Case: 20-2167 Document: 40 Page: 1 Filed: 04/01/2022
United States Court of Appeals
for the Federal Circuit
______________________
GENUINE ENABLING TECHNOLOGY LLC,
Plaintiff-Appellant
v.
NINTENDO CO., LTD., NINTENDO OF AMERICA
INC.,
Defendants-Appellees
______________________
2020-2167
______________________
Appeal from the United States District Court for the
Western District of Washington in No. 2:19-cv-00351-RSM,
Judge Ricardo S. Martinez.
______________________
Decided: April 1, 2022
______________________
DEVAN V. PADMANABHAN, Padmanabhan & Dawson,
PLLC, Minneapolis, MN, argued for plaintiff-appellant.
Also represented by ERIN DUNGAN, PAUL J. ROBBENNOLT.
JERRY A. RIEDINGER, Perkins Coie, LLP, Seattle, WA,
argued for defendants-appellees. Also represented by
KEVIN ANDREW ZECK; ANDREW DUFRESNE, DAVID R.
PEKAREK KROHN, Madison, WI.
______________________
Before NEWMAN, REYNA, and STOLL, Circuit Judges.
Case: 20-2167 Document: 40 Page: 2 Filed: 04/01/2022
2 GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD.
REYNA, Circuit Judge.
Genuine Enabling Technology LLC sued Nintendo Co.,
Ltd. and Nintendo of America, Inc. accusing five products
of infringing certain claims of U.S. Patent No. 6,219,730.
The U.S. District Court for the Western District of Wash-
ington construed the term “input signal,” which appears in
all the asserted claims, consistent with the defendants’ pro-
posed construction, and on that basis granted summary
judgment of non-infringement in favor of the defendants.
Genuine appeals, arguing that the district court erred in
construing the limitation by improperly relying on extrin-
sic evidence and by improperly finding that the inventor,
Mr. Nguyen, disclaimed certain claim scope during prose-
cution. We conclude that the district court erred in its con-
struction of “input signal” and construe the term to mean
“a signal having an audio or higher frequency.” Accord-
ingly, we reverse the district court’s grant of summary
judgment and remand for further proceedings consistent
with this opinion.
BACKGROUND
The ’730 Patent
On June 20, 1998, inventor Nghi Nho Nguyen filed a
patent application that issued on April 17, 2001, as U.S.
Patent No. 6,219,730. The ’730 patent is titled “Method
and Apparatus for Producing a Combined Data Stream and
Recovering Therefrom the Respective User Input Stream
and at Least One Additional Input Signal.” The ’730 pa-
tent discloses technology for combining data streams that
Mr. Nguyen conceived when developing a “voice mouse”
that conserved computer resources. Appellant’s Br. 7–8.
According to the ’730 patent, in the prior art, comput-
ers received user input via a “user input device” or “UID,”
such as a mouse or keyboard. ’730 patent col. 1 ll. 14–18,
col. 3 ll. 26–30. Computers also used “input/output” or
“I/O” cards to process various types of signals. Id. at col. 1
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GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD. 3
ll. 18–22. As an example of an I/O card, a sound card would
be used to receive speech input from a microphone and to
transmit speech output to a speaker. Id. at col. 3 ll. 26–30.
The ’730 patent explains that devices and cards share com-
puter resources and that their configuration can be cum-
bersome:
Devices and cards require and share common com-
puter resources such as the direct memory access
(DMA) channels and the interrupt request (IRQ)
services. Computer resources for each device or
each card equipped in a computer must be config-
ured, or assigned, to pre-arranged memory loca-
tions that are limited in number. Configuration
setup for computer resources is cumbersome and
sometimes causes conflict in running software.
Id. at col. 1 ll. 21–28.
To solve these problems, the ’730 patent “offers a new
kind of UID utilizing the computer resources efficiently.”
Id. at col. 1 ll. 41–42. The embodiment shown in Figure 1B
“eliminates the [computer’s] sound card” so that the UID
(i.e., mouse 18) “directly receives speech input from micro-
phone 16 and transmits speech output to speaker 17.” Id.
at col. 3 ll. 30–36. This arrangement involves the use of a
“framer” that (i) receives input from the UID and external
device (e.g., speaker or microphone), and (ii) “synchro-
nize[s] and merge[s]” those data streams into a “combined
data stream.” Id. at col. 4 ll. 28–31. Claim 1 is representa-
tive and recites:
1. A user input apparatus operatively coupled to a
computer via a communication means additionally
receiving at least one input signal, comprising:
user input means for producing a user in-
put stream;
input means for producing the at least one
input signal;
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4 GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD.
converting means for receiving the at least
one input signal and producing therefrom
an input stream; and
encoding means for synchronizing the user
input stream with the input stream and en-
coding the same into a combined data
stream transferable by the communication
means.
Id. at col. 7 l. 61–col. 8 l. 4.
During prosecution, the examiner rejected pending
claims 1–27 as obvious. J.A. 1762, 1767–69. In particular,
the examiner rejected pending claims 1, 16, and 23 as ob-
vious in light of U.S. Patent No. 5,990,866 (“Yollin”).
J.A. 1768–69.
Yollin is titled “Pointing Device with Integrated Physi-
ological Response Detection Facilities.” Yollin explains
that prior art pointing devices (e.g., a mouse, joystick, or
stylus) typically provided two-dimensional motion infor-
mation for a cursor (i.e., positional change information) as
well as signals for pushing a button (i.e., user selection in-
formation). Yollin at col. 1 ll. 27–38. According to Yollin,
a subset of prior art devices also processed input known as
biofeedback from physiological sensors, but those systems
generally “require a separate dedicated physiological re-
sponse input device that consumes a valuable I/O port of
the computer system, and . . . rel[y] on a specialized dedi-
cated program.” Id. at col. 1 ll. 53–62. Yollin thus disclosed
“a pointing device with integrated physiological response
detection facilities” that “does not consume excess I/O
ports.” Id. at col. 1 l. 66–col. 2 l. 6.
Yollin further described the types of physiological re-
sponse sensors that could be used. Yollin’s invention could
use “any of a number of alternative devices which measure
any of a number of physiological responses of a user who
contacts the sensor(s).” Id. at col. 3 l. 64–col. 4 l. 2.
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GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD. 5
Exemplary sensors included “a [Galvanic Skin Response or
GSR] sensor, an electromyograph (muscle tension), electro-
cardiograph (heart activity), electroencephalograph (brain
activity), thermometer (skin temperature), blood pressure
sensor, and the like.” Id. at col. 4 ll. 5–10. Yollin, however,
did not specifically discuss the frequencies of the signals
generated by the physiological sensors.
With respect to the “input signal” limitation of pending
claims 1, 16, and 23, the examiner cited Yollin’s teaching
of “input information received from motion translation unit
102, user selection unit 104 and physiological response sen-
sor(s) 106” as grounds for rejection. J.A. 1768 (citing Yollin
at col. 5 ll. 16–18).
Mr. Nguyen responded to the office action on Septem-
ber 28, 2000, arguing that Yollin failed to adequately teach
the limitation. Mr. Nguyen distinguished the “slow vary-
ing” physiological response signals discussed in Yollin from
the “signals containing audio or higher frequencies” con-
templated by his invention on the ground that the latter
signals pose a signal “collision” problem solved by Mr. Ngu-
yen’s inventions:
Yollin’s invention . . . utilizes various implementa-
tions and configurations for receiving input from
motion translation unit 102, user selection unit 104
and physiological response sensor(s) 106, and for
processing their information prior to communica-
tion to the host system via communication inter-
face 108 and channel 112. These configurations are
standard and well-known to the artisan. However,
Yollin only uses the configuration to receive the
slow varying signal coming from the physiological
response sensor(s). Yollin is not motivated and
does not anticipate their use for receiving signals
containing audio or higher frequencies in place of
the physiological response sensor(s). The high fre-
quency input signal, which comes from a source
Case: 20-2167 Document: 40 Page: 6 Filed: 04/01/2022
6 GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD.
different from those of motion and selection units,
will run asynchronously relative to, and collide
with, the other signals. Yollin’s invention does not
teach or suggest any approach for receiving and re-
covering that kind of input signal.
J.A. 1784 (emphasis added). Mr. Nguyen then reiterated
that distinction between Yollin and his inventions:
[Yollin] utilizes . . . a controller to receive positional
change information, user selection information and
physiological change information to generate . . . a
composite signal but does not anticipate its use with
signals containing audio or higher frequencies. Us-
ing a controller to generate the composite control
signal out of the information changes, which are
slow-varying, is standard and not worth [being]
mentioned in Yollin’s description. Difficulties will
arise when one signal runs asynchronously relative
to another signal and fast. Yollin’s patent does not
teach or suggest any method for the controller to
receive and recover such signals. In contrast, this
invention describes, in its representative embodi-
ments, how to combine the data from a UID
(mouse) and from a high-frequency signal, via a
framer, which is unique and novel.
J.A. 1785 (emphasis added). Mr. Nguyen made this essen-
tial argument a third time:
Yollin’s method of using the controller to generate
a composite signal only works for slow varying sig-
nals. In contrast, this invention teaches the arti-
san the ways of synchronizing and encoding two
sources of signals into a combined data, via a
framer, before sending onto a communication link,
and of recovering from the received combined data
the original information of the respective signals.
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GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD. 7
Id. (emphasis added). In late November 2000, the exam-
iner entered an examiner’s amendment and allowed the
claims. See J.A. 1796–810.
The District Court Action
On February 8, 2017, Genuine Enabling Technology
LLC (“Genuine”) filed an action against Nintendo Co., Ltd.
and Nintendo of America, Inc. (collectively, “Nintendo”) in
the U.S. District Court for the District of Delaware.
J.A. 63. Genuine alleged that five Nintendo products in-
fringe the ’730 patent: (1) the Wii Remote and Wii Remote
Plus; (2) the Nunchuk; (3) the WiiU Game Pad; (4) the
Switch Joy-Con Controller; and (5) the Nintendo Switch
Pro Controller. Genuine Enabling Tech. LLC v. Nintendo
Co., No. C19-351RSM, 2020 WL 4366163, at *1 (W.D.
Wash. July 30, 2020). Specifically, Genuine alleged that
these products contain functionality that infringe claims
10, 14–18, 21–23, and 25 of the ’730 patent. Id. On March
11, 2019, the case was transferred to the Western District
of Washington. Id. at *4; J.A. 666.
In early 2020, the parties submitted claim construction
briefing in which they disputed the proper construction of
the claim term “input signal” in all asserted claims. 1
J.A. 1440–52, 1655–77. Genuine proposed the construc-
tion, “a signal having an audio or higher frequency.”
J.A. 1677. Nintendo proposed the following narrower con-
struction:
A signal containing audio or higher frequencies.
Mr. Nguyen disclaimed signals that are 500 Hertz
(Hz) or less. He also disclaimed signals that are
generated from positional change information, user
selection information, physiological response
1 The district court held a Markman hearing on Feb-
ruary 24, 2020. See J.A. 3263–321.
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8 GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD.
information, and other slow-varying information.
Alternatively, indefinite.
J.A. 1448. In support, Nintendo submitted a declaration
by Dr. Howard Chizeck, which discussed the features and
operation of physiological sensors such as those disclosed
in the Yollin reference. J.A. 1542–55. Dr. Chizeck included
a chart titled “Range and Frequency of Select Physiological
Phenomena” and indicated that the information in the
chart came from a reference he called “Yuce, et al.”
J.A. 1551. The chart provided frequency ranges for signals
associated with various physiological phenomena, includ-
ing a range of 10–500 Hz for EMG (electromyogram). Id.
Based on this chart, Dr. Chizeck opined that “the maxi-
mum frequency of the signals from physiological sensors
described by Yollin is at least 500 Hz.” J.A. 1553. Relying
on Dr. Chizeck’s declaration, Nintendo argued that a per-
son of ordinary skill in the art would have understood
Yollin to teach physiological sensor signals having maxi-
mum frequencies of at least 500 Hz, and that, therefore,
Mr. Nguyen had disclaimed all such signals when he dis-
tinguished Yollin from his inventions during prosecution.
J.A. 1450–51. Nintendo accordingly opposed Genuine’s
broader construction, which encompassed the range of fre-
quencies that humans can hear (20 Hz to 20,000 Hz).
J.A. 1451.
On January 23, 2020, Nintendo moved for summary
judgment of non-infringement, which was predicated on
the district court’s acceptance of its claim construction of
“input signal.” J.A. 2465–90. Nintendo argued that its ac-
cused controllers produce the types of slow-varying signals
that Mr. Nguyen disclaimed during prosecution when he
distinguished his inventions from the Yollin reference. See
J.A. 2482–84.
On July 30, 2020, the district court issued an order
granting Nintendo’s motion for summary judgment. Gen-
uine, 2020 WL 4366163, at *1. The court construed the
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GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD. 9
“input signal” limitation in all asserted claims to mean
“signals above 500 Hz and excluding signals generated
from positional change information, user selection infor-
mation, physiological response information, and other
slow-varying information,” consistent with Nintendo’s pro-
posed construction. Id. at *10. The court interpreted Mr.
Nguyen’s arguments regarding Yollin during prosecution
as “amount[ing] to disclaimer of the slow-varying signals
addressed by Yollin.” Id. at *8. In particular, the court
found Mr. Nguyen’s assertions “to be a clear expression by
Mr. Nguyen that if a sensor produces signals at the fre-
quency of those contemplated by Yollin, those frequencies
do not pose a collision problem when combined with slow-
varying button data and are therefore distinct from ‘fast-
varying’ signals addressed by the ’730 patent.” Id. Based
on this finding, the court determined that a person of ordi-
nary skill in the art “would understand the upper bound of
‘slow-varying’ signals covered by Yollin to set the lower
bound of ‘fast-varying’ signals covered by the ’730 patent.”
Id. The court then credited Dr. Chizeck’s testimony iden-
tifying “500 Hz as the upper limit of slow-varying signals
covered by Yollin.” Id. at *9–10.
The district court rejected Genuine’s argument that
Mr. Nguyen had only distinguished Yollin on the grounds
that its signals were slow-varying rather than fast-varying,
and that Mr. Nguyen accordingly should only be deemed to
have disclaimed slow-varying signals below the audio fre-
quency spectrum. Id. at *9. The court cited Andersen Corp.
v. Fiber Composites, LLC, 474 F.3d 1361, 1374 (Fed. Cir.
2007), for the proposition that “an applicant’s argument
that a prior art reference is distinguishable on a particular
ground can serve as a disclaimer of claim scope even if the
applicant distinguishes the reference on other grounds as
well.” Id. “Accordingly,” the district court explained, “even
though Mr. Nguyen distinguished Yollin on the basis that
the ’730 patent addressed ‘audio or higher frequencies,’ this
distinction does not negate his additional statements
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10 GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD.
expressly disavowing as ‘slow-varying’ the range of fre-
quencies addressed by Yollin.” Id. The court also stated
that Genuine had not adequately rebutted Dr. Chizeck’s
analysis and opinion regarding the 500 Hz threshold. Id.
Based on its claim construction of “input signal,” the dis-
trict court granted summary judgment of non-infringement
in favor of Nintendo. Id. at *10–14.
Genuine appealed. We have jurisdiction under
28 U.S.C. § 1295(a)(1).
STANDARD OF REVIEW
We review a district court’s grant of summary judg-
ment under the standard applied in the regional circuit, in
this case the Ninth Circuit. Neville v. Found. Constructors,
Inc., 972 F.3d 1350, 1355 (Fed. Cir. 2020). The Ninth Cir-
cuit reviews a grant of summary judgment de novo. Id. (ci-
tation omitted). Summary judgment is proper only when
the court determines that “no reasonable jury could have
found infringement on the undisputed facts or when all
reasonable factual inferences are drawn in favor of the pa-
tentee.” Netword, LLC v. Centraal Corp., 242 F.3d 1347,
1353 (Fed. Cir. 2001) (first citing Fed. R. Civ. P. 56(c); and
then citing Anderson v. Liberty Lobby, Inc., 477 U.S. 242,
248 (1986)).
We review a district court’s claim construction de novo
and its underlying factual determinations for clear error.
Teva Pharms. USA, Inc. v. Sandoz, Inc., 574 U.S. 318,
326–27 (2015). We review the application of prosecution
disclaimer de novo. Shire Dev., LLC v. Watson Pharms.,
Inc., 787 F.3d 1359, 1365 (Fed. Cir. 2015).
DISCUSSION
I
A
This court has long “emphasized the importance of the
intrinsic evidence in claim construction” while also
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GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD. 11
“authoriz[ing] district courts to rely on extrinsic evidence”
in certain scenarios. Phillips v. AWH Corp., 415 F.3d 1303,
1317 (Fed. Cir. 2005) (en banc). Extrinsic evidence, we
have observed, is generally “less reliable” for claim con-
struction purposes than the intrinsic record for several rea-
sons. Id. at 1318. Extrinsic sources might not have been
written for the purpose of illuminating the scope of the pa-
tent at issue; they might have been written for an audience
different from persons of ordinary skill in the art; they
might suffer from litigation bias; and relatedly, they might
have been selectively plucked from the unbounded uni-
verse of potentially relevant material to advance a liti-
gant’s position. Id. We have therefore cautioned against
“undue reliance” on extrinsic evidence because it “poses the
risk that it will be used to change the meaning of claims in
derogation of the indisputable public records consisting of
the claims, the specification and the prosecution history,
thereby undermining the public notice function of patents.”
Id. at 1319 (citation and quotation marks omitted). In
other words, “[e]xtrinsic evidence is to be used for the
court’s understanding of the patent, not for the purpose of
varying or contradicting the terms of the claims.” Mark-
man v. Westview Instruments, Inc., 52 F.3d 967, 981 (Fed.
Cir. 1995), aff’d, 517 U.S. 370 (1996).
Expert testimony, one type of extrinsic evidence, may
be useful in claim construction “to provide background on
the technology at issue, to explain how an invention works,
to ensure that the court’s understanding of the technical
aspects of the patent is consistent with that of a person of
skill in the art, or to establish that a particular term in the
patent or the prior art has a particular meaning in the per-
tinent field.” Phillips, 415 F.3d at 1318 (citations omitted).
However, expert testimony may not be used to diverge sig-
nificantly from the intrinsic record. See, e.g., id. (“[A] court
should discount any expert testimony that is clearly at odds
with the claim construction mandated by the claims them-
selves, the written description, and the prosecution history,
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12 GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD.
in other words, with the written record of the patent.” (ci-
tation and quotation marks omitted)); see also Vitronics
Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1584 (Fed. Cir.
1996) (“[E]xpert testimony . . . may not be used to vary or
contradict the claim language. Nor may it contradict the
import of other parts of the specification.” (citation omit-
ted)); Aqua-Aerobic Sys., Inc. v. Aerators Inc., 211 F.3d
1241, 1245 (Fed. Cir. 2000) (stating that expert testimony
“may not correct errors or erase limitations or otherwise
diverge from the description of the invention as contained
in the patent documents”); Omega Eng’g, Inc, v. Raytek
Corp., 334 F.3d 1314, 1332 (Fed. Cir. 2003) (“Yet, Omega
submits its expert declarations not to shed light on this
field of art, but to rewrite the patent’s specification and ex-
plicitly provide for the laser splitting device, lenses, and
prisms to strike the center of the energy zone. That we
cannot accept.”); U.S. Indus. Chems. v. Carbide & Carbon
Chems. Corp., 315 U.S. 668, 678 (1942) (“It is inadmissible
to enlarge the scope of the original patent by recourse to
expert testimony to the effect that a process described and
claimed in the reissue, different from that described and
claimed in the original patent, is, because equally effica-
cious, in substance that claimed originally.”).
Accordingly, the intrinsic record “must be considered
and where clear must be followed.” See Mantech Env’t
Corp. v. Hudson Env’t Servs., Inc., 152 F.3d 1368, 1373
(Fed. Cir. 1998); see also Vitronics, 90 F.3d at 1584
(“[W]here the patent documents are unambiguous, expert
testimony regarding the meaning of a claim is entitled to
no weight.”). “Any other rule would be unfair to competi-
tors who must be able to rely on the patent documents
themselves, without consideration of expert opinion that
then does not even exist, in ascertaining the scope of a pa-
tentee’s right to exclude.” Vitronics, 90 F.3d at 1584. Reli-
ance on expert testimony regarding the claim
interpretation is thus permissible where the testimony is
“consistent with [the interpretation] required by the
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GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD. 13
intrinsic evidence.” Goldenberg v. Cytogen, Inc., 373 F.3d
1158, 1166 (Fed. Cir. 2004).
B
The doctrine of prosecution disclaimer “preclud[es] pa-
tentees from recapturing through claim interpretation spe-
cific meanings disclaimed during prosecution.” Omega,
334 F.3d at 1323. “As a basic principle of claim interpreta-
tion, prosecution disclaimer promotes the public notice
function of the intrinsic evidence and protects the public’s
reliance on definitive statements made during prosecu-
tion.” Id. at 1324. For a statement during prosecution to
qualify as a disavowal of claim scope, it must be “so clear
as to show reasonable clarity and deliberateness,” and “so
unmistakable as to be unambiguous evidence of dis-
claimer.” Id. at 1325 (citations omitted); see also Tech.
Props. Ltd. LLC v. Huawei Techs. Co., 849 F.3d 1349, 1358
(Fed. Cir. 2017) (“The patentee’s disclaimer may not have
been necessary, but its statements made to overcome
Magar were clear and unmistakable.”). If the challenged
statements are ambiguous or amenable to multiple reason-
able interpretations, prosecution disclaimer is not estab-
lished. See Tech. Props., 849 F.3d at 1358 (citing Mass.
Inst. of Tech. v. Shire Pharms., Inc., 839 F.3d 1111, 1119
(Fed. Cir. 2016)). “The party seeking to invoke prosecution
history disclaimer bears the burden of proving the exist-
ence of a clear and unmistakable disclaimer that would
have been evident to one skilled in the art.” Shire, 839 F.3d
at 1119 (citation and quotation marks omitted).
II
The parties agree that Mr. Nguyen disavowed claim
scope during prosecution of the ’730 patent in distinguish-
ing his claimed inventions from the Yollin reference. Ap-
pellant’s Br. 34; Appellee’s Br. 26. The parties dispute
whether he disavowed claim scope beyond signals below
the audio frequency spectrum.
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14 GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD.
Genuine contends that the prosecution history clearly
shows that Mr. Nguyen disclaimed “slow-varying” signals
from the full scope of the term “input signal.” Appel-
lant’s Br. 35. According to Genuine, Mr. Nguyen estab-
lished a clear demarcation between Yollin’s low-frequency
signals and the signals “of audio or higher frequency” used
in his inventions. Id. Genuine further argues that the dis-
trict court erred by finding disavowal of additional claim
scope where the record shows no such disavowal. Id. at 38.
According to Genuine, neither the intrinsic record nor
Yollin ever discussed signal frequency in a manner that
would allow a person of ordinary skill in the art to draw
any bright line in claim scope based on frequency, let alone
a bright line at 500 Hz. Id. Genuine also contends that the
district court erroneously relied on testimony by Nin-
tendo’s expert, Dr. Chizeck, that a person of ordinary skill
in the art would have understood Mr. Nguyen’s assertions
as a disavowal of all signals of frequencies up to 500 Hz.
Id. at 44. Genuine points out that Dr. Chizeck’s testimony
had no support in the intrinsic record, but rather was based
solely on other extrinsic evidence purporting to describe
various signals’ frequency ranges. Id. at 44–45. We agree
with Genuine.
We conclude that the only disavowal of claim scope that
is clear and unmistakable in the record before us is Mr.
Nguyen’s disavowal of signals below the audio frequency
spectrum. Omega, 334 F.3d at 1325–26 (prosecution his-
tory disclaimer must be clear and unmistakable). Mr. Ngu-
yen repeatedly distinguished his inventions from Yollin on
the grounds that Yollin taught “slow-varying signals”
whereas his inventions involved “audio or higher fre-
quency” signals. See J.A. 1784–85. The examiner’s ac-
ceptance of that distinction and resulting decision to allow
the claims suggest that Mr. Nguyen and the examiner
reached an understanding on that point. To the extent Mr.
Nguyen’s statements may implicate other claim scope—
such as signals of frequency up to 500 Hz—the record does
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GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD. 15
not rise to the level of establishing a “clear and unmistak-
able” disavowal. Tech. Props., 849 F.3d at 1358 (disclaimer
is not established where statements are ambiguous or ame-
nable to multiple reasonable interpretations).
Regarding the 500 Hz threshold, the district court
erred by relying on expert testimony to limit the claim
scope in a manner not contemplated by the intrinsic record.
The district court credited Dr. Chizeck’s testimony that the
signals disclosed in Yollin would have had frequencies up
to 500 Hz. Genuine, 2020 WL 4366163, at *9 (“Based on
Dr. Chizeck’s testimony, which identifies 500 Hz as the up-
per limit of slow-varying signals covered by Yollin, Nin-
tendo proposes that the Court construe ‘input signal’ as
frequencies greater than 500 Hz.”). As Genuine points out,
the 500 Hz frequency threshold has no basis anywhere in
the intrinsic record; instead, Dr. Chizeck divines that
threshold from another extrinsic reference he calls “Yuce
et al.” The district court, however, did not assess the Yuce
reference in its decision. Neither a full citation for that ref-
erence nor the reference itself appears in the record before
us. Nintendo does not make any mention of that reference,
let alone attempt to defend its soundness as a basis for Dr.
Chizeck’s testimony. We are left, therefore, with the con-
clusion that the district court relied on extrinsic evidence
upon extrinsic evidence to draw a bright line in claim scope
not suggested anywhere in the intrinsic record. Such evi-
dence cannot properly overcome the clarity with which Mr.
Nguyen only disavowed signals below the audio frequency
spectrum. Mantech, 152 F.3d at 1373; Vitronics, 90 F.3d at
1584; Goldenberg, 373 F.3d at 1166.
In view of our conclusion above that Mr. Nguyen only
disavowed signals below the audio spectrum, the district
court also erred to the extent it found that Mr. Nguyen dis-
avowed signals based on their content or nature—namely,
“signals generated from positional change information,
user selection information, physiological response infor-
mation, and other slow-varying information.” Genuine,
Case: 20-2167 Document: 40 Page: 16 Filed: 04/01/2022
16 GENUINE ENABLING TECHNOLOGY v. NINTENDO CO., LTD.
2020 WL 4366163, at *10–11. Mr. Nguyen’s assertions dis-
tinguishing his inventions from Yollin do not clearly and
unmistakably demonstrate any such disclaimer. The ex-
aminer cited Yollin’s teaching of “input information re-
ceived from motion translation unit 102, user selection unit
104 and physiological response sensor(s) 106” as disclosing
the “input signal” limitation. J.A. 1768 (citing Yollin at
col. 5 ll. 16–18). In response, Mr. Nguyen distinguished
that teaching on the ground that those signals fell below
the audio spectrum. See J.A. 1784–85. The record does not
support finding a separate and distinct disclaimer of claim
scope relating to the particular type or content of signal.
Omega, 334 F.3d at 1325–26; Tech. Props., 849 F.3d at
1357–58.
For the above reasons, we conclude that the district
court erred in construing “input signal,” and we construe
that term to mean “a signal having an audio or higher fre-
quency.”
CONCLUSION
We hold that the district court erred in construing the
term “input signal.” In particular, the district court erred
in finding that Mr. Nguyen disclaimed subject matter other
than signals below the audio frequency spectrum during
prosecution, and it further erred in relying on extrinsic ev-
idence to limit the claim scope to signals above 500 Hz. We
therefore conclude that the proper construction of “input
signal” is “a signal having an audio or higher frequency.”
Accordingly, we reverse the district court’s grant of sum-
mary judgment of non-infringement and remand for fur-
ther proceedings consistent with this opinion.
REVERSED AND REMANDED
COSTS
No costs.
Genuine Enabling Technology v. Nintendo Co., Ltd.
Combined Opinion