Nexstep, Inc. v. Comcast Cable Communications, LLC

United States Court of Appeals
for the Federal Circuit
______________________
NEXSTEP, INC.,
Plaintiff-Appellant
v.
COMCAST CABLE COMMUNICATIONS, LLC,
Defendant-Cross-Appellant
______________________
2022-1815, 2022-2005, 2022-2113
______________________
Appeals from the United States District Court for the
District of Delaware in No. 1:19-cv-01031-RGA, Judge
Richard G. Andrews.
______________________
Decided: October 24, 2024
______________________
PAUL J. ANDRE, Kramer Levin Naftalis & Frankel LLP,
Redwood Shores, CA, argued for plaintiff-appellant. Also
represented by CHRISTINA M. FINN, JAMES R. HANNAH, LISA
KOBIALKA; AARON M. FRANKEL, CRISTINA MARTINEZ,
CARLOS J. TIRADO, New York, NY.
THOMAS SAUNDERS, Wilmer Cutler Pickering Hale and
Dorr LLP, Washington, DC, argued for defendant-cross-
appellant. Also represented by AMY K. WIGMORE; WILLIAM
F. LEE, GEORGE FANTON MANLEY, SARAH B. PETTY, Boston,
MA; LAUREN MATLOCK-COLANGELO, New York, NY; MARY
VIRGINIA SOOTER, Denver, CO.
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 2
______________________
Before REYNA, TARANTO, and CHEN, Circuit Judges.
Opinion for the court filed by Circuit Judge CHEN.
Opinion concurring-in-part and dissenting-in-part filed by
Circuit Judge REYNA.
CHEN, Circuit Judge.
NexStep, Inc., (NexStep) appeals from a final judgment
that Comcast Cable Communications, LLC, (Comcast) did
not infringe U.S. Patent Nos. 8,885,802 (’802 patent) and
8,280,009 (’009 patent). After construing the term “VoIP”
in the ’802 patent, the district court granted summary
judgment of non-infringement. The ’009 patent proceeded
to a jury trial, and the jury found no literal infringement
but infringement under the doctrine of equivalents.
Following a post-trial motion by Comcast, the district court
found NexStep’s proof inadequate and granted judgment as
a matter of law of non-infringement of the ’009 patent. On
appeal, NexStep argues that the district court erred in its
construction of VoIP in the ’802 patent and further erred in
granting Comcast’s motion for judgment as a matter of law
for the ’009 patent. We reject those challenges and affirm
as to both issues. In light of that disposition, we do not
reach NexStep’s contentions related to damages or
Comcast’s conditional cross-appeal related to validity.
I.
NexStep filed suit in the United States District Court
for the District of Delaware asserting infringement of nine
patents, including the ’802 and ’009 patents. Following
Markman proceedings, the district court granted summary
judgment of non-infringement of the ’802 patent, adopting
Comcast’s view that VoIP was a term of art with a meaning
that excluded NexStep’s sole infringement theory. At the
same time, the district court denied Comcast’s summary
judgment motion relating to the ’009 patent; that motion
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 3
argued that the ’009 patent was ineligible under 35 U.S.C.
§ 101.
After a jury trial for the ’009 patent, the jury found that
the asserted patent claims were infringed under the
doctrine of equivalents. In response to the verdict form’s
question addressing literal infringement, the jury found
that the ’009 patent was not literally infringed.
Following post-trial motions under Federal Rule of
Civil Procedure 50(b), the district court set aside the jury
verdict and granted judgment of non-infringement as a
matter of law, finding the evidentiary record inadequate to
support infringement under the doctrine of equivalents.
NexStep, Inc. v. Comcast Cable Commc’ns, LLC, No. 19-cv-
1031, 2022 WL 1503922, at *7 (D. Del. May 12, 2022)
(JMOL Decision). The district court primarily reasoned
that the testimony of NexStep’s expert, Dr. Ted Selker, was
too conclusory to sustain the verdict. Describing portions
of Dr. Selker’s testimony as “word salad,” the district court
concluded that Dr. Selker’s testimony lacked the specificity
and analysis required by our precedent. Id. Among other
things, the district court concluded that Dr. Selker failed to
identify specific components in the accused products and
failed to offer a reasoned basis for concluding that those
specific components were equivalent to the relevant claim
limitations. Id. at *5–7. Thus, the court entered final
judgment of non-infringement with respect to the ’802 and
’009 patents. The final judgment further reflected the
district court’s summary judgment ruling rejecting
Comcast’s affirmative defense that the ’009 patent is
ineligible under 35 U.S.C. § 101.
NexStep appeals, and Comcast conditionally cross-
appeals. We have jurisdiction over NexStep’s appeal under
28 U.S.C. § 1295(a)(1), and we do not reach Comcast’s
cross-appeal.
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 4
II.
A.
The ’802 patent is directed to a “digital butler” that
controls consumer electronics based on audio data. ’802
patent Abstract; id. col. 16 ll. 20–30. Broadly speaking, the
digital butler relies on two components: a handheld device
capable of receiving audio input and a separate “master
device” (or console)1 for processing that input. The audio-
controlled handheld device “needs only limited computing
capabilities” because it is “tethered” to the more robust
master device supporting it. Id. claim 7, col. 1 ll. 34–43,
col. 2 ll. 56–63. The ’802 patent describes its handheld
device as a “remote control,” which “may resemble a
handheld personal computer (HPC), a palm-held personal
computer (PPC or PDA) or a smart phone.” Id. Title, col. 1
ll. 39–41.
Several of the claims—including claims 1 and 7, the
only claims at issue in this appeal—further specify how the
audio data must be processed in the claimed system. Claim
1 is representative:
1. A remote control device with slaved audio input,
the device including:
a wireless link transceiver;
at least one slaved audio input built into the
remote control;
a navigation control built into the remote control;
1 The specification uses the phrase “console” and
“master device” interchangeably, as do the parties in their
briefing before us.
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 5
hardware resources coupled between the wireless
link transceiver, the slaved audio input and the
navigation control;
a stack running on the hardware resources and
exchanging packets with a master device; and
an encoder logic running on the hardware
resources, logically coupled to the stack, adapted to
encode signals from the slaved audio input into a
remote control audio format, and adapted to send
audio packets in the remote control audio format to
the master device;
wherein the remote control depends on the master
device to transcode input from the slaved audio
input to VoIP from the remote control device format
and relies on the master device to respond to
control signals sent by the remote control device in
the packets.
Id. claim 1 (emphasis added). Claim 1 requires that the
remote control can “encode” the audio data from a user’s
voice into “a remote control audio format,” and that the
remote can “send audio packets in the remote control audio
format to the master device.” Id. Then, the master device
performs a further conversion on the audio packets: “the
remote control depends on the master device to transcode”
the audio input “from the remote control device format” to
“VoIP.” Id. Finally, the master device “respond[s] to control
signals sent by the remote control device in” the audio
packets. Id. In short, the remote control can receive audio
data and transmit it to the master device, and—after
transcoding the audio data to VoIP—the master device can
decide how to respond to that audio data and acts
accordingly. Id.
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B.
The term “VoIP” forms the basis of NexStep’s appeal for
the ’802 patent. The district court2 construed VoIP in light
of the parties’ agreement that VoIP is a well-established
term of art within the relevant industry. Specifically, the
parties “agreed that [VoIP] is an industry standard term,
and the patentee did not deviate from the plain and
ordinary meaning of the term as understood by a person of
ordinary skill in the art.” NexStep, Inc. v. Comcast Cable
Commc’ns, LLC, No. 19-cv-1031, 2020 WL 6375575, at *10
(D. Del. Oct. 30, 2020) (Markman Op.); see also, e.g.,
J.A. 2930 (NexStep arguing that “VoIP stands for Voice
Over Internet Protocol,” which is “a well-known protocol to”
a skilled artisan.). Given this agreement, the district court
turned to extrinsic “[e]vidence of the industry standard
definition for VoIP.” Markman Op., 2020 WL 6375575, at
*10.
Based on the extrinsic evidence, the district court
construed “VoIP” as “protocols and data formats for
transmitting voice conversations over a packet-switched
network, such as the Internet.” Id. (emphasis added). The
district court rejected NexStep’s broader construction,
which covered any “audio data,” and instead relied on
several technical dictionaries that defined VoIP as
2 The district court referred claim construction
proceedings to a magistrate judge, who issued a report and
recommendation addressing the meaning of VoIP. NexStep,
Inc. v. Comcast Cable Commc’ns, LLC, No. 19-cv-1031,
2020 WL 6375575, at *10–11 (D. Del. Oct. 30, 2020). The
district court adopted the report and recommendation in
full with respect to the term VoIP. See NexStep, Inc. v.
Comcast Cable Commc’ns, LLC, No. 19-cv-1031, 2021 WL
3489983, at *1 (D. Del. Aug. 9, 2021). We refer to the
opinions by the magistrate judge and district court judge
collectively as the district court’s opinion.
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 7
specifically transmitting “voice conversations” in a manner
analogous to conventional telephone calls. Id. at *10–11.
Comcast moved for summary judgment of non-
infringement because its accused Voice Remote products
did not infringe the VoIP limitation under the district
court’s construction. In considering the motion, the district
court noted that the factual operation of Comcast’s accused
Voice Remotes was not disputed. NexStep, Inc. v. Comcast
Cable Commc’ns, LLC, No. 19-cv-1031, 2022 WL 911252, at
*2 (D. Del. Mar. 29, 2022) (Summary Judgment Op.). The
parties agreed that each Voice Remote captures voice
commands from a user (for example, “turn the television to
channel 5”) and that the set-top box sends the captured
audio to Comcast’s servers, using a type of protocol called
HTTP.
Importantly, in its summary judgment briefing to the
district court, NexStep did “not suggest that [Comcast’s]
accused products are capable of two-way voice
conversations.” NexStep, Inc. v. Comcast Cable Commc’ns,
LLC, No. 19-cv-1031, 2021 WL 4077778, at *9 (D. Del. Aug.
20, 2021) (Summary Judgment R. & R.). NexStep
identified no evidence that the accused products used a
protocol configured to send two-way audio
communications. Instead, NexStep argued that the VoIP
limitation could be met by a protocol capable of only one-
way audio transmission, contrary to Comcast’s assertion
that VoIP, as construed by the district court, required
capability for two-way voice conversations. See, e.g., J.A.
8475–76 (NexStep’s summary judgment briefing).
The district court agreed with Comcast’s view. See
Summary Judgment Op., 2022 WL 911252, at *2. The
court again rejected NexStep’s attempt to broaden the
meaning of VoIP to cover a protocol for any transmission of
audio data, instead agreeing that “voice conversations”
required capability for two-way communication. Id.
Because NexStep’s opposition to summary judgment
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 8
hinged on its claim construction arguments, the district
court found no genuine dispute of material fact.
Accordingly, it granted summary judgment of non-
infringement of the asserted claims of the ’802 patent.
C.
“We review a district court’s grant of summary
judgment according to the law of the regional circuit.”
Amgen Inc. v. Sandoz Inc., 923 F.3d 1023, 1027 (Fed. Cir.
2019). Here, we apply the law of the Third Circuit, which
reviews “a district court’s grant of summary judgment de
novo, applying the same standard the district court
applied.” Viera v. Life Ins. Co. of N. Am., 642 F.3d 407, 413
(3d Cir. 2011). We apply Federal Circuit law to substantive
questions of patent law, including claim construction.
Powell v. Home Depot U.S.A., Inc., 663 F.3d 1221, 1228
(Fed. Cir. 2011).
“Claim construction requires determining how a skilled
artisan would understand a claim term ‘in the context of
the entire patent, including the specification.’” Grace
Instrument Indus., LLC v. Chandler Instruments Co., 57
F.4th 1001, 1008 (Fed. Cir. 2023) (quoting Phillips v. AWH
Corp., 415 F.3d 1303, 1313 (Fed. Cir. 2005) (en banc)). “We
review claim construction based on intrinsic evidence de
novo and review any findings of fact regarding extrinsic
evidence for clear error.” Id.; see also Teva Pharms. USA,
Inc. v. Sandoz, Inc., 574 U.S. 318, 332–33 (2015); Fed. R.
Civ. P. 52(a)(6). Under the clear-error standard, we defer
to the district court’s findings “in the absence of a definite
and firm conviction that a mistake has been made.” Par
Pharm., Inc. v. Eagle Pharms., Inc., 44 F.4th 1379, 1383
(Fed. Cir. 2022) (citation omitted).
In general, the specification is the “single best guide to
the meaning of a disputed term” and “is, thus, the primary
basis for construing the claims.” Grace Instrument, 57
F.4th at 1008 (citations omitted). But extrinsic evidence
takes on particular importance when construing a term
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 9
that skilled artisans recognized as a term of art at the
relevant time. Phillips permits courts to consider extrinsic
evidence to determine whether a claim term was, in fact,
recognized as a term of art. 415 F.3d at 1318 (indicating
that courts may rely on extrinsic evidence “to establish that
a particular term in the patent or the prior art has a
particular meaning in the pertinent field”). If the court
finds that the relevant skilled artisans understood the
phrase as a term of art, then the court may make factual
findings as to what meaning a skilled artisan would ascribe
to that term. Teva, 574 U.S. at 331 (explaining that
sometimes “the district court will need to look beyond the
patent’s intrinsic evidence and to consult extrinsic evidence
in order to understand . . . the meaning of a term in the
relevant art during the relevant time period”). The court
must focus its analysis on the term’s meaning “as of the
effective filing date of the patent application.” Phillips, 415
F.3d at 1313, 1318; Teva, 574 U.S. at 331.
D.
NexStep fails to show that the district court clearly
erred by construing VoIP to require capability for two-way
voice communications.
The district court’s construction is supported by its
reliance on two technical dictionaries, which defined VoIP
to require voice conversations. The first dictionary—
Newton’s Telecom Dictionary—defined VoIP as “[t]he
technology used to transmit voice conversations over a data
network.” Markman Op., 2020 WL 6375575, at *10
(quoting J.A. 2998). Similarly, the Dictionary of Computer
and Internet Terms defined VoIP as “the transmission of
voice telephone conversations through the Internet or
through IP networks.” Id. (quoting J.A. 3003).
These definitions are consistent with the district
court’s construction and support a two-way voice
communication requirement. Both dictionaries liken VoIP
to other forms of telephony, such as cellular calls and
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landline calls, which are two-way voice communication
systems. The association between VoIP and other forms of
telephony reasonably supports the inference that VoIP is
also a two-way voice communication system. Given this
evidence, the district court had a sufficient basis for its
construction.
NexStep’s principal rebuttal is that Newton’s
dictionary supports NexStep’s view by indicating that VoIP
includes “voice emails.” NexStep reasons that if VoIP
includes voice emails, a one-way communication, then the
district court clearly erred in limiting VoIP to two-way
communications.
The district court considered and rejected this
argument because Newton’s dictionary “confirms that VoIP
protocols must be capable of facilitating ‘phone calls’ and
may include additional new services such as voice emails.”
Summary Judgment Op., 2022 WL 911252, at *2 (emphasis
added) (citation omitted). In other words, the district court
read Newton’s dictionary as discussing “voice emails” as a
supplemental service, and the district court did not clearly
err in its reading of the dictionary definition.
Similarly, the district court did not clearly err in
rejecting the testimony of NexStep’s expert, Dr. Selker.
The sole source cited by Dr. Selker undermined his claim
that VoIP is broad enough to cover all audio data
transmission by explaining that “VoIP is a category of
technologies that route real-time voice conversations over
the internet.” Markman Op., 2020 WL 6375575, at *10–11.
That Dr. Selker’s underlying evidence contradicted his
opinion testimony provided ample basis for the district
court to reject the testimony. Accordingly, the district court
did not clearly err in this respect either.
E.
For the first time on appeal, NexStep asserts the ’802
patent adopted an unconventional definition of VoIP that
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 11
departs from its established meaning. Appellant’s Br. 56
(arguing that the “scope VoIP was given in NexStep’s
patents” is broad enough to cover one-way audio
transmission).
NexStep never made that argument below, and instead
affirmatively asserted the opposite view by contending that
the established meaning of VoIP controlled the
interpretation of the term. See supra Section II.B. The
district court expressly relied on NexStep’s representations
in construing VoIP in accord with its industry standard
meaning at the relevant time. Markman Op., 2020 WL
6375575, at *10. Based on these representations, NexStep
forfeited any argument that the ’802 patent redefined VoIP
to differ from its industry standard meaning.
Nevertheless, we note that NexStep’s contentions
about the intrinsic evidence are plainly incorrect. The
written description repeatedly associates VoIP with
telephony services that require capability for two-way voice
communications. For example, the written description
describes a list of hardware and software features that are
“within the scope of this disclosure for providing services
described” and lists as the first entry of such services,
“Communication, including Phone (LL/Cell/IP).” ’802
patent col. 20 ll. 11–13, 39–41.3 This reference to “[p]hone”
services, followed by three subtypes of phone service
(landline, cellular, and VoIP), suggests that the written
3 The specification makes clear that when “IP” is
referred to in conjunction with “landline” and “cellular”
services, it means VoIP. See, e.g., ’802 patent col. 18 l. 65 –
col. 19 l. 2 (explaining that the master console may connect
to a landline-based “telephone system,” “to a cellular or
similar telephone system[,] or to a voice over IP (VoIP)
system”); id. col. 20 ll. 11–13, 20 (listing “Voice
(Landline/cell/IP)” as a “feature[] . . . within the scope of
this disclosure”).
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 12
description understood VoIP as a type of phone service akin
to those that support two-way voice conversations. And
when describing how the claimed master device can
communicate externally, the ’802 patent explains that it
may connect to (1) a conventional landline telephone
system, (2) “a cellular or similar telephone system,” or
(3) “a voice over IP (VoIP) system.” Id. col. 18 l. 65 – col. 19
l. 2. These portions of the written description are
consistent with the district court’s findings about the
established meaning of VoIP. NexStep has identified
nothing in the written description to the contrary.
Indeed, the sole portion of the written description cited
by NexStep is inapposite. NexStep argues that the written
description equates VoIP with one-way communication
tools, such as “dictation” or “note taking.” Appellant’s Br.
56. But the written description simply does not equate
VoIP with those tools. The relevant portion provides:
In a fifth embodiment, the remote is emphasized.
One aspect of the remote is to provide a complete
I/O platform in the palm of the user’s hand.
Features adaptable to VoIP and/or video phone
operation, such as a microphone, can be used for
other purposes, such as dictation, note taking, voice
messaging, listening to music or remote viewing
video.
’802 patent col. 3 ll. 58–63 (emphases added). As the
district court correctly observed, this passage merely notes
that hardware components used in VoIP conversations—
“such as a microphone”—can also be used for “other
purposes” (such as dictation). Id.; Markman Op., 2020 WL
6375575, at *11. Nothing in this paragraph redefines VoIP
to encompass protocols not capable of supporting two-way
communication.
NexStep also presses an argument based on the
doctrine of claim differentiation. Specifically, NexStep
asserts that the inclusion of an audio-output limitation in
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unasserted, independent claim 4 of the ’802 patent implies
that VoIP, as used in claims 1 and 7, must not require
capability for two-way communication. See Appellant’s Br.
57. However, “we have been cautious in assessing the force
of claim differentiation in particular
settings, . . . discounting it where it is invoked based on
independent claims.” Atlas IP, LLC v. Medtronic, Inc., 809
F.3d 599, 607 (Fed. Cir. 2015). We are unconvinced that
construing VoIP to require capability for two-way
communication renders superfluous claim 4’s requirement
for an audio output, particularly because claim 4 does not
even recite a VoIP limitation. See also Andersen Corp. v.
Fiber Composites, LLC, 474 F.3d 1361, 1370 (Fed. Cir.
2007) (declining to apply claim differentiation where “there
are numerous other differences varying the scope of the
claimed subject matter”).4
F.
Finally, NexStep argues that even if we agree with the
district court’s construction of VoIP, we should remand for
a trial on infringement because NexStep showed genuine
disputes of material fact even under the court’s clarified
construction.
NexStep forfeited this argument by failing to present it
to the district court. “We have regularly stated and applied
the important principle that a position not presented in the
4 NexStep’s reply brief raises additional claim
differentiation arguments, including as to other
independent claims of the ’802 patent and claims of other
patents. Arguments not raised in an opening brief are
forfeited. Stinson v. McDonough, 92 F.4th 1355, 1362 n.5
(Fed. Cir. 2024). In any event, for the same reasons, we
remain unpersuaded that affording VoIP its industry
standard meaning would render superfluous the audio
output limitations of these claims.
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tribunal under review will not be considered on appeal in
the absence of exceptional circumstances.” In re Google
Tech. Holdings LLC, 980 F.3d 858, 863 (Fed. Cir. 2020).
Before the district court, NexStep opposed summary
judgment by arguing that one-way audio transmissions
satisfied the district court’s construction of VoIP. See supra
Section II.B. As a result, the magistrate judge explained
her understanding that NexStep “does not suggest that
Defendant’s accused products are capable of two-way voice
conversations.” Summary Judgment R. & R., 2021 WL
4077778, at *9. And the district court judge characterized
NexStep’s summary judgment briefing as instead
“advanc[ing] several claim construction arguments” about
the meaning of VoIP and the best understanding of the
court’s Markman order. Summary Judgment Op., 2022 WL
911252, at *2.
NexStep’s briefing to this court gives us no basis to
disagree with the district court’s characterization of the
arguments before it. NexStep failed to identify anything in
the record asserting that Comcast’s accused products use a
protocol configured to send two-way voice conversations.
Indeed, NexStep’s reply brief points to evidence NexStep
cited below that was expressly premised on the assertion
that one-way communications are sufficient to infringe.
See, e.g., Appellant’s Reply Br. 33 (citing J.A. 9062).
Accordingly, NexStep forfeited this argument.
For the reasons explained above, we affirm the district
court’s construction of VoIP and affirm its grant of
summary judgment of non-infringement of the asserted
claims of the ’802 patent.
III.
The second principal issue on appeal relates to the
district court’s disposition of the ’009 patent. For the
reasons that follow, we agree that the district court
correctly granted Comcast’s motion for judgment as a
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 15
matter of law of non-infringement under the doctrine of
equivalents.
A.
The ’009 patent is directed to a “concierge device” that
offers a streamlined approach for initiating technical
customer support. ’009 patent Abstract. With the advent
of the “Internet of things,” the ’009 patent observed that
customers were increasingly swapping out traditional
home appliances in favor of smart devices. Id. col. 2 ll. 14–
27. This changeover of devices created an “opportunity for
innovation” to enhance the customer service experience by
allowing consumers to more easily and efficiently control
and support the interconnection of consumer devices with
services outside of the home. Id. col. 2 ll. 28–41.
Specifically, the ’009 patent discusses a concierge device
that initiates technical support in response to only “a single
action” of the user. Id. Abstract. The parties agree that the
point of novelty for the claimed invention is initiating a
customer service support session through just a “single
action,” saving the user time and the hassle of all the steps
inherent in calling a support center and having to provide
the model, serial number, or other information to identify
what products are malfunctioning.
Claim 1 is illustrative for purposes of the issues on
appeal. It provides:
1. A method of initiating a support session for a
consumer device using a concierge device, the
method including:
associating the concierge device with a selected
consumer device;
responsive to a single action performed by a user,
the concierge device communicating with a home
gateway, including
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 16
causing the home gateway to buffer
consumer device identification information
for the selected consumer device and
determine a support center for a support
session; and
causing the home gateway to initiate the
support session for the consumer device
and to forward automatically the consumer
device identification information during
the support session, thereby allowing the
support session either
to bypass an automated attendant
or interactive voice recognition
system or
to initiate an automated support
protocol.
’009 patent claim 1 (emphasis added).
According to claim 1, when a troubleshooting issue
arises, all the claimed steps must occur “responsive to a
single action performed by a user.” See, e.g., ’009 patent
claim 1 (emphasis added). That “single action” could be,
for example, “a single press of a button,” a “shake of the
device,” or a “spoken response.” Id. col. 4 l. 65 – col. 5 l. 3;
see also id. col. 11 ll. 18–21 (describing a “dedicated button”
used to initiate a support call).
Following the user’s “single action,” the concierge
device of claim 1 responds by taking four specific
“troubleshooting” steps to initiate a personalized customer
support session. First, the concierge device conveys
“consumer device identification information” for the
product at issue. Second, the concierge device identifies an
appropriate technical team to support the relevant product
by “determin[ing] a support center” that can offer a
“support session” for the user’s device. Third, the concierge
device causes the home gateway to initiate the support
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 17
session for the consumer device. Fourth, the concierge
device causes the home gateway to automatically forward
the consumer device information during the support
session.
As a result, the ’009 patent discloses a user-friendly,
streamlined system that bypasses the need for a user to
undertake a series of actions before a support session can
begin and instead “allows the user in a single action to
initiate a support call without requiring the user” to engage
in any additional steps before receiving technical support.
Id. col. 5 ll. 20–25 (emphasis added). The claimed
invention is thus directed to minimizing a user’s
interaction with a device to just one action to initiate a
support session.
B.
Before the district court, NexStep asserted that three
different tools in Comcast’s mobile smartphone application
(My Account App) infringed claims 1, 16, and 22 of the ’009
patent. The first tool is the “XfinityAssistant,” an
interactive chatbot that can help customers with services
related to the customer’s account, billing, privacy, and
troubleshooting. The second tool is a “Troubleshooting
Card,” which triggers a multi-step process for
troubleshooting a given device associated with the
customer’s Comcast account. And the third tool is the
“Diagnostic Check,” which allows a user to investigate
whether a particular device has detectable issues.
Initiating each of these three tools requires a user to press
a series of buttons on the smartphone’s display.5
5 The parties dispute on appeal how many individual
steps are involved for each of the accused tools. We note
that Dr. Selker’s doctrine-of-equivalents testimony
assumed the tools require “several button presses.”
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At trial, the parties’ dispute focused heavily on the
“single action” limitation. Comcast argued that the
multiple actions—the several user button presses—
required as a predicate to using any of the three
troubleshooting tools meant that the My Account App did
not infringe. NexStep focused its infringement theory on
the view that a series of steps, when taken together, can be
appropriately described as a single action. See, e.g.,
J.A. 460 at 443:24–445:4 (arguing that “multiple steps
might be contained in a single action”). Thus, NexStep
argued, even if using each of the three accused tools
involved multiple steps, those steps should be understood
as a single action.
The jury returned a verdict of no literal infringement
(thus necessarily rejecting NexStep’s view that the series
of user steps needed for each of the accused tools amounted
to “a single action”) but found infringement under the
doctrine of equivalents. JMOL Decision, 2022 WL
1503922, at *1. Following trial, both parties moved for
judgment as a matter of law: NexStep for literal
infringement and Comcast for non-infringement under the
doctrine of equivalents. The district court denied
NexStep’s motion, and it granted Comcast’s motion because
NexStep failed to offer the particularized testimony and
linking argument required by our precedent for a doctrine
of equivalents case.
NexStep appeals. It challenges only the district court’s
decision to set aside the infringement verdict under the
doctrine of equivalents; NexStep does not challenge the
denial of judgment as a matter of law of literal
infringement.
J.A. 445 at 383:25–384:10. The actual number of button
presses is not material to our analysis for the reasons given
below.
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C.
1.
Judgment as a matter of law is appropriate if “the
court finds that a reasonable jury would not have a legally
sufficient evidentiary basis to find for the party on that
issue.” Fed. R. Civ. P. 50(a)(1). The Third Circuit reviews
de novo a district court’s grant of judgment as a matter of
law, viewing the record evidence in the light most favorable
to and drawing all reasonable inferences in favor of the
verdict winner. Pitts v. Delaware, 646 F.3d 151, 155 (3d Cir.
2011).
2.
“Patent infringement is principally determined by
examining whether the accused subject matter falls within
the scope of the claims” as literally written. Eli Lilly & Co.
v. Hospira, Inc., 933 F.3d 1320, 1330 (Fed. Cir. 2019). But
“[t]he doctrine of equivalents provides a limited exception
to the principle that claim meaning defines the scope of the
exclusivity right in our patent system.” VLSI Tech. LLC v.
Intel Corp., 87 F.4th 1332, 1341 (Fed. Cir. 2023). “The
limits reflect a familiar balance among the importance of
preserving the public’s ability to rely on claims’ meaning to
define patent scope, the ability of patentees to protect their
inventions through their claim drafting, and (yet) the
occasional need to recognize some non-literal scope of
protection to avoid undermining the exclusivity rights
authorized by Congress to incentivize certain innovations.”
Id. at 1342. A finding of infringement under the doctrine
of equivalents is “exceptional,” Honeywell International,
Inc. v. Hamilton Sundstrand Corp., 523 F.3d 1304, 1313
(Fed. Cir. 2008), and “[w]e have emphasized . . . that the
doctrine of equivalents is the exception, however, not the
rule,” Eli Lilly, 933 F.3d at 1330 (internal quotation marks
omitted).
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Under the doctrine of equivalents, “a product or process
that does not literally infringe upon the express terms of a
patent claim may nonetheless be found to infringe if there
is ‘equivalence’ between the elements of the accused
product or process and the claimed elements of the
patented invention.” Warner-Jenkinson Co. v. Hilton
Davis Chem. Co., 520 U.S. 17, 21 (1997) (citing Graver
Tank & Mfg. Co. v. Linde Air Prods. Co., 339 U.S. 605, 609
(1950)). Typically, patentees seek to prove infringement
under the doctrine of equivalents in one of two ways.
Mylan Institutional LLC v. Aurobindo Pharma Ltd., 857
F.3d 858, 866 (Fed. Cir. 2017). One way, often referred to
as the function-way-result test, asks “whether the accused
product performs ‘substantially the same function in
substantially the same way to obtain the same result.’” Id.
(quoting Graver Tank, 339 U.S. at 608). And the other way
asks whether “differences between the claimed invention
and the accused device or process are ‘insubstantial.’” Tex.
Instruments Inc. v. Cypress Semiconductor Corp., 90 F.3d
1558, 1563–64 (Fed. Cir. 1996). “Different linguistic
frameworks may be more suitable to different cases,
depending on their particular facts,” but these
formulations all aim to investigate the same “essential
inquiry.” Warner-Jenkinson, 520 U.S. at 40.
Regardless of how the test is phrased, courts must
employ “special vigilance” to avoid overbroad applications
of the doctrine of equivalents. Id. “There can be no denying
that the doctrine of equivalents, when applied broadly,
conflicts with the definitional and public-notice functions
of the statutory claiming requirement.” Id. at 29. We have
accordingly imposed “specific evidentiary requirements
necessary to prove infringement under the doctrine of
equivalents.” Tex. Instruments, 90 F.3d at 1566.
First, proof under the doctrine of equivalents must be
on a limitation-by-limitation basis: “[T]he doctrine of
equivalents must be applied to individual elements of the
claim, not to the invention as a whole.” Warner-Jenkinson,
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520 U.S. at 29. This requirement means that equivalency
is determined by comparing “the elements of the accused
product or process and the claimed elements of the
patented invention.” Id. at 21 (citing Graver Tank, 339
U.S. at 609); see also VLSI, 87 F.4th at 1344–45.
Second, “both the Supreme Court and this court have
made clear that the evidence of equivalents must be from
the perspective of someone skilled in the art, for example
through testimony of experts or others versed in the
technology; by documents, including texts and treatises;
and, of course, by the disclosures of the prior art.” AquaTex
Indus., Inc. v. Techniche Sols., 479 F.3d 1320, 1329 (Fed.
Cir. 2007) (cleaned up). “[W]hen the patent holder relies
on the doctrine of equivalents,” we “require that evidence
be presented to the jury or other fact-finder through the
particularized testimony of a person of ordinary skill in the
art, typically a qualified expert.” Id.
Third, and most relevant to this appeal, “we have long
demanded specificity and completeness of proof as crucial
to enforcing the limits on the doctrine: The patentee must
provide particularized testimony and linking argument as
to the insubstantiality of the differences between the
claimed invention and the accused device.” VLSI, 87 F.4th
at 1343 (internal quotation marks and citations omitted).
“Generalized testimony as to the overall similarity between
the claims and the accused infringer’s product or process
will not suffice.” Tex. Instruments, 90 F.3d at 1567.
Rather, the patentee must provide a “meaningful
explanation of why” the element or elements from the
accused product or process are equivalent to the claimed
limitation. VLSI, 87 F.4th at 1344; see also Malta v.
Schulmerich Carillons, Inc., 952 F.2d 1320, 1327 n.5 (Fed.
Cir. 1991) (Our precedent “at least requires the evidence to
establish what the function, way, and result of both the
claimed device and the accused device are, and why those
functions, ways, and results are substantially the same.”).
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“Our court set forth these evidentiary requirements in
those earlier cases because, although the standard for
infringement under the doctrine of equivalents is simple to
articulate, it is conceptually difficult to apply.” Tex.
Instruments, 90 F.3d at 1566–67. “These evidentiary
requirements assure that the fact-finder does not, under
the guise of applying the doctrine of equivalents, erase a
plethora of meaningful structural and functional
limitations of the claim on which the public is entitled to
rely in avoiding infringement.” Id. at 1567 (internal
quotation marks and citation omitted). Plus, “without
these requirements, the fact-finder has no analytical
framework for making its decision and is put to sea without
guiding charts when called upon to determine
infringement under the doctrine,” and “we, as the
reviewing court, would lack the assurance that the jury
was fully presented with a basis for applying the doctrine
of equivalents.” Id. (cleaned up).
Though “we do not doubt the ability of a jury to decide
the factual issue of equivalence, to enable the jury to use
its ability,” the patentee’s case “must be presented in the
form of particularized testimony and linking argument.”
Lear Siegler, Inc. v. Sealy Mattress Co. of Mich., 873 F.2d
1422, 1426 (Fed. Cir. 1989). These evidentiary
requirements therefore serve to “ensure that a jury is
provided with the proper evidentiary foundation from
which it may permissibly conclude that a claim limitation
has been met by an equivalent.” Comark Commc’ns, Inc. v.
Harris Corp., 156 F.3d 1182, 1188 (Fed. Cir. 1998).
So though “[a] finding of equivalence is a determination
of fact,” Graver Tank, 339 U.S. at 609, “the various legal
limitations on the application of the doctrine of equivalents
are to be determined by the court, either on a pretrial
motion for partial summary judgment or on a motion for
judgment as a matter of law at the close of the evidence and
after the jury verdict,” Warner-Jenkinson, 520 U.S. at 39
n.8. Accordingly, we have consistently rejected doctrine of
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 23
equivalents theories as a matter of law when a patentee’s
case lacks particularized testimony and linking argument.
See, e.g., VLSI, 87 F.4th at 1344–45 (reversing jury
verdict); Tex. Instruments, 90 F.3d at 1567–68 (affirming
grant of judgment as a matter of law); Lear Siegler, 873
F.2d at 1423, 1425–27 (reversing jury verdict); Malta, 952
F.2d at 1321, 1327 (affirming grant of judgment as a
matter of law); AquaTex, 479 F.3d at 1323 (“[W]e affirm the
grant of summary judgment because [patentee] did not
satisfy its burden to present particularized evidence of
equivalents in opposition to the motion for summary
judgment.”); Gemalto S.A. v. HTC Corp., 754 F.3d 1364,
1374–75 (Fed. Cir. 2014) (affirming grant of summary
judgment).
3.
With these principles in mind, we turn to the evidence
that NexStep adduced to support a finding of infringement
under the doctrine of equivalents. NexStep points us to the
following testimony from Dr. Selker, who relied on the
function-way-result test to attempt to prove that the
“single action” limitation is met under the doctrine of
equivalents:
Q. In terms of the elements of the ’009 patent, can
you explain why the – I understand that you
believe that a single action is met literally, but can
you explain why at the very least the single action
element is met by the doctrine of equivalents? And
the –
A. When you – when you go to debug your – to
diagnose your device, you’re going through a single
action. It might be that there’s several button
presses along the way, but I say that’s the same
function. And that it’s going to have the same
purpose which is what I was talking about, I hope.
I don’t know if I’m –
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 24
Q. No, you’re doing fine, Doctor. Keep going.
A. I was confused by that.
Q. It’s the same function – I’ll just help you out
here. So it has the same function and it’s a legal
doctrine and so we have to go through it. Okay?
Can you explain to the jury why it’s done in
substantially the same way?
A. Well, it’s done in the same way in that the stuff
is all kept up in the cloud for the purpose of doing
this and it’s going to go and diagnose it using the
home gateway and it’s going to solve my problem
without me having to go through and put in my
model numbers and all of that stuff. So it’s really
literally using – using this Concierge as more of a
– somebody to give authorization than to do the
actual function. I’m not down there in the machine
room, you know, putting instructions into a
computer to make it do each of these things.
Q. And can you explain why the single action
achieves substantially the same result?
A. Yeah, the result is that this thing is going to be
restarted, refreshed, whatever is going to have to
happen with it without me having to tangle with
understanding all of the issues of being an IT
professional or whatever it takes to get this thing
up. And so it’s going to come with a result of my
modem working, you know.
J.A. 445 at 383:25–385:9. This is the only testimony that
we are aware of in which NexStep asserted infringement
specifically under the doctrine of equivalents.
NexStep “had to prove—with particularized testimony
and linking argument—that the elements of the [accused]
arrangement were substantially the same as the elements
of the claimed arrangement.” VLSI, 87 F.4th at 1344–45.
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Though “infringement under the doctrine requires ‘only’
substantial identity, substantial identity must be proven
with regard to all three elements of the” function-way-
result test. Lear Siegler, 873 F.2d at 1425. Meeting this
evidentiary burden “at least requires the evidence to
establish what the function, way, and result of both the
claimed device and the accused device are, and why those
functions, ways, and results are substantially the same.”
Malta, 952 F.2d at 1327 n.5. NexStep failed to meet its
evidentiary burden for several reasons.
First, Dr. Selker’s testimony never identified a
particular element or elements in the My Account App as
being equivalent to the “single action” limitation. Because
the test is to determine whether “the elements of the
[accused] arrangement [are] substantially the same as the
elements of the claimed arrangement,” a patentee must
identify what element or elements in the accused device are
equivalent to the claimed limitation. VLSI, 87 F.4th at
1344–45; see also Malta, 952 F.2d at 1327 n.5 (Our
precedent “at least requires the evidence to establish what
the function, way, and result of both the claimed device and
the accused device are.”). Dr. Selker’s generalized
reference to “several button presses” fails to identify what
specific elements in the My Account App are allegedly
equivalent to the clamed “single action” limitation. This
lack of specificity is particularly problematic because
Dr. Selker identified three separate literal infringement
theories (XfinityAssistant, Troubleshooting Card, and
Diagnostic Check), each with its own distinct series of
button presses. Yet Dr. Selker’s passing reference to
“several button presses” did not guide the jury to focus on
what theory or what button presses are allegedly
equivalent. In short, Dr. Selker’s testimony simply does
not include a particularized identification of what elements
in the accused device are equivalent to the claimed
limitation.
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 26
By itself, the failure to explicitly identify the alleged
equivalent is fatal to NexStep’s doctrine of equivalents
theory. If a jury is not told what components are
equivalent, it necessarily cannot find those components to
be equivalent to a claim limitation. But Dr. Selker’s
testimony was also deficient because it failed to provide a
“meaningful explanation of why” the element or elements
from the accused product or process are equivalent to the
claimed limitation for each part of the function-way-result
test. VLSI, 87 F.4th at 1344 (emphasis added).
As the district court recognized and as is apparent from
the claim language, the function of the “single action”
limitation is to cause the home gateway to perform the four
troubleshooting steps. JMOL Decision, 2022 WL 1503922,
at *6. Indeed, the parties agree that the whole point of the
claimed invention is to save a user the time and the hassle
of contacting and communicating with customer service by
initiating a support session through a single action, such
as the click of a button. Based on Dr. Selker’s testimony
above, it is not clear if he identified a function, and to the
extent he identified the function as “to diagnose your
device,” it is not clear that this function aligns with the
claimed function of the “single action” limitation. J.A. 445
at 384:5–10. Putting aside these potential errors,
Dr. Selker testified that “several button presses along the
way” provides the same function because he “say[s] that’s
the same function.” Id.
We agree with the district court that this conclusory
and circular “because I said so” testimony is insufficient.
Dr. Selker failed to provide what our precedent requires:
“particularized testimony explaining why the
function . . . [was] the same.” Tex. Instruments, 90 F.3d at
1568 (citation omitted). An expert’s “offhand and
conclusory statements” that the purported equivalent
“function[s] like” the claim limitation is insufficient.
Malta, 952 F.2d at 1327. NexStep therefore failed to
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 27
provide a sufficient evidentiary showing under the function
prong of the function-way-result test.
As for the way prong, Dr. Selker’s testimony is difficult
to parse:
Well, it’s done in the same way in that the stuff is
all kept up in the cloud for the purpose of doing this
and it’s going to go and diagnose it using the home
gateway and it’s going to solve my problem without
me having to go through and put in my model
numbers and all of that stuff. So it’s really literally
using – using this Concierge as more of a –
somebody to give authorization than to do the
actual function. I’m not down there in the machine
room, you know, putting instructions into a
computer to make it do each of these things.
J.A. 445 at 384:17–385:1. The district court aptly
described this testimony as “word salad” and noted that, to
the extent it communicated anything to the jury, this
testimony “did not provide particularized testimony or a
linking argument for why several button presses perform
the claimed method in the same way as the claimed single
action.” JMOL Decision, 2022 WL 1503922, at *7.
We agree with the district court that this testimony is
insufficient because of its “failure to articulate how [the]
accused process operates in substantially the same way.”
Akzo Nobel Coatings, Inc. v. Dow Chem. Co., 811 F.3d 1334,
1343 (Fed. Cir. 2016). Once again, it is not clear that
Dr. Selker identified the “way” that the accused product or
the claim limitation operates. To the extent that he
adequately identified the way for either, he fails to explain
how the “several button presses” for any of the three My
Account App tools (which the jury necessarily found to be
multiple actions as opposed to a single action) should be
understood to be performing the single action limitation in
substantially the same way. In other words, Dr. Selker
failed to provide “meaningful explanation of why” the
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 28
“several button presses” operate in substantially the same
way as the “single action” limitation. VLSI, 87 F.4th at
1344.
Finally, for the result prong, Dr. Selker testified that:
[T]he result is that this thing is going to be
restarted, refreshed, whatever is going to have to
happen with it without me having to tangle with
understanding all of the issues of being an IT
professional or whatever it takes to get this thing
up. And so it’s going to come with a result of my
modem working, you know.
J.A. 445 at 385:4–9. The district court determined that
this testimony was “untethered from the claim language”
and “amounts to little more than ‘generalized testimony as
to the overall similarity between the claims and the
accused infringer’s product.’” JMOL Decision, 2022 WL
1503922, at *7 (quoting Tex. Instruments, 90 F.3d at 1567).
We agree with the district court on both points.
The claim language provides that the result of the
“single action” limitation is the home gateway performs the
four troubleshooting steps. Here, Dr. Selker merely
testified that something is going to happen so that the
modem works. That result is not in accord with the specific
result required by the claim language.
While our precedent doesn’t necessarily require an
expert’s testimony to be an ipsis verbis recitation of the
claim, Dr. Selker’s identified result is also too generalized,
unclear, and unconnected to the claimed invention.
Though the result of the claimed invention as a whole is to
initiate a support session, “[g]eneralized testimony as to
the overall similarity between the claims and the accused
infringer’s product or process [does] not suffice.” Tex.
Instruments, 90 F.3d at 1567.
Overall, Dr. Selker’s testimony is similar to the
testimony we found inadequate in Texas Instruments. In
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 29
that case, one of the patentee’s experts provided only
“generalized testimony as to [the] overall similarity” of the
claimed and accused processes. 90 F.3d at 1567–68. The
patentee’s other expert witness merely “testified, in
conclusive fashion, that the accused processes . . . met the
Graver Tank function, way, result test” but did not explain
“whether or how the way the accused product operates was
similar to the patent claim,” nor provide “any
particularized testimony explaining why the function and
result were the same.” Id. at 1568 (cleaned up). We
explained that neither witness’s testimony was “sufficient
to support a finding of infringement under the doctrine of
equivalents.” Id. Here, Dr. Selker’s testimony—including
his failure to identify what particular elements are
allegedly equivalent; failure to explain why the function,
way, and result are substantially similar between the
accused elements and the claim limitation; and resorting
to comparing the overall similarities of the accused device
and the claimed invention—fares no better than the
testimony in Texas Instruments.
For all these reasons, Dr. Selker’s testimony failed to
provide the requisite particularized testimony and linking
argument. NexStep’s infringement theory under the
doctrine of equivalents was therefore legally insufficient
because it failed to comply with “the specific evidentiary
requirements necessary to prove infringement under the
doctrine” of equivalents. Tex. Instruments, 90 F.3d at 1566.
Accordingly, the district court properly granted, and indeed
was “obliged to grant,” judgment as a matter of law.
Warner-Jenkinson Co. v. Hilton Davis Chem. Co., 520 U.S.
17, 39 n.8 (1997).
D.
NexStep raises several arguments in favor of
nonetheless reversing the district court’s order. We address
each in turn, and none is persuasive.
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 30
1.
NexStep argues that it offered a sufficient basis for the
jury to find infringement under the “insubstantial
differences” formulation of the doctrine of equivalents. We
disagree.
For starters, NexStep did not present an independent
“insubstantial differences” theory at trial. Dr. Selker
phrased his opinion and substantive analysis under the
function-way-result test. See J.A. 445 at 383:25–385:15.
He also agreed that his opinion was that “the single action
limitation is satisfied under the doctrine of equivalents
because it performs substantially the same function in
substantially the same way to achieve substantially the
same result.” Id. at 385:10–15. And the phrase
“insubstantial differences” (or any similar phrase) does not
appear in Dr. Selker’s testimony. These facts support a
conclusion that Dr. Selker did not provide an insubstantial
differences theory that was not dependent on his function-
way-result theory.
In any event, the testimony adduced at trial confirms
that Dr. Selker in fact did not provide sufficient evidence
to show (separately from his function-way-result
presentation or, indeed, at all) that certain elements of the
accused devices are insubstantially different from the
single action limitation. NexStep points us to the following
direct examination testimony to support its argument that
Dr. Selker testified that a sequence of screen taps is
insubstantially different from the “single action”
limitation:
Q. In your view, does the – tell us in your view,
what is – does a single action, can it initiate a
troubleshooting process?
A. Yes.
Q. Can you explain why?
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A. Well, a single action like fixing your modem is
something that you embark to do and, you know,
whatever a single action is, let’s say it’s even
pressing a button, you have to see the button, you
have to go think about it, you have to move your
finger to it, you have to go and press it and you have
to see that it’s responded. So whatever a single
action is, whether a single press or other things,
there’s some parts to it. And I call those steps a
single action.
J.A. 434 at 341:25–342:18 (objection omitted). NexStep
also identified the following testimony from Dr. Selker’s
cross examination:
Q. When you gave your equivalents opinion, you
said that your opinion is that the words “single
action” are substantially the same as multiple
single actions; correct?
A. No, not – not all single actions. They’re –
multiple steps might be contained in a single
action. For example, when you throw a baseball,
you pick it up, you orient it, you get it in your palm,
you throw it. There’s several steps to making a
baseball, to throwing a baseball.
* * *
Q. Well, let’s look a little bit further down [in your
expert report] to see if this was, in fact, a typo.
Next sentence, to the extent the action to start the
troubleshooting processing is not literally a single
action, it is at least equivalent to a single action
because a single stream-like action starts the
process to begin troubleshooting including
collecting buffer data from customer service such
as identification data. Do you see that?
A. So this is in my data –
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 32
Q. Dr. Selker –
A. I’ll just trying to explain it.
Q. I understand. And Mr. Hannah will have – he’ll
be able to give you a chance to frame it. My first
question is just, do you see it?
A. I see it.
J.A. 460 at 444:22–445:4, 446:6–20.
In essence, NexStep has identified direct examination
testimony opining that several steps can be a single action
and cross examination testimony opining that multiple
steps may be contained in a single action and that
Dr. Selker sees in his report that a single stream-like
action is at least equivalent to a “single action.”6
As an initial matter, this testimony does not provide an
insubstantial differences theory that makes up for the
deficiency of the function-way-result evidence. The first
two points identified above are literal infringement
testimony: Dr. Selker believes that a single action can
literally be satisfied by several steps. The third point, at
best, states that Dr. Selker has provided a doctrine of
equivalents theory, but nothing suggests that he took an
“insubstantial differences” route independent of his
function-way-result line of reasoning.
But even if we consider the merits of NexStep’s
argument, this testimony still fails to provide
6 To the extent NexStep relies on counsel’s questions,
“[s]tatements of counsel . . . are not evidence.” Galen Med.
Assocs., Inc. v. United States, 369 F.3d 1324, 1339 (Fed. Cir.
2004). And it is black letter law that counsel’s unsworn fact
statements are not evidence and therefore cannot sustain
an infringement finding. Gemtron Corp. v. Saint-Gobain
Corp., 572 F.3d 1371, 1380 (Fed. Cir. 2009).
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particularized testimony and linking argument. Under an
“insubstantial differences” formulation, “a patentee must
still provide particularized testimony and linking
argument as to the ‘insubstantiality of the differences’
between the claimed invention and the accused device or
process” to show infringement under the doctrine of
equivalents. Tex. Instruments, 90 F.3d at 1567. Similar to
his testimony under the function-way-result test,
Dr. Selker’s testimony neither particularly identified what
specific elements of the accused products are allegedly
equivalent to the “single action” limitation nor offered the
required testimony explaining why those elements were
only insubstantially different in light of the claim language
reciting what is being avoided by the “single action.” To
put it simply, Dr. Selker never stated or explained why
several button presses are insubstantially different from a
single action, particularly given that the point of the
“single action” limitation was that a single action saved the
user from undertaking the multiple steps typically
required to initiate a customer support session. Either of
these shortcomings is sufficient to foreclose a verdict of
infringement under the doctrine of equivalents.
2.
NexStep also argues that we should reverse the district
court because NexStep’s literal infringement testimony
coupled with its doctrine of equivalents testimony provides
an adequate basis for finding infringement under the
doctrine of equivalents. NexStep contends that the district
court failed to consider Dr. Selker’s literal infringement
testimony, rendering its conclusion to grant judgment as a
matter of law erroneous. This argument is unpersuasive
for two reasons.
First, the premise of this argument is incorrect. The
district court expressly considered Dr. Selker’s literal
infringement testimony in rendering its decision to grant
judgment as a matter of law. After articulating the law,
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the district court noted that “Dr. Selker’s literal
infringement testimony can support NexStep’s DOE
contentions.” JMOL Decision, 2022 WL 1503922, at *5.
Indeed, the district court found that “Dr. Selker’s literal
infringement testimony somewhat cures the vagueness of
his DOE claim limitation testimony.” Id. But the district
court concluded that “NexStep has simply not met its
burden.” Id. Thus, it is not true that the district court
failed to consider Dr. Selker’s literal infringement
testimony.
Second, this argument also fails on the merits. Though
“[o]ur ‘particularized testimony’ standard does not require
[an expert witness] to re-start his testimony at square one
when transitioning to a doctrine of equivalents analysis,”
Paice LLC v. Toyota Motor Corp., 504 F.3d 1293, 1305 (Fed.
Cir. 2007), “[t]he evidence and argument on the doctrine of
equivalents cannot merely be subsumed in plaintiff’s case
of literal infringement,” Lear Siegler, 873 F.2d at 1425.
That is, even if there “was evidence and argument on literal
infringement[] that may also bear on equivalence,” that
“does not satisfy” the requirements of the doctrine of
equivalents in the absence of particularized testimony and
linking argument. Lear Siegler, 873 F.2d at 1425.
Here, even incorporating the literal infringement
testimony, NexStep fell short of providing particularized
testimony and linking argument. As already discussed,
NexStep failed to produce “evidence to establish what the
function, way, and result of both the claimed device and the
accused device are, and why those functions, ways, and
results are substantially the same.” Malta, 952 F.2d at
1327 n.5; see supra Section III.C. Even if we assume, as
the district court did, that the literal infringement
testimony allowed the jury to understand what “several
button presses” Dr. Selker alleged to be equivalent and if
we assume that the literal infringement testimony
provided the function, way, and result of the “single action”
limitation, Dr. Selker failed to explain why the function,
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way, and result of the accused elements and the claimed
limitation are substantially the same. In short,
Dr. Selker’s conclusory testimony is on par with other
testimony we have rejected as inadequate. See, e.g., VLSI,
87 F.4th at 1343–45; Tex. Instruments, 90 F.3d at 1567–68;
Lear Siegler, 873 F.2d at 1425–26.
3.
NexStep’s final argument is that we should adopt a
novel exception to the requirement of particularized
testimony and linking argument. According to NexStep,
for certain “easily understandable” technologies, a
patentee simply need not offer particularized testimony
and linking argument from a skilled artisan. We reject this
argument because it is contrary to both our precedent and
the policies underlying why we require particularized
testimony and linking argument.
NexStep’s ask for an “easily understandable”
technology exception is particularly unpersuasive because
the cases in which we explicated the particularized
testimony and linking argument requirement dealt with
“easily understandable” technologies. In 1989, we first
coined the phrase “particularized testimony and linking
argument” in the seminal case of Lear Siegler, noting that
“the three Graver Tank [function-way-result] elements
must be presented in the form of particularized testimony
and linking argument.” Lear Siegler, 873 F.2d at 1426.
Two years later, we explained that our precedent “at least
requires the evidence to establish what the function, way,
and result of both the claimed device and the accused
device are, and why those functions, ways, and results are
substantially the same.” Malta, 952 F.2d at 1327 n.5. Lear
Siegler and Malta respectively dealt with inventions for
box springs used with a mattress and handbells used in
churches and schools. Yet we still required particularized
testimony and linking argument to prove infringement
under the doctrine of equivalents. That this court
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explicated the particularized-testimony-and-linking-
argument requirement in cases dealing with “easily
understandable” technologies cuts sharply against now
making an exception that would apply to those very same
cases.
Indeed, more than 30 years later, we have stayed the
course. In VLSI, the jury was confronted with the “not-so
easily understandable” technology of managing the
memory-operating-voltage and clock speed in electronic
devices. Consistent with our precedent, the patentee was
required to provide “particularized testimony and linking
argument as to the insubstantiality of the differences
between the claimed invention and the accused device.”
VLSI, 87 F.4th at 1343 (collecting cases). Thus, from
handbells to complex electronics, particularized testimony
and linking argument is always required.
In fact, we have never recognized a technology-specific
exception to the evidentiary rules governing the doctrine of
equivalents. Simply put, our precedent requires
particularized testimony and linking argument, regardless
of the complexity or the simplicity of the underlying
technology. See, e.g., VLSI, 87 F.4th at 1336–39, 1342–45
(patents for adjusting operating voltage and clock speed in
electronic devices); Akzo Nobel Coatings, Inc. v. Dow Chem.
Co., 811 F.3d 1334, 1336–37, 1342–43 (Fed. Cir. 2016)
(patent “directed to an extrusion process that generates
low viscosity aqueous polymer dispersions”); Gemalto S.A.
v. HTC Corp., 754 F.3d 1364, 1366, 1374 (Fed. Cir. 2014)
(“The asserted claims are directed to applications that are
converted from a high level programming language into
another format that is suitable for resource-constrained
computing devices.”); AquaTex Indus., Inc. v. Techniche
Sols., 479 F.3d 1320, 1323, 1328–29 (Fed. Cir. 2007) (“The
’977 patent claims a method for cooling a person through
evaporation by use of a multi-layered, liquid-retaining
composite material in evaporative cooling garments.”);
Paice, 504 F.3d at 1296–1301, 1304–06 (“The three patents
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 37
at issue in this case relate to drive trains for hybrid electric
vehicles.”); Tex. Instruments, 90 F.3d at 1560, 1566–67
(“These patents claim different aspects of a process for
encapsulating electronic components in plastic.”); Malta,
952 F.2d at 1321–22, 1327 (“The patent in suit . . . is
directed to improvements in the design of handbells, of the
type used by music groups in churches, schools, and the
like.”); Lear Siegler, 873 F.2d at 1423–26 (springs used in a
mattress’s box spring assembly); see also Malta., 952 F.2d
at 1330 (Michel, J., concurring) (“The simplicity of the
[claimed invention], so emphasized by the dissent, is not
relevant either. . . . [T]he rule of Lear Siegler is a
prophylactic rule of general applicability. As such, it must
cover the whole range of infringement cases, many of which
do indeed involve complex technology.”); id. at 1334
(Newman, J., dissenting) (“[T]hese [evidentiary]
requirements must be fulfilled no matter how simple the
invention.”).7
It makes sense that the patentee must provide
particularized testimony and linking argument in every
7 NexStep cites only WCM Industries, Inc. v. IPS
Corporation, 721 F. App’x 959 (Fed. Cir. 2018), to support
its argument. That case is non-precedential. It is also
inapposite. In that case, we reversed the district court’s
grant of judgment as a matter of law because the patentee
“provided sufficient” evidence under the doctrine of
equivalents. Id. at 969. Along the way, we reaffirmed that
“the difficulties and complexities of the doctrine[] must be
presented to the jury or other fact-finder through the
particularized testimony of a person of ordinary skill in the
art.” Id. at 966 (internal quotation marks omitted)
(quoting AquaTex, 479 F.3d at 1329). Thus, we merely
found, on the facts of that case, the patentee had presented
particularized testimony and linking argument sufficient
to support the jury’s verdict.
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case because “the difficulties and complexities of the
doctrine require” it. AquaTex, 479 F.3d at 1329 (emphasis
added); see also Tex. Instruments, 90 F.3d at 1566–67 (“Our
court set forth these evidentiary requirements in those
earlier cases because, although the standard for
infringement under the doctrine of equivalents is simple to
articulate, it is conceptually difficult to apply.”). The
difficulties and complexities of the doctrine are present
regardless of the simplicity of the underlying technology.
Even if a jury understands the underlying technology, the
doctrine of equivalents itself introduces a distinct and
complex inquiry that requires appropriate guidance. See
AquaTex, 479 F.3d at 1329; Tex. Instruments, 90 F.3d at
1566–67.
Accordingly, regardless of the technology at issue,
patentees must still present juries with particularized
testimony and linking argument to ensure that the jury
does not misapply the doctrine and thereby stray beyond
the doctrine’s “properly limited” role. VLSI, 87 F.4th at
1342 (citing Warner-Jenkinson, 520 U.S. at 35, 39). An
example of a misapplication of the doctrine is if the
factfinder relies on “merely generalized testimony as to
overall similarity.” Tex. Instruments, 90 F.3d at 1568. By
guiding the jury’s attention to particularized testimony and
linking argument that compares the accused elements to
the claimed limitation at issue, we avoid inviting the jury
to resort to improper generalized comparisons between the
overall claimed invention and the accused product. This
requirement therefore “ensure[s] that a jury is provided
with the proper evidentiary foundation from which it may
permissibly conclude that a claim limitation has been met
by an equivalent.” Comark Commc’ns, Inc. v. Harris Corp.,
156 F.3d 1182, 1188 (Fed. Cir. 1998).
In summary, NexStep has provided no persuasive
reason to break with decades of our precedent, which has
been explicit and consistent in requiring particularized
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 39
testimony and linking argument regardless of the
complexity or simplicity of the underlying technology.
IV.
We briefly address two points that are central to the
dissent’s disagreement with the majority opinion.
First, the dissent states that “[t]he majority concocts a
rigid new rule that in all cases a patentee must present
expert opinion testimony to prove infringement under the
doctrine of equivalents,” and “disagree[s] with the
majority’s extrapolation that expert testimony is always
required.” Dissenting Op. 7. That is not correct, for our
discussion of the use of expert testimony in proving
infringement under the doctrine of equivalents is limited
to quoting the standard articulated in AquaTex Industries,
Inc. v. Techniche Solutions: “[B]oth the Supreme Court and
this court have made clear that the evidence of equivalents
must be from the perspective of someone skilled in the art,
for example through testimony of experts or others versed
in the technology; by documents, including texts and
treatises; and, of course, by the disclosures of the prior art.”
479 F.3d at 1329 (cleaned up); see id. (“[W]hen the patent
holder relies on the doctrine of equivalents,” we “require
that evidence be presented to the jury or other fact-finder
through the particularized testimony of a person of
ordinary skill in the art, typically a qualified expert.”); see
also Maj. Op. 20.
Second, according to the dissent, “not only did
Dr. Selker testify that several button presses are the same
as a single action in the context of the doctrine of
equivalents, but Dr. Selker also testified on the same point
in the context of literal infringement.” Dissenting Op. 5.
But testifying that several button presses are the same as
a single action is not the correct test. To prove
infringement under the doctrine of equivalents (at least
when a party, like NexStep, is relying on the function-way-
result framework), there must be particularized testimony
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 40
explaining why “the accused product performs
‘substantially the same function in substantially the same
way to obtain the same result’”—not testimony that the
accused product is the same as (or meets) the claim
limitation. Mylan Institutional LLC v. Aurobindo Pharma
Ltd., 857 F.3d 858, 866 (Fed. Cir. 2017) (quoting Graver
Tank, 339 U.S. at 608). By finding no literal infringement,
the jury rejected NexStep’s position that “several button
presses” are the same as a single action, and instead
necessarily concluded that several button presses by a user
are multiple actions. For NexStep’s back-up infringement
theory under the doctrine of equivalents, then, NexStep
had to pivot and explain, in the alternative, why those
several button presses—if found to entail multiple
actions—nevertheless perform substantially the same
function in substantially the same way to obtain the same
result as the claimed “single action.” But NexStep never
provided that why.
V.
Based on how we resolve the infringement issues in
this case, we need not address NexStep’s damages
argument or Comcast’s conditional cross appeal.8 We have
considered the parties’ remaining arguments and find
8 Comcast’s express making of its cross-appeal
conditional means that we need not address validity if we
affirm non-infringement and therefore may dismiss the
cross-appeal. We also note that Comcast exclusively
asserted invalidity under § 101 as a defense to liability; it
did not assert a counterclaim for a declaratory judgment of
invalidity. See NexStep, Inc. v. Comcast Cable Commc’ns,
LLC, No. 19-cv-1031, ECF No. 40 at 32 (D. Del. Dec. 17,
2019); see also Cardinal Chem. Co. v. Morton Int’l, Inc., 508
U.S. 83, 93–94 (1993) (distinguishing between mootness of
invalidity defense and mootness of declaratory judgment
claim asserting invalidity).
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 41
them unpersuasive. For the foregoing reasons, we affirm
the district court’s final judgment with respect to non-
infringement of the ’009 and ’802 patents, and we dismiss
Comcast’s cross-appeal.
AFFIRMED AS TO THE APPEAL AND DISMISSED
AS TO THE CROSS-APPEAL
COSTS
Costs to Comcast.
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United States Court of Appeals
for the Federal Circuit
______________________
NEXSTEP, INC.,
Plaintiff-Appellant
v.
COMCAST CABLE COMMUNICATIONS, LLC,
Defendant-Cross-Appellant
______________________
2022-1815, 2022-2005, 2022-2113
______________________
Appeals from the United States District Court for the
District of Delaware in No. 1:19-cv-01031-RGA, Judge
Richard G. Andrews.
______________________
REYNA, Circuit Judge, concurring-in-part and dissenting-
in-part.
I am pleased to concur in part with the majority
opinion. I dissent only to that portion of the majority
opinion that affirms the district court’s entry of judgment
as a matter of law of non-infringement of the ’009 patent.
I dissent for two reasons. First, I believe the jury’s verdict
that Comcast infringed the ’009 patent under the doctrine
of equivalents is supported by substantial evidence.
Second, I believe the majority’s new rule that patentees
must always present expert opinion testimony to prove
infringement under the doctrine of equivalents is incorrect
and contrary to existing precedent. Thus, I would reverse
the district court’s decision that disturbed the jury verdict.
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 2
The majority is correct that in determining whether to
overturn a jury verdict, the correct law in this case is that
of the Third Circuit. The Third Circuit respects jury
verdicts. Accordingly, “entry of judgment as a matter of law
is a ‘sparingly’ invoked remedy.” Marra v. Phila. Hous.
Auth., 497 F.3d 286, 300 (3d Cir. 2007), as amended
(Aug. 28, 2007) (citation omitted). It is only in “rare cases”
that, “following a jury verdict, judgment as a matter of law
[is] warranted.” Fair Hous. Council v. Main Line Times,
141 F.3d 439, 442 (3d Cir. 1998); see also Pitts v. Delaware,
646 F.3d 151, 152 (3d Cir. 2011). A “court may grant a
judgment as a matter of law contrary to the verdict only if
‘the record is critically deficient of the minimum quantum
of evidence’ to sustain the verdict.” Acumed LLC v.
Advanced Surgical Servs., Inc., 561 F.3d 199, 211 (3d Cir.
2009) (citation omitted). When a jury has heard extensive
testimony, judgment as a matter of law is “only . . .
appropriate in the extraordinary circumstance that none of
that evidence could lead a reasonable jury to [reach its
conclusion].” Avaya Inc., RP v. Telecom Labs, Inc., 838 F.3d
354, 373 (3d Cir. 2016) (emphasis added).
We must “view[] the evidence in the light most
favorable to the nonmovant and giv[e] it the advantage of
every fair and reasonable inference.” Lightning Lube, Inc.
v. Witco Corp., 4 F.3d 1153, 1166 (3d Cir. 1993) (citation
omitted). The party seeking judgment as a matter of law
“must show that the jury’s findings, presumed or express,
are not supported by substantial evidence.” Interactive
Pictures Corp. v. Infinite Pictures, Inc., 274 F.3d 1371, 1376
(Fed. Cir. 2001) (citation omitted); see also Lightning Lube,
4 F.3d at 1184. Substantial evidence is “such relevant
evidence as a reasonable mind might accept as adequate to
support a conclusion.” Consol. Edison Co. v. NLRB, 305
U.S. 197, 229 (1938). Thus, “the court must determine
whether a reasonable jury could have found for the
prevailing party.” Starceski v. Westinghouse Elec. Corp., 54
F.3d 1089, 1095 (3d Cir. 1995) (citation omitted). It is
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 3
against this backdrop that we must analyze whether
substantial evidence supports the jury’s verdict.
A non-technical non-complex factual issue was put to
the jury: whether the process of several button presses is
equivalent to a “single action,” a single press. The jury
heard evidence from both parties, received instructions
from the court, and then answered in the affirmative. Yet,
the majority overrides this finding based on its belief that
NexStep failed to provide “particularized testimony and
linking argument as to the insubstantiality of the
differences between the claimed invention and the accused
device.” Maj. Op. 21 (quoting VLSI Tech. LLC v. Intel
Corp., 87 F.4th 1332, 1343 (Fed. Cir. 2023)).
In my view, the majority commits two errors. First, the
majority analyzes NexStep’s evidence of infringement
under the doctrine of equivalents in a vacuum and fails to
adhere to the substantial evidence standard of review.
Second, the majority’s reasoning imposes a new rule that a
patentee must present expert opinion testimony to prove
infringement under the doctrine of equivalents.
I
The majority disregards the totality of the evidence
presented and instead analyzes NexStep’s evidence of
infringement under the doctrine of equivalents in a
vacuum. The majority unduly focuses on testimony from
NexStep’s expert, Dr. Selker, on the function-way-result
test of the doctrine of equivalents. Maj. Op. 22–29. In
doing so, the majority ignores both the context in which the
jury heard this testimony and the other evidence the jury
received that is probative as to the question of equivalence.
This approach is contrary to our precedent, which does not
require expert witnesses to “re-start [their] testimony at
square one when transitioning to a doctrine of equivalents
analysis.” Paice LLC v. Toyota Motor Corp., 504 F.3d 1293,
1305 (Fed. Cir. 2007). This is because juries do not consider
evidence in categories, but rather, consider the totality of
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 4
the evidence presented. Brooktree Corp. v. Advanced Micro
Devices, 977 F.2d 1555, 1573 (Fed. Cir. 1992).
Here, NexStep presented its doctrine of equivalents
evidence in the context of its literal infringement evidence.
See VLSI, 87 F.4th at 1343 (“[Patentee’s] equivalents
contention is best understood in light of its literal-
infringement case.”). And we must presume the jury
considered all of NexStep’s evidence when rendering its
verdict, rather than only a subset of the evidence. See i4i
Ltd. P’ship v. Microsoft Corp., 598 F.3d 831, 849 (Fed. Cir.
2010) (“[W]e assume the jury considered all the evidence”
presented in rendering its verdict.). When viewed through
that lens, it becomes clear that under Third Circuit law,
NexStep provided a legally sufficient evidentiary basis for
a reasonable jury to decide in its favor.
This is not to say that literal infringement testimony
alone is sufficient to show infringement under the doctrine
of equivalents. As we have recognized, “[t]he evidence and
argument on the doctrine of equivalents cannot merely be
subsumed in plaintiff’s case of literal infringement.” Lear
Siegler, Inc. v. Sealy Mattress Co., 873 F.2d 1422, 1425
(Fed. Cir. 1989). But that is not the case here. Rather,
when literal infringement evidence is coupled with
evidence of infringement under the doctrine of equivalents,
the combination of evidence can sufficiently show
infringement under the doctrine of equivalents. Id.; see
also Paice, 504 F.3d at 1305 (“Indeed, we think it desirable
for a witness to incorporate earlier testimony in order to
avoid duplication.”).
For example, the majority faults Dr. Selker for
allegedly failing to identify “a particular element or
elements” that is equivalent to the “single action”
limitation. Maj. Op. 24. Yet the majority recognizes that
Dr. Selker identified “several button presses” as the critical
function. Maj. Op. 25. The majority also acknowledges
that Dr. Selker “identified three separate literal
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 5
infringement theories (XfinityAssistant, Troubleshooting
Card, and Diagnostic Check), each with its own distinct
series of button presses” when addressing literal
infringement. Id. And Dr. Selker identified the distinct
“series of button presses” when testifying about literal
infringement under each of these theories. J.A. 431, 329:4–
330:16; J.A. 434, 340:11–341:8; J.A. 437, 353:15–354:5. So,
when Dr. Selker later referred to “several button presses”
when addressing infringement under the doctrine of
equivalents, the jury could reasonably conclude that Dr.
Selker was referring them to specific elements he identified
during his literal infringement testimony. Paice, 504 F.3d
at 1305 (“The fact that [patentee’s expert] did not explicitly
[incorporate his earlier testimony] does not mean he did
not implicitly [do so].”).
The majority also faults Dr. Selker for “never stat[ing]
or explain[ing] why several button presses are
insubstantially different from a single action.” Maj. Op. 32.
This is not a shortcoming of Dr. Selker’s testimony, but
rather, the majority’s interpretation and restrictive review
of Dr. Selker’s testimony. To be clear, not only did Dr.
Selker testify that several button presses are the same as
a single action in the context of the doctrine of equivalents,
but Dr. Selker also testified on the same point in the
context of literal infringement. Dr. Selker first testified
that:
[E]ven pressing [one] button, you have to see the
button, you have to go think about it, you have to
move your finger to it, you have to go and press it
and you have to see that it’s responded. So
whatever a single action is, whether a single press
or other things, there’s some parts to it. And I call
those steps a single action.
J.A. 434, 342:12–18. Further, Dr. Selker also testified that
“multiple steps might be contained in a single action,”
because, “[f]or example, when you throw a baseball, you
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 6
pick it up, you orient it, you get it in your palm, you throw
it. There’s several steps to making a baseball, to throwing
a baseball.” J.A. 460, 445:1–4. Finally, when discussing
the doctrine of equivalents, Dr. Selker testified that
“[w]hen you . . . diagnose your device, you’re going through
a single action. It might be that there’s several button
presses along the way, but I say that’s the same [as a single
action].” J.A. 445, 384:5–8. The majority fails to address
the substance of his opinions on this point.
In short, Dr. Selker testified that several button
presses are a single action because single actions have
multiple steps, such as throwing a baseball. Further, the
steps a user takes to perform one button press are the same
regardless of whether more than one press is taken. Yet
even if several button presses are not literally a single
action, the two are nonetheless equivalent. Having heard
this evidence and argument, the jury should be permitted
to reject Dr. Selker’s first opinion but accept his second
opinion, which is inherently based on his first opinion.
The majority’s remaining criticisms of Dr. Selker’s
testimony are similarly unjustified and unsupported by the
record. For example, the majority believes that “it is not
clear that Dr. Selker identified the ‘way’ that the accused
product or the claim limitation operates.” Maj. Op. 27. But
the record is not “critically deficient of the minimum
quantum of evidence” on this point. See Acumed LLC, 561
F.3d at 211; J.A. 428–29, 318:19–322:8 (Dr. Selker
demonstrating the functionality of Comcast’s product);
J.A. 434–36, 340:11–349:13 (Dr. Selker explaining how
Comcast’s product and the “single action” claim limitation
operate); J.A. 431, 329:4–330:16 (Dr. Selker explaining
several different ways Comcast’s product starts the
claimed “support session”); J.A. 437, 353:15–354:5 (Dr.
Selker explaining how several different single button clicks
within Comcast’s product start a “system check”).
Similarly, the majority asserts that “Dr. Selker merely
testified that something is going to happen so that the
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 7
modem works.” Maj. Op. 28. The record indicates
otherwise. As a result, this is not “the extraordinary
circumstance that none of that evidence could lead a
reasonable jury to [reach its conclusion].” See Avaya Inc.,
RP, 838 F.3d at 373; J.A. 434–35, 342:19–343:8 (Dr. Selker
explaining how Comcast’s product performs the claimed
communication “with a home gateway” via the cloud);
J.A. 435–36, 345:5–349:13 (Dr. Selker explaining Comcast
technical documents that show how the claimed
“responsive to a single action” limitation causes the
subsequent claim limitations to occur in Comcast’s
product).
A motion for judgment as a matter of law is a “narrow
inquiry.” Marra, 497 F.3d at 300. That narrow inquiry
must end “when there is shown to be substantial evidence,
on the record as a whole, as could have been accepted by a
reasonable jury as probative of the issue.” Nat’l Presto
Indus., Inc. v. W. Bend Co., 76 F.3d 1185, 1192 (Fed.
Cir. 1996) (citation omitted). As illustrated above, Dr.
Selker’s testimony is substantial evidence on which a
reasonable jury could find for NexStep. Thus, the inquiry
should end. But there is more.
II
The majority concocts a rigid new rule that in all cases
a patentee must present expert opinion testimony to prove
infringement under the doctrine of equivalents. The
majority’s new rule is superficial because it fails to
recognize that each individual patent infringement case
presents unique facts and circumstances. There is no
cookie-cutter approach to patent infringement.
I agree with the majority’s observation that “our
precedent at least requires the evidence to establish what
the function, way, and result of both the claimed device and
the accused device are, and why those functions, ways, and
results are substantially the same.” Maj. Op. 35 (internal
quotation marks and some emphasis omitted) (quoting
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 8
Malta v. Schulmerich Carillons, Inc., 952 F.2d 1320,
1327 n.5 (Fed. Cir. 1991)); see also Lear Siegler, 873 F.2d at
1425. But I disagree with the majority’s extrapolation that
expert testimony is always required. Indeed, our precedent
establishes that “testimony of experts” is an “example” of
the type of evidence that can be employed in a doctrine of
equivalents analysis. AquaTex Indus., Inc. v. Techniche
Sols., 479 F.3d 1320, 1329 (Fed. Cir. 2007) (“[E]vidence of
equivalents must be from the perspective of someone
skilled in the art, for example through testimony of experts
or others versed in the technology; by documents, including
texts and treatises; and, of course, by the disclosures of the
prior art.” (emphasis added) (citation and internal
quotation marks omitted)).
There is also no doubt that in complex cases, expert
testimony must be offered. See VLSI, 87 F.4th at 1335–39
(describing memory-operating-voltage and clock speed of
electronic devices). But the same is not true where the
technology or the specific doctrine of equivalents issue is so
simple that evidence other than expert testimony is more
than adequate for a jury to understand the issues and find
equivalence.1 That is the case here. While I would find Dr.
Selker’s testimony is sufficient to support the jury’s verdict,
I would also find that the jury did not need expert
testimony to answer the technologically-simple question
presented here of whether several button presses are
equivalent to a “single action.”
1 Such an approach would also be consistent with our
law on expert testimony for nonobviousness. See
Intercontinental Great Brands LLC v. Kellogg N. Am. Co.,
869 F.3d 1336, 1348 (Fed. Cir. 2017) (“[S]ome cases involve
technologies and prior art that are simple enough that no
expert testimony is needed.” (citation omitted)); Inline
Plastics Corp. v. Lacerta Grp., LLC, 97 F.4th 889, 897 (Fed.
Cir. 2024).
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NEXSTEP, INC. v. COMCAST CABLE COMMUNICATIONS, LLC 9
Indeed, one of our cases already resolves this exact
issue. In WCM Industries, Inc. v. IPS Corporation, we
found:
[O]ur precedent does not require opinion testimony,
and certainly does not require expert opinion
testimony, for a finding of equivalence. Rather,
“[p]roof can be made in any form: through
testimony of experts or others versed in the
technology; by documents, including texts and
treatises; and, of course, by the disclosures of the
prior art.” . . . [W]here the technology is “easily
understandable without the need for expert
explanatory testimony,” expert testimony is not
required.
721 F. App’x 959, 966–67 (Fed. Cir. 2018) (citations
omitted). While this decision is non-precedential, I find
that it accurately characterizes our precedent which,
again, largely speaks in terms of “evidence” generally, or at
times “testimony,” but not expert testimony specifically.
Maj. Op. 21–22, 35–37 (collecting cases on testimony
generally).
The majority rationalizes its new rule of “evidentiary
requirements” by reasoning that the doctrine of
equivalents itself is “conceptually difficult” and therefore
“the difficulties and complexities of the doctrine require”
rigid rules. Maj. Op. 21, 37. The majority goes on, stating
that: “The difficulties and complexities of the doctrine are
present regardless of the simplicity of the underlying
technology.” Maj. Op. 37. I disagree. The majority claims
its new rule is necessary so that experts may ease the jury’s
burden of understanding the complexity of a legal doctrine.
But our law does not require, and in fact it chastises,
witnesses who testify as to the meaning of legal doctrines
themselves. See Fed. R. Evid. 702 (An expert witness must
“help the trier of fact to understand the evidence or to
determine a fact in issue.” (emphasis added)); see also
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Stobie Creek Invs. LLC v. United States, 608 F.3d 1366,
1383–84 (Fed. Cir. 2010) (The district court properly
excluded expert testimony that “would not assist the court
because the opinion concerned a question of law, not fact.”
(citation and internal quotation marks omitted)). Instead,
the proper way to remedy the complexity of legal doctrines
is for the district court to instruct the jury on the law, as
the district court did here. Trading Techs. Int’l, Inc. v.
eSpeed, Inc., 595 F.3d 1340, 1360 (Fed. Cir. 2010) (An
expert cannot “usurp the district court’s role of instructing
the jury on the law.”). At least in the Third Circuit, the law
recognizes the role and resolve of the jury and will not,
absent compelling reasons not presented here, reverse a
jury verdict that stands on substantial evidence.
* * *
This case does not present extraordinary
circumstances. Because I believe the majority invades the
province of the jury by overturning a reasonable verdict
that is supported by substantial evidence in this case and
by imposing an unnecessary new rule in all future doctrine
of equivalents cases to come, I respectfully dissent in part.
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