Roland Corporation v. Inmusic Brands, Inc.

N OTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
ROLAND CORPORATION,
Plaintiff-Cross-Appellant
v.
INMUSIC BRANDS, INC.,
Defendant-Appellant
______________________
2023-1327, 2023-1564, 2023-1565, 2023-1401
______________________
Appeals from the United States District Court for the
Southern District of Florida in No. 1:17-cv-22405-FAM,
Chief Judge Frederico A. Moreno.
______________________
Decided: March 27, 2025
______________________
N ATHAN K. K ELLEY , Perkins Coie LLP, Washington,
DC, argued for plaintiff-cross-appellant. Also represented
by G ENE WHAN L EE , New York, NY; VICTOR DE G YARFAS ,
Foley & Lardner LLP, Los Angeles, CA; L AURA G ANOZA,
Miami, FL.
CRAIG M. SCOTT , Hinckley, Allen & Snyder, LLP, Prov-
idence, RI, argued for defendant-appellant. Also repre-
sented by CHRISTINE K. BUSH ; L AUREL M. ROGOWSKI,
Boston, MA; J OSEPH W. BAIN, Shutts & Bowen LLP, West
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 2
Palm Beach, FL; J. MICHAEL J AKES , Finnegan, Henderson,
Farabow, Garrett & Dunner, LLP, Washington, DC.
______________________
Before L OURIE, REYNA , and CHEN, Circuit Judges.
CHEN, Circuit Judge.
Roland Corporation (Roland or Roland Japan) sued
inMusic Brands, Inc. (inMusic) for infringement of eight
patents relating to electronic drums and electronic cym-
bals: U.S. Patent Nos. 7,385,135 (’135 patent), 6,921,857
(’857 patent), 6,756,535 (’535 patent), 6,271,458 (’458 pa-
tent), 6,121,538 (’538 patent), 6,881,885 (’885 patent),
6,632,989 (’989 patent), and 7,459,626 (’626 patent) (collec-
tively, Asserted Patents). After construing disputed claim
terms, the district court granted summary judgment of
non-infringement of four of the Asserted Patents. The re-
maining four patents proceeded to a jury trial.1 After the
district court denied inMusic’s pre-trial and mid-trial
Daubert motions to exclude or strike the infringement tes-
timony of Roland’s technical expert, the jury found all
claims asserted at trial infringed and not invalid. The jury
awarded damages to Roland in the form of both lost profits
and reasonable royalties. After trial, the district court de-
nied (1) inMusic’s motions for judgment as a matter of law
(JMOL) or a new trial on liability and damages, and
(2) inMusic’s motion to bar Roland’s claims for infringe-
ment of the electronic cymbal patents due to equitable es-
toppel. inMusic appeals. The district court also denied
Roland’s motion to amend the judgment to add prejudg-
ment interest. Roland cross-appeals, challenging (1) the
denial of prejudgment interest, and (2) the district court’s
1 One of the patents for which the court granted
summary judgment of non-infringement also proceeded to
trial but on the issue of invalidity only. That patent is not
relevant to this appeal.
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 3
claim construction and grant of summary judgment of non-
infringement. The latter portion of Roland’s cross-appeal
is contingent on vacatur or reversal of the judgment of lia-
bility.
For the following reasons, we affirm in part, reverse in
part, vacate in part, dismiss in part, and remand. Regard-
ing inMusic’s appeal, we affirm the decision to not exclude
or strike the infringement testimony of Roland’s technical
expert, affirm the denial of JMOL or a new trial on in-
fringement and invalidity, and affirm the denial of inMu-
sic’s equitable estoppel defense. However, we reverse the
denial of a new trial on damages, vacate the damages
award, and remand for a new trial on damages. Regarding
Roland’s cross-appeal, we vacate the order denying pre-
judgment interest. And because we do not disturb the judg-
ment of liability, we dismiss the remaining, conditional
portion of Roland’s cross-appeal.
BACKGROUND
I. The Asserted Patents
A. The Drum Patents
Five of the Asserted Patents relate to electronic drums
and drumheads. These patents—the ’135 patent, ’857 pa-
tent, ’535 patent, ’458 patent, and ’538 patent (collectively,
Drum Patents)—share a common specification and are
each titled “Electronic Percussion Instrumental System
and Percussion Detecting Apparatus Therein.” The speci-
fication explains that prior art electronic drums containing
a “soft high-molecular compound material” covering the
percussion surface have a “repulsive feeling” when per-
cussed. ’458 patent col. 1 ll. 36–41.2 Furthermore, such
2 We cite to the ’458 patent as representative of the
Drum Patents’ common specification.
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 4
electronic drums produce “significant” acoustic percussion
noise. Id. col. 1 ll. 41–46.
Roland’s Drum Patents aim to solve those problems
with “a percussion detecting apparatus provided with a
head as the percussion surface which is excellent in percus-
sion feeling and in which the percussion sound is extremely
quiet in an electronic percussion instrumental system.” Id.
col. 1 l. 65 – col. 2 l. 4. Specifically, the patents teach a
percussion surface comprised of a “net-like raw material,”
which provides “extremely good percussion feeling” and
“extremely small” percussion sound “because of the elastic-
ity of the net-like raw material” that allows air to “pass[]
through the openings of stitches in” the material. Id. col. 2
ll. 31–37. The patents teach using two net layers. Id. col.
5 ll. 49–65; FIGS. 4–6. The patents also disclose using two
types of sensors: a “head sensor,” for “detecting percussion
applied to a head” of the electronic drum, and a “rim-shot
sensor,” for “detecting percussion applied to a rim” of the
electronic drum. Id. col. 4 ll. 47–56.
The Drum Patents contain various categories of claims.
Some of the claims asserted at trial recite no electronic
components at all. Claim 1 of the ’458 patent is representa-
tive of this category:
1. A head for an electronic percussion instrument,
the head comprising a frame and a net-like mate-
rial comprising first and second net members, each
supported by said frame, said net-like material
having openings through which air may pass.
Other Drum Patent claims asserted at trial recite a “sen-
sor” limitation. Independent claim 23 of the ’535 patent is
representative of this second category:
23. A percussion instrument, comprising:
a generally hollow body having an opening
into a body interior;
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 5
a generally flexible, net-like material ten-
sioned state across the opening of the gen-
erally hollow body, the net-like material
defining a percussion surface for receiving
a percussion impact, the net-like material
also having openings of a size sufficient to
allow air to pass therethrough, upon receiv-
ing a percussion impact on the percussion
surface; and
a sensor supported by said generally hollow
body, for providing an electronic signal in
response to a percussion impact on the per-
cussion surface of the generally flexible,
net-like material.
Yet a third category of claims—not asserted at trial, but
relevant on appeal—recite a “transducer” limitation. Some
of these claims further recite a “head sensor.” For example,
independent claim 13 of the ’535 patent recites “a head sen-
sor comprising a cushioning member and a transducer.”
B. The Cymbal Patents
The remaining three Asserted Patents relate to elec-
tronic cymbals. Two of these patents—the ’885 patent and
’989 patent (collectively, Cymbal Patents)—share a com-
mon specification and are each titled “Electronic Pad With
Vibration Isolation Features.”3 The patents explain that
electronic cymbals “imitating” acoustic cymbals have been
widely used. ’885 patent col. 1 ll. 44–45.4 An electronic
cymbal “detects the striking position and the striking force
of a stick or the like by means of a striking sensor, controls
a sound source based on the detected striking position and
3 The third patent relating to electronic cymbals, the
’626 patent, is not at issue on appeal.
4 We cite to the ’885 patent as representative of the
Cymbal Patents’ common specification.
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 6
striking force[,] and thereby produces a cymbal sound (elec-
tronic percussion sound).” Id. col. 1 ll. 45–50. However,
the prior art “electronic cymbal formed out of hard resin
disadvantageously has a problem in that the striking sen-
sation is different from that of an acoustic cymbal.” Id. col.
2 ll. 5–8. Further, it was “difficult to detect a striking po-
sition (region)” and “difficult to detect a striking force with
high accuracy” in the prior art cymbals. Id. col. 2 ll. 10–22.
The Cymbal Patents aim to solve those problems. Id.
col. 2 ll. 32–34. The disclosed cymbals permit vibration to
attenuate “relatively promptly, so that even if th[e] elec-
tronic pad . . . is continuously struck, it is possible to accu-
rately detect the striking position and the striking force for
each strike.” Id. col. 6 ll. 35–38. Additionally, “the appear-
ance of the upper surface is similar to that of the acoustic
cymbal, ensuring a good striking sensation.” Id. col. 6 ll.
39–41. The patents also disclose a “piezoelectric sensor
[that] can accurately detect vibration generated . . . after
the surface and the peripheral edge of the surface of the
electronic pad . . . are struck.” Id. col. 7 ll. 59–62.
Independent claim 28 of the ’885 patent is representa-
tive of the Cymbal Patent claims asserted at trial:
28. An electronic pad receiving a strike, detecting
the strike and outputting a signal representative of
the strike comprising:
a frame having a striking surface with a pe-
ripheral edge portion;
a cover covering the striking surface of the
frame;
a striking sensor provided on a part of, but
not the entire peripheral edge portion of
the frame, the striking sensor for detecting
the strike transmitted to the frame through
the cover; and
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a jack affixed to the frame and electrically
coupled to the striking sensor for output-
ting signals from the striking sensor, the
jack having an opening of a receiving space
for receiving an electrical plug, the opening
of the receiving space facing in a direction
away from the part of the peripheral edge
portion of the frame having the striking
sensor.
II. Factual and Procedural Background
A. Roland’s Lawsuit
Roland is a Japanese corporation and electronic instru-
ment manufacturer. Roland first made noise about its
competitor inMusic’s alleged infringement in 2011, years
before Roland brought this lawsuit.
On March 11, 2011, Roland wrote to inMusic accusing
certain electronic cymbals of infringing Roland’s Cymbal
Patents.5 After some back-and-forth between the parties,
inMusic responded on September 19, 2011, disputing in-
fringement of the identified cymbals but also stating that
it was “currently discontinuing” the cymbals. J.A. 15272–
75. On October 5, 2011, Roland wrote back that it did “not
intend to pursue this matter” if inMusic discontinued the
cymbals as represented and “does not engage in other in-
fringing activities.” J.A. 15334–35.
On February 3, 2015, Roland wrote to inMusic, again
accusing it of infringement and expressing Roland’s “sur-
prise[]” to find certain inMusic products on display at a
trade show. J.A. 15337–39. inMusic responded on
5 Roland’s pre-suit communications were actually
with Alesis, a brand purchased by inMusic in 2011 and un-
der which inMusic sells electronic instruments. For sim-
plicity, we refer to only inMusic.
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February 12, 2015, stating that the identified cymbal prod-
uct line was “radically redesigned after 2011” and that
inMusic believed it had “Roland’s implied consent” to sell
these cymbals. J.A. 15266–67.
Roland then sued inMusic in August 2016 for infringe-
ment of the Asserted Patents in the United States District
Court for the Central District of California, which trans-
ferred the case to the United States District Court for the
Southern District of Florida. Roland’s amended complaint
accused multiple products sold under the Alesis brand, in-
cluding electronic drums, the redesigned electronic cym-
bals, and kits including both.
B. Claim Construction and Summary Judgment
Several of the district court’s claim constructions are
pertinent to this appeal.
As relevant to the Cymbal Patents, the magistrate
judge recommended construing the claim term “striking
sensor” as “a device that detects vibration resulting from a
strike to the strike surface of the frame.” Roland Corp. v.
inMusic Brands, Inc., No. 17-CV-22405, 2019 WL 5291175,
at *18–19 (S.D. Fla. Aug. 1, 2019) (Markman R. & R.). Ro-
land had initially proposed construing the term, in part, as
“[a] device that detects pressure,” but Roland “agree[d] with
[inMusic’s] construction to the extent it would be limited to
‘a device that detects vibration resulting from a strike.’” Id.
at *18 (emphasis added).
As relevant to the Drum Patents, the magistrate judge
recommended construing the terms “net-like material” and
“net member” as “[a]n element that is similar in appear-
ance to an open meshed fabric with openings through
which air passes sufficient to reduce sound when the ele-
ment is percussed.” Id. at *12–13. The magistrate judge
recommended construing the term “sensor” as “head sen-
sor,” rejecting that it should “be construed so broadly as to
include the rim-shot sensor.” Id. at *16–17. Finally, the
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magistrate judge recommended construing the claim terms
“transducer” and “cushioning material”/“cushioning mem-
ber,” in relevant part, as limited to a single transducer and
a single cushioning material/member, respectively. Id. at
*3–9.
The district judge affirmed and adopted the claim con-
struction report and recommendation and overruled both
parties’ objections thereto. Roland Corp. v. inMusic
Brands, Inc., No. 17-CV-22405, 2022 WL 278967, at *1
(S.D. Fla. Jan. 31, 2022). Based on the district court’s con-
structions, the magistrate judge recommended granting
partial summary judgment of non-infringement, including
as to all asserted claims of three Drum Patents (the ’538
patent, ’857 patent, and ’135 patent) and all asserted
claims of the ’626 patent. Roland Corp. v. inMusic Brands,
Inc., No. 17-CV-22405, 2022 WL 1018349, at *4–5, *19
(S.D. Fla. Feb. 11, 2022) (Summary Judgment R. & R.).
The district judge affirmed and adopted the summary judg-
ment report and recommendation and overruled both par-
ties’ objections thereto. Roland Corp. v. inMusic Brands,
Inc., No. 17-CV-22405, 2022 WL 1015588, at *1 (S.D. Fla.
Apr. 5, 2022). Final judgment of non-infringement of those
claims was entered accordingly. J.A. 136.
C. Daubert Motions
The parties filed several pre-trial Daubert motions to
exclude expert witness testimony. In relevant part, inMu-
sic sought to exclude the opinions of Roland’s damages ex-
pert, Suzanne Heinemann, and Roland’s technical expert,
Dr. Paul Lehrman. The magistrate judge denied both mo-
tions, see Roland Corp. v. inMusic Brands, Inc., No. 17-CV-
22405, 2022 WL 22907270, at *1 (S.D. Fla. Aug. 22, 2022);
Roland Corp. v. inMusic Brands, Inc., No. 17-CV-22405,
2022 WL 22907271, at *1 (S.D. Fla. Aug. 22, 2022), and the
district judge overruled inMusic’s objections with respect
to the latter, Roland Corp. v. inMusic Brands, Inc., No. 17-
CV-22405, 2022 WL 22907230, at *1 (S.D. Fla. Sept. 27,
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 10
2022). inMusic did not object to and does not appeal the
failure to exclude the opinions of Ms. Heinemann.
Dr. Lehrman testified at trial regarding his infringe-
ment opinions. During cross-examination, Dr. Lehrman
testified several times to an incorrect understanding of the
all-elements rule.6 See J.A. 20041–43; see, e.g., id. at 20042
(“Q. So if you have fewer than all of those elements, or
what your counsel described as limitations, that are found
in the accused product, your opinion is that the accused
product is infringing. Is that your testimony here today?
A. Yes.”). inMusic then moved to strike Dr. Lehrman’s tes-
timony and for reconsideration of the district judge’s order
overruling inMusic’s objections to the magistrate judge’s
order declining to exclude the opinions of Dr. Lehrman.
While that motion was pending, Roland called Dr. Lehr-
man for re-direct examination. Dr. Lehrman at first re-
peated his incorrect understanding of the all-elements rule,
but after re-reading a portion of his supplemental expert
report he ultimately testified that “[a]ll limitations must be
present to establish infringement.” J.A. 20176–77. The
district court then denied inMusic’s motion. Roland Corp.
v. inMusic Brands, Inc., No. 17-CV-22405, 2022 WL
22907231, at *1 (S.D. Fla. Nov. 18, 2022); J.A. 20496–97.
D. Trial
The district court held a ten-day jury trial in October
and November 2022. Roland asserted claims 1–2, 4, 6–7,
9, and 17 of the ’458 patent, claims 19–21 and 23 of the ’535
6 A tenet of patent law, “[t]he all-elements rule is
that an accused device must contain every claimed element
of the invention or the equivalent of every claimed ele-
ment.” Kustom Signals, Inc. v. Applied Concepts, Inc., 264
F.3d 1326, 1333 (Fed. Cir. 2001) (citing Warner-Jenkinson
Co. v. Hilton Davis Chem. Co., 520 U.S. 17, 29 (1997)).
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patent, claims 1–3 of the ’989 patent, and claims 28–34 of
the ’885 patent.
The district court required each party to prepare a
claim chart to show the jury their respective infringement
and invalidity positions. See J.A. 11780–81 (inMusic’s
chart); J.A. 11784–98 (Roland’s Chart). The court contem-
plated providing a jury instruction relating to the charts
but decided not to do so after inMusic objected. However,
the court still offered to provide the parties’ charts to the
jury. Roland agreed and its chart went to the jury. inMu-
sic, again, objected and declined the court’s offer, so its
chart did not go to the jury.
At the close of evidence in the liability phase of the
trial, inMusic moved under Federal Rule of Civil Procedure
50(a) for JMOL of non-infringement and invalidity. The
district court denied both motions. J.A. 20491, 20494. Sub-
sequently, the jury returned a verdict that found all as-
serted claims infringed and not invalid. J.A. 124–28.7
The district court then commenced the damages phase
of the trial on Thursday, November 17, 2022—the week be-
fore Thanksgiving. The court faced two scheduling hurdles
with the upcoming holiday. Roland’s damages expert,
Ms. Heinemann, was scheduled to fly out of the country for
a pre-planned vacation beginning Friday, November 18,
and the jury foreperson was also scheduled to leave for va-
cation the week of Thanksgiving. See J.A. 20129; J.A.
20774. In order to accommodate Ms. Heinemann and com-
plete the damages trial with the same jury as for liability,
the court sharply limited the parties’ time with their dam-
ages experts: twenty minutes for direct examination,
7 The jury additionally found not invalid claims 3–6,
10–11, and 17–21 of the ’626 patent. J.A. 124–28.
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fifteen minutes for cross-examination, and five minutes for
re-direct examination. See J.A. 20129; J.A. 20774, 20862.8
During her brief direct examination, Ms. Heinemann
testified that Roland was entitled to $2.7 million in lost
profits for a portion of inMusic’s infringing drum kit sales.
Ms. Heinemann’s calculation included the lost profits of
both Roland and its wholly owned subsidiary, Roland Cor-
poration U.S. (Roland U.S.). For the remaining infringing
drum and cymbal sales, Ms. Heinemann testified that Ro-
land was entitled to $1.9 million in reasonable royalties.
inMusic moved under Rule 50(a) for JMOL on damages
at the close of Roland’s damages case. The district court
denied the motion with leave to renew after inMusic’s re-
buttal case. J.A. 20946, 20953. At the close of its rebuttal
case, inMusic filed the renewed motion, which the court de-
nied as moot when the jury reached a damages verdict
while oral argument on the motion was ongoing. See J.A.
133; J.A. 21158, 21162–63. The jury awarded damages to
Roland in accordance with Ms. Heinemann’s opinion: $2.7
million in lost profits and $1.9 million in reasonable royal-
ties, for a total damages award of $4.6 million. J.A. 131–
32.
E. Post-Trial Motions
Following trial, inMusic filed Rule 50(b) renewed mo-
tions for JMOL or, in the alternative, for a new trial, on
liability and damages. The court denied both motions with-
out an opinion and entered final judgment accordingly. See
Roland Corp. v. inMusic Brands, Inc., No. 17-CV-22405,
2022 WL 22907232, at *1 (S.D. Fla. Dec. 28, 2022); J.A.
135.
8 Each party ran slightly over the court’s time limi-
tations in their examinations of Ms. Heinemann. See J.A.
20840, 20862.
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The district court then denied Roland’s motion to
amend the judgment to add prejudgment interest. Roland
Corp. v. inMusic Brands, Inc., No. 17-CV-22405, 2023 WL
2441356, at *1 (S.D. Fla. Jan. 20, 2023) (Prejudgment In-
terest Order). Finally, the district court denied inMusic’s
motion to bar Roland’s claims of infringement of the Cym-
bal Patents due to equitable estoppel. Roland Corp. v.
inMusic Brands, Inc., No. 17-CV-22405, 2023 WL 2424146,
at *1–3 (S.D. Fla. Feb. 28, 2023) (Equitable Estoppel Or-
der).
S TANDARD OF REVIEW
We review a denial of a motion for JMOL, for a new
trial, or for reconsideration under the law of the appropri-
ate regional circuit. Wis. Alumni Rsch. Found. v. Apple
Inc., 905 F.3d 1341, 1346 (Fed. Cir. 2018); Del. Valley Flo-
ral Grp., Inc. v. Shaw Rose Nets, LLC, 597 F.3d 1374, 1379
(Fed. Cir. 2010). We also apply the law of the regional cir-
cuit to “evidentiary rulings [that] raise procedural issues
not unique to patent law.” Odetics, Inc. v. Storage Tech.
Corp., 185 F.3d 1259, 1276 (Fed. Cir. 1999). Here, the re-
gional circuit is the Eleventh Circuit.
The Eleventh Circuit reviews denial of JMOL de novo,
“viewing the evidence in the light most favorable to the
non-moving party.” Howard v. Walgreen Co., 605 F.3d
1239, 1242 (11th Cir. 2010). “The motion should be granted
only ‘when the plaintiff presents no legally sufficient evi-
dentiary basis for a reasonable jury to find for him on a
material element of his cause of action.’” Id. (citation omit-
ted); see also Fed. R. Civ. P. 50(a)(1). “While ‘the non-mo-
vant must put forth more than a mere scintilla of evidence
suggesting that reasonable minds could reach differing ver-
dicts,’ a jury’s verdict ‘will not be overturned unless no ra-
tional trier of fact could have reached the same conclusion
based upon the evidence in the record.’” Mamani v.
Sánchez Bustamante, 968 F.3d 1216, 1230 (11th Cir. 2020)
(citations omitted).
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The Eleventh Circuit reviews a district court’s decision
on a motion for a new trial under the abuse of discretion
standard. Torres v. First Transit, Inc., 979 F.3d 876, 881
(11th Cir. 2020). “A district court abuses its discretion if it
applies an incorrect legal standard, applies the law in an
unreasonable or incorrect manner, follows improper proce-
dures in making a determination, or makes findings of fact
that are clearly erroneous.” Id. (citation omitted). A court
may grant a motion for a new trial under Federal Rule of
Civil Procedure 59 if it determines that “the verdict is
against the weight of the evidence, that the damages are
excessive, or that, for other reasons, the trial was not fair.”
McGinnis v. Am. Home Mortg. Servicing, Inc., 817 F.3d
1241, 1254 (11th Cir. 2016) (citation omitted). “Although a
trial judge cannot weigh the evidence when confronted
with a motion [for JMOL], in a motion for a new trial the
judge is free to weigh the evidence.” Id. (citation omitted).
“Under Eleventh Circuit law, we review evidentiary
rulings for abuse of discretion.” Omega Pats., LLC v.
CalAmp Corp., 13 F.4th 1361, 1368 (Fed. Cir. 2021). The
Eleventh Circuit also reviews a district court’s denial of a
motion for reconsideration for an abuse of discretion. Cor-
win v. Walt Disney Co., 475 F.3d 1239, 1254 (11th Cir.
2007).
D ISCUSSION
I. Failure to Exclude or Strike Dr. Lehrman’s Testimony
We begin with inMusic’s challenge to the district
court’s decision to admit Dr. Lehrman’s infringement opin-
ions. A trial court’s decision to admit or exclude expert tes-
timony under Daubert is reviewed for abuse of discretion.
Gen. Elec. Co. v. Joiner, 522 U.S. 136, 139 (1997).
“Daubert requires that trial courts act as ‘gatekeepers’
to ensure that speculative, unreliable expert testimony
does not reach the jury.” McCorvey v. Baxter Healthcare
Corp., 298 F.3d 1253, 1256 (11th Cir. 2002); see Fed. R.
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Evid. 702. inMusic alleges that Dr. Lehrman’s infringe-
ment testimony was unreliable for several reasons.
First, inMusic takes issue with Dr. Lehrman’s testi-
mony that expressed an incorrect understanding of the all-
elements rule. It is axiomatic that “[t]o show infringement,
the plaintiff must establish that the accused device in-
cludes every limitation of the claim or an equivalent of each
limitation.” Dolly, Inc. v. Spalding & Evenflo Cos., 16 F.3d
394, 397 (Fed. Cir. 1994). But Dr. Lehrman’s testimony to
the contrary was irrelevant to his infringement opinions.
Over many pages of testimony, Dr. Lehrman testified that
each limitation of every claim asserted at trial was satis-
fied by the accused products. See J.A. 19918–40, 19947–
94, 19999–20040. Dr. Lehrman was asked during his lim-
itation-by-limitation analysis, “if all the limitations of a
claim had been satisfied or found in [the] accused products,
what does that mean?” Id. at 19939. He answered, “[t]hat
means that the products are an infringement of these
claims.” Id.; see also, e.g., id. at 20027 (“This shows that
Claims 31 and 32 are both satisfied, all limitations, and
thereby the products are infringing these two claims.”).
Dr. Lehrman clearly expressed to the jury that his “conclu-
sion was that all the accused products infringed on the pa-
tents” because he demonstrated that “all the limitations of
all the claims were met by infringing products.” Id. at
20173–74. And Dr. Lehrman ultimately corrected his un-
derstanding of the all-elements rule. See id. at 20177. The
district court did not abuse its discretion by failing to strike
the testimony of Dr. Lehrman on this basis.
Second, regarding the Drum Patents, inMusic makes
several arguments relating to Dr. Lehrman’s testimony
vis-à-vis the “head sensor” limitation. This claim limita-
tion, which recites “a head sensor comprising a cushioning
member and a transducer,” see, e.g., ’535 patent claim 13,
is not contained in any claim asserted at trial. It is distinct
from the “sensor” limitation of the asserted claims. Alt-
hough the district court construed “sensor” as “head
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 16
sensor”—as opposed to a rim-shot sensor—the magistrate
judge expressly noted that the court did not construe “sen-
sor” as requiring “a cushioning member/material and a sin-
gle transducer.”9 Summary Judgment R. & R., 2022 WL
1018349, at *12. We reject inMusic’s attempt to conflate
different limitations of different claims.
Third, regarding the Cymbal Patents, inMusic asserts
that Dr. Lehrman’s methodology of testing for the “striking
sensor” limitation was unreliable. The court construed
that term as requiring “a device that detects vibration re-
sulting from a strike to the strike surface of the frame.”
Markman R. & R., 2019 WL 5291175, at *19. During trial,
jurors were shown a video of an experiment that Dr. Lehr-
man testified was performed to determine whether the
striking sensor limitation, as construed by the court, was
present in the accused cymbals. See J.A. 20015–19.
Dr. Lehrman testified that when the relevant part of the
accused cymbals was hit, “the bottom line on the oscillo-
scope turn[ed] into a squiggly line, which indicates that a
signal is output from that sensor, from the cymbal to the
oscilloscope,” and that demonstrates that the striking sen-
sor satisfies the court’s definition as “a device that detects
vibration.” Id. at 20017–19; see also id. at 19988.10
Dr. Lehrman further testified that the striking sensor is a
9 Notably, inMusic did not object to the magistrate
judge’s proposed construction of “sensor” and does not ap-
peal the court’s construction of that limitation.
10 We note that we must rely on what the trial tran-
script reveals regarding the video shown to the jury, for the
video has not been made available to us. “When parties
rely on demonstratives to present evidence . . . to the jury,
it is their burden to assure that the record captures the
substance of the data so presented. We can not guess at
what the jury saw.” Whitserve, LLC v. Comput. Packages,
Inc., 694 F.3d 10, 32 n.16 (Fed. Cir. 2012).
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“piezo,” which “generates an electric current when it is sub-
ject to pressure or vibration or force,” id. at 19989, and ex-
plained that “vibration can be a single cycle in a change in
pressure,” J.A. 20185. inMusic has offered no persuasive
reason why Dr. Lehrman was unable to reliably conclude
that the testing detected vibration.
In short, none of inMusic’s arguments persuade us that
the district court abused its discretion in declining to ex-
clude or strike the infringement testimony of Dr. Lehr-
man.11
II. JMOL of Non-Infringement
inMusic contends that it was entitled to JMOL of non-
infringement. We disagree. “Determination of infringe-
ment is a question of fact, which, in the context of a jury
trial, we review for substantial evidence.” Union Carbide
Chems. & Plastics Tech. Corp. v. Shell Oil Co., 308 F.3d
1167, 1177 (Fed. Cir. 2002).
11 inMusic also cites as an indication that the district
court relinquished its gatekeeping role to the jury the
court’s statement that “maybe they want to do their own
Daubert analysis, see? It will be interesting to see and be
the gatekeeper.” J.A. 20790. Under Daubert, the court, not
the jury, must assess the reliability of expert testimony.
See Chapman v. Procter & Gamble Distrib., LLC, 766 F.3d
1296, 1306 (11th Cir. 2014). It would appear the court
merely intended to make an offhand joke. Regardless, we
are not convinced that the district court handed off its gate-
keeping role to the jury. The magistrate judge and district
judge considered inMusic’s pre-trial Daubert motion to ex-
clude Dr. Lehrman, and the district court judge reconsid-
ered that motion during trial. And as explained above, we
conclude that the court did not abuse its discretion in deny-
ing that motion.
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inMusic begins by harking back to its arguments re-
garding Dr. Lehrman’s testimony that misunderstood the
all-elements rule. True, “when an expert witness’[s] state-
ment of the law is incorrect, that view of the law cannot be
relied upon to support the verdict.” Integra Lifesciences I,
Ltd. v. Merck KGaA, 496 F.3d 1334, 1342 (Fed. Cir. 2007).
But Roland does not attempt to support the verdict of in-
fringement with Dr. Lehrman’s misstatement of the all-el-
ements rule. Roland’s case-in-chief and Dr. Lehrman’s
ultimate infringement opinion relied on a correct under-
standing of the all-elements rule, i.e., that every limitation
of the asserted claims was practiced by all the accused
products. See supra Discussion Section I; see, e.g., J.A.
20173–74. Moreover, the district court correctly instructed
the jury on the all-elements rule. See J.A. 20665–66.
inMusic also challenges the sufficiency of the evidence
supporting the jury’s finding that the accused products sat-
isfy two particular limitations of the asserted claims: the
“head sensor” limitation and the “striking sensor” limita-
tion.
We reject inMusic’s challenge to the “head sensor” lim-
itation. As explained above with respect to inMusic’s
Daubert challenge, inMusic confuses the “head sensor” lim-
itation, pertaining to Drum Patent claims not asserted at
trial, with the “sensor” limitation, pertaining to Drum Pa-
tent claims that were asserted at trial. To the extent inMu-
sic’s argument can be taken as challenging the “sensor”
limitation, a reasonable jury could have concluded, based
on Dr. Lehrman’s testimony, that the accused drums sat-
isfy that limitation. Dr. Lehrman identified a particular
component of the accused drums as the sensor and ex-
plained that “it generates a signal when it reads vibration
or force.” J.A. 19960; see also id. at 19962, 19974–75,
19977.
Regarding the striking sensor limitation of the Cymbal
Patent claims asserted at trial, Dr. Lehrman walked the
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 19
jury through a video of testing performed on accused cym-
bals, which Dr. Lehrman testified demonstrated a striking
sensor that detects vibration. See J.A. 19988–89, 20015–
19; supra Discussion Section I. Opposing counsel cross-ex-
amined Dr. Lehrman as to whether the experiment actu-
ally tested for vibration, attempting to impeach him with
his deposition testimony. J.A. 20165–67. inMusic points
to no opposing testimony of its own expert witness. This
dispute was a factual issue to be decided by the jury, which
reasonably found infringement of the striking sensor limi-
tation.
Accordingly, we affirm the district court’s denial of
JMOL of non-infringement.
III. New Trial on Infringement
inMusic next argues that even if it was not entitled to
JMOL of non-infringement, it was at least entitled to a new
trial. The basis for this argument is the district court’s de-
cision to provide Roland’s infringement claim chart to the
jury for use during deliberations.
The parties’ claim charts are what courts commonly re-
fer to as “demonstrative exhibits,” “pedagogical devices,” or
“illustrative aids.” See, e.g., Baugh ex rel. Baugh v. Cu-
prum S.A. de C.V., 730 F.3d 701, 707 (7th Cir. 2013); Fed.
R. Evid. 107 Advisory Comm. Notes.12 Illustrative aids, not
typically themselves admitted into evidence, are “used to
aid the jury in its understanding of the evidence that has
already been admitted.” Baugh, 730 F.3d at 707. Roland’s
claim chart was not admitted as substantive evidence. Ra-
ther, the issue before us is whether the district court
12 Because of recognized confusion over the term
“demonstrative,” we instead employ the term “illustrative
aid,” now used by Federal Rule of Evidence 107. See
Baugh, 730 F.3d at 706–07; Fed. R. Evid. 107 Advisory
Comm. Notes.
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abused its discretion in permitting the jury to use the non-
admitted claim chart during deliberations. See United
States v. Robinson, 872 F.3d 760, 780 n.5 (6th Cir. 2017)
(recognizing the distinction between the “issue of whether
demonstrative aids may be admitted into evidence” and the
issue of “whether non-admitted demonstrative exhibits
may be provided to the jury during deliberations”).
This court faces a peculiar situation. During the pen-
dency of this appeal, Federal Rule of Evidence 107 govern-
ing the use of illustrative aids went into effect. See U.S.
Supreme Court Order, Order Amending Federal Rules of
Evidence (Apr. 2, 2024), https://www.supremecourt.gov/or-
ders/courtorders/frev24_9o6b.pdf (“The foregoing amend-
ments to the Federal Rules of Evidence shall take effect on
December 1, 2024, and shall govern in all proceedings
thereafter commenced and, insofar as just and practicable,
all proceedings then pending.”). If we were to determine
that it is “just and practicable” for Rule 107 to govern, the
rule provides that an illustrative aid “must not be provided
to the jury during deliberations unless: (1) all parties con-
sent; or (2) the court, for good cause, orders otherwise.”
Fed. R. Evid. 107(b). If we were to determine otherwise,
we would apply pre-Rule 107 case law on the issue. How-
ever, we are aware of no Eleventh Circuit case addressing
this precise question. If the relevant regional circuit has
not spoken on a legal issue, “we must predict how that
court would decide the issue in light of such criteria as the
decisions of that circuit’s district courts, other circuits’ de-
cisions, and public policy.” Badalamenti v. Dunham’s, Inc.,
896 F.2d 1359, 1362 (Fed. Cir. 1990). Accordingly, we
would be required to predict how the Eleventh Circuit
would decide an obsolete issue that in the future would be
governed by Rule 107. Yet we need not resolve these issues
because any error in providing Roland’s claim chart to the
jury was harmless. See Robinson, 872 F.3d at 780 (declin-
ing to decide whether a district court may provide a non-
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 21
admitted illustrative aid to the jury under pre-Rule 107 law
because any error was harmless).
Roland’s claim chart was substantively duplicative of
and consistent with admitted evidence. See id. (harmless
error where illustrative “aids were based on evidence that
the jury was otherwise allowed to see or hear”); cf. United
States v. Malol, 476 F.3d 1283, 1292 (11th Cir. 2007)
(harmless error in admitting a summary chart under Rule
1006 because “[t]he summary chart merely repeated the
same type of evidence as already presented”). The illustra-
tive aid, like Dr. Lehrman’s testimony, largely maps each
element of the asserted claims to a numbered part of the
accused products, in both tabular and pictorial formats.
And certain portions of the aid are quite similar to other
claim charts that were admitted as trial exhibits. Compare,
e.g., J.A. 11789–90, with J.A. 16249–51. inMusic com-
plains about a discrepancy: the admitted exhibits annotate
part 350 as a “percussion detector/head sensor,” whereas
the illustrative aid removes that annotation and identifies
a different component, part 330, as a “sensor.” Compare
J.A. 11786, with J.A. 16264, 16271. But inMusic again con-
fuses the “sensor” and “head sensor” limitations and ig-
nores that part 330 was identified as the claimed sensor by
Dr. Lehrman’s testimony and the admitted exhibits. See,
e.g., J.A. 16271; J.A. 19960. Accordingly, inMusic cannot
show that it was prejudiced.
Because Roland’s claim chart did not substantively and
materially differ from admitted testimonial and documen-
tary evidence, any error by the district court in providing
Roland’s chart to the jury was harmless and does not enti-
tle inMusic to a new trial.
IV. Invalidity
inMusic argues that it was entitled to JMOL of invalid-
ity, or in the alternative a new trial on invalidity, of certain
claims of the two Drum Patents asserted at trial: claims
1–2, 4, and 17 of the ’458 patent and claims 19–21 of the
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 22
’535 patent (collectively, mesh head claims). These claims
are directed to drumheads that lack any limitations recit-
ing electronic components. inMusic contends that each of
two prior art references anticipate the mesh head claims:
Ishida13 and Hayashi14. Anticipation requires the patent
challenger to show by clear and convincing evidence that
“each element of the claim at issue, properly construed, is
found in a single prior art reference.” Zenith Elecs. Corp.
v. PDI Commc’n Sys., Inc., 522 F.3d 1348, 1363 (Fed. Cir.
2008). Anticipation is a question of fact that we review for
substantial evidence. ATEN Int’l Co. v. Uniclass Tech. Co.,
932 F.3d 1364, 1367 (Fed. Cir. 2019).
inMusic argues that its technical expert, Dr. Harri Ky-
tomaa, testified that Ishida and Hayashsi both teach a
drumhead that meets every limitation of claims 19–21 of
the ’535 patent.15 Claim 19, from which claims 20–21 de-
pend, requires “a net-like material comprising multiple net
members, . . . said net-like material having openings
through which air may pass.” ’535 patent claim 19. As
construed by the district court, the “net-like material” and
“net member” terms require “[a]n element that is similar
in appearance to an open meshed fabric with openings
through which air passes sufficient to reduce sound when
the element is percussed.” Markman R. & R., 2019 WL
5291175, at *13.
Regarding Ishida, Roland counters by pointing to the
testimony of one of its fact witnesses and a co-inventor of
the Drum Patents, Masato Katsuda. While he worked for
Roland, and before prosecution of the Drum Patents,
Mr. Katsuda wrote an internal memorandum concerning
13 Japan Pat. No. H2-117569 (J.A. 13925–39).
14 U.S. Pat. No. 4,828,907 (J.A. 15419–25).
15 inMusic contends that the analysis does not differ
for the remaining mesh head claims from the ’458 patent.
See Appellant’s Response & Reply Br. 37–38.
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 23
Ishida and other references. See J.A. 17220–28; J.A.
19560–61. At trial, Mr. Katsuda affirmed his deposition
testimony that Ishida “does not reveal that air can pass
through,” and he testified that Ishida does not teach two
layers of mesh. J.A. 19593–94. As for Hayashi, Roland re-
lies on cross-examination testimony of Dr. Kytomaa. On
cross-examination, Dr. Kytomaa admitted that “the em-
phasis of Hayashi is not sound reduction” but rather “the
selection of different fibrous materials to influence the
sound of the diaphragm.” J.A. 20346 (emphases added).
Dr. Kytomaa could not “remember whether Hayashi says
anything about sound reduction.” Id.
Thus, the jury heard evidence that Ishida and Hayashi
do not disclose certain limitations of the mesh head claims.
Namely, the limitation requiring multiple net members, for
Ishida, and the limitations requiring air to pass through
the drumhead sufficient to reduce sound, for both Ishida
and Hayashi. Viewing the evidence in the light most favor-
able to Roland, as we must, a rational jury could have found
that inMusic failed to prove anticipation by those two ref-
erences. See Mamani, 968 F.3d at 1230; see, e.g., E.I. du
Pont De Nemours & Co. v. Unifrax I LLC, 921 F.3d 1060,
1075 (Fed. Cir. 2019) (“Although [the patentee] did not call
an expert to testify as to the differences between [the prior
art reference] and the asserted claims, there was substan-
tial documentary evidence and cross-examination testi-
mony from [the patent challenger’s] expert for the jury to
conclude that . . . [the reference] does not anticipate the as-
serted claims . . . .”). We also conclude the jury verdict was
not against the weight of the evidence such that the district
court abused its discretion in declining to grant inMusic a
new trial on invalidity.
V. Damages
We turn next to damages. Damages for patent in-
fringement are governed by 35 U.S.C. § 284, which pro-
vides, in relevant part, that “the court shall award the
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 24
claimant damages adequate to compensate for the infringe-
ment, but in no event less than a reasonable royalty for the
use made of the invention by the infringer.” Accordingly,
“[o]ur case law recognizes two measures of damages: lost
profits and reasonable royalties.” Warsaw Orthopedic, Inc.
v. NuVasive, Inc., 778 F.3d 1365, 1374 (Fed. Cir. 2015), va-
cated sub nom., Medtronic Sofamor Danek USA, Inc. v.
NuVasive, Inc., 577 U.S. 1099 (2016), opinion reinstated in
relevant part, 824 F.3d 1344, 1346 (Fed. Cir. 2016). “We
review the jury’s determination of the amount of damages,
an issue of fact, for substantial evidence.” Arctic Cat Inc.
v. Bombardier Recreational Prods. Inc., 876 F.3d 1350,
1369 (Fed. Cir. 2017) (citation omitted).
inMusic argues that it is entitled to JMOL, or in the
alternative a new trial, on damages for both lost profits and
reasonable royalties. As explained below, we agree that
inMusic is entitled to a new trial on both categories of dam-
ages.
A. Lost Profits
inMusic first takes issue with the jury’s award of $2.7
million in lost profits. Based on the testimony of Roland’s
damages expert, Ms. Heinemann, the jury awarded Roland
not only its own lost profits but also those of its wholly
owned subsidiary, Roland U.S. During the damages period
for which Roland claimed lost profits, Roland sold elec-
tronic drums to Roland U.S., which in turn sold the drums
to retailers in the United States. Ms. Heinemann’s testi-
mony calculated a single, consolidated lost profits figure for
the two entities in the first instance, and offered an “alter-
nate calculation” in the event Roland is not entitled to the
lost profits of Roland U.S. J.A. 20834.
“To recover lost profits, the patentee bears the burden
of proof to show a ‘reasonable probability that, “but for” in-
fringement, it would have made the sales that were made
by the infringer.’” Presidio Components, Inc. v. Am. Tech.
Ceramics Corp., 875 F.3d 1369, 1380 (Fed. Cir. 2017)
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 25
(citation omitted). “Whether lost profits are legally com-
pensable in a particular situation is a question of law that
we review de novo,” and we review the jury’s lost profits
award for substantial evidence. Siemens Med. Sols. USA,
Inc. v. Saint-Gobain Ceramics & Plastics, Inc., 637 F.3d
1269, 1287–88 (Fed. Cir. 2011).
The general rule is that “a patentee may not claim, as
its own damages, the lost profits of a related company.”
Warsaw, 778 F.3d at 1375. Roland attempts to claim as its
own the lost profits of Roland U.S. under an exception
known as “inexorable flow.” Under that theory, which has
been previously argued to this court, the subsidiary’s prof-
its flow inexorably or inherently to the plaintiff parent com-
pany. See Mars, Inc. v. Coin Acceptors, Inc., 527 F.3d 1359,
1367 (Fed. Cir. 2008), mandate recalled and amended on
other grounds, 557 F.3d 1377 (Fed. Cir. 2009). In Mars, we
affirmed a grant of summary judgment to the defendant on
the plaintiff’s claim of lost profits because the record could
not support a finding that the wholly owned subsidiary’s
profits flowed inexorably to the plaintiff. Id. at 1364, 1367.
Because we concluded that the subsidiary’s profits did not
in fact flow inexorably to the plaintiff, we expressly de-
clined to “decide whether a parent company can recover on
a lost profits theory when profits of a subsidiary actually
do flow inexorably up to the parent.” Id. at 1367. This
court has not since addressed whether inexorable flow is a
legally cognizable theory of lost profits. Nor must we do so
now, for like the Mars court, we conclude that Roland did
not offer sufficient evidence to support a factual finding of
inexorable flow of profits.
Roland argues that it established inexorable flow based
on a single sentence of testimony from Roland’s Senior
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 26
Executive Officer and Roland U.S.’s Executive Vice Presi-
dent, Naoyuki Tamura16:
Q. What happens to the profits of Roland U.S. on
those sales of mesh drums?
[A.] Because Roland U.S. is a 100 percent owned
subsidiary of Roland Japan, the profit it made will
be returned to Roland Japan in the form of divi-
dends.
J.A. 20887 (objection omitted) (emphasis added).
Mr. Tamura’s conclusory testimony provided no basis for
the jury to find that Roland U.S.’s profits inherently flowed
to Roland during the relevant period other than the fact
that Roland U.S. is a wholly owned subsidiary. In Mars,
we rejected the notion that such a corporate relationship,
without more, was sufficient to recover the subsidiary’s lost
profits. Mars, 527 F.3d at 1367. Mr. Tamura did not, for
example, explain who controlled Roland U.S.’s distribution
of profits or what corporate controls were in place to ensure
that Roland U.S.’s profits became those of Roland Japan.
Nor did Roland present documentary evidence of Roland’s
and Roland U.S.’s historical financial information showing
an unwavering flow of profits. We need not delineate what
types of evidence would be sufficient to establish inexorable
flow. Suffice it to say, under Mars, the testimony presented
at trial falls short of substantial evidence to support the
jury’s lost profits award.
Roland argues that even if it is not entitled to the lost
profits of Roland U.S., it is still entitled to that portion of
the award comprising its own lost profits. However, the
jury rendered a single lost profits award that did not sepa-
rate Roland’s profits from Roland U.S.’s. See J.A. 131–32.
And we cannot say that the jury necessarily accepted or
16 Ms. Heinemann did not herself offer an opinion on
inexorable flow. See J.A. 20852.
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 27
would have accepted Ms. Heinemann’s alternative calcula-
tion accounting for only Roland’s own lost profits.
Ms. Heinemann presented the jury with a single lost prof-
its figure of $2.7 million—as opposed to presenting each
company’s respective profits as separate inputs that
summed to $2.7 million—and then Ms. Heinemann offered
the jury a calculation that “removed the profit related to
Roland U.S.” J.A. 20834. On the resulting figure,
Ms. Heinemann equivocated between “1.3 million, a little
higher,” “like 1.35 million,” and “1.3 million.” J.A. 20834,
20840. Although the lost profits figure “need not be proven
with unerring precision,” the amount of Roland’s own lost
profits is a question of fact that was not decided by the jury
and cannot be decided by us. Standard Havens Prods., Inc.
v. Gencor Indus., Inc., 953 F.2d 1360, 1374 (Fed. Cir. 1991)
(citation omitted). Accordingly, we must vacate the jury’s
entire lost profits award.
B. Reasonable Royalties
The jury also awarded Roland $1.9 million in reasona-
ble royalties. At trial, Ms. Heinemann used a hypothetical
negotiation approach to arrive at that figure. She relied on
exclusively several of Roland’s prior licenses to the Drum
Patents and Cymbal Patents to opine that Roland would
have been entitled to a reasonable royalty of $20 per drum-
head and $2 per cymbal. We conclude that Ms. Heine-
mann’s testimony does not provide sufficient evidence to
support the jury’s reasonable royalty award for either cat-
egory of the Asserted Patents.
1. The Drum Patents
A patentee may rely on its prior licenses to prove a rea-
sonable royalty, so long as the patentee properly accounts
for apportionment so that it “seek[s] only those damages
attributable to the infringing features.” Omega Pats., LLC
v. CalAmp Corp., 13 F.4th 1361, 1376–77 (Fed. Cir. 2021);
see also ResQNet.com, Inc. v. Lansa, Inc., 594 F.3d 860, 869
(Fed. Cir. 2010) (citing Georgia-Pacific Corp. v. U.S.
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 28
Plywood Corp., 318 F. Supp. 1116, 1120 (S.D.N.Y. 1970)).
“[W]hen a sufficiently comparable license is used as the ba-
sis for determining the appropriate royalty, further appor-
tionment may not necessarily be required.” Omega, 13
F.4th at 1376–77 (citation omitted). But the patentee bears
the burden of proving damages, including the burden to
prove that the licenses it relies on are “sufficiently compa-
rable.” Id. at 1377 (citation omitted). We have “stressed
that comparisons of past patent licenses to the infringe-
ment must account for ‘the technological and economic dif-
ferences’ between them.” Wordtech Sys., Inc v. Integrated
Networks Sols., Inc., 609 F.3d 1308, 1320 (Fed. Cir. 2010)
(citation omitted).
Ms. Heinemann relied on three licenses to support her
$20-per-drumhead reasonable royalty for the ’458 patent
and the ’535 patent. These licenses were: (1) a license to
Hart Dynamics Incorporated (Hart), which includes a li-
cense for certain claims of the ’458 patent and the ’538 pa-
tent as part of a settlement agreement, see J.A. 15703–20;
(2) a license to Pintech USA, Inc. (Pintech) for certain
claims of the ’458 patent and the ’538 patent, see J.A.
15721–35; and (3) a license to Guitar Center, Inc. (Guitar
Center) for the ’535 patent, the ’538 patent, the ’857 patent,
and the ’135 patent, see J.A. 16918–26. Each of the agree-
ments licensed only single-layer mesh drumheads, in con-
trast to the double-layer mesh technology at issue in the
parties’ hypothetical negotiation. We agree with inMusic
that Ms. Heinemann failed in various ways to appropri-
ately connect these licenses to the parties’ hypothetical ne-
gotiation.
First, in addition to the ’458 patent and ’535 patent, the
licenses include the three Drum Patents that were not as-
serted at trial. “[A]llegedly comparable licenses may cover
more patents than are at issue in the action,” however,
“[t]estimony relying on licenses must account for such dis-
tinguishing facts when invoking [the licenses] to value the
patented invention.” Ericsson, Inc. v. D-Link Sys., Inc., 773
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 29
F.3d 1201, 1227 (Fed. Cir. 2014). Ms. Heinemann failed to
even mention this difference on direct examination, and on
cross-examination she testified that the Guitar Center li-
cense “covers at least one of the patents from the mesh fam-
ily.” J.A. 20853. It is not enough that Ms. Heinemann
“merely identified” a difference in the patents covered by
one of the three licenses, if her testimony could even be de-
scribed as having accomplished that. Omega, 13 F.4th at
1381. As this court has previously reasoned, “[w]hat’s ut-
terly lacking is evidence that [Roland] met its obligation to
‘account for such distinguishing facts’ in invoking the li-
censes to value” the two infringed patents. Id. (emphasis
added) (citation omitted); see also id. at 1380–81 (conclud-
ing that the patentee failed to adequately account for addi-
tional patents in licenses relied on to value a single patent).
Second, Roland granted the Hart license in the context
of settling litigation with Hart. “We have previously ex-
plained that prior settlements can be relevant to determin-
ing damages.” Elbit Sys. Land & C4I Ltd. v. Hughes
Network Sys., LLC, 927 F.3d 1292, 1299 (Fed. Cir. 2019).
But “whether in using a settlement agreement at all or in
drawing the appropriate lessons from the particular settle-
ment for the case in which it is being used, relevant circum-
stances—such as similarities and differences in
technologies and market conditions and the state of the
earlier litigation when settled—must be carefully consid-
ered” and “any differences in circumstances must be
soundly accounted for.” Id. at 1299–30. Ms. Heinemann
acknowledged on cross-examination that the Hart license
was part of a settlement agreement reached shortly before
trial and testified that “the context of that just needs to be
considered.” J.A. 20855–56. But Ms. Heinemann stopped
short, failing to explain whether and how she accounted for
the context of the litigation between Roland and Hart and
the respective positions of the parties leading up to trial.
Cf. LaserDynamics, Inc. v. Quanta Comput., Inc., 694 F.3d
51, 77–78 (Fed. Cir. 2012) (district court abused its
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discretion in admitting plaintiff’s prior settlement agree-
ment that “was executed shortly before a trial” in which the
licensee “would have been at a severe legal and procedural
disadvantage given the numerous harsh sanctions imposed
on it by the district court.”); Elbit, 927 F.3d at 1300 (ex-
pert’s testimony relying on a prior settlement supported a
damages verdict because the expert “accounted for the fact
that the [agreement] was a settlement prompted by litiga-
tion”).
Third, Ms. Heinemann failed to coherently explain how
she derived a $20 per drumhead royalty rate from the rates
of the three single-layer mesh licenses. Ms. Heinemann
testified that the three licenses fell within a range of a “12
to $14” royalty rate. J.A. 20837. The Pintech license pro-
vided for a royalty of 10% of net sales, which Ms. Heine-
mann converted to a $9.24 per-unit rate. J.A. 15723; J.A.
20836–37. Ms. Heinemann then testified that “[t]here was
a dispute between Pintech and Roland,” and “Roland actu-
ally expected them to pay a little bit higher, something
around $12.66.” J.A. 20837. But Ms. Heinemann failed to
explain the basis for the $12.66 figure, the circumstances
underlying Roland’s uncorroborated expectation of receiv-
ing a $12.66 royalty instead of $9.24, and why that ex-
pected rate was more probative than the $9.24 rate that
Ms. Heinemann testified Roland was “actually paid” under
the agreement. Id.
Ms. Heinemann’s testimony regarding the Hart license
fares no better. That agreement set a royalty of 6% of gross
sales, from which Ms. Heinemann calculated a per-unit
rate of $16.93. J.A. 15704–05; J.A. 20837. But without ex-
planation, Ms. Heinemann concluded that this license,
along with the others, fell within a range of $12–14.17
17 Ms. Heinemann additionally testified that the
Hart license provided for royalties on “replacement parts”
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 31
Moreover, the license to Guitar Center provided on its face
for a $12 per-unit royalty rate—at the bottom end of the
$12–14 range—leaving no explanation for how Ms. Heine-
mann arrived at the upper end of that range for the single-
layer mesh licenses. J.A. 16919. Royalty rates that “ap-
pear[] to have been plucked from thin air . . . cannot be the
basis for a reasonable royalty calculation.” Finjan, Inc. v.
Blue Coat Sys., Inc., 879 F.3d 1299, 1312 (Fed. Cir. 2018).
In addition to inadequately supporting the $12–14
range for single-layer mesh drumheads, Ms. Heinemann
failed to support her ultimate $20 rate for the double-layer
mesh at issue. Ms. Heinemann testified that Roland had
never before licensed double-layer mesh, so she relied on
Roland’s rejected offer to Guitar Center of a 50% premium
to license double-layer mesh. J.A. 20837–38. In Whitserve,
LLC v. Computer Packages, Inc., we “acknowledge[d] pro-
posed licenses may have some value for determining a rea-
sonable royalty in certain situations.” 694 F.3d 10, 29–30
(Fed. Cir. 2012). Yet we also observed that the value of a
proposed license may be limited “by, inter alia, the fact that
patentees could artificially inflate the royalty rate by mak-
ing outrageous offers.” Id. at 30. Here, even if we were to
agree that this rejected license offer is probative evidence
(which we need not decide), Ms. Heinemann never ex-
plained how, upon applying the 50% premium to her pro-
posed $12–14 range for single-layer mesh, she arrived at a
reasonable royalty of $20.
For each of these reasons, Roland “did not present to
the jury a basis in fact to associate the royalty rates used
in prior licenses to the particular hypothetical negotiation
at issue in this case.” Omega, 13 F.4th at 1381 (cleaned
for the licensed drumheads. J.A. 20837. We see no basis
for this in the Hart license. But even if the Hart license did
encompass replacement parts, Ms. Heinemann failed to ex-
plain how she accounted for that.
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up). Because Ms. Heinemann offered a consolidated rea-
sonable royalty opinion for infringement of both the as-
serted Drum Patents and Cymbal Patents, and the jury
accordingly rendered a single reasonable royalty award, we
must vacate the jury’s entire award. Nevertheless, we also
address a fatal flaw in Ms. Heinemann’s reasonable royalty
analysis for the Cymbal Patents because this legal issue is
likely to arise again on remand. See Trans-World Mfg.
Corp. v. Al Nyman & Sons, Inc., 750 F.2d 1552, 1566 (Fed.
Cir. 1984) (addressing an issue likely to recur in a damages
retrial).
2. The Cymbal Patents
For a reasonable royalty to the Cymbal Patents,
Ms. Heinemann similarly relied on several of Roland’s
prior licenses to arrive at a rate of $2 per cymbal.
Ms. Heinemann testified that she applied that rate to
inMusic’s cymbal sales from August 2010 through June
2021 to calculate her reasonable royalty figure. See J.A.
20873–74. On cross-examination, Ms. Heinemann admit-
ted she was unaware that the accused cymbals considered
and found to be infringing by the jury were the cymbals
that inMusic redesigned in 2011. See id. inMusic argues
that, accordingly, Ms. Heinemann “overstated her lump
sum royalty opinion because it included cymbal units da-
ting back to 2010.” Appellant’s Br. 58. We agree, and for
this reason as well vacate the award of reasonable royal-
ties.
“As we have held, a reasonable royalty ‘cannot include
activities that do not constitute patent infringement, as pa-
tent damages are limited to those “adequate to compensate
for the infringement.”’” Enplas Display Device Corp. v.
Seoul Semiconductor Co., Ltd., 909 F.3d 398, 411 (Fed. Cir.
2018) (citation omitted). In Enplas, we vacated the jury’s
reasonable royalty award under similar circumstances.
There, the patentee’s expert “appl[ied] a royalty to lenses
that were neither accused of infringement nor shown to
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 33
infringe.” Id. at 412. We explained that the expert’s dam-
ages calculation, based in part on non-infringing sales of
non-accused products, “cannot support the jury’s damages
award, for § 284 and our precedent proscribe awarding
damages for non-infringing activity.” Id. at 411–12.
Roland does not dispute that Ms. Heinemann included
in her calculation pre-redesign cymbal sales that were not
found by the jury to infringe. Rather, it argues that
“Ms. Heinemann addressed [those sales] during her cross-
examination and even provided the jury the difference be-
tween her 2010 and 2011 calculations based on her review
of inMusic’s monthly sales data.” Cross-Appellant’s Br. 58.
Ms. Heinemann testified that “there were about 20,000
cymbals that were sold from August 2010 through March
2011,” which amounts to “about $40,000 of royalties.” J.A.
20873. But the jury did not award damages less $40,000.
Further, Ms. Heinemann did not account for the precise
timing of the redesign in 2011. Ms. Heinemann attempted
to dismiss that issue on cross-examination by asserting
that “you would just need to look at [inMusic’s monthly
sales] data,” J.A. 20874, but the jury was not provided with
that data. The only basis for the jury’s award was
Ms. Heinemann’s original opinion calculating $1.9 million
of reasonable royalties, including non-infringing cymbal
sales dating back to August 2010. As in Enplas, Roland
cannot ensnare non-infringing sales into its damages
award.18
18 Further, Ms. Heinemann testified that she used a
hypothetical negotiation date of January 2010, rather than
the time in 2011 when inMusic’s infringement of the Cym-
bal Patents began. See J.A. 20874–76; LaserDynamics, 694
F.3d at 75 (“In general, the date of the hypothetical negoti-
ation is the date that the infringement began.”). On re-
mand, Roland must account for the correct hypothetical
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ROLAND CORPORATION v. INMUSIC BRANDS, INC. 34
C. Remedy
The parties dispute the appropriate remedy for dam-
ages. inMusic argues for JMOL of no damages, while Ro-
land argues for a new trial. We believe the fairer option is
to afford Roland a new trial on both lost profits and reason-
able royalties. The district court imposed its time con-
straints on examination of the parties’ damages experts
shortly before Roland began its examination of Ms. Heine-
mann. Roland’s damages case may have suffered as a re-
sult of the unusually brief time it was afforded for expert
examination. We therefore remand for a new trial on dam-
ages. Given that the district court will not face the same
scheduling conflicts that led to the strict time limitations
in the first trial, we expect that the court will afford the
parties suitable time for examination of their experts in the
retrial.19
negotiation date “to discern the value of the patented tech-
nology to the parties in the marketplace when infringe-
ment began.” Id. at 76 (remanding for a new trial on
damages pursuant to the correct hypothetical negotiation
date). This includes consideration of whether, in light of
the correct hypothetical negotiation date, there was a
“changing technological and financial landscape in the
market” that needs to be accounted for in relying on Ro-
land’s prior licenses to value the patented technology. Id.
at 78.
19 The district judge believed that the time it afforded
was “a long time,” comparing it to the “very popular” 12-
minute-long TED Talks. J.A. 20774. The length of a TED
Talk, however, is not an appropriate benchmark for the
presentation of expert testimony in a trial, let alone a pa-
tent trial with millions of dollars in damages at stake.
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VI. Equitable Estoppel
The last issue raised by inMusic is the district court’s
denial of inMusic’s motion to bar the Cymbal Patent in-
fringement claims due to equitable estoppel. In order to
succeed on the defense, inMusic bore the burden of proving
by a preponderance of the evidence, among other elements
not relevant here, that “the patentee, through misleading
conduct (or silence), le[d] the alleged infringer to reasona-
bly infer that the patentee does not intend to enforce its
patent[s] against the alleged infringer.” Radio Sys. Corp.
v. Lalor, 709 F.3d 1124, 1130 (Fed. Cir. 2013); see A.C.
Aukerman Co. v. R.L. Chaides Constr. Co., 960 F.2d 1020,
1041–43, 1046 (Fed. Cir. 1992) (en banc), abrogated on
other grounds by SCA Hygiene Prods. Aktiebolag v. First
Quality Baby Prods., LLC, 580 U.S. 328 (2017). We review
the court’s decision whether to apply equitable estoppel for
abuse of discretion. Radio Sys., 709 F.3d at 1130.
inMusic’s theory of estoppel is that Roland knew about
inMusic’s redesigned cymbals in 2011 but did not complain
to inMusic about that design until 2015. See Equitable Es-
toppel Order, 2023 WL 2424146, at *2. Before the court
was competing trial testimony of David Gill, an inMusic
employee, and Ted Rittmaster, outside counsel for Roland.
Mr. Gill testified that in 2011 he and other inMusic person-
nel had a call with Mr. Rittmaster, in which inMusic de-
scribed its redesign and which left inMusic with “the
opinion that [it] was going to be left alone.” Id. (citation
omitted); see J.A. 19830–31. Mr. Rittmaster, on the other
hand, testified that in 2011 inMusic “represented to Roland
that the . . . inMusic cymbals were being discontinued” and
that Mr. Rittmaster never expressed to inMusic in writing
or orally that Roland was not going to enforce the Cymbal
Patents. J.A. 19635, 19667; see Equitable Estoppel Order,
2023 WL 2424146, at *3. Without “additional evidence to
corroborate either side’s description of events,” the compet-
ing testimony “essentially boil[ed] down to a ‘he said, [he]
said’ situation.” Equitable Estoppel Order, 2023 WL
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2424146, at *3 (second alteration in original). Thus, the
court found that inMusic failed to prove by a preponder-
ance that “Roland knew, in 2011, that inMusic’s redesigned
cymbal products infringed Roland’s Cymbal Patents” and
that “Roland misled inMusic into believing that inMusic’s
infringement was permissible.” Id.
inMusic argues that the district court’s ruling conflicts
with its separate order denying prejudgment interest to
Roland. There, the court found that “Roland knew of inMu-
sic’s accused cymbals as early as 2011” and “had approved
the redesigned cymbals during a call with Mr. Gill in
2011.” Prejudgment Interest Order, 2023 WL 2441356, at
*1. But the court’s order did not cite any evidence for that
finding nor even mention the testimony of Mr. Rittmaster.
By contrast, when the court considered and weighed the
relevant evidence in its equitable estoppel decision, it was
unconvinced that Roland had misled inMusic. See Equita-
ble Estoppel Order, 2023 WL 2424146, at *2–3. We cannot
say that the district court abused its discretion in denying
inMusic’s equitable estoppel defense.20
VII. Prejudgment Interest
Finally, we turn to Roland’s cross-appeal. Roland ap-
peals the district court’s denial of Roland’s motion to
amend the judgment to add prejudgment interest. “We
20 In its equitable estoppel order, the district court
also cited to a declaration by Mr. Rittmaster. Equitable Es-
toppel Order, 2023 WL 2424146, at *3. That same day, and
in the very next docket entry, the court struck Mr. Rittmas-
ter’s declaration as outside the trial record. See J.A. 224;
J.A. 13233. The court erred by considering the stricken
declaration. However, the error was harmless, for the
court’s reliance on the parties’ competing trial testimony
alone demonstrates that the court did not abuse its discre-
tion in denying inMusic’s equitable estoppel defense.
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review a district court’s denial of prejudgment interest in
patent cases for an abuse of discretion.” Kaufman v. Mi-
crosoft Corp., 34 F.4th 1360, 1373 (Fed. Cir. 2022).
We have previously explained that an “award of pre-
judgment interest is ‘the rule, not the exception.’” Energy
Transp. Grp., Inc. v. William Demant Holding A/S, 697
F.3d 1342, 1358 (Fed. Cir. 2012) (citation omitted); see also
Gen. Motors Corp. v. Devex Corp., 461 U.S. 648, 655–57
(1983); 35 U.S.C. § 284. Still, “it may be appropriate to
limit prejudgment interest, or perhaps even deny it alto-
gether, where the patent owner has been responsible for
undue delay in prosecuting the lawsuit.” Gen. Motors, 461
U.S. at 657. In order to “show that delay was undue, a de-
fendant must, at least generally, show that it was preju-
diced.” Kaufman, 34 F.4th at 1375.
The district court denied prejudgment interest after
finding that “Roland knew of inMusic’s accused cymbals as
early as 2011, yet Roland waited until 2015 to raise com-
plaints about inMusic’s cymbals’ configuration, and waited
until August 2016 to sue.” Prejudgment Interest Order,
2023 WL 2441356, at *1. The court concluded that Ro-
land’s delay was undue and “economically prejudiced
inMusic because inMusic expanded its cymbals by incorpo-
rating them into newly launched kits while under the un-
derstanding that Roland had approved the redesigned
cymbals during a call with Mr. Gill in 2011.” Id. The court
reasoned that “had Roland not sat on its hands during this
years-long delay, inMusic could have taken remedial steps
and could have dedicated resources to other non-infringing
designs.” Id. For two separate reasons, however, the dis-
trict court abused its discretion in denying prejudgment
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interest, requiring us to vacate its prejudgment interest or-
der.21
First, the finding of undue delay based on the alleged
call with Mr. Gill cannot be squared with the district
court’s findings and analysis of the evidence in its order
denying inMusic’s equitable estoppel defense. There, as ex-
plained above, the court found that the competing trial tes-
timony of Mr. Gill and Mr. Rittmaster was insufficient for
inMusic to prove Roland’s knowledge of the infringing cym-
bals in 2011. Equitable Estoppel Order, 2023 WL 2424146,
at *3; see supra Discussion Section VI. Though the district
court might permissibly rely on other evidence to find that
Roland independently learned of the redesign prior to pros-
ecuting its suit against inMusic (and hence, there could be
undue delay to justify denying prejudgment interest, but
no misleading conduct for purposes of equitable estoppel),
the court cited no such evidence (or any evidence) in deny-
ing prejudgment interest. On remand, the court may not
again limit or deny prejudgment interest to Roland absent
analysis of how other evidence in the trial record supports
a finding of undue delay.
Second, even if Roland knew of the redesign, the dis-
trict court relied on an incorrect standard for prejudice.
The court reasoned that inMusic was prejudiced because it
expanded its cymbal line before Roland brought suit,
whereas inMusic “could have” instead explored non-
21 We have already concluded we must vacate the
damages award. Unless and until the district court makes
another award of damages to Roland, there are currently
no damages on which to base prejudgment interest. Nev-
ertheless, we address the issues relating to the court’s de-
nial of prejudgment interest because they are likely to arise
again upon another award of damages on remand. See
Trans-World Mfg. Corp. v. Al Nyman & Sons, Inc., 750 F.2d
1552, 1566 (Fed. Cir. 1984).
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infringing cymbal designs. Prejudgment Interest Order,
2023 WL 2441356, at *1. But speculation about what
inMusic “could have [done] to not infringe” the Cymbal Pa-
tents, without “evidence that it would have” done so, is in-
sufficient to demonstrate prejudice. Kaufman, 34 F.4th at
1375. The key question is whether, in the absence of Ro-
land’s delay (if any), inMusic would have abandoned or fur-
ther altered its cymbal line to avoid infringement. Each
party argues undisputed facts that support an inference in
their respective favor of what inMusic would have done.
inMusic points to the fact that, when first accused of in-
fringement by Roland in 2011, inMusic discontinued its in-
itial cymbal design and redesigned the cymbals. See
Appellant’s Response & Reply Br. 48–49. Roland points to
the fact that inMusic simply continued to sell the accused
cymbals even after Roland brought the instant action. See
Cross-Appellant’s Reply Br. 7. We remand for the district
court to resolve this factual dispute—specifically, what
inMusic would have done absent any delay by Roland—and
to determine whether inMusic demonstrated prejudice suf-
ficient to limit or deny prejudgment interest to Roland.22
CONCLUSION
We have considered the parties’ remaining arguments
but find them unpersuasive. Because we affirm the judg-
ment of liability, we dismiss the portion of Roland’s cross-
appeal conditioned on our vacating or reversing on liability.
Thus, we affirm in part, reverse in part, vacate in part,
22 The district court’s denial of prejudgment interest
was also based solely on Roland’s purported knowledge of
the accused cymbals and delay in prosecuting its suit with
respect to infringement of the Cymbal Patents. On re-
mand, to the extent that Roland seeks, and the jury
awards, separate damages for infringement of the Drum
Patents, the district court should not limit or deny prejudg-
ment interest with respect to that category of damages.
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dismiss in part, and remand for a new trial on damages
consistent with this opinion.
AFFIRMED-IN-PART, REVERSED-IN-PART,
VACATED-IN-PART, DISMISSED-IN-PART, AND
REMANDED
COSTS
No costs.
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