The Supreme Court holds that clear error is the correct standard of review for underlying factual disputes in claim construction
On January 20, 2015, the U.S. Supreme Court issued a decision in Teva Pharmaceuticals USA, Inc. v. Sandoz, Inc. holding that “clear error,” not “de novo,” is the correct standard of appellate review for underlying factual disputes in construing patent claims. However, the ultimate question of claim construction will remain a legal question subject to de novo review by the Federal Circuit.
Here are our “quick takes” on the Supreme Court’s decision:
What changed? The Supreme Court held that the Federal Circuit must apply a “clear error” standard when reviewing a district court’s determination of factual matters in claim construction. Thus, the district court’s factual conclusions that support a claim construction ruling will be given substantial deference on appeal.
What stayed the same? The Supreme Court reaffirmed that the ultimate issue of claim construction is an issue of law, and that a district court’s ultimate determination on claim construction will be reviewed “de novo” (new) by the Federal Circuit.
How does this impact patent cases going forward?
Status quo in some cases: In cases where the district court only reviews intrinsic evidence to the patent (i.e., the claims and specification, along with the patent’s prosecution history), the result is considered a determination of law, and will be subject to de novo review on appeal (i.e., no deference to the district court).
“Game changer” in other cases: In cases where the district court looks beyond the patent’s intrinsic evidence and consults extrinsic (outside) evidence to understand, for example, the background science or the meaning of a claim term in the relevant art during the relevant time period, the “evidentiary underpinnings” of claim construction will be reviewed for clear error on appeal. Thus, the Supreme Court’s decision may make it tougher to get certain claim construction decisions overturned on appeal. This will likely put increased emphasis on “winning” the factual determination of claim construction at the district court level.
How does the Supreme Court’s decision impact the Teva case?
At the district court, the judge weighed conflicting expert evidence, and concluded that the claim term “molecular weight” was sufficiently definite and the patent was thus valid. On appeal, the Federal Circuit rejected the district court’s factual findings and found the patent invalid. On remand, in view of the Supreme Court’s decision, the Federal Circuit must accept the district court’s factual findings unless they are “clearly erroneous.”
To read the Supreme Court’s decision, click here.