United States: En Banc Federal Circuit Confirms De Novo Appellate Review Of Claim Construction

In Lighting Ballast Control LLC v. Philips Electronics North America Corp., No. 12-1014 (Fed. Cir. Feb. 21, 2014) (en banc), the Federal Circuit en banc confirmed Cybor Corp. v. FAS Technologies, Inc., 138 F.3d 1448 (Fed. Cir. 1998) (en banc), that claim construction is purely a matter of law subject to de novo appellate review.

Lighting Ballast Control LLC ("Lighting Ballast") asserted infringement of U.S. Patent No. 5,436,529, which relates to electric circuits used in fluorescent lighting.  The district court construed the claim term "voltage source means" not as a means-plus-function limitation under 35 U.S.C. § 112, ¶ 6, but as corresponding to a class of structures.  The district court then entered judgment for Lighting Ballast following a jury trial.  On appeal, a panel of the Federal Circuit reviewed the district court's claim construction without deference, holding that the term "voltage source means" invoked means-plus-function claiming and was invalid for indefiniteness because the specification disclosed no corresponding structure.  The Court then granted rehearing en banc to reconsider the standard of appellate review of claim construction.

In a split decision, a majority of the en banc Federal Circuit applied the principles of stare decisis and confirmed the Cybor standard of de novo review of claim construction as a matter of law.  The Court first characterized the three general positions expressed by the parties and amici:  (1) abandonment of the Cybor standard for deferential review of claim construction as a question of fact; (2) adoption of a hybrid-review standard with deferential review of the factual aspects of claim construction but with the ultimate construction a legal conclusion subject to de novo review; and (3) affirmance of the Cybor standard of de novo review.  The Court next considered the principles of stare decisis, explaining that overturning Cybor required more than controversy regarding the prior standard.  Rather, according to the Court, a departure from precedent may be appropriate when subsequent cases have undermined its doctrinal underpinnings, when the precedent has proved unworkable, or when a considerable body of new experience requires changing the law. 

Applying these principles, the Federal Circuit held that the proponents of overruling Cybor had not met the demanding standards of the doctrine of stare decisis.  The Court first concluded that no subsequent developments from the Supreme Court, Congress, or the Court had undermined the reasoning of Cybor.  The Court also concluded that fifteen years of experience had demonstrated the ready workability of the Cybor standard.  Reversing or modifying this standard, the Court explained, could decrease workability and increase litigation burdens by adding a new and uncertain inquiry given that no one, including the dissent, had proposed a workable replacement standard.  Moreover, according to the Court, a more deferential review standard would neither be more likely to achieve the correct claim construction nor affect a large number of claim construction disputes, because claim construction is a legal standard of the scope of the patent right, which does not turn on witness credibility and is not transformed into a matter of fact by reliance on extrinsic evidence.  In fact, the Court reasoned, given the increased frequency with which the same patent is asserted in different forums against different defendants, giving deference to a district court's claim construction might prevent the uniform treatment of a given patent and result in the forum shopping the Federal Circuit was created to avoid.  The Court thus concluded that "there is neither 'grave necessity' nor 'special justification' for departing from Cybor."  Slip op. at 26.

"After fifteen years of experience with Cybor, we conclude that the court should retain plenary review of claim construction, thereby providing national uniformity, consistency, and finality to the meaning and scope of patent claims."  Slip op. at 7.

The Federal Circuit then responded to arguments made by the dissent.  The Court first remarked that contrary to the dissent's statement that a substantial proportion of the legal community believed Cybor to have been wrongly decided, all of the technology-industry amicus briefs supported retaining the existing standard of review.  The Court next commented that the dissent offered no superior alternative to de novo review; failed to explain the benefits of abandoning de novo review, with its attendant benefit of intrajurisdictional certainty; and downplayed the gravity of overturning previous en banc decisions in the absence of intervening Supreme Court or legislative action.  The Court also rejected the dissent's reliance on Fed. R. Civ. P. 52(a)(6), which dictates clear-error review of district courts' factual findings, explaining that the rule does not determine what is properly considered a question of fact.  Finally, the Court contested the evidentiary basis for the dissent's argument that the Cybor standard has produced a high reversal rate, and thus added considerable uncertainty and expense to patent litigation, citing data that reversal rates for claim construction match those of other patent-related issues and that there has been a decline in the appeal rate of district court patent cases.

Accordingly, the Federal Circuit confirmed on the basis of stare decisis the Cybor standard of de novo appellate review of claim construction as a matter of law.  

Judge Lourie concurred, joining the majority opinion but writing separately to note additional reasons why retaining Cybor was wise.  First and foremost, according to Judge Lourie, the Supreme Court held that claim construction is a question for the court, not the jury.  Equally important to Judge Lourie was the goal of uniformity in interpreting patent claims, a goal consistent with the purpose of creating the Court and a goal that would be undermined if deference to a district court's determination led to conflicting claim constructions in different cases.  In Judge Lourie's view, claim construction is not a process that normally involves historical facts, but rather primarily involves reading the patent's written description and prosecution history, a process analogous to the interpretation of other legal instruments, such as contracts and statutes.  Moreover, Judge Lourie explained, it was incorrect that the Court did not give any deference to a district court's claim construction since, when asked to construe the claims, the Court notes and considers the district court's construction, and when the Court disagrees, "it is not without a degree of informal deference."  Lourie Concurrence at 5.  Thus, according to Judge Lourie, splitting claim construction into legal and factual issues would threaten uniformity achieved by intensive appellate review and create a complication that ordinarily would not make a difference given proper informal deference.

Judge O'Malley dissented, joined by Chief Judge Rader and Judges Reyna and Wallach, and disagreed that stare decisis justified adhering to the Cybor standard.  Judge O'Malley argued that reversing Cybor would not upset expectations in the legal community as no one believes its validity to be settled, pointing to the debate over Cybor within the Court and among litigants, practitioners, and academics.  Moreover, according to Judge O'Malley, Cybor misapprehends the Supreme Court's decision in Markman v. Westview Instruments, Inc., 517 U.S. 370 (1996), which acknowledged the factual aspects of claim construction, and ignores the realities of the claim construction process, which involves factual issues as acknowledged by both parties, the PTO, and most amici.  Judge O'Malley also argued that Cybor contravenes Rule 52(a)(6), which instructs the Court that findings of fact must not be set aside unless clearly erroneous.  Finally, Judge O'Malley argued that overruling Cybor is justified because of the undesired consequences of refusing to acknowledge the factual aspect of claim construction:  Cybor has made the claim construction process less transparent, accurate, predictable, and efficient, thus undermining the very interests promoted by stare decisis; has increased the cost of litigation by creating incentives to appeal and discouraging settlements; and has failed to promote uniformity or predictability given claim construction's fact-specific nature.  Thus, according to Judge O'Malley, while the ultimate question of claim meaning should remain subject to de novo review, the Court should defer to the district court's factual findings needed to resolve claim construction disputes unless clearly erroneous.

This article previously appeared in Last Month at the Federal Circuit, March, 2014

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