Obviousness is a mixed question of law and fact. Thus,
when a jury reaches a verdict on the issue of obviousness, the
Federal Circuit defers to the jury’s factual findings that
are supported by substantial evidence. Practitioners should
take note when the Federal Circuit overturns a jury’s finding
of obviousness or nonobviousness. These situations, as
demonstrated in the recent case of ABT Systems, LLC v. Emerson
Electric Co., Nos. 2014-1618, -1700 (Fed. Cir. Aug. 19, 2015),
often involve a strong showing of obviousness or nonobviousness
that can highlight how practitioners may invoke or defend against
35 U.S.C. § 103 in their own cases.
The asserted patent in this case, U.S. Patent No. 5,547,017
(“the 017 patent”), titled “Air Distribution Fan
Recycling Control,” is directed to techniques for running an
HVAC system fan intermittently during periods when a thermostat is
not requesting heating or cooling. As described in the
’017 patent, this “recycle control” feature
involves periodic fan operation when the system is not heating or
cooling, where the fan operation begins “a preselected time
period” after the fan stops at the end of a heating or
cooling cycle, or after the termination of a “constant fan
mode” operation. The purported benefits of this
technique, as described in the specification, include reduced air
stagnation, dilution of point sources of indoor air pollution,
improved air cleaning, and reduced energy consumption.
The ’017 patent was assigned from the inventor to the
University of Central Florida, which in turn licensed the patent to
ABT Systems, LLC. The University and ABT sued several
defendants for alleged infringement of the ’017 patent,
including Emerson Electric Co. In particular, they alleged
that the Comfort Circulating Fan Feature of Emerson’s
“Big Blue” thermostat infringed the ’017
patent.
During a jury trial, Emerson challenged the ’017 patent as
being obvious in view of four prior art references. In
particular, Emerson argued that the claims of the ’017 patent
would have been obvious in view of U.S. Patent No. 2,013,136
(“Cornelius”); U.S. Patent No. 4,838,482
(“Vogelzang”); U.S. Patent No. 2,953,908
(“Petrone”); and/or U.S. Patent No. 5,020,332
(“Nakatsuno”). They jury rejected this
invalidity defense and found the asserted claims of the ’017
patent infringed by Emerson. Following the verdict, Emerson
filed a motion for judgment as a matter of law (JMOL) to set aside
the verdict, which the district court denied. Emerson
appealed from the denial of its JMOL motion, and the plaintiffs
also appealed on issues relating to damages.
On appeal, the Federal Circuit held that the district court
erred in denying Emerson’s JMOL motion based on obviousness.
In doing so, the Federal Circuit substantively reviewed the
four prior art references asserted by Emerson and concluded that no
reasonable jury could have found, in light of KSR International
Co. v. Teleflex Inc., 550 U.S. 398 (2007), that the asserted
claims were not obvious.
As described by the Federal Circuit, Cornelius
discloses a furnace air circulation fan that
“intermittently” cycles on and off, using a
“timing device,” when there is no call for heat from a
thermostat. But Cornelius does not expressly teach
the timer being tied to the deactivation of the heating elements,
as recited in claim 1 of the ’017 patent.
Vogelzang discloses an HVAC system with a “cycle
position” option on a thermostat, as well as periodic fan
operation when there is no call for heating or cooling. Like
Cornelius, Vogelzang does not explicitly teach
running a fan periodically based on when heating or cooling
elements are deactivated. Petrone discloses a
control for a fan such that the fan stops when the call for cooling
ends, at which point there is a delay before the fan begins to
operate independent of a call for cooling. This delay occurs
in order to allow sufficient time for water to drain from the
cooling coils, thus preventing moisture from being blown into the
air. Nakatsuno discloses how a fan may be operated
for a “predetermined time Δt1 after the stop of the
compressor.” Further, Nakatsuno teaches that
the fan may also be “intermittently driven” to enhance
comfort and minimize energy consumption.
The Federal Circuit framed the issue of obviousness as being
whether a person of ordinary skill would have combined disclosure
from Petrone and Nakatsuno, regarding
“single-shot” fan operation as a function of the time
when heating or cooling cycles end, with disclosure from
Cornelius and Vogelzang, regarding periodic fan
cycles during periods of time when there is no call for heating or
cooling. The plaintiffs’ expert opined that one could
not simply “plug [ ]” the former references into the
latter, and that there would be “logistical and enablement
issues” if they were combined. ABT Sys., Nos.
2014-1618, -1700, slip op. at 14 (alteration in original) (citation
omitted). On the other hand, Emerson’s expert testified that
“it would have been a logical and ordinary step for a person
of skill in the art to use the prior art to create a periodic fan
that is dependent on the end of a heating or cooling
cycle.” Id. at 14-15. The Federal Circuit
sided with Emerson, relying on the KSR rationale that
“when a patent claims a structure already known in the prior
art that is altered by the mere substitution of one element for
another known in the field, the combination must do more than yield
a predictable result.” Id. at 17 (quoting
KSR, 550 U.S. at 416). According to the Federal
Circuit, the timer of Vogelzang or Cornelius, as
modified by the predetermined and compressor-dependent interval of
Nakatsuno or Petrone, would have yielded a
predictable result, namely, “the system fan would activate
periodically following the end of a heating or cooling
cycle.” Id.
The Federal Circuit further explained that, even if the
references themselves do not provide a motivation to combine their
teachings, a court “may find a motivation to combine prior
art references in the nature of the problem to be
solved.” Id. at 18 (quoting Ruiz v. A.B.
Chance Co., 357 F.3d 1270, 1276 (Fed. Cir. 2004)).
Accordingly, based on Vogelzang and the nature of its
“problem to be solved,” it would have been
“nearly obvious from that disclosure itself to set the
periodic fan to run as a function of when the heating or cooling
cycle ended.” Id.
Having found that Emerson raised a prima facie case of obviousness, the Federal Circuit also considered the plaintiffs’ evidence of purported secondary considerations of nonobviousness, including commercial success and long-felt need. As the Federal Circuit found, this evidence could not rebut the showing of obviousness since there was no evidence of a “nexus” between the alleged secondary considerations and the claimed invention.
While ABT Systems involved a litigation appeal, its application of obviousness rationales is instructive for those involved in drafting or prosecuting patent applications. Practitioners should appreciate how strong an obviousness position may be even where there is no express teaching in the references to combine them in the manner recited in the challenged claims. Indeed, in ABT Systems, the obviousness position was so strong that the Federal Circuit was willing to overturn the jury’s finding of nonobviousness, which involved factual determinations to which the Federal Circuit had to “assign due deference.” Id. at 11. At the same time, practitioners should note that, in ABT Systems, “all of the claimed limitations [we]re expressly found in the cited prior art references.” Id. at 21. Thus, ABT Systems did not involve a situation where the obviousness rationale left a “gap” that was to be filled in by “common knowledge” or other undisclosed teachings. Thus, for situations involving such gaps, practitioners still have a range of arguments at their disposal to attack the underlying obviousness rationale.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.