By Tony Dutra
18 --ButamaxTM Advanced Biofuels LLC will have
another chance to assert patents against isobutanol manufacturer Gevo Inc.
after a Feb. 18 reversal of a district court's summary judgments by the U.S.
Court of Appeals for the Federal Circuit (Butamax(TM) Advanced Biofuels
LLC v. Gevo, Inc., Fed. Cir., No. 2013-1342, 2/18/14).
The court's decision followed from a revised claim construction, where it
held that the patentee's definition of a key term was not as narrow as the
lower court found because evidence about the knowledge of the person of
ordinary skill at the time showed that a broader interpretation was more
In a twist, each party filed patent applications, subsequent
to the ones at issue here, with disclosures likely to hurt their own arguments
Butamax is a joint venture between BP Plc--British
Petroleum--and E. I. du Pont de Nemours and Co. and is assignee of patents
(U.S. Patent Nos. 7,851,188 and 7,993,889) related to isobutanol, which is
useful as a solvent and a gasoline blendstock. Both patents emanate from an
application filed in 2005.
The patents describe a biosynthetic pathway
for the production of isobutanol, including use of “acetohydroxy acid
isomeroreductase [also known as KARI] having the EC number 126.96.36.199.” KARI is
further defined in the specification with reference to the same “Enzyme
Commission” (EC) classification system number. By convention, that system
requires specific identification of cofactors, and EC number 188.8.131.52 only
specifies a cofactor known as NADPH.
Butamax sued Gevo for patent infringement in the U.S. District Court
for the District of Delaware. Judge Sue L. Robinson construed the asserted
claims limiting KARI in terms of the cofactor used. Since Gevo makes isobutanol
using other cofactors, she made additional infringement and invalidity rulings
on summary judgment motions favoring Gevo, and Butamax appealed.
The appeals court, in an opinion
written by Judge Richard Linn, first reversed the claim construction
The court agreed that Butamax had “offered a definition of
KARI” in the specification, but that this definition did not “ 'clearly
express[ ] an intent” to redefine KARI in a way that differs from the plain and
ordinary meaning” of a skilled artisan--that KARI was not limited to NADPH as a
cofactor--quoting CCS Fitness, Inc. v. Brunswick Corp., 288 F.3d 1359,
1366, 62 U.S.P.Q.2d 1658 (Fed. Cir. 2002).
Gevo presented arguments, to
no avail, based on the EC convention for describing cofactors, preferred
embodiments listed in the specification and Butamax's prosecution history. In
part, the alleged infringer was defeated by its own statements and patent
applications. In 2008, it described its own mutant enzymes with reference to
the same EC number and at the same time contended that its enzymes were not
NADPH-dependent. And while the district court discounted Butamax's reliance on
a 1991 reference, Gevo's 2007 patent application cited the same reference for
the proposition that an alternative cofactor could be used.
cited references to “other cofactors where appropriate” in the specification
and relied on another enzyme database that noted the alternative as a
substitute for NADPH. Thus, the court said, the circumstances did not represent
a case where Butamax had acted as its own lexicographer to change the meaning a
skilled artisan would understand.
With the reversal of the claim
construction judgment, most of Gevo's noninfringement arguments were of no
consequence either. However, the court acknowledged that Gevo established at
least one genuine issue of material fact for the district court to reconsider
The lower court found two
claims invalid for inadequate written description in that they claimed
“inactivated genes” to reduce the effect of competing pathways, with no
description of how to inactive genes. And the appeals court was skeptical of
Butamax's arguments that “it was 'conventional' in 2005 to deactivate the
pathway,” seeing in the specification and other references only a desire to do
Ultimately, the court agreed with Butamax, however, that it had
established a genuine dispute of material fact. On the other hand, the
reference Butamax relied on also said that the deactivation “virtually
abolished” isobutanol production. On remand, then, Butamax will have to address
that seeming contradiction.
More problematic for Butamax may be its
subsequently filed continuation-in-part application, which provided additional
detail on the deactivation of certain genes. That at least raised an additional
question of what was known in the art in 2005, the court said.
Nevertheless, the court reversed summary judgment of invalidity for lack of
adequate written description and remanded that aspect of the case for further
development as well.
Chief Judge Randall R. Rader and Judge Evan J.
Wallach joined the opinion.
Leora Ben-Ami of Kirkland & Ellis LLP,
New York, represented Butamax. Michelle S. Rhyu of Cooley LLP, Palo Alto,
Calif., represented Gevo.
Text is available at http://www.bloomberglaw.com/public/document/ButamaxTM_Advanced_Biofuels_v_Gevo_Inc_Docket_No_1301342_Fed_Cir_.
To contact the reporter on this story: Tony Dutra in Washington at firstname.lastname@example.org
To contact the editor responsible
for this story: Naresh Sritharan at email@example.com
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