Lexicography may not override ordinary meaning in the absence of clear disclaimer

Because the district court erred in claim construction, the Fed. Cir. vacates both its denial of infringement summary judgment and its grant of summary judgment of no infringement under the doctrine of equivalents, remanding both for further proceedings. Separate from the claim construction issue, the Fed. Cir. reverses the district court's summary judgment of insufficient written description. Finally, the Fed. Cir. reverses the district court's summary judgment of lack of enablement as a scrivener's error.

Butamax(TM) Advanced Biofuels v. Gevo Inc., ___ F.3d ____ (Fed. Cir. Feb. 18, 2014) (Rader, LINN, Wallach) (D. Del.) (2 of 5 stars)

Claim construction: The patent included an express definition of the term "acetohydroxy acid isomeroreductase" ("KARI") as "an enzyme ... using NADPH." The district court determined that the patentees acted as their own lexicographers, and thus defined "KARI" narrowly as excluding KARI that are not NADPH-dependent. But the Fed. Cir. held that nothing in the intrinsic or extrinsic record worked an express disavowal of the "ordinary" meaning of KARI, which was broader and was not limited to dependence on NADPH. Based on this lack of disclaimer, the Fed. Cir. set forth a broader construction based on this ordinary meaning. The Fed. Cir. then vacated the district court's denial of Butamax's motion for summary judgment of infringement, as well as its grant of Gevo's motion for summary judgment of no infringement under the doctrine of equivalents. The Fed. Cir. rejected one of accused infringer Gevo's noninfringement arguments as unsupported by evidence before the district court, but remanded the remainder.

Written description requirement: The Fed. Cir. also reversed summary judgment of invalidity based on lack of written description, because Butamax had raised a genuine dispute of material fact relating to the description supporting the claims. Accused infringer Gevo argued that Dickinson, a reference cited in the asserted patent and partly relied on by Butamax, was irrelevant to the written description analysis because the patent's citation to it did not concern the disputed description. The Fed. Cir. disagreed and held that Dickinson was part of the germane prior art, and could thus create a material fact question as to whether the patentees had satisfied the written description requirement. Finally, in a related prosecution, the PTO had held that the patent in this appeal "does not teach" the matter in question. Slip op.at 25. The Fed. Cir. declined to find this dispositive for the written description inquiry, as the PTO's examination was for anticipation or obviousness, not for written description.

Enablement: The Fed. Cir. concluded that the district court's judgment that certain claims were invalid for lack of enablement was a scrivener's error, and reversed. Gevo did not defend this judgment on appeal.