May 27, 2016

Consistent Usage and Disclaimer in Intrinsic Record Trump Anything in Extrinsic Record

By Bryan K. Wheelock, Principal

In David Netzer Consulting Engineer LLC, v. Shell Oil Company, [2015-2086] (May 27, 2016), the Federal Circuit affirmed summary judgment of non-infringement of U.S. Patent 6,677,496 on a process for the coproduction of ethylene and purified benzene.

At issue was the meaning of the term “fractionating” in the claims.  The Federal Circuit noted that the district court did not make any factual findings to support its claim construction, but found that because the intrinsic record alone determines the proper construction in this case, it was able to conduct its review adequately, de novo.

Claim terms are generally given their ordinary and customary meaning as understood by a person of ordinary skill in the art at the time of the invention.  Because that meaning is often not immediately apparent, and because patentees frequently use terms idiosyncratically, the court looks to the intrinsic record, including “the words of the claims themselves, the remainder of the specification, the prosecution history, as well as to extrinsic evidence when appropriate, to construe a disputed claim term.

The patent owner argued that fractionizing simply meant separating, but the Federal Circuit disagreed, finding that fractionating means separating compounds based on differences in boiling points.  The Federal Circuit noted that the specification repeatedly and consistently uses “fractionating” or “fractionation” to describe separating petrochemicals based on boiling point differentials. Moreover, the Federal Circuit noted, the patentee made clear and unmistakable statements in the intrinsic record, distinguishing the claimed invention from and disclaiming conventional extraction.

The Federal Circuit also rejected conflicting extrinsic evidence cited by the parties, explaining that extrinsic evidence may not be used to contradict claim meaning that is unambiguous in light of the intrinsic record.

Having affirmed the claim construction, the Federal Circuit likewise affirmed summary judgment of noninfringement, adding that disclaimer applied to both literal infringement and to infringement under the doctrine of equivalents.