Kids2, LLC, F.k.a. Summer Infant (usa), Inc. v. Tomy International, Inc.

N OTE : This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
KIDS2, LLC, F.K.A. SUMMER INFANT (USA), INC.,
Plaintiff-Appellee
v.
TOMY INTERNATIONAL, INC.,
Defendant-Appellant
______________________
2023-1524
______________________
Appeal from the United States District Court for the
District of Rhode Island in No. 1:17-cv-00549-MSM-PAS,
Judge Mary S. McElroy.
______________________
______________________
Decided: January 14, 2025
R UBEN J OSE RODRIGUES, Foley & Lardner LLP, Boston,
MA, argued for plaintiff-appellee. Also represented by
SARAH E. R IEGER , Milwaukee, WI; J EFFREY T ECHENTIN, Ad-
ler Pollock & Sheehan, PC, Providence, RI.
J OSEPH KUO, Saul Ewing Arnstein & Lehr LLP, Chi-
cago, IL, argued for defendant-appellant. Also represented
by E LIZABETH A. THOMPSON.
______________________
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 2
Before C HEN, C UNNINGHAM , and STARK, Circuit Judges.
Opinion for the court filed by Circuit Judge STARK.
Opinion dissenting-in-part filed by Circuit Judge CHEN.
STARK, Circuit Judge.
TOMY International, Inc. (“TOMY”) appeals from a
grant of summary judgment of non-infringement. See
Summer Infant (USA), Inc. v. TOMY Int’l, Inc., 2023 WL
313959 (D.R.I. Jan. 19, 2023). Because there is a genuine
dispute of material fact as to whether the Summer Infant
(USA) Inc. (“Kids2”)1 accused product infringes, we reverse
and remand.
I
A
TOMY owns U.S. Patent No. 6,578,209 (“’209 pa-
tent”), entitled “Tubs for Bathing Infants and Toddlers.”
As its name suggests, the ’209 patent is directed to a mul-
tistage tub for bathing an infant and, as the child develops,
a toddler. The claimed tub “is configured with opposing
back rests and associated seating surfaces, for bathing an
infant reclining against one of the back rests, or a toddler
seated against the other back rest,” potentially eliminating
the need to replace the tub when an infant becomes a tod-
dler. ’209 patent at Abstract, 1:17-28.
Specifically, “[a] first of the opposing side walls ex-
tends at a first incline angle with respect to the rim” of the
tub to form a reclining backrest for an infant, and “a
1 During the pendency of this appeal, Summer Infant
was dissolved and, after a series of transactions, became
Kids2, LLC. We granted an unopposed motion to substi-
tute Kids2 as the appellee. For simplicity, we use Kids2
throughout this opinion.
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 3
second, opposite one of the opposing side walls extends at
a second incline angle with respect to the rim” of the tub to
form an upright backrest for a toddler. Id. at 1:36-40.
“[T]he first and second inclined side walls form[] back rests
for children seated in the tub in different orientations.” Id.
at 1:40-42. This configuration renders the tub “useful for
bathing at one time an infant reclined against the first
back rest, and then, at another time, bathing a child [(i.e.,
a toddler)] seated erect against the second back rest.” Id.
at 1:42-45. The tub also has a bottom surface that prefer-
ably “has two seating surface[s] disposed at differing incli-
nations and extending from respective back rests to distal
edges joined at a bottom surface apex spaced from either
end of the basin, each seating surface forming, together
with a respective one of the back rests, an inclined seat.”
Id. at 1:46-51.
Annotated Figure 13, reproduced below, depicts a
cross-sectional view of the seating surfaces in an embodi-
ment of the tub disclosed in the ’209 patent.
’209 patent at Fig. 13, 5:41-42. In this embodiment, “[a]t
the lower end of surface 62 [(shown in blue, on the infant
side)], a tub bottom surface 64 [(green)] extends upward
generally at an angle [] of about 45 degrees and forms a
seating surface associated with back rest 62, with apex 66
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 4
[(pink)] received behind the knees of the infant.” Id. at
5:47-51. “At the other end of the tub (the right end, as
shown), an opposing back rest 68 [(orange)] extends gener-
ally at the angle [] of about 77.5 degrees and serve[s] as a
back rest for a toddle[r] seated on generally horizontal seat-
ing surface 70 [(red)] . . . .” Id. at 5:51-54.
The ’209 patent has 31 claims. Independent claim 1
is illustrative:
A tub for bathing children, the tub com-
prising a molded plastic body having an upper
rim and defining a bathing basin sized for
bathing a young child and having a bottom
surface and opposing side walls forming oppo-
site ends of the basin,
a first of the opposing side walls extend-
ing at a first incline angle with respect to the
rim, and a second, opposite one of the oppos-
ing side walls extending at a second incline
angle with respect to the rim, the first and
second inclined side walls forming first and
second back rests for children seated in the
tub in different orientations;
the bottom surface having two seating sur-
faces disposed at differing inclinations and ex-
tending from respective back rests to distal
edges joined at a bottom surface apex spaced
from either end of the basin, each seating sur-
face forming, together with a respective one of
the back rests, an inclined seat;
wherein the body has a nominal thickness
and upper and lower surfaces having match-
ing shape across an overall extent of the tub
so as to enable the tub to nest within an iden-
tical tub with a nesting space differential of
less than about two inches (five centimeters).
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 5
Id. at 6:29-51 (emphasis added). The “bottom surface” lim-
itation, emphasized above, is central to the issues raised in
this appeal.
B
TOMY sells a baby bathtub, called the “Sure Com-
fort Deluxe,” which it asserts is an embodiment of the ’209
patent’s claims. In September 2017, Kids2 began selling a
competing baby bathtub, called the “Comfy Clean Deluxe.”
Less than a month later, TOMY sent Kids2 a cease-and-
desist letter, accusing Kids2’s Comfy Clean Deluxe of in-
fringing one or more claims of TOMY’s ’209 patent. Shortly
after receiving TOMY’s letter, Kids2 filed a declaratory
judgment action in the United States District Court for the
District of Rhode Island, seeking a determination that its
product did not infringe the ’209 patent. TOMY answered
Kids2’s complaint and filed counterclaims alleging that
Kids2’s product infringes the ’209 patent.
In May 2019, TOMY filed a motion for a claim con-
struction order. After briefing and oral argument, the mag-
istrate judge to whom the case was referred issued a report
and recommendation (“R&R”) on claim construction. Rele-
vant to this appeal, the magistrate judge construed a por-
tion of the “bottom surface” limitation – specifically, the
term “distal edges joined at a bottom surface apex” – as
“edges of the seating surfaces situated farthest away from
their respective back rests joined to each other at the area
of a high point of the bottom surface of the body between
the seating surfaces.” J.A. 79 (emphasis added). The mag-
istrate judge further concluded that the meaning of “seat-
ing surface(s)” “is clear and does not require further
construction,” adding that “‘seating surfaces’ plainly mean
the inclined (for the infant side) and generally horizontal
(for the toddler side) portions of the bottom surface that ex-
tend from the respective back rests to the central apex of
the bottom surface.” J.A. 71 (citing ’209 patent at 6:45-46).
Both parties objected to the R&R. After considering the
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 6
parties’ written objections and hearing oral argument, the
presiding district judge adopted the claim construction
R&R “in its entirety.” J.A. 11.
Subsequently, the parties filed cross-motions for
summary judgment of infringement and non-infringement,
as well as motions to exclude expert testimony. The mo-
tions were referred to the same magistrate judge who had
conducted claim construction. In another R&R, the magis-
trate judge, among other things, granted-in-part and de-
nied-in-part Kids2’s motion to preclude TOMY’s expert,
Mr. Mauro, from testifying, and recommended that the dis-
trict court: (i) grant Kids2’s motion for summary judgment
of non-infringement, (ii) deny TOMY’s motion for summary
judgment of infringement, and (iii) enter final judgment.
Over TOMY’s objections, the district court adopted the
R&R “in its entirety,” J.A. 8, and entered final judgment.2
TOMY timely appealed. We have jurisdiction under
28 U.S.C. § 1295(a)(1).
II
“We decide the proper claim construction and ad-
dress the intrinsic-evidence aspects of a claim-construction
analysis de novo, while we review for clear error any sub-
sidiary factual determinations based on extrinsic evidence
made by the district court.” Inline Plastics Corp. v. Lacerta
Grp., LLC, 97 F.4th 889, 901 (Fed. Cir. 2024). Claim terms
“are generally given their ordinary and customary mean-
ing,” which is the meaning understood by one of ordinary
skill in the art when read in the context of the claims, spec-
ification, and prosecution history. Phillips v. AWH Corp.,
415 F.3d 1303, 1313-14 (Fed. Cir. 2005) (en banc).
2 For simplicity, from this point forward we refer to the
decisions of both the district judge and the magistrate
judge as decisions of the “district court.”
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 7
“We review the district court’s grant or denial of
summary judgment under the law of the regional circuit,”
here the First Circuit. Halo Elecs., Inc. v. Pulse Elecs., Inc.,
831 F.3d 1369, 1376 (Fed. Cir. 2016). The First Circuit re-
views a grant of summary judgment de novo, evaluating
the “record in the light most flattering to the nonmovant”
and drawing “all reasonable inferences in that party’s fa-
vor.” Alston v. Town of Brookline, 997 F.3d 23, 35 (1st Cir.
2021). “Summary judgment is appropriate only when the
record, read as required, demonstrates that there is no gen-
uine issue as to any material fact and that the moving
party is entitled to judgment as a matter of law.” Id.
We also “apply regional circuit law when reviewing
a district court’s evidentiary rulings.” Omega Pats., LLC v.
CalAmp Corp., 13 F.4th 1361, 1368 (Fed. Cir. 2021). Under
First Circuit law, “we review a district court’s ruling on the
admissibility of expert testimony under Rule 702 for abuse
of discretion.” Rodríguez v. Hosp. San Cristobal, Inc., 91
F.4th 59, 71 (1st Cir. 2024).
III
On appeal, TOMY contends that the district court
adopted an incorrect claim construction for the “bottom
surface” claim limitation, and, as a result, also wrongly ex-
cluded testimony of TOMY’s infringement expert, granted
Kids2’s motion for summary judgment of noninfringement,
and denied TOMY’s motion for summary judgment of in-
fringement. We address each issue in turn.
A
TOMY first challenges the district court’s construc-
tion of the “bottom surface” claim term – “the bottom sur-
face having two seating surfaces disposed at differing
inclinations and extending from respective back rests to
distal edges joined at a bottom surface apex” – which ap-
pears in independent claims 1, 23, and 30 of the ’209 pa-
tent. TOMY raises three issues in relation to different
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 8
parts of the court’s construction of the “bottom surface” lim-
itation: (i) “distal edges joined at a bottom surface apex,”
(ii) “apex,” and (iii) “seating surfaces.” While we agree with
TOMY that the district court erred by limiting “distal edges
joined at a bottom surface apex” solely to direct connec-
tions, we are not persuaded by TOMY that the court com-
mitted any further claim construction error.
1
The parties’ dispute with respect to “distal edges
joined at a bottom surface apex” is, as the district court ex-
plained, “whether the patent claims that the distal edges
of each seating surface are connected directly, that is, edge-
to-edge, or whether the patent also claims indirect joinder,
that is, with edges meeting on either side of an intervening
structure.” J.A. 73. The district court resolved this dispute
in favor of Kids2, adopting the narrower view that the
claim requires the “edges of the seating surfaces situated
farthest away from their respective back rests [be] joined
to each other at the area of a high point of the bottom sur-
face of the body between the seating surfaces.” J.A. 79 (em-
phasis added). To reach this holding, the district court
distinguished dependent claim 18’s disclosure – “wherein
the seating surfaces are joined by a central bottom surface
portion that rises from the distal edge of one of the seating
surfaces to the distal edge of the other of the seating sur-
faces” – from independent claim 1’s disclosure – that the
“distal edges [are] joined at a bottom surface apex” – stat-
ing that it found “it impossible to avoid the force of [Kids2’s]
argument that ‘joined at,’ as the term appears unadorned
by further definition in Claims 1, 23 and 30, describes
clearly the joinder of the two distal edges to each other at
the apex; it does not encompass indirect joinder of the two
seating surfaces to a third intervening structure, as
claimed by dependent Claim 18.” J.A. 74-75 (emphasis
added). Hence, the district court agreed with Kids2 that
claims 1, 23, and 30 of the ’209 patent do “not encompass
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 9
indirect joinder of the two seating surfaces to a third inter-
vening structure.” J.A. 75. We disagree.
Claim 1 recites, in pertinent part, “two seating sur-
faces . . . extending from respective back rests to distal
edges joined at a bottom surface apex.” ’209 patent at 6:41-
44. There is no indication in this claim language that
“joined at” takes on anything other than its plain and ordi-
nary meaning, which would include any type of joining, di-
rect or indirect. See generally Deere & Co. v. Bush Hog,
LLC, 703 F.3d 1349, 1355 (Fed. Cir. 2012) (noting “joined,”
in context of upper and lower deck walls in rotary cutter,
does “not necessitate direct contact”); Genentech, Inc. v.
Chiron Corp., 112 F.3d 495, 501 (Fed. Cir. 1997) (explain-
ing, in context of DNA sequences, that “[t]o be joined or
connected does not necessitate a direct joining or connec-
tion.”). To read the limitation “joined at a bottom surface
apex” to require that the distal edges of the seating sur-
faces be “joined to each other at a bottom surface apex,” as
the district court did, imports language into the claim that
is not there. The term “at a bottom surface apex” indicates
where the distal edges of the two seating surfaces join but
does not limit how those distal edges must be joined.
Additional support for this conclusion is found in
claim 18, which depends from claim 1, and would be under-
stood by a skilled artisan as including indirect joinder.
Claim 18 recites:
The tub of claim 1 wherein the seating
surfaces are joined by a central bottom sur-
face portion that rises from the distal edge of
one of the seating surfaces to the distal edge
of the other of the seating surfaces.
’209 patent at 7:44-47.
Claim 18’s requirement that the seating surfaces “are
joined by a central bottom surface portion,” that rises from
the distal edges of the seating surfaces, can only be met by
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 10
embodiments in which those distal edges of the two seating
surfaces do not directly touch one another and are, instead,
joined only indirectly – by their respective connections to
the intervening central bottom surface portion. The ’290
patent’s specification expressly discloses this embodiment,
stating: “The seating surfaces may be joined by a central
bottom surface portion that rises from the distal edge of one
of the seating surfaces to the distal edge of the other of the
seating surfaces.” ’290 patent at 2:64-67.
Independent claim 1 must be broad enough to con-
tain the full scope of its dependent claims, including claim
18. See Littelfuse, Inc. v. Mersen USA EP Corp., 29 F.4th
1376, 1380 (Fed. Cir. 2022) (“By definition, an independent
claim is broader than a claim that depends from it, so if a
dependent claim reads on a particular embodiment of the
claimed invention, the corresponding independent claim
must cover that embodiment as well.”); Intellectual Ven-
tures I LLC v. T-Mobile USA, Inc., 902 F.3d 1372, 1378
(Fed. Cir. 2018) (stating that claim constructions rendering
“dependent claims meaningless” are generally “disfa-
vored”). Claim 18, then, provides substantial support for
TOMY’s position.3
We find still further support for TOMY’s proposed con-
struction in the specification and prosecution history.
3 We do not agree with the district court that “depend-
ent Claim 18 materially alters the words chosen for inde-
pendent Claims 1, 23 and 30, in that it omits the references
to ‘edges’ and recites that the ‘seating surfaces are joined
by a central bottom surface portion.’” J.A. 75 (quoting
claim 18). Claim 18 plainly requires that “a central bottom
surface portion” be situated between the distal edge of one
seating surface and the distal edge of the other seating sur-
face, indicating, as we have explained, that these “edges”
are joined indirectly.
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 11
Recall Figure 13, which we reproduced above. In the em-
bodiment depicted in Figure 13, the distal edge of the in-
fant seating surface 64 (annotated in green) and the distal
edge of the toddler seating surface 70 (annotated in red)
are not directly joined. Kids2, citing the prosecution his-
tory, argues that the unlabeled portion extending from 70
(annotated in yellow) is also part of the toddler seating sur-
face 70 (annotated in red).4 Whether or not the unlabeled
structure extending from 70 is considered part of the tod-
dler seating surface or an intervening structure, it is indis-
putable that elements 64 (green) and 70 (red) do not
directly join one another. Instead, they only indirectly join
either at the central bottom surface portion (yellow) or at
the apex 66 (pink). The district court’s construction, pre-
cluding indirect joinder, would read the embodiment of Fig-
ure 13 out of claim 1, a result contrary to our “strong
presumption against a claim construction that excludes a
disclosed embodiment.” In re Katz Interactive Call Pro-
cessing Pat. Litigation, 639 F.3d 1303, 1324 (Fed. Cir.
2011).
Our review of the intrinsic evidence, therefore,
4 During prosecution, the applicant described the em-
bodiment shown in Figure 13 as follows: “surface 64 forms
one seating surface [(i.e., the infant seating surface)], ex-
tending at inclination angle β1, and the other [(i.e., tod-
dler)] seating surface is formed by surface 70 and the
extension of surface 70 that meets surface 64 at apex 66.”
J.A. 695. In briefing to us, TOMY seeks to distance itself
from this interpretation, emphasizing instead that the un-
labeled portion (yellow) is an intervening structure indi-
rectly joining the distal edges of the two seating surfaces at
the apex (pink). Both views have support in the intrinsic
evidence, making it proper to consider both in carrying out
our obligation to construe the disputed claim term as a
matter of law.
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 12
persuades us that the correct construction of the claimed
“distal edges joined at a bottom surface apex” encompasses
both direct and indirect joinder. Because the claim con-
struction dispute is resolved on the intrinsic evidence, and
“[e]xtrinsic evidence may not be used to contradict claim
meaning that is unambiguous in light of the intrinsic evi-
dence,” Profectus Tech. LLC v. Huawei Techs. Co., 823 F.3d
1375, 1380 (Fed. Cir. 2016) (internal quotation marks omit-
ted), it is unnecessary for us to consider the extrinsic evi-
dence, Phillips, 415 F.3d at 1319 (explaining that courts
may exercise discretion in determining whether extrinsic
evidence is useful).
Thus, we construe “distal edges joined at a bottom
surface apex” as meaning the “areas of the seating surfaces
situated furthest away from their respective back rests are
connected directly or indirectly by an intervening structure
at a high point of the bottom surface of the body between
the seating surfaces,” as TOMY proposes. J.A. 71-72 (em-
phasis added). The district court must apply this construc-
tion on remand.
2
We reject TOMY’s contention that the district court
committed two other claim construction errors.
TOMY insists that the claimed “apex” need not
“span[] the width of the tub bottom.” While we agree with
TOMY on this point, so, too, did the district court. Its con-
struction of “apex” – “a surface that is higher than the other
portions of the tub’s bottom surface, located between the
seating surfaces” – does not require that the “apex” must
“span[] the width of the tub bottom.” J.A. 76. At most, the
district court suggested that in the embodiment depicted in
Figure 14 the apex is shown as “stretching across most of
the tub’s width,” id., but we do not read this description of
this embodiment as an explication of claim scope. Since
there is no error, there is nothing for us to correct.
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 13
TOMY also faults the district court for implicitly
construing “seating surfaces” based on their function in-
stead of limiting them to particular structures. It insists
“the district court effectively added requirements to the
construction of ‘seating surface’ including that it must sup-
port a child, that the child’s legs cannot straddle the seat-
ing surface, and that a ‘seating surface’ excluded near
vertical structures.” Appellant’s Br. 34. We do not see
where the district court imported any such limitations into
the construction of “seating surface.” During claim con-
struction, the district court concluded that the meaning of
the term “seating surface” is “clear and does not require
further construction.” J.A. 71 (“‘Seating surfaces’ plainly
mean the inclined (for the infant side) and generally hori-
zontal (for the toddler side) portions of the bottom surface
that extend from the respective back rests to the central
apex of the bottom surface. Together with their respective
back rests, each seating surface forms ‘an inclined seat.’”).
The court later explained, at summary judgment, that it
“did not reject the core concept that a seat functions as the
part on which one rests in [when] sitting,” and that this
“concept is embedded” in its plain meaning construction.
J.A. 23 (internal quotation marks omitted). TOMY pro-
vides no persuasive reason for us to add anything further
to the construction of “bottom surface” or “seating sur-
faces.”
B
The district court denied-in-part and granted-in-
part Kids2’s motion to exclude Mr. Mauro’s expert testi-
mony. Relevant here, the district court excluded Mr.
Mauro from offering infringement opinions built on his “il-
logical construct,” which “clash[ed] with the [district
court’s] claim construction,” as he would have opined that
the “two seating surfaces” could be indirectly “joined at a
bottom surface apex.” J.A. 33-35. Now that we have re-
versed the district court’s construction, and the court on
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 14
remand will have to apply our broader construction, the
premise for the exclusion ruling has been eliminated. See
generally Chamberlain Grp., Inc. v. Lear Corp., 516 F.3d
1331, 1339 (Fed. Cir. 2008) (explaining that where district
court “relies on an erroneous claim construction” in connec-
tion with other rulings, “this legal error may well consti-
tute an abuse of discretion” that must be reversed).
Mr. Mauro’s opinion – that the “seating surface for
the infant is shown as the substantially vertical portion for
the central protrusion extending upwards from the bottom
of the tub,” and that the seating surface for the toddler side
includes the “flat portion and upwardly curved portion,”
J.A. 1805 – as shown in the figures below, is not incon-
sistent with the correct claim construction, which permits
direct or indirect joinder of the seating surfaces.
J.A. 1836.
Our dissenting colleague, in critiquing Mr. Mauro for
espousing a theory of infringement that supposedly “evis-
cerates all meaning of ‘seating’ from the term ‘seating sur-
face,’” Dissent at 1-2, relies on a combination of TOMY’s
appellate briefing (not Mr. Mauro’s own words) and a read-
ing of excerpts from Kids2’s internal documents that is
something other than a reading in the light most favorable
to TOMY, see id. at 3-4. None of this, in our view, provides
a persuasive basis for excluding Mr. Mauro’s actual
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 15
opinion.5
Accordingly, we reverse the district court’s exclusion
of portions of Mr. Mauro’s testimony.
C
The district court’s grant of Kids2’s motion for sum-
mary judgment of non-infringement was, like its ruling on
the exclusion of Mr. Mauro’s testimony, predicated on its
rejection of TOMY’s construction of “distal edges joined at
a bottom surface.” Because we have now determined that
TOMY is correct that this term must be construed to in-
clude both direct and indirect connections, and we have de-
cided that Mr. Mauro’s testimony is not excludable based
on application of an erroneous claim construction, it follows
that we must reverse the judgment of non-infringement.
TOMY has pointed to other evidence, in addition to Mr.
Mauro’s opinion, that, taken in the light most favorable to
TOMY, might support a reasonable finding that Kids2’s ac-
cused tub infringes. For example, at least one of Kids2’s
own product documents, which describes the raised portion
of the bottom surface of the Comfy Clean Deluxe tub as a
“[c]ontoured seat,” could support a finding that the side
surface of the raised portion of the bottom surface consti-
tutes a “seating surface.” J.A. 1443; see also J.A. 1436. A
reasonable factfinder, taking the evidence in the light most
flattering to TOMY, might also find that the sliding-pre-
vention function of the raised hump of the bottom surface
additionally supports a finding that the side surface of the
raised hump is a “seating surface.” J.A. 1293 (Kids2 engi-
neer describing “how this little bump . . . prevents [a child]
from sliding down”).
5 There may be other grounds on which, on remand, the
district court might determine it must exclude some or all
of Mr. Mauro’s opinions.
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 16
In granting summary judgment of non-infringe-
ment, the district court also stated that Kids2’s accused tub
“has a relatively flat bottom surface comprised of two seat-
ing surfaces that flow into each other, around and past the
convex central hump that goes between the legs of the in-
fant or toddler and serves as a stop to prevent either the
infant or the toddler from slipping.” J.A. 47. Kids2 argues
that, in this portion of its order, the district court was ex-
plaining that it was granting summary judgment because
the accused product does not have two seating surfaces dis-
posed at differing inclinations. While it is not entirely clear
to us which claim limitation the district court was holding
the Comfy Clean Deluxe did not meet, if Kids2’s reading is
correct, we disagree with the district court. A reasonable
factfinder could find that the accused product has a “bot-
tom surface having two seating surfaces disposed at differ-
ing inclinations” because the basically horizontal
inclination of the toddler seating surface and the steeper
inclination of the infant seating surface could reasonably
be found to differ. J.A. 1497 (Mr. Mauro testifying that
“one of ordinary skill in the art just looks at” the “inclina-
tion” language of the claim as “simply” requiring “different
inclinations”).
Our conclusion relies on the view that the claimed “dif-
fering inclinations” include a zero-degree incline, i.e., that
one seating surface is horizontal. The Dissent faults that
conclusion as being both forfeited and wrong on the merits.
We disagree.
The Dissent contends that “TOMY never argues in its
briefing to us that the claim includes ‘zero incline,’” Dissent
at 6, which is not quite right. In its initial brief to us,
TOMY argued that in the accused tub “the seating surface
for the toddler has a relatively horizontal portion and a
modest incline portion, and the seating surface for the in-
fant has an incline relatively steeper than the toddler side.”
Appellant’s Br. 45; see also id. at 37 (“[T]he toddler seating
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 17
surface is the portion of the bottom surface that extends
from the left seatback to the apex, and the infant seating
surface is the portion of the bottom surface extending from
the right seatback to the apex. The slopes of these two seat-
ing surfaces are different. This is all that the claim re-
quires.”). Although TOMY did not use the phrase “zero
incline” in its brief, it is clear to us that TOMY was con-
tending that its claim includes seating surfaces of various
inclinations, including a zero-degree incline.6 The limita-
tion requires “seating surfaces disposed at differing incli-
nations,” and TOMY’s position before us has consistently
included potentially all inclinations, including a zero-de-
gree incline, as long as the two seating surfaces have dif-
ferent inclinations.
On the merits, we agree with TOMY that different in-
clinations, whatever they may be (including a zero-degree
incline), “is all that the claim requires.” Appellant Br. 37.
We see nothing in the claim language or specification, and
the Dissent points to nothing, to support a conclusion that
a person of ordinary skill in the art would exclude a zero
angle from her understanding of “inclination.”7 To the
6 As the Dissent acknowledges, TOMY made this point
even more clearly during oral argument. See Dissent at 6-
7 (quoting oral argument).
7 The parties did not present a claim construction dis-
pute over the meaning of “inclination.” Even if we were to
say we have such a dispute before us now, we see no reason
to conclude that a person of ordinary skill would ignore the
intrinsic evidence and understand this term based solely
on the definition from an online general use dictionary re-
lied upon by the Dissent. See Dissent at 6. Moreover, even
under the Dissent’s definition, it does not necessarily follow
that the amount of “deviation from the true vertical or hor-
izontal” cannot be zero degrees.
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 18
contrary, one claim, claim 17, actually requires “the seat-
ing surface associated with the first inclined wall is dis-
posed generally horizontally,” meaning it requires a
seating surface with an incline at or near zero. Other
claims, specifically claims 12-16, require that an “inclined
wall” extend either at a specific angle (“about 41 degrees,”
“about 45 degrees,” “about 77 degrees”) or at a specific
range of angles (“between about 35 and 45 degrees,” “be-
tween about 70 and 85 degrees”), further indicating that
claims not specifying any particular inclination do not ex-
clude any inclination.
The Dissent’s contention that the prosecution history
provides “quite clear” support for its conclusion is, in our
view, likewise unavailing. Dissent at 8. It wrongly sug-
gests that TOMY told the U.S. Patent and Trademark Of-
fice that “the toddler seating surface must include both
horizontal surface 70 [red] and the inclined extension of
surface 70 [yellow]” to meet the “disposed at differing incli-
nations” limitation. Dissent at 8 (emphasis added). It is
true that during prosecution the applicant responded to an
examiner’s antecedent basis objection of two seating sur-
faces “disposed at differing inclinations” (in connection
with unasserted claim 22) by stating that the toddler seat-
ing surface of the Figure 13 embodiment “is formed by sur-
face 70 and the extension of surface 70 that meets surface
64 at apex 66,” J.A. 695, but the applicant never said that
the differing inclinations are not also satisfied even with-
out considering the yellow extension. That is, contrary to
the Dissent, the applicant did not tell the Patent Office that
the “generally horizontal seating surface 70 on its own” was
“insufficient.” Dissent at 7-8 (internal quotation marks
omitted).
Accordingly, we reverse the district court’s grant of
summary judgment of non-infringement and remand for
further proceedings.
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KIDS 2, LLC v. TOMY INTERNATIONAL , INC. 19
D
Finally, we affirm the district court’s denial of TOMY’s
motion for summary judgment of infringement. While we
have set out above a portion of the evidence from which a
reasonable factfinder, taking the evidence in the light most
flattering to TOMY, could find that Kids2’s Comfy Clean
Deluxe tub infringes the ’209 patent, nothing we have said
should be taken to mean that such a factfinder would be
compelled to make such a finding. Viewing the evidence in
the light most favorable to Kids2, as the party opposing
TOMY’s motion, a reasonable factfinder is clearly free to
reject Mr. Mauro’s opinion and the other evidence we have
highlighted and, consequently, find no infringement.
Thus, TOMY is not entitled to summary judgment.
IV
We have considered the parties’ remaining arguments
and find them unpersuasive. For the foregoing reasons, we
(i) reverse the district court’s (a) “bottom surface” claim
construction, (b) its exclusion of portions of Mr. Mauro’s
testimony, and (c) its grant of summary judgment of non-
infringement, and (ii) affirm the court’s denial of summary
judgment of infringement. We remand for further proceed-
ings consistent with this opinion.
REVERSED-IN-PART, AFFIRMED-IN-PART,
AND REMANDED
COSTS
Costs awarded to TOMY.
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N OTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
KIDS2, LLC, F.K.A. SUMMER INFANT (USA), INC.,
Plaintiff-Appellee
v.
TOMY INTERNATIONAL, INC.,
Defendant-Appellant
______________________
2023-1524
______________________
Appeal from the United States District Court for the
District of Rhode Island in No. 1:17-cv-00549-MSM-PAS,
Judge Mary S. McElroy.
______________________
CHEN, Circuit Judge dissenting-in-part.
Both on appeal and before the district court, TOMY has
offered “evolving theories of infringement.” J.A. 27. As the
magistrate judge aptly observed, “TOMY has struggled to
explain how [the Accused Tub] also meets the ’209 Patent’s
ubiquitous limitation of ‘two seating surfaces disposed at
differing inclinations and extending from respective back
rests to distal edges joined at a bottom surface apex.’” Id.
TOMY advances two infringement theories, but both are
fatally flawed. The first theory, which contends a near-ver-
tical wall in the Accused Tub is a seating surface, eviscer-
ates all meaning of “seating” from the term “seating
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KIDS2, LLC v. TOMY INTERNATIONAL , INC. 2
surface.” The second theory, which claims a flat horizontal
surface is the seating surface, similarly eviscerates the “dif-
fering inclinations” limitation from the claim.
TOMY’s infringement theories fail regardless of how
the disputed claim limitation is construed. If we affirm the
district court’s construction, then TOMY must rely on its
first infringement theory, which requires an unreasonable
understanding of what a “seating surface” may encompass.
If we adopt TOMY’s proposed construction, TOMY’s second
infringement theory failed to argue or explain how the Ac-
cused Tub’s horizontal seating surface has an “inclination.”
And, regardless, it doesn’t. In my view, the district court
correctly handled the issues presented to it based on the
arguments made. I join the court’s opinion at parts III.A.2
and III.D, but I would affirm the district court’s claim con-
struction, exclusion of TOMY’s expert opinions on infringe-
ment, and grant of summary judgment of noninfringement.
Accordingly, I respectfully dissent.
I
Under its first infringement theory, TOMY argues the
near-vertical sidewall of the Accused Tub’s central hump is
part of the toddler seating surface. I am not persuaded that
this is an issue that merits a trial. Under its plain and
ordinary meaning, a “seating surface” is something that
one sits on, not something that one sits against.
Mr. Mauro’s infringement opinions require an illogical
and unreasonable understanding of the plain and ordinary
meaning of “seating surface.” When a toddler is sitting in
the Accused Tub, the central hump (the vertical sidewall of
which Mr. Mauro contends is a seating surface) sticks up
and is located between the toddler’s legs. It is thus appro-
priate to exclude Mr. Mauro’s infringement opinions be-
cause he reads “seating” out of the term “seating surface.”
Mr. Mauro is not arguing that a toddler actually sits on the
hump sidewall because they can squirm such that their
bottom slides up against the sidewall. Mr. Mauro instead
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KIDS2, LLC v. TOMY INTERNATIONAL , INC. 3
argues, without meaningful explanation, that the hump
sidewall is part of the toddler seating surface. J.A. 1416;
see also Appellant’s Br. 39 (arguing the hump sidewall “is
clearly a seat because the child necessarily rests against
it”).1 However, resting against something is not the same
as sitting on it—a footrest would necessarily support part
of a toddler’s weight but would not be considered a seating
surface. 2 Likewise, no one would suggest a backrest of a
chair or the Accused Tub is a seating surface just because
someone can rest part of their weight against it when
1 Mr. Mauro identified only the sidewall of the cen-
tral hump as the infant seating surface (see J.A. 1836–37),
but, at a minimum, part of the flat portion on the infant
side should also be the seating surface because an infant
would, as TOMY argues, necessarily rest their weight
against part of the flat portion. It is questionable whether
this sidewall on the infant side is part of the seating surface
for the same reasons that the sidewall on the toddler side
should not be part of the seating surface.
2 During oral argument, TOMY’s counsel rather non-
sensically argued a footrest would be “a seat for your feet”
and therefore a seating surface. Oral Arg. at 43:06–23,
available at https://oralarguments.cafc.uscourts.gov/de-
fault.aspx?fl=23-1524_06072024.mp3.
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KIDS2, LLC v. TOMY INTERNATIONAL , INC. 4
sitting on the true seating surface, which in this case is the
flat surface in Accused Tub where the toddler actually sits.
Appellee’s Br. 3.
Based on Kids2’s internal documents, the Accused
Tub’s central hump is not a seating surface but rather a
restraint for how far forward a sitting toddler can move
within the tub. J.A. 1435 (“built-in contoured support
keeps baby from sliding in the tub”); J.A. 1441 (“Horn re-
shaped to prevent slipping”). That kind of contoured sup-
port is no different in principle than, say, a contoured,
concave-shaped backrest that would help maintain and
confine the location of where the toddler sits. Such features
help further define the sitting location, but they don’t serve
as the sitting location itself. Because a restraint is some-
thing one, at most, rests against, not something that one
sits on, I do not agree that “the sliding-prevention function
of the raised hump of the bottom surface additionally sup-
ports a finding that the side surface of the raised hump is
a ‘seating surface.’” Maj. at 15. Contrary to the majority’s
assertions, reading Kids2’s internal documents “in the
light most favorable to TOMY” does not require expanding
“seating surface” to include mechanisms that restrain
movement, as doing so would eviscerate the term’s plain
and ordinary meaning. Id. at 14.
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KIDS2, LLC v. TOMY INTERNATIONAL , INC. 5
II
Under its second infringement theory, TOMY argues
the near-vertical sidewall of the central hump is an “inter-
vening structure,” leaving only a “horizontal seating sur-
face” as the toddler seating surface. Appellant’s Reply
Br. 23; see also Appellant’s Br. 20–21, 25–27. This theory
benefits from not having to rely on a wall as counting as
part of the “seating surface,” but the district court correctly
spotted defects here as well.
As a threshold matter, I believe the district court cor-
rectly construed the claim to exclude indirect joinder of the
claimed two seating surfaces. Under its plain and ordinary
meaning, “distal edges [of the two seating surfaces] joined
at a bottom surface apex” means the seating surfaces’s dis-
tal edges are directly joined to each other through the apex.
In other words, the distal edges cannot be indirectly joined
at the apex through an intervening structure.
Dependent claim 18 does not clearly contemplate indi-
rect joinder by a “central bottom surface portion” (i.e., in-
tervening structure). The sole description of this term in
the specification refers to an embodiment of the apex, as it
necessarily encompasses the apex, and does not, as the ma-
jority asserts, refer to an intervening structure that indi-
rectly joins the two seating surfaces. Maj. at 10 (quoting
’209 patent at col. 2, ll. 64–67 (“The seating surfaces may
be joined by a central bottom surface portion that rises
from the distal edge of one of the seating surfaces to the
distal edge of the other of the seating surfaces.”)). This un-
derstanding of “central bottom surface portion” is fully con-
sistent with the district court’s construction of “apex,”
which no party disputes: “an area of a high point of the bot-
tom surface between the seating surfaces.” J.A. 76–77, 79
(emphasis added).
Although the majority asserts the apex itself is an in-
tervening structure that indirectly joins the distal edges,
Maj. at 11–12, TOMY never argued the case that way.
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KIDS2, LLC v. TOMY INTERNATIONAL , INC. 6
Rather, TOMY argues the unlabeled portion (yellow) is the
“central bottom surface portion” that indirectly joins the
seating surfaces’s distal edges at the apex 66 (pink). Ap-
pellant’s Br. 20–21 (see annotated Figure 13 below), 25–26;
Appellant’s Reply Br. 10–11. Thus, TOMY clearly consid-
ers the apex as distinct from any alleged intervening struc-
ture. The majority, in my view, engages in its own
independent inquiry untethered from TOMY’s arguments.
Regardless, even if the claim is construed to include in-
direct joinder, TOMY’s infringement theory still fails be-
cause the Accused Tub would not meet the “two seating
surfaces disposed at differing inclinations” limitation.
TOMY admits that the Accused Tub’s toddler seat under
this theory is “a horizontal seating surface.” Appellant’s
Reply Br. 23. The majority asserts that the claim language
does not exclude a horizontal angle of zero degrees to the
bottom surface from the required “inclinations,” Maj. at
17–18, but under its plain and ordinary meaning, an “incli-
nation” is “a deviation from the true vertical or horizontal”
(i.e., “slant”). Inclination, Merriam-Webster, available at
https://www.merriam-webster.com/dictionary/inclination.
In other words, to say an inclination can be no inclination
means this limitation is really no claim limitation at all.
More importantly, TOMY never argues in its briefing
to us that the claim includes “zero incline.” When asked
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KIDS2, LLC v. TOMY INTERNATIONAL , INC. 7
about this at oral argument, TOMY argues what the ma-
jority argues now. Oral Arg. at 4:37–51 (arguing that the
’209 patent contemplates “completely flat” seating surfaces
because “an incline of zero is still something that is meas-
urable”), 7:54–8:37 (arguing that “differing inclinations” is
met because one seating surface is “horizontal” and the
other seating surface is “pitched somewhat”), 9:18–44 (ar-
guing that, “in the context of this patent,” all surfaces, even
a “flat” surface with “zero” incline, is “inclined”). But it is
too late for TOMY to correct the defect from its briefs. See,
e.g., Hannon v. Dep’t of Just., 234 F.3d 674, 680 (Fed. Cir.
2000) (arguments made after the opening appeal brief that
are not in the opening brief come too late to be considered).
Although the majority contends TOMY did argue that the
claims include a zero-degree incline, Maj. at 16–17 (quoting
Appellant’s Br. 37, 45), those quotes were made in the con-
text of the first infringement theory—in arguing that the
near-vertical sidewall of the Accused Tub’s central hump is
part of a seating surface—and were not asserted for alleg-
ing that a flat surface with no incline meets the “inclina-
tions” limitation. That TOMY argued the claim includes a
90-degree incline does not mean TOMY affirmatively ar-
gued the claim also includes a zero-degree incline.
In addition to the plain and ordinary meaning, the
prosecution history reinforces my view that the ’209 patent
claims require the two seating surfaces to be inclined at
different angles. During prosecution, when the patent ex-
aminer “objected to the specification as failing to provide
antecedent basis” for the “disposed at differing inclina-
tions” limitation, TOMY pointed to Figure 13 and then ex-
plained the limitation was met because “surface 64 forms
one seating surface, extending at inclination angle β1, and
the other seating surface is formed by surface 70 and the
extension of surface 70 that meets surface 64 at apex 66.”
J.A. 695 (emphasis added). In other words, “generally hor-
izontal seating surface 70” on its own was, in TOMY’s view,
insufficient to meet the limitation because, otherwise,
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KIDS2, LLC v. TOMY INTERNATIONAL , INC. 8
TOMY need not have included the inclined extension of
surface 70 as part of the toddler seating surface to over-
come the examiner’s objection. ’209 patent at col. 5, l. 54.
The majority contends that TOMY did not tell the U.S. Pa-
tent and Trademark Office the “generally horizontal” por-
tion alone was insufficient, Maj. at 18, but in my view, it is
quite clear that TOMY was explaining to the Patent Office
that the toddler seating surface must include both horizon-
tal surface 70 and the inclined extension of surface 70 to be
“disposed at differing inclinations.” The specification does
not present a contrary, or any, explanation of the extension
of surface 70 depicted in yellow in annotated Figure 13.3
See ’209 patent col. 5 ll. 40–55. TOMY should not be al-
lowed to tell the courts one thing about what can be a seat-
ing surface with an inclination when it told the Patent
Office something very different during prosecution.
For TOMY to prevail under its second infringement
theory, the inclined limitation would have to be met by non-
inclined surfaces. But that conflicts with the claim lan-
guage and is neither supported by the record nor how this
case was litigated. It was thus appropriate and correct for
the district court to conclude that the claim “calls for two
seating surfaces that rise at different angles” and such a
limitation cannot be met by a “flat bottom surface,” J.A. 8,
or, in TOMY’s own words, “a horizontal seating surface,”
Appellant’s Reply Br. 23.
3 The prosecution history is clear that the extension
of surface 70 is a portion of the seating surface itself, rather
than a separate intervening structure. J.A. 695. This un-
dermines TOMY’s proposed construction, which argues the
claim allows for indirect joinder of the seating surfaces’s
distal edges because the extension of surface 70 is suppos-
edly an “intervening structure.” Appellant’s Br. 20–21.
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KIDS2, LLC v. TOMY INTERNATIONAL , INC. 9
CONCLUSION
For the foregoing reasons, I respectfully dissent. Alt-
hough a party should have its right to trial when there are
genuine issues of material fact, I see none here. I would
affirm the district court on all issues.
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