DIGNITY HEALTH

Patent Trials and Appeals Board

Mar 1, 2021

2020003932 (P.T.A.B. Mar. 1, 2021)

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.
15/031,141 04/21/2016 Stephen L. Macknik 128464.00183 2670
26710 7590 03/01/2021
QUARLES & BRADY LLP
ATTN: IP DOCKET
411 E. WISCONSIN AVENUE
SUITE 2350
MILWAUKEE, WI 53202-4428
EXAMINER
PERREIRA, MELISSA JEAN
ART UNIT PAPER NUMBER
1618
NOTIFICATION DATE DELIVERY MODE
03/01/2021 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):
pat-dept@quarles.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte STEPHEN L. MACKNIK,
SUSANA MARTINEZ-CONDE, and HECTOR RIEIRO
____________

Appeal 2020-003932
Application 15/031,141
Technology Center 1600
____________

Before DONALD E. ADAMS, ERIC B. GRIMES, and
JAMIE T. WISZ, Administrative Patent Judges.

WISZ, Administrative Patent Judge.

DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134(a), Appellant1 seeks review of claims 1,
4–10, 13–16, and 21–24. We have jurisdiction under 35 U.S.C. § 6(b).
For the reasons set forth below, 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 Dignity
Health. Appeal Br. 2.
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CLAIMED SUBJECT MATTER
The Specification describes the recognition that “pericyte information,
generated in vivo, may be used in identifying and/or treating a subject
condition, such as a neural degeneration condition elicited by epilepsy, as
well as other conditions.” Spec. ¶ 7. Pericytes are described as
“perivascular cells that wrap around endothelial cells of capillaries and
venules throughout the body, and are responsible for multiple physiological
functions.” Id. at ¶ 26. The Specification further describes methods and kits
for producing pericyte information “using intravenous administration of an
effective amount of a solution including fluorescent markers that can
selectively label pericytes.” Id. at ¶ 8.
Claims 1, 10, and 21, reproduced below, are the independent claims:
1. A method for identifying a subject condition, the method
comprising:
administering intravenously to a subject an effective amount of
an injectable solution comprising fluorescent conjugated
Dextran markers, having a molecular weight in a range
between 3 kiloDaltons and 70 kiloDaltons, to selectively
label pericytes throughout the subject’s body;
acquiring, using an imaging system, fluorescence signals
originating from labeled pericytes to produce pericyte
information associated with tissues of the subject’s body;
and
generating a report identifying a subject condition using the
pericyte information.

10. A method for treating a subject condition, the method
comprising:
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administering intravenously to a subject an effective amount of
an injectable solution comprising fluorescent conjugated
Dextran markers, having a molecular weight in a range
between 3 kiloDaltons and 70 kiloDaltons, to selectively
label pericytes throughout the subject’s body;
acquiring, using an imaging system, fluorescence signals
originating from labeled pericytes to produce pericyte
information associated with tissues of the subject’s body;
identifying a subject condition using the pericyte information;
and
adapting a treatment using the identified subject condition.

21. A method for staining pericytes in a subject, the method
comprising steps of:
providing an effective amount of an injectable solution
comprising fluorescently conjugated dextran, the
fluorescently conjugated dextran having a molecular weight
in a range between 3 kiloDaltons and 70 kiloDaltons and
being capable of selectively labeling pericytes throughout
the subject; and
administering intravenously to the subject the effective amount
of the injectable solution such that the fluorescently
conjugated dextran selectively binds to pericytes in the
subject.
Appeal Br. 26–28 (Claims Appendix).
REJECTIONS
The Examiner rejected claims 1, 4–10, 13–16, and 21–24 under 35
U.S.C. § 101 as being directed to patent-ineligible subject matter.
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The Examiner rejected claims 1, 5 and 7 under 35 U.S.C. § 103(a) as
obvious over Hirase.2
The Examiner rejected claims 1, 4–10, 13–16, and 21–23 under 35
U.S.C. § 103(a) as obvious over Choi3 in view of Guerin,4 Caruso,5 and
Hirase and further in view of Richardson,6 Bell,7 and Comeau.8
ISSUES AND ANALYSIS
Rejection of claims 1, 4–10, 13–16, and 21–24 under 35 U.S.C. § 101 as
being directed to patent-ineligible subject matter.
The Examiner finds that claims 1, 4–10, 13–16, and 21–24 are
directed to a judicial exception without significantly more. Final Act. 3.
Specifically, the Examiner finds that the “claimed invention is directed to
the administration of a fluorescent marker to a subject to image pericytes

2 Hirase et al., Two-Photon Imaging of Brain Pericytes In Vivo Using
Dextran-Conjugated Dyes, GLIA, 46, 95–100 (2004) (“Hirase”).
3 Choi et al., WO 2012/099448 A2, published July 26, 2012 (“Choi”).
4 Guerin et al., The Dynamics of Blood-Brain Barrier Breakdown in an
Experimental Model of Glial Cell Degeneration, Neuroscience, Vol. 103,
No. 4, 873–883 (2001) (“Guerin”).
5 Caruso, et al. Ultrastructural Descriptions of Pericyte/Endothelium Peg-
socket Interdigitations in the Microvasculature of Human Gastric
Carcinomas, Anticancer Research 29:449–454 (2009) (“Caruso”).
6 Richardson et al., US 2006/0188492 A1, published Aug. 24, 2006
(“Richardson”).
7 Bell et al., Pericytes Control Key Neurovascular Functions and Neuronal
Phenotype in the Adult Brain and during Brain Aging, Neuron 68, 409–427
(2010) (“Bell”).
8 Comeau et al., US 2006/0039910 A1, published Feb. 23, 2006
(“Comeau”).
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which is detecting a natural phenomenon wherein pericytes are located
throughout the body.” Id. The Examiner further finds that “[t]he
administration of fluorescent markers and detection of the fluorescent
markers throughout the body are routine and customary.” Id. In support of
this position, the Examiner cites to Hirase. The Examiner finds that Hirase
“teaches of the administration of dextran fluorescent markers (e.g. Calcium
Green I dextran) to selectively label a plurality of pericytes and the detection
of pericytes.” Id.
A. Principles of Law
1. Section 101
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 U.S. Supreme Court has long interpreted 35 U.S.C. § 101 to
include implicit exceptions: “[l]aws of nature, natural phenomena, and
abstract ideas” are not patentable. 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 Court’s two-part framework, described in Mayo and Alice.
Id. at 217–18 (citing Mayo Collaborative Servs. v. Prometheus Labs., Inc.,
566 U.S. 66, 75–77 (2012)). In accordance with that framework, we first
determine whether the claim recites a judicial exception. 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
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in petitioners’ application explain the basic concept of hedging, or protecting
against risk.”).
If the claim is “directed to” a judicial exception—a law of nature, a
natural phenomenon, or 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 concept’ sufficient to
‘transform’ the claimed abstract idea into a patent-eligible application.”
Alice, 573 U.S. at 221 (quotation marks omitted). “If a law of nature is not
patentable, then neither is a process reciting a law of nature, unless that
process has additional features that provide practical assurance that the
process is more than a drafting effort designed to monopolize the law of
nature itself.” Mayo, 566 U.S. at 77.
2. USPTO Section 101 Guidance
In January 2019, the U.S. Patent and Trademark Office (USPTO)
published revised guidance on the application of § 101. 2019 Revised Patent
Subject Matter Eligibility Guidance, 84 Fed. Reg. 50 (Jan. 7, 2019) (“2019
Revised Guidance”).9 “All USPTO personnel are, as a matter of internal
agency management, expected to follow the guidance.” Id. at 51; see also
October 2019 Update at 1.

9 The Office issued further guidance on October 17, 2019. USPTO, October
2019 Update: Subject Matter Eligibility (the “October 2019 Update”)
(available at
https://www.uspto.gov/sites/default/files/documents/peg_oct_2019_update.p
df).
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Under the 2019 Revised Guidance and the October 2019 Update, we
first look to whether the claim recites:
(1) any judicial exceptions, including certain groupings of
abstract ideas (i.e., mathematical concepts, certain methods
of organizing human activity such as a fundamental
economic practice, or mental processes) (“Step 2A, Prong
One”); and
(2) additional elements that integrate the judicial exception into
a practical application (see MPEP § 2106.05(a)–(c), (e)–(h)
(9th ed. Rev. 08.2017, Jan. 2018)) (“Step 2A, Prong
Two”).10
2019 Revised Guidance, 84 Fed. Reg. at 52-55.
Only if a claim (1) recites a judicial exception and (2) does not
integrate that exception into a practical application, do we then look, under
Step 2B, to whether the claim:
(3) adds a specific limitation beyond the judicial exception that
is not “well-understood, routine, conventional” in the field
(see MPEP § 2106.05(d)); or
(4) simply appends well-understood, routine, conventional
activities previously known to the industry, specified at a
high level of generality, to the judicial exception (“Step
2B”).
2019 Revised Guidance, 84 Fed. Reg. at 52–56.

10 This evaluation is performed by (a) identifying whether there are any
additional elements recited in the claim beyond the judicial exception, and
(b) evaluating those additional elements individually and in combination to
determine whether the claim as a whole integrates the exception into a
practical application. See 2019 Revised Guidance — Section III(A)(2), 84
Fed. Reg. 54–55.
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B. Revised Guidance Step 2A, Prong 1
Following the Revised Guidance, we first consider whether the claims
recite a judicial exception. Claims 1 and 10 both recite the steps of
“acquiring . . . fluorescence signals originating from labeled pericytes to
produce pericyte information associated with tissues of the subject’s body”
and “identifying a subject condition using the pericyte information.”
The Revised Guidance identifies “a law of nature, or a natural
phenomenon” as being among the judicial exceptions to patentability. 84
Fed. Reg. at 54.
Here, we agree with the Examiner that the correlation between
pericyte information and certain conditions is a natural phenomenon. The
Specification discloses that pericyte information may be used in identifying
a condition such as a neural degeneration condition elicited by epilepsy.
Spec. ¶ 7. According to the Specification, “such pericyte information can
include information related to pericyte functionality, morphology, location,
size, number, separation, spatial distribution, and so on.” Id. at ¶ 35.
In Mayo, the Court held that “Prometheus’ patents set forth laws of
nature—namely, relationships between concentrations of certain metabolites
in the blood and the likelihood that a dosage of a thiopurine drug will prove
ineffective or cause harm.” 566 U.S. at 77. Similarly here, Appellant’s
claims set forth laws of nature—namely, relationships between the pericyte
information (e.g., location, size, number, spatial distribution), and certain
conditions. Therefore, claims 1 and 10 recite a judicial exception to
patentability.
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With regard to claim 21, however, we find that it does not recite a
judicial exception. Claim 21 recites a method for staining pericytes by
administering intravenously an effective amount of an injectable solution
comprising fluorescently conjugated dextran that selectively binds to
pericytes in the subject. These steps do not recite or describe any recognized
exception. See Mayo Collaborative Svcs. v. Prometheus Labs., 566 U.S. 66,
78 (2012) (recited steps of administering a drug to a patient and determining
the resultant level of 6-thioguanine in the patient “are not themselves natural
laws”); see also USPTO May 2016 Subject Matter Eligibility Examples11
(finding claim 1 of Example 29, reciting a method of detecting JUL-1 in a
patient, to be patent eligible).
C. Revised Guidance Step 2A, Prong 2
Even though claims 1 and 10 recite a natural phenomenon, they would
still be patent-eligible if “the claim as a whole integrates the recited judicial
exception into a practical application of the exception.” 2019 Revised
Guidance, 84 Fed. Reg. at 54. “A claim that integrates a recited judicial
exception into a practical application will apply, rely on, or use the judicial
exception in a manner that imposes a meaningful limit on the judicial
exception, such that the claim is more than a drafting effort designed to
monopolize the judicial exception.” Id.

11 Available at
https://www.uspto.gov/sites/default/files/documents/101_examples_1to36.p
df.
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The analysis of determining whether the claim integrates the judicial
exception into a practical application includes “[i]dentifying whether there
are any additional elements recited in the claim beyond the judicial
exception(s)” and “evaluating those additional elements individually and in
combination to determine whether they integrate the exception into a
practical application.” Id. at 54–55.
Appellant asserts that “the examiner fails to perform step 2A, prong 2
of the test upon asserting that the claims were directed toward a judicial
exception” by “fail[ing] to analyze whether the claim is integrated into a
practical application.” Appeal Br. 5.
We agree with Appellant. Claims 1 and 10 both recite the additional
step of “administering intravenously to a subject an effective amount of an
injectable solution comprising fluorescent conjugated Dextran markers . . .
to selectively label pericytes throughout the subject’s body.” The Examiner
did not conduct an analysis as to whether the additional elements in this step
(or other additional elements recited in the claims), individually or in
combination, integrate the exception into a practical application. Instead, the
Examiner discusses “routine, and conventional activities” which are the
relevant considerations for Step 2B, rather than Step 2A, Prong 2. See Ans.
12. Therefore, we find that the Examiner did not sufficiently establish that
claims 1 and 10 do not have additional elements that integrate the exception
into a practical application.
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D. Revised Guidance Step 2B
Furthermore, even if the Examiner had properly conducted such an
analysis under Step 2A, Prong 2, these claims would still be eligible under
Step 2B because the Examiner failed to show that the step of administering
intravenously an effective amount of an injectable solution comprising
fluorescent conjugated Dextran markers to selectively label pericytes
throughout a subject’s body was routine or conventional.
The Revised Guidance directs us to consider whether claim 1 includes
“additional elements . . . [that] provide[] ‘significantly more’ than the recited
judicial exception.” 84 Fed. Reg. at 56. The Revised Guidance states that
an additional element that “simply appends well-understood, routine,
conventional activities previously known to the industry, specified at a high
level of generality, to the judicial exception, . . . is indicative that an
inventive concept may not be present.” Id. However, an additional element
that “[a]dds a specific limitation or combination of limitations that are not
well-understood, routine, conventional activity in the field, . . . is indicative
that an inventive concept may be present.” Id.
“The question of whether a claim element or combination of elements
is well-understood, routine and conventional to a skilled artisan in the
relevant field is a question of fact.” Berkheimer v. HP Inc., 881 F.3d 1360,
1368 (Fed. Cir. 2018). “Whether a particular technology is well-understood,
routine, and conventional goes beyond what was simply known in the prior
art. The mere fact that something is disclosed in a piece of prior art, for
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example, does not mean it was well-understood, routine, and conventional.”
Id. at 1369.
“In rejecting an application, factual determinations by the PTO must
be based on a preponderance of the evidence.” In re Oetiker, 977 F.2d 1443,
1449 (Fed. Cir. 1992) (J. Plager, concurring). In this case, the Examiner
cites to Hirase as evidence that “the administration of a fluorescent marker
to a subject and detection of the fluorescent marker is routine and customary
in the prior art.” Final Act. 3. We first note that the Examiner describes the
routine nature of the generic concept of the administration and detection of
fluorescent markers but fails to provide evidence that the intravenous
administration of Dextran markers to selectively label pericytes throughout a
subject’s body was well-understood, routine, or conventional. Second, for
the reasons discussed below with respect to the rejections under 35 U.S.C.
§ 103, we find that Hirase does not disclose such intravenous administration.
We recognize that novelty and non-obviousness are not the test of eligibility
under Section 101. See Data Engine Techs. LLC v. Google LLC, 906 F.3d
999, 1011 (Fed. Cir. 2018). However, the Examiner has not put forward any
additional evidence to establish that such intravenous administration was
“routine and customary.”
Therefore, for the reasons discussed above, we reverse the Examiner’s
rejections of claims 1, 4–10, 13–16, and 21–24 under 35 U.S.C. § 101 as
being directed to patent-ineligible subject matter.

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Rejection of claims 1, 5 and 7 under 35 U.S.C. § 103(a) as obvious over
Hirase.
The Examiner finds that Hirase “discloses a method for identifying a
subject condition comprising administering to a subject an effective amount
of an injectable solution comprising fluorescent markers (e.g. Calcium
Green I dextran) to selectively label a plurality of pericytes in the subject’s
body.” Non-Final Act.12 3 (citing Hirase Abstract, 98). The Examiner
further finds that “[t]he selective in vivo labeling of pericytes with functional
markers may help reveal their physiological function in neuronal activity-
associated regulation of local cerebral blood flow” and that Calcium Green I
dextran has a molecular weight of 10kD. Id. at 3–4 (citing Hirase 96).
Appellant contends that Hirase does not teach intravenous
administration of dyes for labeling of pericytes but, rather, teaches an
invasive approach for locally labeling pericytes that requires direct focal
injection of dyes. Appeal Br. 13. Specifically, Appellant asserts that
“Hirase states that ‘no methods are known to label pericytes selectively’ and
provides a new process for labeling brain pericytes involving removing a
piece of bone from the skull and infusing a dextran-containing dye via a
glass pipette in the visual cortex.” Id. at 12 (citing Hirase 95, 96).
The Examiner responds that “Hirase teaches in vivo administration
but in a different manner” and that “[i]t would have been obvious to the
skilled artisan to examine intravenous administration for the clear advantage
of eliminating the need for an invasive approach.” Ans. 13. The Examiner

12 Non-Final Action mailed Sept. 17, 2018 (“Non-Final Act.”).
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further finds that “[p]ericytes are found throughout the body and therefore, it
would have been expected that pericytes, located throughout the body, can
be labeled with dextran dyes without the need for administration through the
skull.” Id.
We agree with Appellant that Hirase does not render obvious the
intravenous administration of Dextran markers to selectively label pericytes
throughout a subject’s body. As discussed by Appellant, Hirase discloses a
method for labeling pericytes by removing a piece of the skull and inserting
the dextran-containing dye via a pipette into the visual cortex. Hirase 96.
After such dye administration, it was found that “pericytes are labeled on a
small subset of vessels” and that “[i]n addition to pericytes, astrocytes and
capillary endothelial cells were also labeled in the vicinity (~300 µm) of the
injection site.” Id. at 96, 98.
We do not find that, based on this teaching, it would have been
obvious to one of ordinary skill in the art to administer Dextran dyes
intravenously to achieve selective labeling of pericytes throughout a
subject’s body nor would the artisan have a reasonable expectation of
success that such administration would be able to selectively label such
pericytes based on the teachings of Hirase. Rather than disclosing an
intravenous administration of dye, Hirase discloses an invasive procedure
for pericyte labeling, which does not even appear to be entirely selective
(i.e., astrocytes and capillary endothelial cells were also labeled near the
injection site). Id. When Hirase does disclose intravenous administration of
a dye, it is to visualize the cerebral vasculature to distinguish from the
labeled pericytes. Id. at 98. Furthermore, Hirase does not disclose or
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suggest selectively labeling pericytes throughout the entire body. In fact,
Hirase discloses that “labeling at distant sites was sparse.” Id.
Thus, we find that Hirase does not render the claims obvious and the
Examiner’s reasoning that a skilled artisan would have expected to be able
to selectively label pericytes throughout the body using intravenous dye
administration is based on improper hindsight. “The Patent Office has the
initial duty of supplying the factual basis for its rejection. It may not . . .
resort to speculation, unfounded assumptions or hindsight reconstruction to
supply deficiencies” in the cited references. In re Warner, 379 F.2d 1011,
1017 (CCPA 1967).
Therefore, for the reasons discussed above, we reverse the Examiner’s
rejections of claims 1, 5, and 7 as being obvious over Hirase.
Rejection of claims 1, 4–10, 13–16, and 21–23 under 35 U.S.C. § 103(a) as
obvious over Choi in view of Guerin, Caruso, and Hirase and further in
view of Richardson, Bell, and Comeau
The Examiner finds that Choi “teaches that in order to examine
pericytes surrounding the retinal vessels, immunofluorescence staining of
angiography with infusion of TMR-D (10 mg/ml) was performed to dye to
the blood vessels and pericytes with the pericyte marker αSMA.” Final Act.
7. The Examiner further finds that even though Choi does not explicitly
disclose intravenous administration, it does teach visualizing pericytes after
infusion of TMR-D. Id. The Examiner also finds that Guerin discloses
“leakage of fluorescent dextrans to demonstrate the breakdown of the blood-
brain barrier” and that “[p]ericytes of both leaky and non-leaky vessels in
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affected areas were sometimes strongly labelled with low molecular weight
dextrans.” Non-Final Act. 8–9.
The Examiner further finds that Caruso “teaches that pericytes exhibit
several types of surface contact with endothelial cells, including gap
junctions, adhesion plaques and peg-socket junctions wherein the gap
junctions provide direct connections between the cytoplasm of the two cells
and allow the passage of ionic currents and small molecules” and that Hirase
shows “pericytes at junction points of blood vessels.” Final Act. 8. The
Examiner acknowledges that Caruso does not teach intravenous
administration of solutions for labeling pericytes but concludes that, “it
would have been obvious to one of ordinary skill in the art that leakage at
the junctions of Hirase will allow for labeling of pericytes with fluorescent
conjugated dextran markers as pericytes are located at these junctions and
that pericytes may also be labeled via other types of junctions, such as that
of Caruso.” Id.; Ans. 16.
The Examiner appears to rely on Richardson, Bell, and Comeau for
the rejection of certain dependent claims.
Appellant argues, inter alia, that the cited references, alone or in
combination, do not teach or suggest “administering intravenously to a
subject an effective amount of an injectable solution comprising fluorescent
conjugated Dextran markers, having a molecular weight in a range between
3 kiloDaltons and 70 kiloDaltons, to selectively label pericytes throughout
the subject’s body.” Appeal Br. 18.
We agree with Appellant that the teachings of Choi in view of Guerin,
Caruso, and Hirase and further in view of Richardson, Bell, and Comeau do
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not render the claims obvious. As discussed above regarding the
obviousness rejection over Hirase alone, none of the references cited by the
Examiner teach the intravenous administration of Dextran markers to
selectively label pericytes throughout the subject’s body. With regard to
Choi, the Examiner acknowledges that Choi “was not used to teach []
intravenous administration,” but, rather was used to teach utilizing “the
imaging information and data provided by the administration of TMR-D
diabetic patients to view the number of pericytes and vessel leakage to
determine whether there is pericytic loss and identify retinal diseases as
pericyte loss and BRB breakdown are characteristic features in early diabetic
retinopathy.” Ans. 14–15.
The Examiner relies on Guerin to teach that “pericytes of both leaky
and non-leaky vessels in affected areas were sometimes strongly labelled
with low molecular weight dextrans.” Id. at 15. However, Guerin does not
teach selective labeling of pericytes throughout the body. As pointed out by
Appellant, the control animals of Guerin did not show any pericyte labeling.
Furthermore, although Guerin teaches that “[s]ome pericytes in affected
areas internalized [] low molecular weight dextrans,” this labeling does not
appear to have been selective because endothelial cells were also labeled
along with the pericytes. See Guerin 875, 880, Fig. 4. The Examiner has
also not established that the pericyte labeling of Guerin was throughout the
subject’s body.
In addition, the Examiner has not sufficiently established a motivation
to combine Guerin with the other cited references. The studies of Guerin
“were undertaken to investigate the dynamics of blood-brain barrier
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breakdown in an in vivo rat model of selective CNS vulnerability.” Id. at
873. The Examiner relies on Guerin for teaching that “pericytes of both
leaky and non-leaky vessels in affected areas were sometimes strongly
labelled with low molecular weight dextrans” but does not provide any
rationale as to why one of ordinary skill in the art would combine the
teachings of Choi and Guerin.
With regard to Hirase and Caruso, the Examiner finds that “it would
have been obvious to one of ordinary skill in the art that leakage at the
junctions of Hirase will allow for labeling of pericytes with fluorescent
conjugated dextran markers as pericytes are located at these junctions and
that pericytes may also be labeled via other types of junctions, such as that
of Caruso.” Id. Ans. 15, 16. However, as discussed above, Hirase does not
teach the intravenous administration of Dextran markers for selectively
labeling pericytes throughout the body. Similarly, we agree with Appellant
that “Caruso does not teach intravenous administration of solutions (but
rather works with surgically resected specimens), does not teach labeling
pericytes in any way, and does not teach using any type of fluorescent
conjugated Dextran markers.” Appeal Br. 20. The Examiner has not
sufficiently established why the combination of Guerin with Hirase or
Caruso (or the other cited references), would have rendered the claims
obvious. “We must still be careful not to allow hindsight reconstruction of
references to reach the claimed invention without any explanation as to how
or why the references would be combined to produce the claimed
invention.” Innogenetics, N.V. v. Abbott Labs., 512 F.3d 1363, 1374 n.3
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(Fed. Cir. 2008). The other references cited by the Examiner do not cure
these deficiencies.
Therefore, for the reasons discussed above, we reverse the Examiner’s
rejections of claims 1, 4–10, 13–16, and 21–23 as being obvious over Choi
in view of Guerin, Caruso, and Hirase and further in view of Richardson,
Bell, and Comeau.
DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
1, 4–10, 13–
16, 21–24
101 Eligibility 1, 4–10, 13–
16, 21–24
1, 5, 7 103(a) Hirase 1, 5, 7
1, 4–10, 13–
16, 21–23
103(a) Choi, Guerin,
Caruso, Hirase,
Richardson, Bell,
Comeau
1, 4–10, 13–
16, 21–23
Overall
Outcome
1, 4–10, 13–
16, 21–24

REVERSED