非衡平行為の成立要件は、欺く意図（intent to deceive）および重要性（Materiality）の要件を満たすことであり、これらの要件は、明確かつ確実な証拠により証明されなければならないとされている（Kingsdown Medical Consultants, Ltd. v. Hollister Inc., 863 F. 2d 867, 9 U.S.P.Q. 2d 1384 (Fed. Cir. 1988)）
欺く意図の立証基準に関し、CAFCは、「知り得たであろう（should have known）」という、重大なまたは通常の過失（gross negligence or negligence）に基づく証拠基準を廃止し、被疑侵害者は、特許権者がUSPTOを欺く特定の意図をもって行動したということを立証しなければならないとした。
To prevail on a claim of inequitable conduct, the accused infringer must prove that the patentee acted with the specific intent to deceive the PTO. Star, 537 F.3d at 1366 (citing Kingsdown, 863 F.2d at 876). A finding that the misrepresentation or omission amounts to gross negligence or negligence under a “should have known” standard does not satisfy this intent requirement. Kingsdown, 863 F.2d at 876. “In a case involving nondisclosure of information, clear and convincing evidence must show that the applicant made a deliberate decisionto withhold a known material reference.” Molins, 48 F.3d at 1181 (emphases added). In other words, the accused infringer must prove by clear and convincing evidence that the applicant knew of the reference, knew that it was material, and made a deliberate decision to withhold it.
Because the party alleging inequitable conduct bears the burden of proof, the “patentee need not offer any good faith explanation unless the accused infringer first . . . prove[s] a threshold level of intent to deceive by clear and convincing evidence.” Star, 537 F.3d at 1368. The absence of a good faith explanation for withholding a material reference does not, by itself, prove intent to deceive.
・重要性（Materiality）
CAFCは、”but for”基準を採用した。即ち、もしその先行技術文献が開示されていれば、USPTOはクレームを許可しなかったであろうということを、証拠の優越的基準（a preponderance of evidence）に基づいて立証することが必要とされた。
This court holds that, as a general matter, the materiality required to establish inequitable conduct is but-for materiality. When an applicant fails to disclose prior art to the PTO, that prior art is but-for material if the PTO would not have allowed a claim had it been aware of the undisclosed prior art. Hence, in assessing the materiality of a withheld reference, the court must determine THERASENSE v. BECTON 28whether the PTO would have allowed the claim if it had been aware of the undisclosed reference. In making this patentability determination, the court should apply the preponderance of the evidence standard and give claims their broadest reasonable construction. See Manual of Patent Examining Procedure (“MPEP”) §§ 706, 2111 (8th ed. Rev. 8, July 2010).
一方、CAFCは、従来、用いてきたスライディングスケールは用いるべきでないとも述べている。
Intent and materiality are separate requirements. Hoffmann-La Roche, Inc. v. Promega Corp., 323 F.3d 1354, 1359 (Fed. Cir. 2003). A district court should not use a “sliding scale,” where a weak showing of intent may be found sufficient based on a strong showing of materiality, and vice versa.
また、CAFCは、USPTO規則56(規則1.56)の定義に基づく基準は採用しないとした。
This court does not adopt the definition of materiality in PTO Rule 56. As an initial matter, this court is not bound by the definition of materiality in PTO rules. See Merck & Co., Inc. v. Kessler, 80 F.3d 1543, 1549-50 (Fed. Cir. 1996) (“[T]he broadest of the PTO’s rulemaking powers . . . does NOT grant the Commissioner the authority to issue substantive rules.”); see also 57 Fed. Reg. 2021 (Jan. 17, 1992) (The PTO stated that Rule 56 “do[es] not define fraud or inequitable conduct.”). While this court respects the PTO’s knowledge in its area of expertise, the routine invocation of inequitable conduct in patent litigation has had adverse ramifications beyond its effect on the PTO. As discussed above, patent prosecutors, inventors, courts, and the public at large have an interest in reining in inequitable conduct. Notably, both the American Bar Association and the American Intellectual Property Law Association, which represent a wide spectrum of interests, support requiring but-for materiality (which is absent from Rule 56).
Although but-for materiality generally must be proved to satisfy the materiality prong of inequitable conduct, this court recognizes an exception in cases of affirmative egregious misconduct. This exception to the general rule requiring but-for proof incorporates elements of the early unclean hands cases before the Supreme Court, which dealt with “deliberately planned and carefully executed scheme[s]” to defraud the PTO and the courts. HazelAtlas, 322 U.S. at 245. When the patentee has engaged in affirmative acts of egregious misconduct, such as the filing of an unmistakably false affidavit, the misconduct is material. See Rohm & Haas Co. v. Crystal Chem. Co., 722 F.2d 1556, 1571 (Fed. Cir. 1983) (“there is no room to argue that submission of false affidavits is not material”); see also Refac Int’l, Ltd. v. Lotus Dev. Corp., 81 F.3d 1576, 1583 (Fed. Cir. 1996) (finding the intentional omission of declarant’s employment with inventor’s company rendered the affidavit false and that “[a]ffidavits are inherently material”). After all, a patentee is unlikely to go to great lengths to deceive the PTO with a falsehood unless it believes that the falsehood will affect issuance of the patent. See id. at 247 (pointing out that patentee’s lawyers “went to considerable trouble and expense” to manufacture false evidence because they believed it was needed to obtain issuance of the patent).
〒541－0041
Therasense, Inc. v. Becton, Dickinson and Company (Fed. Cir. 2011) (en banc)
・差し戻し
・非衡平行為、欺く意図、重要性、but for 基準、IDS
（事件の背景）
出願人が意図的に重要な先行技術文献を開示せずに特許付与がされた場合、そのような行為は非衡平行為（Inequitable Conduct）であるとして、当該特許に基づく権利行使が不能とされる。
非衡平行為の成立要件は、欺く意図（intent to deceive）および重要性（Materiality）の要件を満たすことであり、これらの要件は、明確かつ確実な証拠により証明されなければならないとされている（Kingsdown Medical Consultants, Ltd. v. Hollister Inc., 863 F. 2d 867, 9 U.S.P.Q. 2d 1384 (Fed. Cir. 1988)）
そして、裁判所はこれまで、欺く意図または重要性に関する何れかの証拠が強力である場合は、他方の弱い証拠を補完するとする、いわゆるスライディングスケール（sliding scale）アプローチを採用してきた。
（CAFCの判断）
・欺く意図（intent to deceive）
欺く意図の立証基準に関し、CAFCは、「知り得たであろう（should have known）」という、重大なまたは通常の過失（gross negligence or negligence）に基づく証拠基準を廃止し、被疑侵害者は、特許権者がUSPTOを欺く特定の意図をもって行動したということを立証しなければならないとした。
具体的には、出願人がその先行技術文献を知り、それが重要であることも知っており、かつ、それを意図的に開示しないと決定したことを示す明確かつ確実な証拠を立証しなければならないとされた。
To prevail on a claim of inequitable conduct, the accused infringer must prove that the patentee acted with the specific intent to deceive the PTO. Star, 537 F.3d at 1366 (citing Kingsdown, 863 F.2d at 876). A finding that the misrepresentation or omission amounts to gross negligence or negligence under a “should have known” standard does not satisfy this intent requirement. Kingsdown, 863 F.2d at 876. “In a case involving nondisclosure of information, clear and convincing evidence must show that the applicant made a deliberate decisionto withhold a known material reference.” Molins, 48 F.3d at 1181 (emphases added). In other words, the accused infringer must prove by clear and convincing evidence that the applicant knew of the reference, knew that it was material, and made a deliberate decision to withhold it.
また、特許権者に対しては、誠意（good faith）をもって、文献を開示しなかった理由を説明する責任はなく、「誠意のある説明をしなかったこと自体は、欺く意図を示すものではない」とされた。
Because the party alleging inequitable conduct bears the burden of proof, the “patentee need not offer any good faith explanation unless the accused infringer first . . . prove[s] a threshold level of intent to deceive by clear and convincing evidence.” Star, 537 F.3d at 1368. The absence of a good faith explanation for withholding a material reference does not, by itself, prove intent to deceive.
・重要性（Materiality）
CAFCは、”but for”基準を採用した。即ち、もしその先行技術文献が開示されていれば、USPTOはクレームを許可しなかったであろうということを、証拠の優越的基準（a preponderance of evidence）に基づいて立証することが必要とされた。
This court holds that, as a general matter, the materiality required to establish inequitable conduct is but-for materiality. When an applicant fails to disclose prior art to the PTO, that prior art is but-for material if the PTO would not have allowed a claim had it been aware of the undisclosed prior art. Hence, in assessing the materiality of a withheld reference, the court must determine THERASENSE v. BECTON 28whether the PTO would have allowed the claim if it had been aware of the undisclosed reference. In making this patentability determination, the court should apply the preponderance of the evidence standard and give claims their broadest reasonable construction. See Manual of Patent Examining Procedure (“MPEP”) §§ 706, 2111 (8th ed. Rev. 8, July 2010).
一方、CAFCは、従来、用いてきたスライディングスケールは用いるべきでないとも述べている。
Intent and materiality are separate requirements. Hoffmann-La Roche, Inc. v. Promega Corp., 323 F.3d 1354, 1359 (Fed. Cir. 2003). A district court should not use a “sliding scale,” where a weak showing of intent may be found sufficient based on a strong showing of materiality, and vice versa.
また、CAFCは、USPTO規則56(規則1.56)の定義に基づく基準は採用しないとした。
This court does not adopt the definition of materiality in PTO Rule 56. As an initial matter, this court is not bound by the definition of materiality in PTO rules. See Merck & Co., Inc. v. Kessler, 80 F.3d 1543, 1549-50 (Fed. Cir. 1996) (“[T]he broadest of the PTO’s rulemaking powers . . . does NOT grant the Commissioner the authority to issue substantive rules.”); see also 57 Fed. Reg. 2021 (Jan. 17, 1992) (The PTO stated that Rule 56 “do[es] not define fraud or inequitable conduct.”). While this court respects the PTO’s knowledge in its area of expertise, the routine invocation of inequitable conduct in patent litigation has had adverse ramifications beyond its effect on the PTO. As discussed above, patent prosecutors, inventors, courts, and the public at large have an interest in reining in inequitable conduct. Notably, both the American Bar Association and the American Intellectual Property Law Association, which represent a wide spectrum of interests, support requiring but-for materiality (which is absent from Rule 56).
尚、CAFCは、特許権者が「積極的な悪質不正行為（affirmative egregious misconduct）」を行なったとされる場合には、”but for”基準に基づく重要性の立証は不要であるとも述べている。
Although but-for materiality generally must be proved to satisfy the materiality prong of inequitable conduct, this court recognizes an exception in cases of affirmative egregious misconduct. This exception to the general rule requiring but-for proof incorporates elements of the early unclean hands cases before the Supreme Court, which dealt with “deliberately planned and carefully executed scheme[s]” to defraud the PTO and the courts. HazelAtlas, 322 U.S. at 245. When the patentee has engaged in affirmative acts of egregious misconduct, such as the filing of an unmistakably false affidavit, the misconduct is material. See Rohm & Haas Co. v. Crystal Chem. Co., 722 F.2d 1556, 1571 (Fed. Cir. 1983) (“there is no room to argue that submission of false affidavits is not material”); see also Refac Int’l, Ltd. v. Lotus Dev. Corp., 81 F.3d 1576, 1583 (Fed. Cir. 1996) (finding the intentional omission of declarant’s employment with inventor’s company rendered the affidavit false and that “[a]ffidavits are inherently material”). After all, a patentee is unlikely to go to great lengths to deceive the PTO with a falsehood unless it believes that the falsehood will affect issuance of the patent. See id. at 247 (pointing out that patentee’s lawyers “went to considerable trouble and expense” to manufacture false evidence because they believed it was needed to obtain issuance of the patent).
・非衡平行為の適用
CAFCは、基本的な公正さに基づく衡平法の原則として、特許権者の行為が不当なクレーム発行という公正を欠いた利益をもたらした場合にのみ、非衡平行為が適用されるべきと述べている。
以上の様に、CAFCは今回欺く意図および重要性に関する新テストを採用し、地裁の判断については、これらの要件を十分に考慮していないとして、事件を地裁に差し戻した。
本件は、被疑侵害者に対する非衡平行為の立証基準を引き上げるものであり、これまでよりもその立証が難しくなった。現在、USPTOはこの判決を受けて、検討中であるとの発表をしている。今後、米国出願に対するIDS提出などにも影響が出ると思われ、動向が注目される。
（判決文） http://www.patentlyo.com/therasensefrompatentlyo.pdf