Low Temp Industries, Inc. v. Duke Manufacturing Co.

N OTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
LOW TEMP INDUSTRIES, INC.,
Plaintiff-Appellee
v.
DUKE MANUFACTURING CO.,
Defendant-Appellant
______________________
2021-2137
______________________
Appeal from the United States District Court for the
Eastern District of Missouri in No. 4:20-cv-00686-MTS,
Judge Matthew T. Schelp.
______________________
Decided: December 28, 2021
______________________
D AVID CLAY H OLLOWAY , Kilpatrick Townsend & Stock-
ton LLP, Atlanta, GA, argued for plaintiff-appellee. Also
represented by COURTNEY D ABBIERE , RICHARD W.
G OLDSTUCKER; K ATHLEEN G EYER , Seattle, WA,
K EVIN D ONALD C ONNEELY , Stinson LLP, Minneapolis,
MN, argued for defendant-appellant.
______________________
Before D YK, T ARANTO, and CHEN, Circuit Judges.
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 2
CHEN, Circuit Judge.
Duke Manufacturing Co. (Duke) appeals the entry of a
preliminary injunction related to its products accused of
patent infringement by Low Temp Industries, Inc. (LTI).
The district court found that LTI is likely to show that
Duke’s accused products infringe several claims of U.S. Pa-
tent Nos. 8,307,761 (’761 patent) and 8,661,970 (’970 pa-
tent), and that Duke had failed to raise a substantial
question of validity as to those claims based on the Fi-
negan1 reference. Because the district court relied on an
erroneous claim construction and misread the Finegan ref-
erence, it failed to recognize that Duke raised a substantial
question as to the validity of the relevant claims. We re-
verse.2
BACKGROUND
A
LTI owns U.S. Patent Nos. 8,307,761 (’761 patent) and
8,661,970 (’970 patent),3 which relate to multi-well food
presentation modules—essentially, a buffet where hot food
in one well can be next to cold food in another well. See
’761 patent at Abstract, col. 1 ll. 6–13. According to the
common patent specification, prior art food presentation
equipment, whether a serving bar or some other device, “is
dedicated to heating or to cooling food contained therein.”
Col. 1 ll. 34–35; Id. at ll. 43–44 (describing prior art serving
bar as “dedicated to heating or to cooling all wells.”). The
specification further explains that it can be “undesirable”
for dine-in, self-service restaurants with multi-well food
bars to have all the wells at the same temperature. Id. at
ll. 55–58. The patents claim to solve what they describe
1 PCT Pub. No. WO 2000/71950 (Finegan).
2 Duke’s motion to stay the preliminary injunction
pending appeal is hereby denied as moot.
3 The patents share a common specification.
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 3
as the “taco-presentation type problem” such that “ambi-
ent-temperature items (such as tortilla shells), heated
items (such as meat), and refrigerated items (such as let-
tuce and cheese)” can be displayed together and in adjacent
wells in the same food bar. ’761 patent at col. 2 ll. 24–28.
To accomplish this goal, “[e]ach well is isolated thermally
from adjacent wells and has an independently controlled
heating and cooling system.” Id. at ll. 32–33. The specifi-
cation explains that “pipes 40,” which can carry refriger-
ant, are in contact with the sidewalls of a well and a
“heating mechanism” is located below the well floor. Id.,
col. 4 ll. 29–53.
Claims 1–4 of the ’761 patent are representative and
are reproduced in part below:
1. A food presentation module generally immobile
in use, comprising:
a. a frame;
b. adjacent first and second wells for receiving con-
tainers of bulk food, each well being individually
insulated and thermally isolated from an adjacent
well via interior walls and exterior walls forming
insulative air gaps therebetween . . .; and
c. a temperature-control system for controlling
temperatures of the first and second wells inde-
pendently . . . such that both wells may be refriger-
ated, both wells may be heated, or the first or
second well may be refrigerated while the other of
the first or second well is heated.
2. A module according to claim 1 in which the tem-
perature-control system is configured to allow food
received in the first well alternately to be heated to
a temperature substantially above ambient.
3. A module according to claim 2 in which the tem-
perature-control system is configured to allow food
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 4
received in the second well alternately to be refrig-
erated to a temperature substantially below ambi-
ent.
4. A module according to claim 1, further compris-
ing one or more additional wells for receiving a con-
tainer of food and in which the temperature-control
system controls temperature of the one or more ad-
ditional wells independently of temperatures of the
first and second wells.
’761 patent at claims 1–4.
B
Finegan discloses a food service display that can be
used as “an open-topped styled self service food bar [ ] or
buffet unit [ ] for maintaining food at a desired tempera-
ture.” Id. at 5, FIG. 1. Cooling coils are mounted along the
sidewalls of a pan and a heating element is located beneath
the pan. Id. at 3, FIG. 1. The pan in Finegan’s Figure 1
embodiment can be operated “in a heating mode or a cool-
ing mode.” See id. at 5.
Finegan’s Figure 7, reproduced below, shows an alter-
native embodiment with “multiple pans 18A, 18B.” See id.
at 8, FIG. 7. This embodiment includes “[o]ne control sys-
tem [controller 80 plus sensors that] allow[] the user to
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 5
control the temperature of two pans [18A, 18B] inde-
pendently. For example, one pan could be hot and the other
pan could be cold.” Id. at 9–10.
C
LTI and Duke are competitors in the market for food
presentation modules that can maintain adjacent food
wells at different temperatures. LTI was first to market,
having developed its QuickSwitch product in 2007. LTI ap-
plied for patent protection in 2008 which resulted in the
’761 and ’970 patents.
LTI initially sold its QuickSwitch product as a part of
its own counters. In 2012, LTI began offering QuickSwitch
through distributors as a drop-in option for its customers’
counters. Duke was one such customer.
In 2019, Duke approached LTI about buying the Quick-
Switch product directly from LTI instead of through a dis-
tributor; LTI declined. Duke then brought a competing
Hot-Cold-Freeze (HCF) product to market in 2020. This
patent infringement suit followed.
LTI moved for a preliminary injunction enjoining Duke
from activities related to its allegedly infringing competing
products. See Low Temp Indus., Inc. v. Duke Mfg. Co., No.
4:20-CV-00686-MTS, 2021 WL 2634671, at *1 (E.D. Mo.
June 25, 2021) (PI Order). The district court found that
each of the four preliminary injunction factors—(1) the
probability that the movant will prevail on the merits; (2)
the threat of irreparable harm to the movant; (3) the bal-
ance between that harm and the harm that granting the
injunction will inflict on other parties; and (4) the public
interest—weighed in favor of granting an injunction. See
id. at *3.
The district court performed the required two-part
analysis for likelihood of success on the merits. See id. at
*4 (“To demonstrate a likelihood of success on the merits,
LTI must show that (1) it will likely show that Duke’s HCF
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 6
infringes any one of the Asserted Patents, and (2) its in-
fringement claims ‘will likely withstand [Duke’s] chal-
lenges to the validity and enforceability of the [Asserted
Patents].’” (alterations in original)). As to infringement,
the district court determined that LTI is likely to show at
trial that Duke’s competing product infringes claims 3, 4,
9, 10, 13, 15, and 16 of the ’761 patent and claim 8 of the
’970 patent (the Infringed Claims). See id. at *7. Central
to that finding was the district court’s construction of the
claim term “insulative air gaps” or “insulative gaps” to not
exclude a gap filled with insulation. See id. at *6.4
As to Duke’s validity challenge, Duke asserted that the
Infringed Claims were either anticipated by Finegan or
rendered obvious by Finegan in view of one or more second-
ary references. Duke’s invalidity theories accounted for the
district court’s claim construction. For example, Duke con-
tended that, if the district court found “insulative air gaps”
included gaps filled with insulation, then Finegan was an-
ticipatory for all but claim 4 of the ’761 patent. If, on the
other hand, the district court limited “insulative air gaps”
to exclude gaps filled with insulation, Duke’s challenge was
one of obviousness based on Finegan and a secondary ref-
erence containing a gap without insulation.
The district court found Duke’s anticipation arguments
unpersuasive because Duke’s expert stated that Finegan
disclosed only “the vast majority of claimed features” and
because Duke based its anticipation case in part on a le-
gally incorrect “point of novelty” theory. See id. at *8 &
n.12. The district court did not address whether or how its
construction of “insulative air gaps” affected Duke’s inva-
lidity theories.
4 Duke does not challenge the district court’s claim
construction or preliminary infringement determination on
appeal.
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 7
The district court then found that a skilled artisan
would not have considered the Infringed Claims obvious
based on Finegan. See id. at *9. The district court con-
cluded there were “meaningful and relevant” differences
between Finegan and the Infringed Claims. See id. The
district court focused on Finegan’s goal of providing frost-
ing on the pan’s flanges and Finegan’s use of a hot water
bath to heat the individual pans. See id. Ultimately, the
district court concluded that:
Finegan does not . . . disclose or teach two ther-
mally isolated and insulated ‘pans’ within a single
module that can be operated at different tempera-
tures simultaneously. Nor would it be obvious to
modify Finegan to arrive at the Asserted Patents,
given Finegan’s incorporation of thermally conduc-
tive material, emphasis on frosting, and its descrip-
tion of a single-temperature, one-pan module.
Id.
The district court also found that objective indicia of
nonobviousness supported its conclusions that the In-
fringed Claims were nonobvious. See id. at *10–11.
Namely, LTI presented evidence of commercial success and
that Duke copied LTI’s HCF technology. See id.
Duke timely appealed the district court’s entry of a pre-
liminary injunction and specifically its finding that Duke
failed to raise a substantial question of validity. We have
jurisdiction pursuant 28 U.S.C. § 1292(c)(1).
D ISCUSSION
A
Both the Eighth Circuit and the Federal Circuit review
the grant or denial of a preliminary injunction for abuse of
discretion. See Dixon v. City of St. Louis, 950 F.3d 1052,
1055 (8th Cir. 2020); Titan Tire Corp. v. Case New Holland,
Inc., 566 F.3d 1372, 1375 (Fed. Cir. 2009). “Abuse of
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 8
discretion is a deferential standard of review that requires
a showing that ‘the court made a clear error of judgment in
weighing relevant factors or exercised its discretion based
upon an error of law or clearly erroneous factual findings.’”
Titan Tire, 566 F.3d at 1375 (quoting Genentech, Inc. v.
Novo Nordisk, A/S, 108 F.3d 1361, 1364 (Fed. Cir. 1997)).
“In seeking a preliminary injunction, the patentee has
the burden to show a likelihood of success regarding the
patent's validity; if the accused infringer raises ‘a substan-
tial question regarding validity,’ the district court should
find that the patentee has not shown a likelihood of success
on the merits.” E.I. du Pont de Nemours & Co. v. MacDer-
mid Printing Sols., L.L.C., 525 F.3d 1353, 1358 (Fed. Cir.
2008). “The burden on the accused infringer to show a
substantial question of invalidity at the preliminary in-
junction stage is lower than what is required to prove inva-
lidity at trial.” Tinnus Enterprises, LLC v. Telebrands
Corp., 846 F.3d 1190, 1205 (Fed. Cir. 2017) (quoting Altana
Pharma AG v. Teva Pharm. USA, Inc., 566 F.3d 999, 1006
(Fed. Cir. 2009)). “Vulnerability is the issue at the prelim-
inary injunction stage, while validity is the issue at trial.”
Amazon.com, Inc. v. Barnesandnoble.com, Inc., 239 F.3d
1343, 1359 (Fed. Cir. 2001).
“Where the alleged infringer attacks the validity of the
patent, ‘the burden is on the challenger to come forward
with evidence of invalidity,’ which the patentee must then
rebut.” Tinnus, 846 F.3d at 1205 (quoting Titan Tire, 566
F.3d at 1377–78). “[I]f the trial court concludes there is a
‘substantial question’ concerning the validity of the patent,
meaning that the alleged infringer has presented an inva-
lidity defense that the patentee has not shown lacks sub-
stantial merit, it necessarily follows that the patentee has
not succeeded in showing it is likely to succeed at trial on
the merits of the validity issue.” Titan Tire, 566 F.3d at
1379.
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 9
As explained below, the district court abused its discre-
tion in determining that Duke had not raised a substantial
question of validity as to the Infringed Claims.
B
The district court initially erred by not considering the
impact of its construction of “insulative air gap” to Duke’s
invalidity challenges. The district court was correct that
Duke’s expert stated at one point that “Finegan discloses
the vast majority of claimed features” and that “minor
other features . . . are found in secondary references.” PI
Order at *8 (citing J.A. 1067). But Duke’s expert made that
statement with the caveat that, for each of the Infringed
Claims except for claim 4 of the ’761 patent, a secondary
reference was required only “[t]o the extent ‘air gaps’ or ‘air
gap’ (required for each of the Asserted Claims) is construed
to exclude foam.” See J.A. 1067; see also J.A. 1075 (Duke’s
expert stating that “[i]f ‘air gaps’ is interpreted . . . to cover
insulation material (e.g., foam) between the walls, Finegan
meets [this] element.”). Since the district court construed
“insulative air gap” as not excluding foam, Duke’s invalid-
ity challenges for all but one of the Infringed Claims are
based on anticipation by Finegan. See J.A. 1067–68.
When properly viewed, Duke’s anticipation challenges
to claims 3, 9, 10, 13, 15, and 16 of the ’761 patent and claim
8 of the ’970 patent raise a substantial question of validity.
Anticipation “under 35 U.S.C. § 102 requires that a prior
art reference disclose every limitation of the claimed inven-
tion, either explicitly or inherently.” CommScope Techs.
LLC v. Dali Wireless Inc., 10 F.4th 1289, 1295 (Fed. Cir.
2021). LTI has not contested that Finegan’s Figure 7 dis-
closes two temperature-controlled wells that can be oper-
ated at different temperatures (one hot and one cold) or
that Finegan discloses the other required elements of the
claims (except for claim 4). LTI only disputes whether Fi-
negan’s wells in Figure 7 are “adjacent” to each other
within a single module. See Appellee’s Br. 49–53.
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 10
The district court clearly erred in finding no substan-
tial merit as to whether Finegan discloses the adjacent
wells limitation because (i) the court relied on an overly
narrow understanding of “adjacent,” and (ii) it did not fully
account for Finegan’s alternative embodiment disclosed in
Figure 7 and its corresponding description. First, the dis-
trict court appeared to understand the claims as requiring
Finegan, for anticipation purposes, to teach “two immedi-
ately adjacent pans within a single module that can be
maintained at different temperatures,” PI Order at *9 (em-
phasis added), even though the claims require the wells to
be simply “adjacent.” While the district court did not ex-
plicitly say so, both parties state that the district court
adopted LTI’s argument that the adjacency limitation re-
quires the wells to touch. See Appellant’s Br. 45; Appellee’s
Br. 49. And that Finegan could not disclose touching wells
(i.e., immediately adjacent wells) because its protruding
flanges are thermally conductive, and a hot flange in con-
tact with a cold flange would destroy Finegan’s goal to pro-
vide the “attractive feature” of “frosting” or a “frost top” for
a cold food well, which “give[s] the appearance of the food
such as salad or additional condiments resting in ice.” See
Finegan at 1; PI Order at *9. But this constricted under-
standing of “adjacent” is at odds with the patents’ disclo-
sure, which describes a “distance D1” “between adjacent
wells,” “with D1 preferably being approximately three
inches.” ’761 patent col. 3 ll. 46–52. Given the specification
explicitly states that adjacent wells preferably have a dis-
tance between them (and not defined to be bounded by a
particular outer distance), the basis for the district court’s
finding that Finegan’s pans 18A and 18B are not adjacent,
or next to, each other—because Finegan’s cold pan calls for
frosted flanges—cannot be sustained.
At this stage of the proceeding and on this record, Duke
has sufficiently raised a substantial question that Finegan
anticipates all of the Infringed Claims except for claim 4,
including disclosure of the adjacency limitation. Finegan’s
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 11
Figure 7 discloses a single “apparatus 10” with two wells
18A and 18B that are independently temperature con-
trolled by “one control system.” Finegan at 8, 9. Those
wells are shown within a single countertop 14. Though Fi-
negan does not disclose any particular measured distance
between its wells, neither the district court nor LTI pro-
vides any explanation as to why a disclosure of two wells
within a single apparatus (with no other components dis-
posed within the countertop) are not adjacent under a
proper understanding of that term.
And to the extent that the district court implicitly
found that Finegan’s Figure 7 only discloses a single pan in
each of two separate modules, its order fails to explain the
basis for that finding as well.5 In sum, on this record, we
conclude that the district court abused its discretion in con-
cluding that Duke failed to raise a substantial question of
validity as to claims 3, 9, 10, 13, 15, and 16 of the ’761 pa-
tent and claim 8 of the ’970 patent. Titan Tire, 566 F.3d at
1379.
C
Duke’s challenge to the remaining Infringed Claim,
claim 4 of the ’761 patent, is grounded in obviousness under
the district court’s claim construction. Dependent claim 4
requires one or more additional wells that are inde-
pendently temperature controlled. See ’761 patent at claim
4. Duke acknowledged that Finegan’s two-well disclosure
does not meet this limitation but argued that additional
wells would have been obvious in light of Finegan alone,
see J.A. 1080, and that several other references, including
5 We also note, contrary to the district court’s conclu-
sion, that the type of heating mechanism Finegan uses is
of no moment because the claims do not require a particu-
lar heating scheme.
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 12
the Safyan6, Hansen7, and Shei8 references, teach three or
more independently temperature-controlled wells, see J.A.
1067, 1082–83, 2269–71, 2275–76, 2279–81, 2283–84.
We limit our analysis to Finegan in light of Safyan.
Safyan discloses a “chill-hot buffet tray” with “[a] pair of
heating and cooling units,” Safyan col. 3 ll. 13–20, and that
each unit receives a pan of food, see id. at col. 2 ll. 58–59.
Safyan is not limited to two temperature-controlled pans,
however. See id. at col. 3 ll. 46–49 (“It is to be understood
that one or more than two pairs of aligned openings may be
provided to accommodate as few or as many heating and
cooling units as may be required or desired.”); see also id.
at col. 1 ll. 61–63 (“Multiple temperature controlled units
supported in similar openings may be used for heating
and/or cooling different foods.”).
The district court addressed Finegan in light of Safyan
but limited its analysis to whether Duke improperly relied
on hindsight to argue that the references rendered obvious
two wells within the same food bar that simultaneously al-
low the display of hot and cold foods. See PI Order at *11.
As we determined above, Duke made the requisite show-
ing, for purposes of opposing the preliminary injunction
motion, that Finegan discloses this feature. Thus, the dis-
trict court’s hindsight finding fares no better.
At the district court, Duke argued that a skilled artisan
would have been motivated to add additional wells to Fi-
negan generally and, further, in light of Safyan’s disclosure
of more than two wells. See J.A. 1080 (“[I]n view of Finegan
alone, it would have been obvious to [a skilled artisan] to
add a third and fourth well.”), 1080–81 (arguing a skilled
artisan “would have found it obvious to modify Finegan's
6 U.S. Patent No. 5,941,077 (Safyan).
7 U.S. Patent No. 5,961,866 (Hansen).
8 PCT Pub. No. WO 2008/127330 (Shei).
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 13
food bar to have three, four, or even more wells (for holding
additional pans of food) that are all independently control-
lable with respect to each other” in light of Safyan’s disclo-
sure); see also J.A. 2275–76 (same).
LTI responded that a skilled artisan would not modify
Finegan to include additional wells because “[t]he mechan-
ical design, heat transfer, and fitment in the Safyan Refer-
ence are distinctly different from the mechanical design
described and disclosed in the asserted claims” and thus a
skilled artisan “would not look to the teaching of Safyan to
teach the three or more well system of the Asserted Patents
because Safyan does not consider or teach how refrigera-
tion would occur in a three or more well system.” See Low
Temp Indus., Inc. v. Duke Mfg. Co., No. 4:20-CV-00686-
MTS, ECF No. 43-3 at 32, ¶ 103; see also Appellee’s Br. 28
(“Safyan . . . disclose[s] mechanical designs, mechanisms of
heat transfer and fitment that are different from both Fi-
negan and the Asserted Patents.”). LTI’s argument is not
responsive to Duke’s position. Duke did not argue that a
skilled artisan would incorporate Safyan’s heating and
cooling units into Finegan or that a skilled artisan would
add one of Safyan’s units to arrive at a third well in Fi-
negan. Rather, Duke argued that a skilled artisan would
modify Finegan to include a third (or more) of Finegan’s
wells. See J.A. 2275–76 (“With the idea of adding a third
well (or as many as desired or required) introduced by
Safyan, additional wells to the food bar of Finegan would
have been no more than a duplication of [Finegan’s] parts
according to [Finegan’s] methods.”). Duke’s evidence to
modify Finegan to arrive at claim 4 therefore stands unre-
butted.
We next consider the objective indicia of nonobvious-
ness presented by LTI. See WBIP, LLC v. Kohler Co., 829
F.3d 1317, 1328 (Fed. Cir. 2016) (“[O]bjective considera-
tions of non-obviousness must be considered in every
case.”). The district court found that significant evidence
supported a finding that Duke copied LTI’s product. See PI
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 14
Order at *10. The district court also found that LTI had
presented evidence of commercial success of its Quick-
Switch unit. See id. at *11.
Without commenting on the sufficiency of LTI’s objec-
tive indicia evidence, our determination that Duke has
made a sufficient showing, at this stage, that Finegan an-
ticipates all of the Infringed Claims (except for claim 4) ren-
ders LTI’s objective indicia irrelevant as to those claims.
See Cohesive Techs., Inc. v. Waters Corp., 543 F.3d 1351,
1364 (Fed. Cir. 2008); In re Fracalossi, 681 F.2d 792, 796
(C.C.P.A. 1982) (concurring opinion) (“[Objective indicia]
relevant to a case of prima facie obviousness are not con-
sidered for purposes of determining anticipation.”). As for
claim 4, LTI did not tie any objective indicia to the presence
of three or more wells, or to additional wells in combination
with the features that, there is substantial reason to be-
lieve on this record, are disclosed by Finegan. At the dis-
trict court, LTI instead tied its objective indicia evidence to
the feature of multiple wells in the same food presentation
module where the module can heat and cool foods at the
same time. See Low Temp Indus., Inc. v. Duke Mfg. Co.,
No. 4:20-CV-00686-MTS, ECF No. 43-3 at 55, ¶ 193; id. at
56, ¶ 194; id. at 56, ¶ 195. Thus, we conclude that at this
preliminary stage, LTI failed to present sufficient evidence
of a nexus between any objective indicia and claim 4 of the
’761 patent. See Rambus Inc. v. Rea, 731 F.3d 1248, 1257
(Fed. Cir. 2013) (“[O]bjective evidence of nonobviousness
lacks a nexus if it exclusively relates to a feature that was
known in the prior art.”) (citation omitted).
On the current record, we conclude the district court
abused its discretion in determining that Duke failed to
raise a substantial question of validity as to claim 4 of the
’761 patent.
CONCLUSION
We have considered LTI’s remaining arguments and
find them unpersuasive. For the reasons set forth above,
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LOW TEMP INDUSTRIES, INC. v. DUKE MANUFACTURING CO. 15
we reverse the district court’s entry of a preliminary in-
junction against Duke.
REVERSED
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