Siemens Medical Solutions USA, Inc.

Patent Trials and Appeals Board

Aug 21, 2020

2020001171 (P.T.A.B. Aug. 21, 2020)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
14/549,670 11/21/2014 Hongxuan Zhang 2014P18411US 2983
28524 7590 08/21/2020
SIEMENS CORPORATION
IP Dept - Mail Code INT-244
3850 Quadrangle Blvd
Orlando, FL 32817
EXAMINER
KINGSLEY, SARAH R
ART UNIT PAPER NUMBER
3791
NOTIFICATION DATE DELIVERY MODE
08/21/2020 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
ipdadmin.us@siemens.com
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte HONGXUAN ZHANG

Appeal 2020-001171
Application 14/549,670
Technology Center 3700
____________

Before CHARLES N. GREENHUT, MICHAEL L. HOELTER, and
ANNETTE R. REIMERS, Administrative Patent Judges.

HOELTER, Administrative Patent Judge.

DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 1–8 and 11–19 (i.e., all the claims on
appeal).2 We have jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.

1 We use the word “Appellant” to refer to “applicant” as defined in
37 C.F.R. § 1.42. Appellant identifies the real party in interest as “Siemens
Healthcare GMBH.” Appeal Br. 4.
2 Claims 9 and 10 have been canceled and claim 20 has been withdrawn
from consideration. Final Act. 1 (Office Action Summary); Appeal Br. 4–5.
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CLAIMED SUBJECT MATTER
The disclosed subject matter “relates to systems and methods for
filtering patient signals.” Spec. ¶ 1. Computer-readable medium claim 1
and method claim 6 are independent. Claim 1 is illustrative of the claims on
appeal and is reproduced below.
1. A non-transitory computer readable medium having
embodied thereon computer-executable instructions which,
when executed, cause a computer to perform steps for signal
filtering, the steps comprising:
receiving an electrocardiogram signal, wherein the
electrocardiogram signal includes an electrocardiogram signal
component, noise, a respiration signal component and a blood
pressure signal component;
removing the electrocardiogram signal component from
the electrocardiogram signal to generate a first output signal by
performing an electrocardiogram signature cycle matching
pursuit method;
eliminating the noise from the first output signal to
generate a second output signal by performing sub-bandwidth
filtering of the first output signal;
removing the respiration signal component from the
second output signal to generate a third output signal; and
reconstructing a time-domain blood pressure signal based
on the third output signal by performing inverse fast Fourier
transform (IFFT) on integrated frequency components of the
third output signal.
ISSUES ON APPEAL
Claims 1–8 and 11–193 are rejected under 35 U.S.C. § 112(a) as
failing to comply with the enablement requirement. Final Act. 2.

3 In the header of paragraph 3 of the Final Office Action, the Examiner lists
claims 1–5 and 8 for this rejection; however, in the body of the rejection,
independent claim 6 is discussed (Final Act 2), as is claim 7 (Final Act. 4).
Appellant states, “Appellant is treating claim 6 as being rejected under 35
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Claims 1–8 and 11–19 are rejected under 35 U.S.C. § 101 because
they recite “organiz[ing] information through mathematical correlations
and/or are representative of mathematical relationships or formulas” and
hence, “recite [an] abstract idea.” Final Act. 5. Alternatively, claims 1–8
and 11–19 are rejected under 35 U.S.C. § 101 because they recite steps that
“could be practically performed in the mind,” and hence, also an abstract
idea. Ans. 14.
ANALYSIS
The rejection of claims 1–8 and 11–19
as failing to comply with the enablement requirement
Both independent claims on appeal recite an electrocardiogram
(ECG) signal that includes a blood pressure signal component.4, 5 Appeal
Br. 20, 22 (Claims App). The Examiner finds that “the disclosure does not
describe how a blood pressure signal could be acquired from an
electrophysiological (EP) signal, as these two signals [i.e., EP and blood

U.S.C. § 112(a).” Appeal Br. 9. To be clear, claim 6 is the parent (either
directly or indirectly) of claims 11–19. See Appeal Br. 23–26 (Claims
App.). In the Answer, the Examiner correctly lists claims 1–8 and 11–19 as
being rejected. See Ans. 3. It is thus understood that claims 1–8 and 11–19
are rejected as failing to comply with the enablement requirement.
4 Claim 6 does not specifically recite a “blood pressure signal component”;
however, claim 8, which depends from claim 6, recites “wherein the signal
of interest is a blood pressure signal component.” Appeal Br. 22–23 (Claims
App.). Hence, a blood pressure signal component is encompassed by the
parent’s (claim 6) recitation to “a signal component of interest.”
5 Appellant’s Specification distinguishes between a (genus)
electrophysiological (EP) signal and a (species) electrocardiogram (ECG)
signal stating that an EP signal can include a “respiration signal, noise, ECG
signal, etc.” Spec. ¶ 22 (emphasis added).
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pressure] appear to be different types of signals (e.g. electrical vs.
mechanical signals).” Final Act. 2 (emphasis added); see also Ans. 10, 11.
Further, according to the Examiner:
[W]hile the prior art does describe several examples of acquiring
blood pressure from an ECG and PPG sensor using a pulse transit
time, and from a PCG and ECG signal . . ., the prior art does not
appear to describe methods of determining a blood pressure from
an electrophysiological signal solely by filtering the signal. The
disclosure does not provide direction on how to acquire a blood
pressure waveform other than the idea that other waveforms can
be filtered out, and that the blood pressure waveform can be
reconstructed.
Final Act. 2–3 (emphasis added). See also Ans. 13.
Appellant points out that “independent claims 1 and 6 recite filtering
signal components specifically from an electrocardiogram signal, not an
electrophysiological signal.” Reply Br. 4. On this point, the Examiner
acknowledges that “[t]he [S]pecification provides an example in which an
ECG signal may be used to acquire a blood pressure signal, but does not
limit the signal to an ECG signal.” Ans. 12–13 (emphasis added). We note,
however, that the claims are limited to a received ECG signal which includes
a blood pressure signal component. Thus, this statement by the Examiner
regarding the Specification’s example would seem to buttress Appellant’s
position that Appellant’s Specification is at least enabling of the recited
claims.
Additionally, as regarding “how to acquire a blood pressure
waveform,” the claims on appeal recite the steps of undertaking a first
filtering operation via a “signature cycle matching pursuit method;” a second
filtering operation “by performing sub-bandwidth filtering;” and
reconstructing the desired blood pressure signal “by performing [an] inverse
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fast Fourier transform” operation. Thus, certain methodologies are recited
and as such, Appellant states that “no experimentation is required to make
and use the invention of claims 1 and 6.” Appeal Br. 10.
There is merit to Appellant’s contentions. First, the Examiner’s
premise is based upon the filtering of an “electrophysiological signal,” but
claims 1 and 6 instead recite an “electrocardiogram signal” as noted above.
The Examiner’s rejection is additionally premised on the filtering of what
appears to be a generic electrocardiogram signal that may or may not contain
a blood pressure signal component. See Final Act. 2–4; see also Ans. 13
(“the [S]pecification describes a method and system for extracting a blood
pressure signal from a generic electrophysiological signal”). However, as
indicated above, both claims 1 and 6 recite that the received and to-be-
filtered ECG signal includes a blood pressure signal component, which is to
be extracted. Appellant’s Specification also includes flowcharts and graphs,
which depict how such extraction is to occur. See also Reply Br. 4.
Paragraph 24 of Appellant’s Specification (and those that follow) begins a
more detailed description of these figures and the filtering operation recited.
Paragraph 25 of Appellant’s Specification states, “[t]he combination patient
signal may be acquired via, for example, a single surface ECG lead.” The
Examiner does not explain how these figures and associated text fail to
enable the limitations of claims 1 and 6, but instead, as indicated above, the
Examiner relies on faulty premises to reject these claims.
The Examiner additionally applies the various Wands factors to assist
in the analysis. See Final Act. 3–4; Ans. 9. For example, the Examiner
states, “[i]t is not predictable to acquire a blood pressure waveform after
filtering components from an electrophysiological signal such as an ECG
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signal.” Final Act. 3; see also Ans. 11. However, since the claims recite
that the received ECG signal already contains a blood pressure signal
component, the Examiner does not explain why it is not predictable to
acquire a blood pressure waveform by filtering the received ECG signal.6
The Examiner also acknowledges that “the [S]pecification provides a
method of reconstructing a blood pressure waveform after filtering several
components from the ECG (see pages 19–21).” Final Act. 3. The Examiner
further states, “the [S]pecification merely provides an example of filtering a
signal containing various components, and does not provide specificity
about what the signal being filtered is.” Final Act. 4. We disagree because
claims 1 and 6 are clear that it is an ECG signal that is being filtered, and
that it is the included blood pressure component that is being filtered out.
Accordingly, we conclude that the Specification provides an enabling
disclosure with respect to the claimed subject matter. For these reasons, the
Examiner’s rejection of claims 1–8 and 11–19, for failing to comply with the
enablement requirement, is not sustained.
THE REJECTION OF CLAIMS 1–8 and 11–19
UNDER 35 U.S.C. § 101
Background
An invention is patent eligible if it claims a “new and useful process,
machine, manufacture, or composition of matter.” 35 U.S.C. § 101.
However, the Supreme Court has long interpreted 35 U.S.C. § 101 to include
implicit exceptions: “[l]aws of nature, natural phenomena, and abstract

6 This is especially the case when the Examiner acknowledges that a blood
pressure signal is a “distinct” signal. Ans. 11; see also Final Act. 2 (a
“different type[]”).
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ideas” are not patentable. See, e.g., Alice Corp. v. CLS Bank Int’l, 573 U.S.
208, 216 (2014).
In determining whether a claim falls within an excluded category, we
are guided by the Supreme Court’s two-step framework, described in Mayo
Collaborative Servs. v. Prometheus Labs., Inc., 566 U.S. 66, 75–77 (2012)
and in Alice. See Alice, 573 U.S. at 217–18. In accordance with that
framework, we first determine what concept the claim is “directed to.” See
Alice, 573 U.S. at 219 (“On their face, the claims before us are drawn to the
concept of intermediated settlement, i.e., the use of a third party to mitigate
settlement risk.”); see also Bilski v. Kappos, 561 U.S. 593, 611 (2010)
(“Claims 1 and 4 in petitioners’ application explain the basic concept of
hedging, or protecting against risk.”).
Concepts determined to be abstract ideas, and thus patent ineligible,
include certain methods of organizing human activity, such as fundamental
economic practices (Alice, 573 U.S. at 219–20; Bilski, 561 U.S. at 611);
mathematical formulas (Parker v. Flook, 437 U.S. 584, 594–95 (1978)); and
mental processes (Gottschalk v. Benson, 409 U.S. 63, 69 (1972)). Concepts
determined to be patent eligible include physical and chemical processes,
such as “molding rubber products” (Diamond v. Diehr, 450 U.S. 175, 192
(1981)); “tanning, dyeing, making waterproof cloth, vulcanizing India
rubber, smelting ores” (id. at 184 n.7 (quoting Corning v. Burden, 56 U.S.
252, 267–68 (1853))); and manufacturing flour (Benson, 409 U.S. at 69
(citing Cochrane v. Deener, 94 U.S. 780, 785 (1876)).
If the claim is “directed to” an abstract idea, we turn to the second
step of the Alice and Mayo framework, where “we must examine the
elements of the claim to determine whether it contains an ‘inventive
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concept’ sufficient to ‘transform’ the claimed abstract idea into a patent-
eligible application.” Alice, 573 U.S. at 221. “A claim that recites an
abstract idea must include ‘additional features’ to ensure ‘that the [claim] is
more than a drafting effort designed to monopolize the [abstract idea].’”7 Id.
(quoting Mayo, 566 U.S. at 77).
Analysis
As stated above, claims 1–8 and 11–19 are rejected under 35 U.S.C.
§ 101 because they either recite “organiz[ing] information through
mathematical correlations and/or are representative of mathematical
relationships or formulas” (Final Act. 5) or because they recite steps that
“could be practically performed in the mind” (Ans. 14). We proceed as

7 The USPTO has published revised guidance on the application of § 101.
See USPTO’s January 7, 2019, Memorandum, 2019 Revised Patent Subject
Matter Eligibility Guidance, 84 Fed. Reg. 50 (Jan. 7, 2019), and
supplemented at 84 Fed. Reg. 55942 (Oct. 18, 2019) (“Office Guidance”).
Regarding this Office Guidance, our reviewing court stated, “the Office
Guidance is not, itself, the law of patent eligibility, does not carry the force
of law, and is not binding in our patent eligibility analysis.” In re Rudy, 956
F.3d 1379, 1383 (Fed. Cir. 2020). “To the extent the Office Guidance
contradicts or does not fully accord with our caselaw, it is our caselaw, and
the Supreme Court precedent it is based upon, that must control.” Rudy, 956
F.3d at 1383 (referencing Cleveland Clinic Found. v. True Health
Diagnostics LLC, 760 F. App’x. 1013, 1021 (Fed. Cir. 2019) (holding
claims ineligible, despite Office Guidance suggesting otherwise, where
statements and examples in the Guidance were inconsistent with Ariosa
Diagnostics, Inc. v. Sequenom, Inc., 788 F.3d 1371 (Fed. Cir. 2015)): see
also In re Zach Zunshine, No. 2020-1254, 2020 WL 3816803, at *2 (Fed.
Cir. July 8, 2020) (addressing “the Office Guidance, which we recently
reiterated does not modify or supplant controlling case law”).
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instructed by our reviewing courts:
1. Do the claims fall within a Statutory Category of § 101?
As an initial matter, we must first ascertain whether independent
claims 1 and 6 recite one of the enumerated statutory classes of subject
matter that is eligible under 35 U.S.C. § 101, namely, a process, machine,
manufacture, or composition of matter. Claim 1 recites “[a] non-transitory
computer readable medium” and claim 6 recites “[a] method.” Appeal Br.
20, 22 (Claims App.). We thus conclude that claims 1 and 6 recite an
enumerated statutory class of subject matter under 35 U.S.C. § 101. The
Examiner does not indicate otherwise. See Final Act. 5–6.
2. Are Claims 1 and 6 Directed to a Mathematical Concept or a Mental
Process?
In the Final Office Action, the Examiner determines that claims 1 and
6 recite “recite [an] abstract idea” for the reasons expressed above. Final
Act. 5; see also Ans. 14. Regarding the “mathematical concept” analysis
employed by the Examiner, the Examiner states that these claims are
abstract because the filtering technique is performed via “an inverse Fast
Fourier Transform” operation. Final Act. 5. In other words, “they merely
organize information through mathematical correlations and/or are
representative of mathematical relationships or formulas.” Final Act. 5.
Appellant contends, “[t]he claims do not recite a mathematical
relationship, formula, or calculation. While some of the claim features may
be based on mathematical concepts, the mathematical concepts are not
recited in the claims.” Appeal Br. 17. For example, “claims 1 and 6 recite
various steps for signal filtering and a signal reconstruction step that is
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merely based on or involves inverse fast Fourier transform (IFFT).” Reply
Br. 6.
Indeed, the reconstructing step recited in claims 1 and 6 states
“performing inverse fast Fourier transform (IFFT) on integrated frequency
components of the third output signal.” Appeal Br. 20, 23 (Claims App.).
However, we do not find that claims 1 and 6 are directed to a mathematical
concept by virtue of one step thereof merely reciting a particular
methodology (IFFT) by which to reconstruct a signal. The Examiner, on the
other hand, bases the “mathematical concept” rationale on this particular
recitation to an IFFT operation while also contending that the remaining
limitations “do not include additional elements that are sufficient to amount
to significantly more.” Final Act. 5.
We also disagree with the Examiner’s latter analysis (“[t]he claim(s) .
. . do not include additional elements [that] amount to significantly more”
(Final Act. 5)) as well, because claims 1 and 6 specify discrete steps by
which the desired blood pressure signal is to be obtained. For example,
claim 18 recites removing the ECG signal component from the received
signal so as to generate a first output signal by a “cycle matching pursuit
method.” Noise is then eliminated to generate a second output signal by
performing sub-bandwidth filtering of the first output signal. Afterwards,
the respiration signal component is removed from the second output signal
so as to generate a third output signal. From this third signal, a blood
pressure signal is reconstructed using an IFFT operation on this third output
signal. See also Appeal Br. 18.

8 Claim 6 includes similar language.
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Thus, in the matter before us, “[t]he asserted [] claims are analogous
to the claims at issue in Diehr and Thales9. Like the claims in Diehr, the
asserted claims ‘describe in detail a step-by-step method’ for accomplishing
a physical process” (XY, LLC v. Trans Ova Genetics, LC, 2020 WL
4378028, *5 (Fed. Cir. 2020)), and thus integrate the recited mathematical
concept into a practical application.
In view of the above, we are not in agreement with the Examiner’s
analysis that the remaining limitations (i.e., all but the IFFT operation) “do
not include additional elements that are sufficient to amount to significantly
more.” Final Act. 5. Consequently, we disagree with the Examiner’s
analysis that claims 1 and 6 recite “organiz[ing] information through
mathematical correlations and/or are representative of mathematical
relationships or formulas” and as such are directed to an abstract idea of a
“mathematical concept.” Final Act. 5.
Regarding the Examiner’s alternate rejection based on “mental
process,” the Examiner states that “the steps of eliminating noise from the
first output signal, and removing the respiration signal component could be
practically performed in the mind, as ‘sub-bandwidth filtering’ could be
defined as simple thresholding through observationally evaluating sections
of data.” Ans. 14; emphasis added. The Examiner reasons that “if a claim
limitation, under its broadest reasonable interpretation, covers performance
of the limitation in the mind but for the recitation of generic computer
components, then it is recognized as an abstract idea because it recites a
mental process.” Ans. 14.

9 Thales Visionix Inc. v. United States, 850 F.3d 1343 (Fed Cir. 2017).
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Appellant references the “October 2019 Update at pages 7-8” as
clarifying “that a claim with limitations that cannot practically be performed
in the human mind does not recite a mental process.” Reply Br. 5.
Appellant contends that, “[f]or example, claim 1 requires a several-step
manipulation of signals that cannot be practically applied in the human
mind.” Reply Br. 6. In short, Appellant contends that the claimed steps
cannot be “practically performed in the human mind, at least because they
require a processor to manipulate the signal and reconstruct the blood
pressure signal.” Reply Br. 6–7.
There is merit to Appellant’s contentions. This is, in part, because the
Examiner appears to recognize that the recited steps cannot necessarily be
performed in the human mind when stating that they can “practically” be
performed in the human mind. In other words, the Examiner is speculating
that the above filtering steps “could be practically performed in the mind.”
Ans. 14. The Examiner provides no support for the concept that a human
mind can practically perform (a) a “cycle matching pursuit method” to
generate a first output signal; (b) a “sub-bandwidth filtering” of the first
output signal to generate a second output signal; (c) removal of the
respiration signal component from the second output signal to generate a
third output signal; and, (d) inverse fast Fourier transformation on the third
output signal to reconstruct the desired blood pressure signal. See also
Reply Br. 8.
It is also not self-evident that such steps “could be practically
performed in the mind” as stated. Ans. 14. We thus fail to see how the
recited steps, including the different signals that are generated, eliminated,
and reconstructed, can be said by the Examiner to be “an abstract idea
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because it recites a mental process.” Ans. 14. As noted above, “the asserted
claims ‘describe in detail a step-by-step method.’” XY, 2020 WL at *5. As
such, we also do not agree with the Examiner that claims 1 and 6 are
directed to a mental process.
For these reasons, we conclude that claims 1 and 6 are not directed to
an abstract idea, and are, instead, directed to patent-eligible subject matter.
Accordingly, the rejection of claims 1–8 and 11–19 under 35 U.S.C. § 101
as being directed to patent-ineligible subject matter is not sustained.
DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C. § Reference(s)/Basis  Affirmed Reversed
1–8, 11–
19
112(a) Enablement 1–8, 11–19
1–8, 11–
19
101 Eligibility 1–8, 11–19
Overall
Outcome
1–8, 11–19

REVERSED