The firm recently won a victory for Shell Oil Company in the U.S. Court of Appeals for the Federal Circuit, affirming a district court ruling that Shell’s process for benzene purification did not infringe the asserted patent claims as a matter of law.
Plaintiff David Netzer Consulting Engineer had sued Shell in the U.S. District Court for the Southern District of Texas, accusing Shell’s benzene-purification process of infringing its patent. Shell’s trial counsel won an early summary judgment of non-infringement—but the district court failed to conduct a formal claim construction analysis and dismissed the case in a two-page summary judgment opinion. Quinn Emanuel was retained to defend this victory on appeal to the Federal Circuit.
On May 27, 2016, the Federal Circuit issued a unanimous precedential opinion adopting the firm’s arguments in full and affirming the judgment of non-infringement. The firm first had to persuade the court to adopt Shell’s construction of the sole contested limitation in the asserted patent claims. Specifically, the claims required “fractionating” an intermediary product (pyrolysis gasoline) to form a purified benzene product of at least 80% benzene. The plaintiff argued that “fractionating” means any kind of separation. The firm persuaded the court that “fractionating” in the patent should be construed to require separating compounds based on “distillation” or boiling-point differentials, not generic separating by any means. The key to persuading the court of this construction was highlighting passages in the patent specification discussing how “fractionation” can be frustrated by “azeotropes,” which are liquid mixtures with a uniform boiling point whose components cannot be separated based on their own differences in boiling point. Writing for the court, Judge Alan Lourie (who holds a Ph.D in chemistry) walked through the firm’s “azeotrope” argument at length, discussing how the azeotrope-based passages in the patent compel a conclusion that, in this patent, “fractionating” is limited to boiling-point separation.
Based on this construction, Judge Lourie and his colleagues (Chief Judge Prost and Judge Taranto) agreed that Shell’s accused process could not infringe as a matter of law because Shell used solubility-based separation, not boiling-point separation, to take its benzene products over the critical 80% purity level.