North Star Technology International Ltd., North Star Technology Ltd. v. Latham Pool Products, Inc.

N OTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
NORTH STAR TECHNOLOGY INTERNATIONAL
LTD., NORTH STAR TECHNOLOGY LTD.,
Plaintiffs-Appellants
v.
LATHAM POOL PRODUCTS, INC.,
Defendant-Appellee
______________________
2023-2138
______________________
Appeal from the United States District Court for the
Eastern District of Tennessee in No. 3:19-cv-00120-KAC-
DCP, Judge Katherine A. Crytzer.
______________________
Decided: April 24, 2025
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MATTHEW J AMES D OWD, Dowd Scheffel PLLC, Wash-
ington, DC, argued for plaintiffs-appellants. Also repre-
sented by ROBERT J AMES SCHEFFEL ; MICHAEL J. BRADFORD,
WADE R. O RR , Luedeka Neely, P.C., Knoxville, TN; P ERRY
SAIDMAN, Perry Saidman, LLC, Miami Beach, FL.
RUSSELL K ORN, Kilpatrick Townsend & Stockton LLP,
Atlanta, GA, argued for defendant-appellee. Also
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NORTH STAR TECHNOLOGY INTERNATIONAL LTD. v.
LATHAM POOL PRODUCTS, INC.
2
represented by MICHAEL A. BERTELSON, COURTNEY
D ABBIERE ; MEGAN ELIZABETH BUSSEY , New York, NY.
______________________
Before L OURIE, CHEN, and HUGHES , Circuit Judges.
HUGHES , Circuit Judge.
North Star Technology International Limited and
North Star Technology Limited (collectively, North Star)
sued Latham Pool Products, Inc. in the U.S. District Court
for the Eastern District of Tennessee for alleged infringe-
ment of a design patent related to swimming pools. The
district court granted Latham’s motion for summary judg-
ment of non-infringement, reasoning that Latham’s pool is
plainly dissimilar to North Star’s design patent. We find no
reversible error in the district court’s determinations and
affirm its grant of summary judgment of non-infringement.
I
North Star owns and manufactures products that prac-
tice U.S. Design Patent No. D791,966 which claims the or-
namental appearance of a swimming pool. The D’966
patent was filed on, and thus has a priority date, of Janu-
ary 28, 2016. J.A. 21. Latham manufactures and sells a fi-
berglass swimming pool it brands as the Corinthian 16. As
seen in the depiction below, both the D’966 patent (on the
left) and the accused Corinthian 16 design (on the right)
relate to rectangular swimming pools with tanning ledges.
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NORTH STAR TECHNOLOGY INTERNATIONAL LTD. v.
LATHAM POOL PRODUCTS, INC.
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D’966 patent, Fig. 1 and
Fig. 7
Latham’s accused product,
the Corinthian 16
In April 2019, North Star filed a complaint against Lat-
ham, alleging infringement of its D’966 Patent. J.A. 45–52.
Latham filed a motion for summary judgment of non-in-
fringement, arguing that the designs are plainly dissimilar
and that “any similarities that do exist between the D’966
Patent and Corinthian 16 designs stem from their use of
design elements that were commonly used in pool designs
before the D’966 Patent.” J.A. 532. The district court
agreed, explaining that the “prominent ornamental ele-
ments of the two designs”—including the shape of the entry
steps and deep end benches—“differ significantly, creating
an overall ‘plainly dissimilar’ appearance.” J.A. 18 (inter-
nal citation omitted). It added that a review of the prior art
confirmed non-infringement because “[e]ach of the perti-
nent design elements included in the D’966 Patent and Co-
rinthian 16 . . . existed before [North Star] filed the D’966
Patent.” J.A. 19 (emphasis added). The district court cited
to examples of pools with rectangular tanning ledges that
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NORTH STAR TECHNOLOGY INTERNATIONAL LTD. v.
LATHAM POOL PRODUCTS, INC.
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pre-date the D’966 Patent, see J.A. 5–9, as well as to Lat-
ham’s own use of the same deep end benches used in the
Corinthian 16 in its older pool models.
The district court entered final judgment dismissing
North Star’s claims on June 6, 2023. J.A. 1. North Star
timely appealed, and we have jurisdiction under 28 U.S.C.
§ 1295(a)(1).
II
We follow regional circuit law when reviewing a dis-
trict court’s grant of summary judgment. Adasa Inc. v.
Avery Dennison Corp., 55 F.4th 900, 907 (Fed. Cir. 2022).
The Sixth Circuit reviews a grant of summary judgment de
novo. Loyd v. Saint Joseph Mercy Oakland, 766 F.3d 580,
588 (6th Cir. 2014). Summary judgment is appropriate
when there is no genuine issue of material fact and the
moving party is entitled to judgment as a matter of law.
Fed. R. Civ. P. 56(a); Kalich v. AT & T Mobility, LLC,
679 F.3d 464, 469 (6th Cir. 2012).
III
A design patent is infringed “[i]f, in the eye of an ordi-
nary observer, giving such attention as a purchaser usually
gives, two designs are substantially the same, if the resem-
blance [can] deceive such an observer, inducing him to pur-
chase one supposing it to be the other.” Egyptian Goddess,
Inc. v. Swisa, Inc., 543 F.3d 665, 670 (Fed. Cir. 2008) (en
banc) (quoting Gorham Co. v. White, 81 U.S. 511, 528
(1871)). Where the claimed and accused designs are
“plainly dissimilar,” the patent owner does not meet its
burden of proving infringement. Egyptian Goddess,
543 F.3d at 678. “Differences . . . must be evaluated in the
context of the claimed design as a whole, and not in the
context of separate elements in isolation.” Ethicon Endo-
Surgery, Inc. v. Covidien, Inc., 796 F.3d 1312, 1335
(Fed. Cir. 2015).
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NORTH STAR TECHNOLOGY INTERNATIONAL LTD. v.
LATHAM POOL PRODUCTS, INC.
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As the district court correctly identified, the D’966 pa-
tent’s ornamental features are characterized by straight
edges and “geometric shapes”—producing an overall “an-
gular . . . appearance”—while the Corinthian 16 is charac-
terized by “rounded shapes” and a “curved” design. J.A. 15.
For example, the entry step in the D’966 patent is a pool-
width rectangle, while the Corinthian 16 has two separate
curved entry steps shaped like quarters of a circle. J.A.
15–16. Because no ordinary observer, defined by the dis-
trict court as a “homeowner considering purchasing a
swimming pool for their home,” J.A. 18, would accidentally
purchase one pool thinking it was the other, the designs
are plainly dissimilar.
Although the designs share structural similarities, de-
sign patents only protect the original, “nonfunctional as-
pects of an ornamental design as shown in the patent.”
Elmer v. ICC Fabricating, Inc., 67 F.3d 1571, 1577
(Fed. Cir. 1995) (citing KeyStone Retaining Wall Sys., Inc.
v. Westrock, Inc., 997 F.2d 1444, 1450 (Fed. Cir. 1993)).
North Star cannot monopolize common ornamental pool
features or functional pool features by registering a combi-
nation of those features as a design patent. See Lee v. Day-
ton-Hudson Corp., 838 F.2d 1186, 1188 (Fed. Cir. 1988)
(explaining that “[d]esign patents do not and cannot in-
clude claims to the structural or functional aspects of the
article” and are limited to the “ornamental design” of the
article); Egyptian Goddess, 543 F.3d at 674 (“[A] patented
design that consists ‘only of bringing together old elements
with slight modifications of form’ is not infringed by ‘an-
other who uses the same elements with his own variations
of form . . . if his design is distinguishable by the ordinary
observer from the patented design.’”) (quoting Zidell v. Dex-
ter, 262 F. 145 (9th Cir. 1920)). Both designs relate to rec-
tangular swimming pools with steps, benches, and tanning
ledges, but North Star’s patent only protects the ornamen-
tal aspect—here, the angular shape—of those ubiquitous
features.
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NORTH STAR TECHNOLOGY INTERNATIONAL LTD. v.
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We have considered North Star’s remaining arguments
regarding the district court’s allegedly erroneous decisions
to disregard or exclude certain evidence and find them un-
persuasive. The district court did not abuse its discretion
in declining to consider documents which were not relevant
or authenticated, or by striking lay testimony which lacked
foundation and amounted to expert testimony from a wit-
ness who was not qualified as an expert. We thus affirm
the district court’s grant of summary judgment on the issue
of non-infringement.
AFFIRMED
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