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US Supreme Court Finds that a Review of Factual Findings in the Construction a Patent Claim Will Only be Entertained in Cases of Clear Error

US Supreme Court Finds that a Review of Factual Findings in the Construction a Patent Claim Will Only be Entertained in Cases of Clear Error

Teva Pharmaceuticals USA, Inc., Et Al. V. Sandoz, Inc., Et Al.

Certiorari To The United States Court Of Appeals For The Federal Circuit Supreme Court Of The United States

No. 13–854.

Roberts J. CJ, Scalia A. AJ, Kennedy A. AJ, Thomas C. AJ, Ginsburg R. AJ, Breyer S. AJ, Alito S. AJ, Sotomayor S. AJ, Kagan E. AJ,

January 20, 2015

Reported by Monica Achode

Brief Facts:

The petitioners, Teva Pharmaceuticals (and related firms), owned a patent that covered a manufacturing method for the multiple sclerosis drug Copaxone. When respondents, Sandoz, Inc. (and other firms), tried to market a generic version of the drug, Teva sued them for patent infringement. Sandoz countered that the patent was invalid. Specifically, Sandoz argued that the claim that Copaxone’s active ingredient had a molecular weight of 5 to 9 kilodaltons which was fatally indefinite, because it did not state which of three methods of calculation – i.e., the weight of the most prevalent molecule, the weight as calculated by the average weight of all molecules, or weight as calculated by an average in which heavier molecules counted for more – was used to determine that weight.

After considering conflicting expert evidence, the District Court concluded that the patent claim was sufficiently definite and the patent was thus valid. As relevant there, it found that in context a skilled artisan would understand that the term “molecular weight” referred to molecular weight as calculated by the first method. In finding the molecular weight term indefinite and the patent invalid on appeal, the Federal Circuit reviewed de novo all aspects of the District Court’s claim construction, including the District Court’s determination of subsidiary facts.


Whether a district court’s factual finding in support of its construction of a patent claim term could be reviewed de novo, as the Federal Circuit required or only for clear error, as Rule 52(a) required

Federal Rules of Civil Procedure

Rule 52 Findings and conclusions by the court; judgment on partial findings

(a) Findings And Conclusions.

(1) In General. In an action tried on the facts without a jury or with an advisory jury, the court must find the facts specially and state its conclusions of law separately. The findings and conclusions may be stated on the record after the close of the evidence or may appear in an opinion or a memorandum of decision filed by the court. Judgment must be entered under Rule 58. * *

(b) Setting Aside the Findings.

Findings of fact, whether based on oral or other evidence, must not be set aside unless clearly erroneous, and the reviewing court must give due regard to the trial court’s opportunity to judge the witnesses’ credibility.

Intellectual Law – patent Law – construction of a patent claim – standard of law to be used in the construction of a patent claim – whether the construction of a patent was a matter of fact or of law – circumstances under which a determination of a matter of fact would precede the function of construction – whether the court constructed the patent as per the prescribed standard of law

Civil Practice and Procedure – review – review of a district court’s findings – function of an appeals court reviewing the findings of a district court sitting without a jury – circumstances under which an appeals court could  set aside a district court’s findings of fact – exceptions – clear error rule vis-à-vis the de novo standard of review – importance of the “clear error” rule in patent cases – whether the Federal Circuit court properly applied the necessary standard of review

Words and Phrases – meaning of “clear error” – manner in which the “clear error” standard was to be applied when reviewing subsidiary fact finding in patent claim construction – whether the Federal Circuit court had applied the standard appropriately


  1. When reviewing a district court’s resolution of subsidiary factual matters made in the course of its construction of a patent claim, the Federal Circuit had to apply a “clear error”, not a “de novo”, standard of review. Federal Rule of Civil Procedure 52(a)(6) stated that a court of appeals was not to set aside a district court’s findings of fact unless they were clearly erroneous. It set out a clear command, and did not make exceptions or exclude certain categories of factual findings from the court of appeals’ obligation. The Rule applied to both subsidiary and ultimate facts. Thus the function of an appeals court reviewing the findings of a district court sitting without a jury was not to decide factual issues de novo.
  2. Even if exceptions to the Rule were permissible, there was no convincing ground for creating an exception here. In the case of Markman vs Westview Instruments, Inc., 517 U. S. 370 the Court held that the ultimate question of claim construction was for the judge, not the jury, but it did not thereby create an exception from the ordinary rule governing appellate review of factual matters. Instead, the Court pointed out that a judge, in construing a patent claim, was engaged in much the same task as the judge would be in construing other written instruments, such as deeds, contracts, or tariffs.
  3. Construction of written instruments often presented a question solely of law, at least when the words in those instruments were used in their ordinary meaning. However, if a written instrument used technical words or phrases not commonly understood, those words could give rise to a factual dispute. If so, extrinsic evidence could help to establish a usage of trade or locality. In that circumstance, the determination of the matter of fact would precede the function of construction.
  4. The Markman court also recognized that courts would sometimes had to resolve subsidiary factual disputes in patent construction; Rule 52 required appellate courts to review such disputes under the “clearly erroneous” standard.
  5. “Clear error” review was particularly important in patent cases because a district court judge who had presided over, and listened to, the entire proceeding had a comparatively greater opportunity to gain the necessary familiarity with specific scientific problems and principles, than an appeals court judge who had to read a written transcript or perhaps just those portions referenced by the parties.
  6. Arguments to the contrary were unavailing. Sandoz, the respondent, claimed that separating factual from legal questions would be difficult and, like the Federal Circuit, posited that it was simpler for the appellate court to review the entirety of the district court’s claim construction de novo than to apply two separate standards.  However, courts of appeals had long been able to separate factual from legal matters, and the Federal Circuit’s efforts to treat factual findings and legal conclusions similarly had brought with them their own complexities.
  7. As for the respondent’s argument that “clear error” review would bring about less uniformity, neither the Circuit nor Sandoz had showed that divergent claim construction stemming from divergent findings of fact on subsidiary matters could occur more than occasionally.
  8. When the district court reviewed only evidence intrinsic to the patent, the judge’s determination was solely a determination of law, and the court of appeals would review that construction de novo. However, where the district court needed to consult extrinsic evidence in order to understand, for example, the background science or the meaning of a term in the relevant art during the relevant time period, and where those subsidiary facts were in dispute, courts would need to make subsidiary factual findings about the extrinsic evidence. The district judge, after deciding the factual dispute, would then interpret the patent claim in light of the facts as he had found them.
  9. The ultimate construction of the claim was a legal conclusion that the appellate court could review de novo. But to overturn the judge’s resolution of an underlying factual dispute, the appellate court had to find that the judge, in respect to those factual findings, had made a clear error. The Federal Circuit erred in failing to review the district court’s factual finding only for clear error and therefore improperly applied the de novo standard of review.

Federal Circuit’s opinion vacated and remanded for delivery by Breyer AJ

Dissenting Opinion of Thomas C. AJ, & Alito AJ

  1. There was no special exception to Federal Rule of Civil Procedure 52(a)(6) for claim construction, but that was not the question in the case. The question was whether claim construction involved findings of fact. Because it did not, Rule 52(a)(6) did not apply, and the Court of Appeals properly applied a de novo standard of review. Reaching the contrary conclusion the court failed to engage the vexing distinction between questions of fact and questions of law.
  2. Unfortunately, Rule 52(a) did not furnish particular guidance with respect to distinguishing law from fact, and the court found it difficult to discern any other rule or principle that would unerringly differentiate the two. Instead, it considered how findings of fact and conclusions of law were understood at the time Rule 52 was adopted.
  3.  Patents were written instruments, so other written instruments supplied the logical analogy per the Markman case. As the majority recognized, the construction of written instruments was generally a question of law, but in certain contexts, a court construing a written instrument could make subsidiary determinations that the law be treated as findings of fact.
  4. The ultimate meaning of a patent claim, like the ultimate meaning of a statute, bound the public at large, it could not depend on the specific evidence presented in a particular infringement case. Although the party presentations shaped even statutory construction, de novo review on appeal helped to ensure that the construction was not skewed by the specific evidence presented in a given case.
  5.  The majority made little effort to justify its assertion that the subsidiary determinations a district court made in the course of claim construction were findings of fact. The majority’s unexamined reliance on technical usage could be read to cast doubt on the practice of treating the inquiry into those meanings as involving only conclusions of technical unknown meanings of statutes outside the specialized community.
  6. The need for uniformity in claim construction also weighed heavily in favor of de novo review of subsidiary evidentiary determinations. Uniformity was a critical feature of our patent system because the limits of a patent had to be known for the protection of the patentee, the encouragement of the inventive genius of others and the assurance that the subject of the patent would be dedicated ultimately to the public.

Relevance to the Kenyan Situation

Superior Courts in Kenya exercises general criminal and civil jurisdiction over various Intellectual Property related matters depending on the subject matter of Intellectual Property under review, and the stage of the legal proceedings. In summary, the Courts’ general jurisdiction may arise under various circumstances.

Under the Constitution, property includes any vested or contingent right to, or interest in or arising from inter-alia Intellectual Property and every person has the right, either individually or in association with others, to acquire and own property of any description. To that extent, Intellectual Property rights are deemed to be Constitutionally protected and the state has a duty to support, promote and protect the Intellectual Property rights of the people of Kenya.

The High Court in exercise of its unlimited original jurisdiction on any question touching on a person’s above Constitutional rights to Intellectual Property may entertain a suit arising from the above rights. Anyone can therefore institute proceedings in the High Court for the protection of his Intellectual Property rights by virtue of he High Court’s original and unlimited jurisdiction .

The Kenyan Court of Appeal only hears matters of law on appeal and this was a well established principle. In its appellate jurisdiction, the Court of Appeal has rendered several landmark decisions touching on a number of significant questions on Intellectual Property law, the most significant one being a patent infringement case of Sanitam Containers vs Rentokil (K) Ltd & Anor [eKLR 2006]. The court went on to state that it had to reconsider the evidence, evaluate it itself and draw its own conclusions though it would always bear in mind that it had neither seen nor heard the witnesses and had to make due allowance in that respect.

In particular, it was not bound necessarily to follow the trial judge’s findings of fact if it appeared either that he had clearly failed on some point to take account of particular circumstances or probabilities materially to estimate the evidence, or if the impression based on the demeanor of a witness was inconsistent with the evidence in the case generally. Subject to those principles, appellate court would not lightly differ from the judge at first instance on a finding of fact. It also noted that burden of proof in matters relating to infringement of industrial property rights would lie with those who claimed their rights had been infringed and any proceedings using a reversal of the burden of proof had to be null an

Case Study Of Kenya’s Specialized Intellectual Property Rights Court Regime By Justice N.R. Ombija Nairobi, December 2011. Copyright 2011. International Intellectual Property Institute. All rights Reserved. The Opinions expressed herein are those solely of Justice N.R. Ombija and do not represent the views of the International Intellectual Property Institute (IIPI).–

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