Case: 20-1047 Document: 45 Page: 1 Filed: 10/02/2020
NOTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
HOIST FITNESS SYSTEMS, INC.,
Plaintiff-Appellant
v.
TUFFSTUFF FITNESS INTERNATIONAL, INC.,
Defendant-Appellee
______________________
2020-1047
______________________
Appeal from the United States District Court for the
Central District of California in No. 5:17-cv-01388-AB-KK,
Judge Andre Birotte, Jr.
______________________
Decided: October 2, 2020
______________________
LARA SUE GARNER, Gordon & Rees, San Diego, CA, ar-
gued for plaintiff-appellant. Also represented by SEAN
DONOVAN FLAHERTY, MATTHEW G. KLEINER, SUSAN B.
MEYER.
RUDOLPH A. TELSCHER, JR., Husch Blackwell LLP, St.
Louis, MO, argued for defendant-appellee. Also repre-
sented by KARA RENEE FUSSNER, DAISY MANNING.
______________________
Case: 20-1047 Document: 45 Page: 2 Filed: 10/02/2020
2 HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS
Before LOURIE, SCHALL, and DYK, Circuit Judges.
SCHALL, Circuit Judge.
Plaintiff-Appellant Hoist Fitness Systems, Inc.
(“Hoist”) appeals from the September 10, 2019 final judg-
ment of noninfringement entered in the United States Dis-
trict Court for the Central District of California in Hoist’s
patent infringement suit against Defendant-Appellee Tuff-
Stuff Fitness International, Inc. (“TuffStuff”). Hoist Fit-
ness Sys., Inc., v. TuffStuff Fitness Int’l, Inc., Final
Judgment, No. 5:17-cv-01388-AB-KK, Dkt. No. 300 (C.D.
Cal. Sept. 10, 2019), J.A. 24–25 (“Final Judgment”). Hoist
sued TuffStuff for infringement of the following six patents:
U.S. Patent No. 7,594,880 (“the 880 patent”); U.S. Patent
No. 7,563,209 (“the ’209 patent”); U.S. Patent No. 7,549,949
(“the ’949 patent”); U.S. Patent No. 7,654,938 (“the ’938 pa-
tent”); U.S. Patent No. 7,976,440 (“the ’440 patent”); and
U.S. Patent No. 7,993,251 (“the ’251 patent”). Judgment
was entered pursuant to the parties’ stipulation following
the district court’s final pronouncement on claim construc-
tion at a pretrial status conference held on September 9,
2019. Joint Stipulation for Entry of Judgment, No. 5:17-
cv-01388-AB-KK, Dkt. No. 298 (C.D. Cal. Sept. 10, 2019),
J.A. 26–29 (“Joint Stipulation”). Because we discern no er-
ror in the district court’s claim construction, we affirm.
BACKGROUND
I.
Hoist’s patents are directed to “exercise machine[s]
with a pivoting user support.” ’938 patent col. 1 ll. 15–17.
The patents state that the “user support frame moves in
conjunction with the exercise arm” so the user experiences
a “more natural feeling exercise movement that more
closely replicates the movement found in the corresponding
free weight exercise.” Id. at col. 4 ll. 11–16. The patents
describe and illustrate two general kinds of mechanisms
that may be used to pivotally mount a user support frame
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HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS 3
onto an exercise machine’s main frame to achieve this ob-
jective: (1) a single pivot; 1 or (2) a “four-bar linkage,” which
is a multiple part pivot assembly having multiple pivots. 2
Such four-bar linkage mechanisms have a “theoretical”
pivot axis that is a point reflecting a composite center of
rotation for the user support frame. See ’938 patent col. 6
ll. 6–17; ’209 patent col. 6 ll. 42–50. As explained in the
’938 patent:
The multiple part pivot assembly defines a theoret-
ical pivot axis of the user support pivotal motion.
As illustrated in FIGS. 3 and 4, the theoretical
pivot axis 84 is located below the user support, and
a theoretical gravitational center line 74 of the piv-
otal motion extending through pivot axis 84 also
extends through the user support frame 15. The
location of the theoretical pivot axis 84 can be de-
termined from the start and end positions of the
two pivot links 60 and 62, and is the point of inter-
section of the centerline A of the pivotal movement
of the forward link 62 and the centerline B of the
pivotal movement of the rear link 60, as indicated
in FIGS. 3 and 4.
’938 patent col. 6 ll. 6–17. For purposes of addressing the
claim construction issues presented in this appeal, we con-
sider claim 22 of the ’880 patent and claim 1 of the ’938
patent representative of the relevant claims of the six Hoist
patents at issue. Claim 22 of the ’880 patent recites:
1 See, e.g., ’880 patent col. 10 l. 51–col. 22 l. 63 & Figs.
5–32; ’949 patent col. 3 l. 13–col. 7 l. 11 & Figs. 1–6.
2 See, e.g., ’938 patent col. 5 l. 63–col. 6 l. 17 & Figs.
1–4; ’949 patent col. 7 l. 12–col. 8 l. 26 & Figs. 7A–8.
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4 HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS
22. An exercise machine, comprising:
a main frame;
a user support frame pivotally mounted relative to
the main frame for rotation about a user support
pivot axis, the user support pivot axis defining a
vertical, gravitational center line, the user support
frame comprising one moving part of the machine;
the user support frame having at least a primary
support and a secondary support for supporting
spaced positions on a user’s body throughout an ex-
ercise movement, the primary support comprising
a seat pad and the secondary support comprises a
leg support which travels in the same direction as
the primary support throughout an exercise move-
ment;
a user engagement device movably mounted on one
of the frames for engagement by the user in per-
forming exercises, the user engagement device
comprising a second moving part of the machine;
a connecting link linking movement of the user en-
gagement device to movement of the user support
frame, the connecting link comprising a third mov-
ing part of the machine; and
a load for resisting movement of at least one of the
moving parts of the machine; whereby movement
of the user engagement device in an exercise move-
ment simultaneously moves the user support frame
between a start position and an end position, the
user support pivot axis being positioned such that
portions of the combined weight of the user and
user support frame are distributed on each side of
the gravitational center line of the user support
pivot axis in both the start and end position and
only a portion of the combined weight passes
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HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS 5
through the gravitational center line during the ex-
ercise movement.
’880 patent col. 28 l. 44–col. 29 l. 14. Claim 1 of the ’938
patent recites:
1. An exercise machine, comprising:
a stationary main frame having an upper end, a
lower end, a first end, and a second end;
a user support frame which is adapted to support a
user in an exercise ready position on the main
frame;
a multiple part pivot assembly pivotally mounting
the user support frame relative to the main frame
and having multiple pivots which together control
pivotal movement of the user support frame in an
arcuate exercise movement path about a central
pivot axis;
the user support frame having at least a primary
support and a secondary support which support
spaced positions on a user’s body throughout an ex-
ercise movement, the secondary support being se-
cured at a fixed and unchanging angular
orientation relative to the primary support at least
throughout an exercise movement, the primary
support supporting the majority of a user’s weight
in the start position of the support frame;
a user engagement device movably mounted rela-
tive to the frames for engagement by the user in
performing exercises;
a connecting linkage which translates movement of
the user engagement device during an exercise to
movement of the user support frame;
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6 HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS
a load for resisting movement of at least one of the
user support, user engagement device, and con-
necting linkage; and
the central pivot axis of the pivotal movement of
the user support frame being positioned such that
a gravitational center line which extends vertically
through the central pivot axis also extends through
the user support frame during at least part of the
arcuate exercise movement path of the user sup-
port frame and only a portion of the combined
weight of the user and user support frame passes
through the gravitational center line during an ex-
ercise.
’938 patent col. 9 l. 56–col. 10 l. 25.
II.
On April 3, 2017, Hoist sued TuffStuff in the Southern
District of California, alleging infringement of claim 22 of
the ’880 patent; claims 6 and 21 of the ’209 patent; claims
2, 8, and 23 of the ’949 patent; claims 1, 12, and 13 of the
’938 patent; claims 5, 12, 13, and 20 of the ’440 patent; and
claims 54 and 71 of the ’251 patent. Compl., No. 3:17-cv-
00670, Dkt. No. 1 (S.D. Cal. Apr. 3, 2017) at 6–11, J.A. 330–
35. The case was subsequently transferred to the Central
District of California.
The exercise devices which Hoist accused of infringe-
ment are part of TuffStuff’s “Bio-Arc” line of products. The
TuffStuff devices have a user support that is mounted on a
pivot that is, in turn, mounted on a sliding carriage that
translates back and forth along a linear shaft during the
exercise movement. Def.’s Not. of Mot. and Mot. for Summ.
J, Ex. 17, Decl. of D. Penado, No. 5:17-cv-01388-AB-KK,
Dkt. No. 144-17 (C. D. Cal. Dec. 26, 2018) at 2–16, J.A.
3773–87. The accused TuffStuff devices have structure
that both pivots and slides, resulting in a “combined ellip-
tical movement.” Pl.’s Notice of Mot. and Mot. for Prelim.
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HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS 7
Inj. to Enjoin Infringement of the ’880 Patent, No. 5:17-cv-
01388-AB-KK, Dkt. No. 33 (C.D. Cal. Sept. 5, 2017) at 16–
17, J.A. 481–82.
III.
In the course of the proceedings below, the district
court construed a number of claim terms. The joint stipu-
lation for entry of judgment of noninfringement, however,
was based upon the court’s construction of just three terms:
“pivotally mounted relative to the main frame,” “pivotally
mounting the user support frame relative to the main
frame,” and “pivotally mounted on the main frame.” Joint
Stipulation at 2, J.A. 27. Accordingly, it is to these related
terms that we direct our attention. The term “pivotally
mounted relative to the main frame” appears in independ-
ent claim 22 of the ’880 patent in the limitation “a user sup-
port frame pivotally mounted relative to the main frame for
rotation about a user support pivot axis, the user support
pivot axis defining a vertical, gravitational center line.”
’880 patent col. 28 ll. 47–50. 3 The term “pivotally mounting
the user support frame relative to the main frame” appears
in independent claim 1 and, through their dependency on
claim 1, claims 12 and 13 of the ’938 patent, in the limita-
tion “a multiple part pivot assembly pivotally mounting the
user support frame relative to the main frame and having
multiple pivots which together control pivotal movement of
the user support frame in an arcuate exercise movement
path about a central pivot axis.” ’938 patent col. 9 ll. 61–
3 The term “pivotally mounted relative to the main
frame” also appears in independent claims 6 and 21 of the
’209 patent, independent claims 2, 8, and 23 of the ’949 pa-
tent, and independent claims 5 and 20 of the ’440 patent.
See ’209 patent col. 15 ll. 31, 54–57 & col. 16 l. 66; ’949 pa-
tent col. 12 ll. 14 & 63, col. 13 ll. 29 & 42–43, col. 15 l. 19;
’440 patent col. 11 ll. 47–48 & col. 14 ll. 51–52.
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8 HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS
65 & col. 11 ll. 7–12. 4 The term “pivotally mounted on the
main frame” appears in independent claims 54 and 71 of
the ’251 patent in the limitation “a user support frame piv-
otally mounted on the main frame which supports a user
in an exercise position.” ’251 patent col. 21 ll. 28–29, col.
22 ll. 62–63. Where appropriate, we refer to these as the
“pivotally mounted/mounting terms.”
In a claim construction order issued on October 24,
2018, the district court determined that no construction
was necessary for the pivotally mounted/mounting terms.
Claim Construction Order, No. 5:17-cv-01388-AB-KK, Dkt.
No. 111 (C.D. Cal. Oct. 24, 2018) at 15, J.A. 44. The court
observed, though, that construing “pivot” and “rotation” to
include “more than generally ‘concentric’ movement would
effectively destroy the meaning of those terms as they were
understood by the patent applicant.” Id. at 14, J.A. 43.
On August 27, 2019, two weeks before the date sched-
uled for trial, the district court addressed claim construc-
tion again, when it ruled on the parties’ respective motions
in limine. See Order Regarding Parties’ Mots. in Lim. and
Construing Additional Disputed Claim Terms, No. 5:17-cv-
01388–AB-KK, Dkt. No. 279 (C.D. Cal. Aug. 27, 2019) (“Au-
gust 27, 2019 Order”), J.A. 95. The court (1) construed
“pivotally mount[ed]/[ing] relative to the main frame” as
“mount[ed]/[ing] such that the overall movement relative
to the main frame is generally concentric; provided, how-
ever, that movement need not be perfectly circular;”
(2) construed “pivotally mounted on the main frame” as
“mounted, either directly or indirectly, to the main frame
such that the overall movement relative to the main frame
is generally concentric; provided, however, that movement
4 The term “pivotally mounting the user support
frame relative to the main frame” also appears in inde-
pendent claims 12 and 13 of the ’440 patent. ’440 patent
col. 13, ll. 13–14 & 54–55.
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HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS 9
need not be perfectly circular;” and (3) construed “arcuate
exercise movement path about a central pivot” as an “over-
all movement path that is generally concentric about a sin-
gle central pivot point; provided, however, that movement
need not be perfectly circular around the central pivot
point.” Id. at 7, J.A. 101. In its order, the court stated that
it would permit Hoist’s expert, Steven M. Lenz, to serve a
supplemental report responding to its claim construction.
Id. at 8, J.A. 102. Hoist served its expert’s supplemental
report on September 6, 2019. J.A. 9340.
On September 9, 2019, the day before trial was sched-
uled to begin, the court held a status conference. At the
conference, the court provided further guidance regarding
construction of the pivotally mounted/mounting terms, in
light of its view that “concentric is more synonymous with
circular” as opposed to “hav[ing] a common center or to be
aligned.” J.A 9439–40. The court stated:
All right. I have considered the argument of both
counsel in the case. Look, the Court—I guess I take
the view that the supplemental expert report has
just interpreted the term “concentric” too broadly.
The plaintiffs—I guess, if I understand Lenz’s re-
port correctly, concentric means to have a common
center or to be aligned, just looking at the report
again. Defense believes concentric is more synony-
mous with circular. Quite frankly, the Court
agrees with the defense on this one based on the
Court’s orders and the patents themselves.
When you look at the claim language, it requires
pivotal movement, and the claim term we have
been construing here is “pivotally mounted.” I
think the ordinary meaning of a pivot is a fixed
point with movement around that point. And so,
by construing the term to include generally concen-
tric movement, we were trying to clarify that the
patents that described this four-bar linkage
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10 HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS
assembly embodiment would not require a per-
fectly circular motion. But I think the plaintiff’s
interpretation as concentric is something much
broader than circular goes beyond these examples
and I think beyond the meaning of pivot.
Id.
The effect of this pronouncement was to leave the par-
ties with a claim construction that combined what the court
had said in its claim construction order of October 24, 2018,
and at the September 9 status conference. Accordingly, the
pivotally mounted/mounting terms were effectively con-
strued to mean:
mount[ed]/[ing] such that the overall movement
relative to the main frame is generally concentric
[“concentric” is “more synonymous with circular”
rather than meaning “having a common center”];
provided, however, that movement need not be per-
fectly circular. 5
In view of its claim construction, the district court
struck the supplemental report of Hoist’s expert. 6
5 Similarly, the term “pivotally mounted on the main
frame” was effectively construed to mean:
mounted, either directly or indirectly, to the main
frame such that the overall movement relative to
the main frame is generally concentric [“concen-
tric” is “more synonymous with circular” rather
than meaning “having a common center”]; pro-
vided, however, that movement need not be per-
fectly circular.
6 In his supplemental report, Hoist’s expert Mr. Lenz
stated that a person of ordinary skill in the art “would un-
derstand “concentric” as “having a common center,”
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HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS 11
On September 10, based upon the claim construction
advanced by the district court at the September 9 status
conference, the parties stipulated to entry of judgment of
noninfringement in favor of TuffStuff. That same day, the
court entered final judgment in accordance with the stipu-
lation. Thereafter, Hoist timely appealed. We have juris-
diction pursuant to 28 U.S.C § 1295(a)(1).
DISCUSSION
I.
Claim construction is ultimately an issue of law that
we review de novo. Teva Pharm. USA, Inc. v. Sandoz, Inc.,
574 U.S. 318, 325–26 (2015). “[W]hen the district court re-
views only evidence intrinsic to the patent (the patent
claims and specifications, along with the patent’s prosecu-
tion history), the judge’s determination will amount solely
to a determination of law, and the Court of Appeals will
review that construction de novo.” Id. at 331. We review
“regardless of the object or shape to which the common cen-
ter regards.” J.A. 9344. Mr. Lenz stated:
In other words, two bodies of dissimilar or non-
symmetrical shapes or sizes may nonetheless be
aligned in a concentric manner.
For example, a square and a triangle are con-
centrically aligned if they have a common center.
Similarly, the overall rotational motion of a body is
“concentric” arounds its center of rotation, or pole
of planar displacement, despite the fact that not all
points on said body need rotate precisely around
the same center of rotation. Rather, when consid-
ering the rotation of the body as a whole, the center
of rotation [is] an average point around which the
body moves.
J.A. 9344.
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12 HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS
the district court’s underlying factual findings for clear er-
ror. Id. at 325–33.
Claim terms are generally given their ordinary and
customary meaning as understood by a person of ordinary
skill in the art. Phillips v. AWH Corp., 415 F.3d 1303,
1312–13 (Fed. Cir. 2005) (en banc). The person of ordinary
skill in the art is “deemed to read the claim term not only
in the context of the particular claim in which the disputed
term appears, but in the context of the entire patent, in-
cluding the specification.” Id. at 1313.
II.
Hoist argues that the district court erred when it con-
strued the pivotally mounted/mounting terms to require
“overall movement” that is “generally concentric” and in
concluding that “concentric” is “more synonymous with cir-
cular” rather than meaning “having a common center.” Ap-
pellant’s Br. 38. 7 In so doing, Hoist contends, the district
7 We have considered and find no merit to TuffStuff’s
argument that Hoist withdrew from the litigation its alle-
gations of infringement with respect to certain patents and
claims prior to, and unrelated to, the stipulation. Hoist did
not officially “withdraw” its patents or claims, but merely
selected “representative” claims to present to the jury upon
the court’s request that it do so. J.A. 9273–74. Indeed, all
of the patents and claims at issue were included in the par-
ties’ joint proposed pre-trial conference order. Proposed Fi-
nal Pre-Trial Conf. Order, No. 5:17-cv-01388-AB-KK, Dkt.
No. 239, at 5 (C.D. Cal. Sept. 2, 2019). Further, the parties’
stipulation for entry of final judgment specifically identi-
fied each of the six Hoist patents at issue as having been
asserted. Joint Stipulation at 2, J.A. 27. Hoist thus did not
cease to litigate the patents or claims at issue, and they are
all properly before us on appeal. See Alcon Rsch. Ltd. v.
Barr Labs., Inc., 745 F.3d 1180, 1193 (Fed. Cir. 2014)
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HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS 13
court “improperly imported additional movement path re-
strictions” into its constructions of the pivotally
mounted/mounting terms. Id. at 42. Hoist asserts that,
while claims that recite a pivot axis do require “generally
concentric” movement about the pivot axis, 8 claims di-
rected to pivotally mounted/mounting have no requirement
of concentricity. Id. at 44–45. Finally, Hoist argues that
the court’s claim construction improperly limits movement
of the user support to the movement disclosed in the case
of the single pivot embodiment. Hoist states that “[i]f an
embodiment’s user support were mounted using one phys-
ical pivot and if that single pivot were fixed in place, the
movement of the user support would be only circular.” Id.
at 46. Hoist continues, however, that “[t]he Asserted
Claims are not so limited.” Id. Hoist concludes its argu-
ment by summarizing that:
The “pivotally mounted[/ing]” terms have no spe-
cial meaning beyond their plain meaning. The
specification and claim language make[ ] clear that
the claims merely require a pivotal mounting rela-
tive to or on the main frame, which is the plain
meaning. The term makes no further reference to,
and places no further limitation on, the shape or
nature of the resulting movement path.
Id. at 48.
TuffStuff responds that the district court correctly con-
strued the pivotally mounted/mounting terms. It states
that the district court properly construed “pivotally
mounted/mounting relative to the main frame” as
(citing SanDisk Corp. v. Kingston Tech. Co., 695 F.3d 1348,
1353 (Fed. Cir. 2012)).
8 E.g., claim 22 of the ’880 patent, claim 6 of the ’209
patent, claims 2, 8, and 23 of the ’949 patent, and claim 1
and its dependent claims 12 and 13 of the ’938 patent.
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14 HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS
requiring “pivotal motion” (i.e., generally concentric/circu-
lar motion) in relationship to the main frame. Appellee’s
Br. 47. TuffStuff argues that the patent specifications, the
“single best guide” to claim construction under Phillips,
415 F.3d at 1315, “overwhelmingly” support the proposi-
tion that a mounting structure that produces “pivotal” mo-
tion is one that produces a circular motion around a fixed
point. Appellee’s Br. 47, 50–51. In advancing that argu-
ment, TuffStuff points to several places in the ’209 and ’949
patent specifications where it is stated that the four-bar
pivot linkage “duplicates” the movement of a single pivot.
Id. at 8–10 & 48–50.
III.
We find no error in the district court’s claim construc-
tion. As noted above, claim terms are generally given their
ordinary and customary meaning as understood by a per-
son of ordinary skill in the art, who is “deemed to read the
claim term not only in the context of the particular claim
in which the disputed term appears, but in the context of
the entire patent, including the specification.” Phillips,
415 F.3d at 1313. Here, the specifications compel a con-
struction of “pivotally moun[ed]/[ing]” that requires gener-
ally concentric motion, where concentric is “more
synonymous with circular” than “having a common center.”
Hoist does not dispute that a single, fixed, physical
pivot accomplishes “generally circular” movement. See Ap-
pellant’s Br. 46. Indeed, Hoist’s expert, Mr. Lenz, con-
firmed that a single pivot mounted on a stationary base
would move in “essentially” a “circular motion” around its
pivot axis. J.A. 2618. Instead, however, Hoist points to the
four-bar linkage as an embodiment that it claims illus-
trates movement that is not generally circular and instead
“always includes a lateral component in addition to a piv-
otal component.” Oral Arg. at 4:19–5:05 (July 6, 2020),
available at http://oralarguments.cafc.uscourts.gov/de-
fault.aspx?fl=2020-1047.mp3.
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HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS 15
We do not read the specifications to encompass lateral
movement in the manner Hoist argues. Rather, the speci-
fications for the Hoist patents repeatedly state that the
four-bar linkage system “duplicates” the movement pattern
of a single point pivot, while providing additional location
options for the theoretical pivot axis of the four-bar linkage
that are not possible with a single point pivot. Specifically,
the specification of the ’209 patent states:
The advantage of the four-bar pivot system with
the theoretical pivot is that it duplicates the move-
ment pattern of a single point pivot that might nor-
mally be located in an area impossible to access due
to either structural or user interference, so that a
desired movement pattern may be achieved while
keeping the moving parts of the pivot mount be-
neath the user support.
’209 patent col. 6 ll. 42–48 (emphasis added); see also id. at
col. 7 ll. 7–11 (“[T]he four-bar pivoting linkage system . . .
duplicates the movement pattern of a single point pivot that
would otherwise be located underground, beneath the ma-
chine.”) (emphasis added); col. 13 ll. 56–62 (explaining that
a four-bar pivoting linkage system “can allow a desired piv-
oting movement to be achieved when a single pivot point
for producing the same motion may be located in an area
impossible to access due to either structural or user inter-
ference.”) (emphasis added).
The ’949 patent similarly states that a four-bar linkage
recreates the movement of a single pivot when a pivot can-
not be placed at the desirable location:
A four bar pivot linkage beneath the user support
can be arranged to produce movement equivalent to
a single pivot at an inaccessible location . . . .
’949 patent col. 2 ll. 10–15 (emphasis added).
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16 HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS
The theoretical pivot . . . is the position the user
support would pivot about if a single pivot were
used in order to obtain the same movement pattern.
Id. at col. 8 ll. 6–9 (emphasis added). The ’251 patent in-
corporates by reference the patent application that ulti-
mately issued as the ’949 patent and, in addition, uses the
terms “concentric” and “circular” synonymously. ’251 pa-
tent col. 1 ll. 53–55 (“Since the exercise arms had only one
pivot, they could only move in a concentric or circular pat-
tern.”).
Further, like the ’209 patent and the ’949 patent, the
’880 patent, the ’938 patent, and the ’440 patent each de-
scribe a theoretical pivot axis for the four-bar linkage that
is stationary, thereby resulting in generally concentric mo-
tion. E.g., ’880 patent col 9 l. 62–col. 10 l.1 & Figs. 1–4, ’938
patent col. 6 ll. 6–17, col. 7 ll. 55–57 & Figs. 1–4, ’440 patent
col. 9 ll. 52–55.
We note that, to the extent the movement of a four-bar
linkage is not identical to a single pivot, the district court
addressed this through its construction that the movement
need be “generally” concentric but need not be “perfectly
circular.” See J.A. 9439–40; August 27, 2019 Order at 7,
J.A. 101. At the same time, though, the Hoist specifica-
tions do not support a construction that goes beyond gen-
erally concentric, or generally circular, motion.
Based upon the foregoing, we hold that the district
court did not err in it claim construction. 9
9 Additionally, we find no error in the district court’s
decision to strike Mr. Lenz’s supplemental report. The
court struck the supplemental report in part because it de-
termined that Mr. Lenz interpreted the term “concentric”
too broadly. As we have affirmed the district court’s claim
Case: 20-1047 Document: 45 Page: 17 Filed: 10/02/2020
HOIST FITNESS SYSTEMS v. TUFFSTUFF FITNESS 17
CONCLUSION
Because we agree with the district court’s construction
of the pivotally mounted/mounting claim terms, we affirm
the judgment of noninfringement of the Hoist patents in
favor of TuffStuff.
AFFIRMED
construction, for the reasons discussed above, we also agree
that the report was properly stricken.