Lighting Ballast Control LLC v. Philips Electronics, NA, No. 12-1014 (Fed. Cir. 2015)
Annotate this CaseFluorescent lamp fixtures typically regulate electric current by an electronic ballast, which maintains current levels high enough to start the lamp but prevents current from reaching destructive levels. When a lamp is removed from its holders or when a filament is broken, current provided by the ballast ceases to flow and dissipates back into the ballast, which can destroy the ballast and create an electric shock hazard. LB’s 529 patent discloses an electronic ballast able to shield itself from destructive levels of current. LB sued ULT, asserting infringement. ULT argued that the term “voltage source means” is governed by 35 U.S.C. 112 and that the claims are invalid under 35 U.S.C. 12 as indefinite because the specification fails to disclose what structure corresponded to the “voltage source means” limitation. The district court concluded that the term “voltage source means” had sufficient structure. A jury awarded LB $3 million in damages. The Federal Circuit affirmed, holding that claim construction is an issue of law that it reviews de novo. The Supreme Court remanded for reconsideration in light of its holding in Teva Pharmaceuticals (2015), that while the ultimate question of claim construction is a legal question, there may be underlying “subsidiary” factual findings related to the extrinsic record that are reviewed for clear error. On remand, the Federal Circuit affirmed. Because the district court’s factual findings demonstrate that the claims convey sufficient structure, it was correct to conclude that the term “voltage source means” is not governed by section 112.
This opinion or order relates to an opinion or order originally issued on January 2, 2013.
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