973A).) Lilly argues this demonstrates under both the “reasonable examiner” and stricter “prima facie case of unpatentability” standards that the references were material. See Molins, 48 F.3d at 1179 (noting that “the result of a PTO proceeding that assesses patentability in light of information not originally disclosed can be of strong probative value in determining whether the undisclosed information was material”). Ariad’s counters that these references: (1) were not material because they were cumulative to material already provided to the examiner; and (2) even if they were not cumulative, they were not material because the law at the time included a contemporaneous recognition requirement that one of ordinary skill would have had to recognize the missing information inherently disclosed. a. The Cited References Are Not Cumulative First, Ariad points to a 1994 paper by Ulrich Siebenlist (“Siebenlist 1994”) (DTX 2 at ADL649-73) provided to the PTO as an exhibit to a declaration (id. at ADL625-27) by one of the inventors of the '516 patent, Dr. Baltimore. This first declaration was submitted in support of Ar-iad’s response to a March 17, 1999 PTO Final Office Action rejecting all pending claims for failing to satisfy the enablement requirement of 35 U.S.C. § 112. (See id. at ADL610-21, ADL613; ADL697-704, ADL700.) The copy of the first Baltimore declaration in the PTO prosecution history contains the handwritten notation, “Considered 11/19/99,” followed by Examiner Schwartzman’s initials. Siebenlist 1994 includes brief discussions relevant to inherent anticipation including: (1) that cyclosporin A blocks activation of NF-kB (citing Schmidt et al.1990) (id. at ADL661); and (2) that the actions of steroids, including glucocorticoids, could be explained by their complexing with NF-kB (citing Ray & Perfontaine 1994) (id. at ADL664). While Siebenlist 1994 does not mention resveratrol specifically, it does discuss the inhibition of NF-kB activation by antioxidants. (Id. at ADL659.) Ariad argues this is an adequate disclosure of resveratrol because it is an antioxidant. Next, Ariad points to the response to an August 11, 2000 Office Action that it sent to Examiner Schwartzman on September 12, 2001. (Id. at ADL872-92.) Again, Ariad included a declaration by inventor Baltimore along with 100 pages of attached references. Baltimore described several classes of compounds that “are able to affect NF-kB gene expression” including salicylates (citing, but not providing, a 1999 paper by Yan et al.). (Id. at ADL894-97, ADL895-96.) This response included a copy of a 2000 paper by Fujih-ara (“Fujihara 2000”) citing an number of NF-kB inhibitors previously described including glucocorticoids, aspirin and antioxidants. (Id. at ADL904-12, ADL904.) Less than a month later, on October 4th, Examiner Guzo allowed the amended claims noting that he “ha[d] reviewed the last response and accompanying references which provide substantiating examples of the claimed methods.” (Id. at ADL923-53, ADL952.) Ariad asserts that this language indicates that the examiner considered the post-filing references, including Fujihara 2000, and was aware of the 1999 Yan paper. Because these refer-enees, taken together, disclose use of the same prior art compounds as the references advanced by Lilly, Ariad argues that the withheld references are merely cumulative, and thus cannot be material. Lilly’s response is that the Baltimore declarations and accompanying references were provided only to contest claim rejections based on the written description and enablement requirements. While the PTO did accept the references submitted in support of the applicant’s response to the Office Action without an Information Disclosure Statement (“IDS”), the Manual of Patent Examining Procedure (“MPEP”) at the time implied that the references would only be reviewed for the specific issue being advocated. In addition, Ariad’s response to the Office Action only discussed why the provided references were relevant to the adequacy of the '516 disclosure, not to inherent anticipation. Ariad’s patent attorney for the '516 application, Dr. Matthew Vincent (‘Vincent”), confirmed that Ariad did not read the publications at the time “with any appreciation that someone might argue that they were relevant to inherent anticipation.” (Trial Tr. Day 3, 107:25-108:4.) The PTO Notice of Allowability notes that the examiner amendments to the claims proposed by Ariad were authorized in a telephone interview with Vincent on September 14, 2001, only two days after the examiner received the 100-page document. (DTX 2 at ADL924.) Mr. Lieberstien, Lilly’s patent expert, testified that this kind of examiner’s amendment normally means allowance of the claims. (Trial Tr. Day 2, 105:12-17.) Lilly further notes that the sections of Siebenlist 1994 relevant to inherent anticipation are twenty pages removed from the sections Ariad drew to the attention of the examiner in the first Baltimore declaration. It points out that there is no evidence in the prosecution history that the examiner was aware of the information in Siebenlist 1994 and Fujihara 2000 describing prior art compounds. Finally, none of these references specifically mentions the use of resveratrol or red wine; rather they only discuss the more general use of antioxidants to inhibit NF-RB activity. Given the limited purpose for which the references were proffered, the fact that they were not listed in an IDS, the exceedingly short time between the receipt of the second Baltimore declaration and the examiner’s amendments suggesting allowance, and the lack of specific reference to resveratrol or red wine, I do not find that the Baltimore declarations and attachments adequately disclosed the prior art compounds described in the Baldwin references. Therefore, the Baldwin references are not merely cumulative and thus may be material in an analysis of inequitable conduct. b. Recognition Requirement for Inherent Anticipation Even if the Baldwin references are not merely cumulative, Ariad insists that a reasonable examiner would not have considered them material because at the time the PTO had a recognition requirement for inherent anticipation. Under this doctrine, a reference does not inherently anticipate an invention unless it both necessarily includes the missing element and that missing element would be recognized as necessarily included by a person of ordinary skill at the time. In support of its position, Ariad points to instructions to the examiner on inherent anticipation in the edition of the MPEP in effect at the time of the '516 prosecution: To establish inherency, the extrinsic evidence must make clear that the missing descriptive matter is necessarily present in the thing described in the reference, and that it would be so recognized by persons of ordinary skill. MPEP § 2112 (7th ed. July 1998) (citing In re Robertson, 169 F.3d 743, 745 (Fed.Cir.1999)) (internal quotations omitted). Ariad contrasts this language with the subsequent edition of the MPEP, which explicitly states that contemporaneous recognition is not a requirement for inherent anticipation. It argues that this shows that a change in the PTO’s position on inherent anticipation occurred after the prosecution of the '516 patent which eliminated the recognition requirement. (See Docket # 398 ¶¶ 121-124.) The difficulty with this argument is that the 7th edition of the MPEP did not require contemporaneous recognition, only an ultimate recognition of the inherency, and it is not in conflict with the additional guidance provided in the later edition. Moreover, with one exception, the cases relied upon by Ariad, while requiring recognition by persons of ordinary skill, are silent as to whether that recognition must be contemporaneous with the date of the reference. See Robertson, 169 F.3d at 745. (“the extrinsic evidence must make clear that the missing descriptive matter ... would be so recognized by persons of ordinary skill”) (internal quotations removed); Continental Can Co. v. Monsanto Co., 948 F.2d 1264, 1268, (Fed.Cir.1991) (same); Electro Med. Sys., S.A. v. Cooper Life Sciences, Inc., 34 F.3d 1048, 1052 (Fed.Cir.1994) (“EMS was required to prove ... and that it would be so recognized by persons of ordinary skill.”). The sole exception that explicitly required contemporaneous recognition is Elan Pharms., Inc. v. Mayo Found. For Med. Educ. & Research, 304 F.3d 1221 (Fed.Cir.2002) (“[I]t must be shown that the undisclosed information was known to be present in the subject matter of the reference.”), vacated 314 F.3d 1299 (Fed.Cir.2002), and superceded 346 F.3d 1051 (Fed.Cir.2003). However, that decision was vacated and the new decision does not contain a similar requirement. (Id.) Also, as Lilly points out, Elan was decided after the '516 patent issued, so it could not have been considered by the examiner as a statement of the law at the time of the '516 prosecution. I note that Schering, the case cited in the 8th edition of the MPEP, explicitly rejected both the holding in Elan and Ariad’s reading of Continental Can as requiring contemporaneous recognition. Schering, 339 F.3d at 1377. In addition, the examiner of the '516 patent continued to reject a claim even after Ariad argued that there was no contemporaneous recognition in the reference to support the examiners inherent anticipation rejection. In that instance, Ariad asserted that the reference Wall et al. could not be prior art because it did not “teach or suggest that NF-kB is a transacting nuclear factor, nor do they teach or suggest that NF-kB binds to the enhancer of the g gene.” (DTX 2 at ADL470-71.) The examiner, in maintaining the rejection, stated that “[although these references do not teach the NF-kB — IkB-<x complex, the role of NF-kB as a transcription factor or the presence of NF-kB binding sites in the expressed genes, these are inherent properties of the cells and the genes.” (DTX 2 at ADL486.) This indicates that the examiner of the '516 patent did not accept Ariad’s argument that there was a contemporaneous recognition requirement for inherent anticipation. Thus, the case law and the '516 examiner’s actions support Lilly’s position that a reasonable examiner would not reject references describing use of thé prior art compounds because of a lack of contemporaneous recognition of their mode of action. I therefore find that the Baldwin references are material because: (1) they disclose references pertaining to prior art compounds that the examiners, on reexamination, found were material to the issue of patentability; (2) they are not cumulative to references provided during the prosecution of the '516 patent, and; (3) a reasonable examiner, at the time of the prosecution of the '516 patent, would not have believed there was a contemporaneous recognition requirement for inherent anticipation. 5. Evidence of Intent Concerning the Errors in Figure 43 Lilly argues that Ariad’s patent attorneys were not only aware that figure 43 was not the sequence of IkB-cs as described, but also that the information was material to the asserted claims. In addition, Lilly suggests that Ariad had a strong motivation to conceal this information because disclosure might have required Ariad to refile the application and lose the benefit of the transitional rules. Without the benefit of the transitional rules, the patent would have expired on January 9, 2006, twenty years from its original filing date, rather than seventeen years from issuance, in 2019. Lilly asserts that the failure to inform the PTO of the error, coupled with the desire to secure an additional thirteen years of patent monopoly, provides adequate circumstantial evidence of an intent to conceal material information and justify a finding of inequitable conduct. (See Docket # 397 ¶¶ FF110-18.) a. The Prosecuting Firm and Attorney History of the '516 Patent The complexity of the prosecuting attorney history of the '516 patent rivals that of its PTO prosecution history. Figure 43, identified as “the nucleotide sequence and the amino acid sequence of IkB-g:,” was added as new matter in application 07/791,898, a continuation-in-part of several earlier Ariad applications, filed November 13, 1991. (DTX 33 at ADL14822, 14851.) This application was eventually abandoned, but not before a continuation application, 08/418,266 (“the '266 application”), also containing figure 43 was filed on April 6, 1995. The '266 application spawned two divisional applications containing figure 43, 08/463,397 (“the '397 application”) and 08/464,364, which issued as the '516 patent. (See DTX 3300 (demonstrative exhibit showing the '516 patent family lineage).) The '266 application eventually issued as U.S. Patent No. 5,804,374 on September 8, 1998. After the claims were allowed, but before the patent issued, figure 43 was deleted from the '266 application. At that time the applications were being prosecuted by the firm of Hamilton, Brooks, Smith & Reynolds, P.C. Lisa Warren (“Warren”), an attorney associated with that firm, filed an amendment with the PTO on September 15, 1997, to remove figure 43 and more than 30 other figures. (DTX 34 at ADL15351-71.) Warren explained in the amendment that the applicants did not believe the deleted figures were necessary for an understanding of the invention. (Id. at 15370.) However, she also noted that “[i]t has recently come to the Applicants’ Attorneys’ attention that figure 43 is not the nucleotide sequence of IkBck but the nucleotide sequence of pp40 rel-associated protein.” (Id.) This information apparently had been provided by Ariad employee Sharon Hausdorff (“Hausdorff”). (See Clauss Dep. Tr., 44:18-22, 62:2-6.) The PTO subsequently disapproved the request to amend due to confusion over the adequacy of the amendment. (DTX 34 at ADL15341.) In late 1997, after this amendment was filed, but before it had been denied by the PTO, responsibility for prosecution of the outstanding applications was transferred to the firm of Foley, Hoag & Elliot LLP (“Foley Hoag”). (Id. at ADL15373.) Dr. Isabelle Clauss (“Clauss”) was responsible for the day-to-day work on the applications. However, Clauss had only limited recognition to prosecute patents for others before the PTO. She worked with Vincent, who was the attorney at Foley Hoag responsible for the overall strategy for the prosecution of the Ariad applications. (Trial Tr. Day 3, 44:16-25, 89:13-25.) Vincent, an associate only three years her senior, testified