In its seminal Markman decision, the Supreme Court sought to usher in a more effective, transparent patent litigation regime through its ruling that “the construction of a patent, including terms of art within its claim, is exclusively within the province of the court.” In the aftermath of this decision, the Federal Circuit adhered to its prior holding that claim construction is a “purely legal issue” subject to plenary de novo review, downplaying the Supreme Court’s more nuanced description of claim construction as a “mongrel practice” merely “within the province of the court.” Over nearly two decades of experience in the post-Markman era, it has become apparent that the Federal Circuit’s adherence to its plenary de novo appellate review standard has frustrated district courts’ distinctive capabilities to apprehend and resolve the factual disputes inherent in claim construction determinations, undermined the transparency of the claim construction process, discouraged detailed and transparent explanations of claim construction reasoning, and produced unusual and at times alarming levels of appellate reversals. These effects have cast doubt on the predictability of patent litigation, discouraged settlements, delayed resolution of patent disputes, and run up the overall costs of patent litigation. Drawing on the Supreme Court’s decision, this brief advocates a balanced, structurally sound, legally appropriate, hybrid standard of appellate review that would promote more accurate and efficient patent dispute resolution. Factual determinations underlying claim construction rulings should be subject to the “clearly erroneous” standard of review, while the Federal Circuit should retain de novo review over the ultimate claim construction decision. In this manner, district court judges, in their capacity as fact-finders, could better surmount the distinctive challenges posed by the technical, mixed fact/law controversies inherent in patent claim construction.
Anderson, Jonas; Menell, Peter; and Rai, Arti, "Taming the Mongrel: Aligning Appellate Review of Claim Construction with its Evidentiary Character in Teva v. Sandoz" (2014). Working Papers. 47.