Alivecor, Inc. v. Apple Inc.

United States Court of Appeals
for the Federal Circuit
______________________
ALIVECOR, INC.,
Appellant
v.
APPLE INC.,
Appellee
______________________
2023-1512, 2023-1513, 2023-1514
______________________
Appeals from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in Nos. IPR2021-
00970, IPR2021-00971, IPR2021-00972.
______________________
Decided: March 7, 2025
______________________
SEAN S. PAK, Quinn Emanuel Urquhart & Sullivan,
LLP, San Francisco, CA, argued for appellant. Also repre-
sented by WILLIAM A DAMS, New York, NY.
MARK S. DAVIES, White & Case LLP, Washington, DC,
argued for appellee. Also represented by MICHAEL ARI
A MON, Fish & Richardson P.C., San Diego, CA; R UFFIN B.
C ORDELL, WALTER KARL RENNER , Washington, DC;
B ENJAMIN E LACQUA , Houston, TX; MELANIE L. B OSTWICK,
A BIGAIL C OLELLA , ZACHARY HENNESSEE , Orrick, Herring-
ton & Sutcliffe LLP, Washington, DC; E. J OSHUA
R OSENKRANZ , New York, NY.
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ALIVECOR, INC. v. APPLE INC. 2
______________________
Before HUGHES, L INN , and STARK, Circuit Judges.
STARK, Circuit Judge.
Patent owner AliveCor, Inc. (“AliveCor”) appeals from
three final written decisions of the Patent Trial and Appeal
Board (“Board”) in related inter partes reviews (“IPRs”)
that found all claims of its three patents, U.S. Patent Nos.
9,572,499 (the “’499 patent”), 10,595,731 (the “’731 pa-
tent”), and 10,638,941 (the “’941 patent”) (collectively, the
“Challenged Patents”) unpatentable over certain asserted
prior art. AliveCor challenges the Board’s obviousness
findings and argues that the inter partes review petitioner,
Apple Inc. (“Apple”), violated its discovery obligations. Be-
cause the Board’s obviousness conclusion is supported by
substantial evidence and AliveCor forfeited its discovery
challenge, we affirm.
I
A
The Challenged Patents belong to a family of patents
related to systems and methods for measuring and analyz-
ing physiological data to detect cardiac arrhythmias.1 The
’499 patent and ’731 patents share a common specification
and describe “a method for monitoring a subject to deter-
mine when to record an electrocardiogram (ECG).” ’499 pa-
tent 23:12-14.2 The ’941 patent has a different
1 “Arrhythmia is a cardiac condition in which the
electrical activity of the heart is irregular . . . [and] can
cause cardiac arrest.” ’499 patent 1:31-34.
2 For simplicity, all further references to the written
description of the Challenged Patents will be to the ’499
patent, unless otherwise noted.
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ALIVECOR, INC. v. APPLE INC. 3
specification and describes a wearable device designed to
predict the occurrence of arrhythmias.
An embodiment of the Challenged Patents involves the
use of a smart watch configured with a heart rate monitor
such as “an optical sensor to detect the fluctuation of blood
flow,” i.e., a photoplethysmography (“PPG”) sensor, which
uses light to measure volume changes of circulating blood.
’499 patent 25:13-16. As a user wears the smart watch, the
PPG sensor continuously transmits heart rate information
to a smartphone, which then “analyze[s] the heart rate in-
formation” for irregularities. Id. at 23:16-20. “[W]hen an
irregularity is determined,” the user is notified that an
electrocardiogram (“ECG”) “should be recorded.” Id. at
23:20-22. The user may then use a second sensor, specifi-
cally “a hand-held [ECG] sensor,” id. at 4:48-49, to record
“electrical activity of the heart based on depolarization and
repolarization of the atria and ventricles,” J.A. 119 (inter-
nal quotation marks omitted), and, with this additional
data, diagnose if the user has a cardiac arrythmia. The
user may also use the ECG sensor “to record ECGs that can
then be saved and/or transmitted for analysis.” Id. at
23:24-26.
This process is illustrated in Figure 10, reproduced be-
low.
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ALIVECOR, INC. v. APPLE INC. 4
The same process is the basis of representative claim 1 of
the ’499 patent, which recites:
A method of determining a presence of an ar-
rhythmia of a first user, said method comprising
sensing a heart rate of said first user with
a heart rate sensor coupled to said first user;
transmitting said heart rate of said first
user to a mobile computing device, wherein
said mobile computing device is configured to
sense an electrocardiogram;
determining, using said mobile computing
device, a heart rate variability of said first user
based on said heart rate of said first user;
sensing an activity level of said first user
with a motion sensor;
comparing, using said mobile computing
device, said heart rate variability of said first
user to said activity level of said first user; and
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ALIVECOR, INC. v. APPLE INC. 5
alerting said first user to sense an electro-
cardiogram of said first user, using said mobile
computing device, in response to an irregular-
ity in said heart rate variability of said first
user.
Id. at 26:20-39.
The appeal before us principally focuses on two fea-
tures of the claims of the Challenged Patents: the use of
machine learning to detect arrhythmias, and the step of
confirming the presence of arrhythmias. The ’499 and ’731
patents broadly contemplate the use of machine learning
to detect arrhythmias from ECG data. They reference mul-
tiple machine learning operations spanning a diverse
range of complexity, ranging from simple operations such
as “ranking,” “classifying,” “labelling,” “predicting,” and/or
“clustering” data, to more complex operations like “random
forest, association rule learning, artificial neural network,
inductive logic programming, [and] support vector ma-
chines.” Id. at 9:52-64. The use of machine learning is re-
cited in dependent claims 7-9 and 17-19 of the ’499 patent
and dependent claims 3, 5, 6, 19, and 21-22 of the ’731 pa-
tent.
The dependent claims requiring machine learning all
describe the use of machine learning at a high level of gen-
erality. For example, representative claim 7 of the ’499 pa-
tent recites:
The method of claim 1, further comprising deter-
mining a presence of said arrhythmia using a ma-
chine learning algorithm.
Id. at 26:54-56. Other dependent claims recite a machine
learning algorithm for detecting arrhythmia using inputs
of PPG data, heart rate and heart rate variability (“HRV”),
or motion sensor data. No claim requires a specific type of
machine learning algorithm.
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ALIVECOR, INC. v. APPLE INC. 6
The second feature pertinent to this appeal is the “con-
firming” step recited in claim 1 of each of the ’731 and ’941
patents, reproduced below, respectively:
A smart watch to detect the presence of an arrhyth-
mia of a user, comprising:
a processing device;
a photoplethysmography (“PPG”) sensor
operatively coupled to the processing device;
an ECG sensor, comprising two or more
ECG electrodes, the ECG sensor operatively
coupled to the processing device;
a display operatively coupled to the pro-
cessing device; and
a memory, operatively coupled to the pro-
cessing device, the memory having instructions
stored thereon that, when executed by the pro-
cessing device, cause the processing device to:
receive PPG data from the PPG sensor;
detect, based on the PPG data, the presence
of an arrhythmia;
receive ECG data from the ECG sensor;
and
confirm the presence of the arrhythmia
based on the ECG data.
’731 patent 26:27-46 (emphasis added).
A method of cardiac monitoring, comprising:
sensing an activity level of a user with a
first sensor on a smartwatch worn by the user;
when the activity level is resting, sensing a
heart rate parameter of the user with a second
sensor on the smartwatch;
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ALIVECOR, INC. v. APPLE INC. 7
determining, by a processing device, that a
discordance is present between the activity
level value and the heart rate parameter;
based on the presence of the discordance,
indicating to the user, using the smartwatch, a
possibility of an arrhythmia being present; and
receiving electric signals of the user from
an electrocardiogram sensor (“ECG”) on the
smartwatch to confirm a presence of the ar-
rhythmia, wherein the ECG sensor comprises a
first electrode and a second electrode.
’941 patent at 17:2-17 (emphasis added). Other than in the
claims, the specifications of the ’731 and ’941 patents do
not reference or describe the “confirming” step.
B
Apple presented multiple obviousness grounds in its
petition, contending (as pertinent to this appeal) that the
machine learning and confirmation limitations of the Chal-
lenged Patents were rendered obvious by the teachings of
certain combinations of prior art references. Apple relied
on two references in its challenge to the machine learning
claims: Hu 1997,3 which Apple contended disclosed the ma-
chine learning limitations of the claims of the ’499 patent,
and Li 2012,4 which purportedly teach the machine learn-
ing limitations of the ’731 patent’s claims.
3 Yu Hen Hu et al., A Patient-Adaptable ECG Beat
Classifier Using a Mixture of Experts Approach, 44(9) IEEE
Transactions on Biomed. Eng’g 891 (1997).
4 Qiao Li & Gari D. Clifford, Signal Quality and Data
Fusion for False Alarm Reduction in the Intensive Care
Unit, 45(6) J. Electrocardiology 596 (2012).
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ALIVECOR, INC. v. APPLE INC. 8
Hu 1997 describes the creation of a computerized clas-
sification algorithm for detecting and classifying ECG sig-
nals. That algorithm is “developed based on brief, patient-
specific ECG data . . . combined with a global classifier,
which is tuned to a large ECG database of many patients,
to form a MOE [i.e., mixture-of-experts, which is a type of
machine learning algorithm] classifier structure.” J.A.
4801. Hu 1997 adds that use of its algorithm will “gain
significant performance enhancement at low cost,” and fur-
ther touts that its teachings “can be easily adapted to other
automated patient monitoring algorithms and eventually
support decentralized remote patient-monitoring systems.”
J.A. 4805; J.A. 4809.
Li 2012 describes the use of machine learning to reduce
the frequency of false alarms which indicate, incorrectly,
the presence of arrhythmia conditions in intensive care
unit patients. Li 2012 discloses “a novel framework for
[false alarm] reduction using a machine learning approach
to combine up to 114 signal quality and physiological fea-
tures extracted from the [ECG], [PPG], and optionally the
arterial blood pressure waveform.” J.A. 3873.
For the “confirming” step of the ’731 and ’941 patents,
Apple relied on PCT Patent Application No. 2012/140559
to Shmueli (“Shmueli”). Shmueli teaches “a combined oxi-
metry and [ECG] measuring system and method in which
the oximetry measurement is performed continuously
and/or repeatedly, and the ECG measurement is triggered
upon detection of an intermittent irregular heart-related
event.” J.A. 3825. Shmueli teaches a wrist-mounted heart
monitoring device equipped with both an “oximetry (SpO2 )
measuring unit,” i.e., a PPG sensor,5 and “an ECG measur-
ing unit.” J.A. 3826. Shmueli explains how software may
be used “to detect various irregularities of the heart
5 It is undisputed that Shmueli uses the terms “oxi-
metry,” “SpO2,” and “PPG” interchangeably. J.A. 3824.
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ALIVECOR, INC. v. APPLE INC. 9
condition” by comparing measured PPG data with stored
“heart-irregularity detection parameters.” J.A. 3829. Once
an irregularity is detected, the software notifies the user
and “initiates ECG measurement.” Id. The software then
“proceeds to element 50 to search for correlations between
the [PPG] signal and the ECG signal to produce new detec-
tion parameters, or modify existing detection parameters,
so as to enhance the detection algorithms of the irregular
heart conditions.” J.A. 3830. Modifying the detection pa-
rameters in this manner (element 50) “can be executed in
real-time []together with elements” 37 (measuring PPG),
47 (notifying user to perform an ECG measurement), and
49 (recording PPG and ECG measurements). Id. The pro-
cess continues in this manner until “the software program
detects that a condition for stopping the ECG measure-
ment is met (element 51),” such as determining that the
irregular heart condition has stopped. Id.
The process described above is shown as a flow chart in
Shmueli’s Figure 7, reproduced below.
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ALIVECOR, INC. v. APPLE INC. 10
J.A. 3843. Apple argued that a person of ordinary skill in
the art would have understood that the software at ele-
ments 38, 39, and 50 “causes the processing device to con-
firm the presence of the arrhythmia based on the ECG
data, by searching for correlations between the PPG and
ECG data, modifying detection parameters, and confirming
the presence of arrhythmia.” J.A. 92.
In its Final Written Decisions, the Board agreed with
Apple that Shmueli in combination with Hu 1997 rendered
obvious the machine learning claims of the ’499 patent,
while Shmueli in combination with Li 2012 rendered obvi-
ous the machine learning claims of the ’731 patent. In
reaching its conclusion with respect to the ’499 patent, the
Board rejected AliveCor’s contention that Hu 1997 “only
shows machine learning in contexts other than arrythmia
detection,” J.A. 45, because “although Hu 1997 exemplifies
the detection of arrhythmia using ECG data . . . the source
of the heart rate parameters (e.g., ECG or SpO2 /PPG)
would not have deterred a [person of ordinary skill in the
art] from applying machine learning to them given the
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ALIVECOR, INC. v. APPLE INC. 11
advantages of the approach in enhancing performance and
detection accuracy,” J.A. 46 (internal quotation marks
omitted). With respect to the machine learning claims of
the ’731 patent, the Board agreed with Apple that “after an
ECG is measured, it would have been obvious to confirm
arrhythmia detection using a machine learning algorithm
based on the PPG data, motion sensor data, and/or ECG
data.” J.A. 111. The Board recognized that Li 2012’s ma-
chine learning algorithm used multiple data inputs and
found that “[n]one of the claims challenged . . . preclude
ECG data (or any other data used in Li 2012) from also be-
ing input into the algorithm.” J.A. 109. The Board also
looked to the general state of the art, finding that at the
pertinent date “those of ordinary skill in the art had . . .
both interest and success in adapting machine learning to
various biomedical applications.” J.A. 110.
As for the “confirming” limitation, found in the claims
of the ’731 and ’941 patents, requiring the confirmation of
arrythmias using ECG measurements, the Board credited
the testimony of Apple’s expert, Dr. Bernard Chaitman,
and found that Shmueli’s teachings would have led “one of
ordinary skill in the art [to] have understood that deter-
mining whether ‘[t]he irregular heart condition has
stopped,’ and notifying the user,” both of which Shmueli
does, “requires, as a predicate, that the software program
confirm the presence of arrhythmia using the ECG data.”
J.A. 94-95; see also J.A. 3461-64. Thus, the Board held that
all claims of the Challenged Patents were unpatentable as
obvious.
C
During the IPR proceedings, the validity of the Chal-
lenged Patents was also being litigated in parallel proceed-
ings before the International Trade Commission (“ITC”).
AliveCor filed a complaint in the ITC on April 20, 2021, al-
leging that Apple was importing or selling products infring-
ing claims of the three Challenged Patents. See Certain
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ALIVECOR, INC. v. APPLE INC. 12
Wearable Electronic Devices, Inv. No. 337-TA-1266, 2022
WL 2981155, at *3 (U.S.I.T.C. July 27, 2022) (“ITC Initial
Decision”). The ITC instituted an investigation on May 26,
2021, and a few weeks later – on June 9, 2021 – Apple filed
its IPR petitions at the Board.
The Board instituted the IPRs on December 8, 2021.
Shortly thereafter, AliveCor’s counsel contacted Apple’s
counsel and requested Apple’s consent to introduce in the
IPR proceedings evidence of secondary considerations that
had been produced by Apple in the ITC investigation. The
following email exchange took place between counsel:
[AliveCor:]
Apple has produced in the ITC relevant, non-public
documents regarding secondary considerations of
non-obviousness. . . . Please let us know if you will
consent to the use of these documents in the IPR
proceedings. If not, let us know your availability
for a conference with the Board to request briefing
to allow discovery requests related to secondary in-
dicia.
[Apple:]
Your request to utilize these documents in the IPRs
or utilize them as the basis for a discovery request
in the IPRs is a violation of at least paragraph 4 of
the ITC protective order.
[AliveCor:]
[W]e still have not heard back from Apple as to
whether it opposes our request to use the below-
identified documents in the IPR proceeding. . . . If
Apple does oppose our request, we intend to seek
permission from the Board to serve targeted
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ALIVECOR, INC. v. APPLE INC. 13
discovery requests on the issue of secondary consid-
erations.
[Apple:]
As mentioned below, AliveCor’s use of these docu-
ments in the IPRs or use of them as the basis for a
discovery request in the IPRs would be a violation
of the ITC protective order. . . . AliveCor’s request
to the PTAB based on its knowledge of allegedly
relevant information produced under the ITC pro-
tective order is improper. . . . Apple does not grant
AliveCor permission to disclose these documents to
the PTAB in the IPRs. Unless AliveCor has “an or-
der by the Commission or the Administrative Law
Judge,” disclosure of these documents to the
[Board], as well as their use for discovery requests
in the IPRs, would be a violation of the ITC protec-
tive order.
J.A. 8814-15 (emphasis added). Neither party apprised the
Board of this discovery dispute at any point during IPR
proceedings. Nor did AliveCor ever ask the ITC to grant it
permission to use the materials produced by Apple in the
ITC investigation in the IPRs.
On June 27, 2022, an ITC administrative law judge
(“ALJ”) issued an Initial Decision rejecting Apple’s obvious-
ness contentions and, therefore, upholding the validity of
various claims of the Challenged Patents. In reaching its
conclusion, the ALJ found that AliveCor had presented sec-
ondary consideration evidence sufficient to rebut Apple’s
“strong” prima facie showing of obviousness. ITC Initial
Decision, 2022 WL 2981155 at *66. Specifically, the ALJ
noted that “[t]he nature and volume of industry praise is
unusual, particularly the praise published in a respected
medical journal, and although the evidence of copying is
not especially impressive, some degree of commercial
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ALIVECOR, INC. v. APPLE INC. 14
success is evidenced from the [AliveCor product] sales data
and the testimony of [AliveCor’s] chief financial officer.”
Id.
By the time the consolidated IPR oral hearing was held
on September 14, 2022, the ALJ’s Initial Decision had been
publicly available for nearly three months. Nevertheless,
AliveCor made no effort to inform the Board of the ALJ’s
findings with respect to the evidence of copying that had
been presented in the ITC, and it did not ask the Board to
order Apple to produce that same evidence as discovery in
the IPRs.
AliveCor timely appealed. We have jurisdiction under
28 U.S.C. § 1295(a)(4)(A).
II
A patent is invalid for obviousness “if the differences
between the claimed invention and the prior art . . . would
have been obvious before the effective filing date of the
claimed invention to a person having ordinary skill in the
art to which the claimed invention pertains.” 35 U.S.C.
§ 103. “The ultimate question of obviousness is a legal
question that we review de novo with underlying factual
findings that we review for substantial evidence.” Roku,
Inc. v. Universal Elecs., Inc., 63 F.4th 1319, 1324 (Fed. Cir.
2023). Those underlying factual findings include
“[w]hether a person of ordinary skill in the art would have
been motivated to modify or combine teachings in the prior
art, and whether he would have had a reasonable expecta-
tion of success.” OSI Pharms., LLC, v. Apotex, Inc., 939
F.3d 1375, 1382 (Fed. Cir. 2019) (internal citation omitted).
Substantial evidence is “such relevant evidence as a rea-
sonable mind might accept as adequate to support a con-
clusion.” Consol. Edison Co. of N.Y. v. N.L.R.B., 305 U.S.
197, 229 (1938).
We also review the Board’s decision for compliance
with the Administrative Procedure Act (“APA”), 5
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ALIVECOR, INC. v. APPLE INC. 15
U.S.C. § 550 et seq. Under the APA, we must “hold unlaw-
ful and set aside agency action, findings, and conclusions
found to be . . . arbitrary, capricious, an abuse of discretion,
or otherwise not in accordance with law,” made “without
observance of procedure required by law,” or “unsupported
by substantial evidence.” 5 U.S.C. § 706(2). In making
these determinations, “due account shall be taken of the
rule of prejudicial error.” Id.; see also ZyXEL Commc’ns
Corp. v. UNM Rainforest Innovations, 107 F.4th 1368,
1382 (Fed. Cir. 2024) (describing § 706 as “harmless error
rule”).
III
AliveCor raises three main issues on appeal. First,
AliveCor argues that the Board erred in finding the ma-
chine learning claims were obvious based on Hu 1997 or Li
2012 in combination with Shmueli. Second, AliveCor chal-
lenges the Board’s finding that Shmueli rendered the “con-
firming” step obvious. Finally, AliveCor contends that
Apple violated its discovery obligations by failing to pro-
duce secondary consideration evidence from the parallel
ITC proceeding. We address, and reject, each of these ar-
guments in turn.
A
AliveCor challenges the Board’s findings that Hu 1997
and Li 2012, in combination with Shmueli, render obvious
the machine learning steps recited in dependent claims of
the ’499 and ’731 patents. We are not persuaded. The
Board’s findings are supported by substantial evidence.
The Board had substantial evidence, including the tes-
timony of Apple’s expert, Dr. Chaitman, for its finding that
the teachings of Shmueli combined with Hu 1997 or Li
2012 would have motivated one of ordinary skill in the art
to use a machine learning algorithm to detect arrhythmias
in the manner claimed. It is undisputed that Hu 1997 and
Li 2012 each teach the use of machine learning to assess
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ALIVECOR, INC. v. APPLE INC. 16
ECG data. See Open. Br. at 16 (“Hu 1997 does teach ma-
chine learning . . . .”); id. at 39 (“Li 2012 teaches using ma-
chine learning on a dataset with multiple data sources,
including ECG, ABP, and PPG.”) (internal emphasis omit-
ted). To restrict each reference’s teachings to the particu-
lar way it implements machine learning, as AliveCor
insists we should do, would improperly fail to read these
references for all that they disclose. See In re Mouttet, 686
F.3d 1322, 1331 (Fed. Cir. 2012) (“A reference may be read
for all that it teaches, including uses beyond its primary
purpose.”). AliveCor’s approach also conflicts with the re-
ality that the skilled artisan is not an automaton, so we
must “take account of the inferences and creative steps
that a person of ordinary skill in the art would employ.”
KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007).
There was, thus, nothing improper in the Board’s determi-
nation that such an artisan would have found it obvious to
use machine learning in connection with PPG data, even if
this precise use is not expressly disclosed in either Hu 1997
or Li 2012.
Moreover, the Challenged Patents’ machine learning
claims, accorded their plain and ordinary meaning in light
of the specification, do not require any specific type of ma-
chine learning algorithm or a precise method for inputting
and analyzing data to detect arrhythmias. Hence, Apple’s
burden could be, and was, satisfied by substantial evidence
that a person of ordinary skill in the art would have found
it obvious to use machine learning, generally, in the con-
text of PPG and ECG data to detect cardia arrhythmia. Hu
1997’s and Li 2012’s descriptions of machine learning algo-
rithms provide sufficient evidentiary support for the
Board’s obviousness findings, findings that were made at
the same level of specificity as the claims.
AliveCor insists that the Board found, at most, that a
person of ordinary skill in the art would have been moti-
vated to use machine learning to “confirm” arrythmia,
which cannot support the Board’s conclusion that the
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ALIVECOR, INC. v. APPLE INC. 17
Challenged Patents’ use of machine learning to “detect” ar-
rhythmia was obvious. We disagree with this characteri-
zation of the Board’s analysis. The Board acknowledged
that “‘confirm’ and ‘confirming’ are discrete requirements
from ‘detect,’” and, with this understanding, found that Li
2012 taught “the use of machine learning to . . . ‘improv[e]
the accuracy of true positive detection.’” J.A. 85, 107 (em-
phasis added). Therefore, the Board did not wrongfully
conflate the detection and confirmation requirements.
We also disagree with AliveCor’s argument that the
Board abused its discretion in crediting Dr. Chaitman’s
testimony. In AliveCor’s view, Dr. Chaitman lacks suffi-
cient expertise in machine learning technology. We disa-
gree. While Dr. Chaitman is not experienced in specific,
complex machine learning algorithms, he is qualified to
opine on the applicability of machine learning generally.
J.A. 25-27, 82-83 (describing Dr. Chaitman as having “ex-
tensive experience working with tools for detecting cardiac
conditions”). Given the nature of the claims, and the fact
that the Board only relied on Dr. Chaitman (in this context)
for the general applicability of machine learning, the Board
concluded that more advanced expertise in computer sci-
ence and machine learning were “not prerequisites for
qualifying a person of ordinary skill in the art.” J.A. 26-27,
84. We discern no error in this holding.
Finally, AliveCor challenges the Board’s reliance on a
statement from Dr. Collin Stultz, Apple’s expert in the ITC,
to the effect that machine learning algorithms were well-
known in the prior art. J.A. 110 (noting Dr. Stultz testi-
mony that “a machine learning algorithm without specifics
is nothing more than generic, functional language”). Even
assuming, without deciding, that Dr. Stultz’s testimony
was irrelevant (because it addressed whether AliveCor’s
claims are directed to patentable subject matter under 35
U.S.C. § 101 and not whether they are obvious under
§ 103), AliveCor has not met its burden of demonstrating
that the Board’s reliance on this testimony prejudiced it.
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ALIVECOR, INC. v. APPLE INC. 18
See In re Watts, 354 F.3d 1362, 1369 (Fed. Cir. 2004) (“[T]he
appellant must not only show the existence of error, but
also show that the error was in fact harmful because it af-
fected the decision below.”). Indeed, AliveCor acknowl-
edges that the Board “did not even rely on Dr. Stultz’s
testimony for obviousness” and only cited to the testimony
“in passing.” Open. Br. at 33-34. Even excluding its refer-
ence to Dr. Stultz’s testimony, the Board’s finding that ma-
chine learning was generally well-known was supported by
overwhelming evidence, including the testimony of Alive-
Cor’s expert, Dr. Efimov.
Accordingly, substantial evidence supports the Board’s
determination that the machine learning claims of the ’499
and ’731 patents were obvious over the prior art.
B
Substantial evidence also supports the Board’s finding
that Shmueli teaches the step of confirming arrythmias us-
ing ECG measurements after a potential arrythmia is de-
tected using PPG. Shmueli’s Figure 7 depicts collection of
a patient’s ECG data (element 48) followed by (in element
50) “search[ing] for correlations between the [PPG] signal
and the ECG signal to . . . modify existing detection param-
eters, so as to enhance the detection algorithms of the ir-
regular heart conditions.” J.A. 3829-30; see also J.A. 3843.
Shmueli further explains that this step of searching for cor-
relations can be performed in real-time together with ele-
ment 37, measuring PPG. The Board reasonably read
these portions of Shmueli as teaching a feedback loop in
which collected ECG data is used to update the detection
parameters used to identify irregularities from incoming
PPG data in real time. See J.A. 94 (Board agreeing with
Apple that “Shmueli works as follows: (1) continuously
measuring SpO2 /PPG data; (2) measuring ECG data upon
detecting an irregular heart condition; and (3) correlating
SpO2 /PPG and ECG data to confirm presence of the irreg-
ular heart condition”). The Board also reasonably read
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ALIVECOR, INC. v. APPLE INC. 19
Shmueli as teaching that the SpO2 /PPG measurement and
ECG measurement “are continued and performed in paral-
lel” until the system determines that the irregular heart
condition has stopped. J.A. 94.
The Board found further support for its determination
in Dr. Chaitman’s testimony. Dr. Chaitman opined that a
person of ordinary skill in the art would have understood
that Shmueli’s feedback loop – including element 50
(searching for correlations between PPG and ECG signals),
element 39 (using detection parameters to detect irregular
heart conditions), and element 38 (using PPG data to de-
tect irregular heart conditions) – “causes the processing de-
vice to confirm the presence of the arrhythmia based on the
ECG data, by searching for correlations between the PPG
and ECG data, modifying detection parameters, and con-
firming the presence of arrhythmia.” J.A. 3461-63 ¶¶ 111-
12. The Board also fairly credited Dr. Chaitman’s testi-
mony that one of ordinary skill reading Shmueli “would
have understood that determining whether ‘the irregular
heart condition has stopped’ also requires the software pro-
gram to confirm the presence of arrythmia using the ECG
data.” J.A. 3464 ¶ 113.
AliveCor’s contention that Shmueli confirms arryth-
mias using only PPG – and not, as the claims of the Chal-
lenged Patents do, using ECG – is incorrect. As the Board
recognized, Shmueli states that when an irregular heart
condition is detected, the PPG measurement “preferably
continues,” J.A. 3829 (emphasis added), which the Board
fairly read to indicate that Shmueli teaches embodiments
in which the PPG measurement has not continued, mean-
ing (in such an embodiment) “ECG is the only measure-
ment that can be used to perform the operations described
by Shmueli, including determining whether the irregular
heart condition has stopped,” J.A. 96 (internal quotation
marks omitted).
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ALIVECOR, INC. v. APPLE INC. 20
AliveCor’s characterization of the Board’s findings as
embracing the flawed proposition that searching for corre-
lations is equivalent to confirming arrhythmia based on
ECG data lacks merit. Instead, we read the Board as find-
ing that a skilled artisan would understand Shmueli’s real-
time modification of detection parameters as requiring a
confirmation step. See J.A. 94 (determining that claims
broadly encompass “confirming the presence of arrhythmia
based on new parameters generated from analyzing the
ECG data”); J.A. 95 (finding step of determining whether
irregular heart condition has stopped “requires, as a pred-
icate, that the software program confirm the presence of
arrhythmia using the ECG data”). This is, as we have al-
ready explained, a reasonable reading of Shmueli’s teach-
ings and is supported by substantial evidence, including
Dr. Chaitman’s opinion.
Thus, we conclude that substantial evidence supports
the Board’s findings.
C
Lastly, AliveCor asks us to vacate the Board’s decisions
due to Apple’s failure to comply with what AliveCor char-
acterizes as the self-executing discovery obligations of an
IPR petitioner. Specifically, AliveCor contends that Apple
violated its discovery duties by failing to produce, in the
IPRs, the secondary consideration evidence that the ALJ
had found persuasive in the parallel ITC investigation. We
need not delve deeply into the contours of an IPR litigant’s
discovery obligations because AliveCor forfeited its argu-
ment by failing to raise it with the Board.
“By regulation, the Board has provided for limited
mandatory discovery.” Wi-Fi One, LLC v. Broadcom Corp.,
887 F.3d 1329, 1338 (Fed. Cir. 2018). A petitioner’s “rou-
tine discovery” obligations are set forth in 38 C.F.R.
§ 42.51(b)(1), which requires, among other things, that:
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ALIVECOR, INC. v. APPLE INC. 21
Unless previously served, a party must serve rele-
vant information that is inconsistent with a posi-
tion advanced by the party during the proceeding
concurrent with the filing of the documents or
things that contain[] the inconsistency.
37 C.F.R. § 42.51(b)(1)(iii). AliveCor contends that Apple
produced evidence of secondary considerations in the par-
allel ITC proceeding that supported a finding of nonobvi-
ousness, making such evidence inconsistent with the
position Apple was advocating in the IPRs, which is that
the claims of the Challenged Patents are obvious. This
means, according to AliveCor, that Apple violated its dis-
covery obligations when it failed to produce such evidence
in the IPRs.
We will not address the merits of AliveCor’s contention
because it failed to preserve the issue for appellate review.6
See In re Google Tech. Holdings LLC, 980 F.3d 858, 863
(Fed. Cir. 2020) (“[A] position not presented in the tribunal
under review will not be considered on appeal in the ab-
sence of exceptional circumstances.”). While it is not, of
course, AliveCor’s responsibility to ensure that Apple
meets its own discovery obligations under the Board’s
rules, it is AliveCor’s obligation to present issues to the
Board, and preserve them, if it wants an opportunity to
6 During pendency of this appeal, Apple filed two ci-
tations of Supplemental Authority, one notifying us of two
Final Written Decisions concerning related patents in
which the Board found that secondary consideration evi-
dence did not rebut the petitioner’s prima facie showing of
obviousness, and the other notifying us of the joint volun-
tary dismissal of appeals from those decisions. See ECF
No. 53, 59. AliveCor responded to the first of these filings.
See ECF No. 54. We have considered these filings, but they
have no impact on our decision, given our conclusion that
AliveCor forfeited its discovery issue.
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ALIVECOR, INC. v. APPLE INC. 22
argue them on appeal. As AliveCor concedes, it never
brought the discovery issue to the Board’s attention, a
choice it seeks to excuse by pointing to Apple’s rejection of
AliveCor’s request to raise the issue with the Board. See
Oral Arg. at 11:16-12:01 (AliveCor counsel admitting to not
informing Board of secondary consideration evidence);7
Open. Br. at 59 (“[Apple] affirmatively precluded AliveCor
from even seeking to have these documents introduced be-
fore the Board.”) (emphasis omitted); see also supra I.C.
(setting out email exchange between counsel). But Apple’s
posture did not relieve AliveCor of its obligation to present
its concern to the Board and seek relief there rather than
raising these matters with us, for the first time, on appeal.
Nor does this case present exceptional circumstances
that might justify excusing AliveCor’s forfeiture. AliveCor
could have told the Board it believed Apple was violating
its discovery obligations, or requested that the Board allow
AliveCor to introduce evidence from the ITC in the IPR pro-
ceedings. At the very least, AliveCor could have directed
the Board to the portion of the publicly-available ITC ALJ
Initial Decision showing that the ITC was persuaded by
secondary consideration evidence that Apple was not per-
mitting the Board to consider. See generally ITC Initial
Decision, 2022 WL 2981155 at *66, *86-87, *104-05.8
7 Available at https://oralarguments.cafc.uscourts.
gov/default.aspx?fl=23-1512_07122024.mp3.
8 At oral argument, AliveCor suggested it could not
have put the ITC Initial Decision in the record because it
was released after briefing was completed, and the Board
requires all arguments to be made in written submissions.
Oral Arg. at 11:00-12:01. The Board, however, permits par-
ties to file a motion to submit supplemental information
when it is “relevant to a claim for which the trial has been
instituted.” 37 C.F.R. § 42.123. Had AliveCor filed such a
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ALIVECOR, INC. v. APPLE INC. 23
Having done none of these things, or anything else to ap-
prise the Board of the issue, we cannot find exceptional cir-
cumstances that would warrant excusing AliveCor’s
forfeiture.9
IV
We have considered AliveCor’s remaining arguments
and find them unpersuasive. For the foregoing reasons, we
affirm.
AFFIRMED
motion, either it would have been permitted to supplement
the record (if the motion was granted) or it would have pre-
served the issue for appeal (if the motion was denied).
9 AliveCor asserts it should be excused from not rais-
ing discovery issues with the Board because it was defer-
ring to Apple’s warnings that doing so would violate the
ITC protective order, potentially leading to adverse conse-
quences for AliveCor at the ITC. See J.A. 8815. Navigating
the competing constraints of parallel proceedings may, no
doubt, present challenges, and our holding today should
not be read as condoning (or, for that matter, faulting) Ap-
ple’s tactics.
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