The Federal Circuit has adopted a practice of reviewing district court patent claim interpretations without deference, applying de novo review, reasoning that patent claim construction is a legal issue. Cybor Corp. v. FAS Technologies, Inc., 138 F.3d 1448, 1465 (Fed. Cir. 1998). This practice has been controversial, since following the Markman decision, Markman v. Westview Instruments, Inc., 517 U.S. 370 (1996), district courts have considered enormous amounts of evidence in crafting claim construction decisions, and generally hold evidentiary “Markman” hearings. Some commentators have argued that because claim construction almost invariably requires the district court to sift through disputed facts, the courts' determinations should be entitled to some deference. For example, in Phillips v. AWH Corp., 415 F.3d 1303, 1334-35 (Fed. Cir. 2005)(en banc), Circuit Judge Mayer famously criticized the court's careful claim construction methodology by noting that the real problem was lack of deference to the trial court's efforts, complaining that the majority decision was "akin to rearranging the deck chairs on the Titanic—the orchestra is playing as if nothing is amiss, but the ship is still heading for Davey Jones' locker.”
On Friday, the Federal Circuit ordered en banc argument on the question of deference to district court claim construction orders. In Lighting Ballast Control LLC v. Philips Electronics North America Corp, No. 2012-1014 (May 15, 2013), the court ordered additional briefs on the following issues:
a. Should this court overrule Cybor Corp. v. FAS Technologies, Inc., 138 F.3d 1448 (Fed. Cir. 1998)?
b. Should this court afford deference to any aspect of a district court’s claim construction?
c. If so, which aspects should be afforded deference?
The court's full order is HERE.