Bio-Rad Laboratories, Inc.

Patent Trials and Appeals Board

Apr 26, 2021

IPR2020-00086 (P.T.A.B. Apr. 26, 2021)

Trials@uspto.gov Paper 39
571-272-7822 Date: April 26, 2021

UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE PATENT TRIAL AND APPEAL BOARD

10X GENOMICS, INC.,
Petitioner,
v.
BIO-RAD LABORATORIES, INC.,
Patent Owner.

IPR2020-00086
Patent 9,562,837 B2

Before CHRISTOPHER M. KAISER, KIMBERLY McGRAW, and
ELIZABETH M. ROESEL, Administrative Patent Judges.
ROESEL, Administrative Patent Judge.
DECISION
Final Written Decision
Determining Some Challenged Claims Unpatentable
35 U.S.C. § 318(a)
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I. INTRODUCTION
A. Background and Summary
10X Genomics, Inc. (“Petitioner”) filed a Petition (Paper 2, “Pet.”)
seeking inter partes review of claims 1–4, 7–13, 19, and 20 (“the challenged
claims”) of U.S. Patent No. 9,562,837 B2 (“the ’837 Patent”). Bio-Rad
Laboratories, Inc. (“Patent Owner”) filed a Preliminary Response. Paper 7.
On April 27, 2020, we instituted an inter partes review. Paper 8 (“Inst.
Dec.”).
After institution, Patent Owner filed a Patent Owner Response
(Paper 26, “PO Resp.”), Petitioner filed a Reply (Paper 29, “Pet. Reply”),
and Patent Owner filed a Sur-reply (Paper 31, “PO Sur-reply”). An oral
hearing was held on January 27, 2021, and a transcript of the hearing is
included in the record. Paper 38.
We have jurisdiction under 35 U.S.C. § 6. This Final Written
Decision is issued pursuant to 35 U.S.C. § 318(a). For the reasons that
follow, we determine that Petitioner has shown by a preponderance of the
evidence that some, but not all, of the challenged claims of the ’837 Patent
are unpatentable.
The Petition presents two theories of obviousness, one based on the
disclosure of wells and another based on the disclosure of density sorters.
Pet. 23–24, 31, 56. The parties’ dispute concerning Petitioner’s first theory
centers on whether the asserted references teach or suggest a “separation
chamber” and “droplet receiving outlet” as recited in the challenged claims.
For the reasons that follow, we determine that Ismagilov 091, alone or in
combination with Quake, discloses an open-topped outlet well or reservoir
that satisfies Patent Owner’s claim constructions for “separation chamber”
and “droplet receiving outlet.” The parties’ dispute concerning Petitioner’s
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second theory centers on whether Ismagilov 119’s disclosure of sorting
droplets based on density would have suggested a “separation chamber” as
recited in the challenged claims or would have been combined with
Pamula’s disclosure of separating one phase from another phase based on a
difference in density. For the reasons that follow, we determine that
Petitioner has not proven its case based on this second theory.
B. Real Parties in Interest
Pursuant to 37 C.F.R. § 42.8(b)(1), Petitioner identifies
10X Genomics, Inc. as the real party in interest. Pet. 71. Patent Owner
identifies Bio-Rad Laboratories, Inc. as the real party in interest. Paper 24
(Updated Mandatory Notice).
C. Related Matters
Pursuant to 37 C.F.R. § 42.8(b)(2), the parties identify the following
district court action: Bio-Rad Laboratories, Inc. v. 10X Genomics, Inc.,
No. 1:18-cv-01679-RGA (D. Del.). Pet. 71; Paper 24.
There are three related cases before the Board involving the same
parties and the same patent or a related patent. IPR2020-00087 involves the
’837 Patent, and IPR2020-00088 and IPR2020-00089 involve U.S. Patent
No. 9,896,722 B2, which is a continuation-in-part of the ’837 Patent. The
January 27, 2021, oral hearing transcript (Paper 38) pertains to all four cases.
D. The ’837 Patent
The ’837 Patent was issued on an application filed April 2, 2013, and
lists a number of provisional and non-provisional priority applications, the
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earliest of which were filed May 11, 2006. Pet. 3; Ex. 1001, codes (22),
(60), (63).1
The ’837 Patent is titled “Systems for Handling Microfludic [sic]
Droplets.” Ex. 1001, code (54). The ’837 Patent discloses an assembly that
includes a droplet formation module and a chamber. Id. at code (57);
3:11–12, 3:36–37, 52:38–39, 53:21–22. The droplet formation module is
configured to form droplets surrounded by an immiscible fluid. Id. at
code (57); 3:12–20, 52:38–48. The chamber is configured to receive
droplets and immiscible fluid and has an outlet configured to receive
substantially only droplets. Id. at code (57), 3:37–48, 53:22–25. According
to the ’837 Patent, the assembly is “particularly useful for reducing potential
contamination associated with sample handing.” Id. at 52:27–29.

1 Petitioner argues that the America Invents Act (“AIA”) applies to the ’837
Patent because the application that led to the ’837 Patent contained new
matter and claims to that new matter with an effective filing date of April 2,
2013. Pet. 5. We do not need to determine whether or not the AIA applies
because on this record, as discussed below, Petitioner’s asserted references
are prior art to the ’837 Patent under either the AIA or pre-AIA version of
35 U.S.C § 102.
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Figure 38 of the ’837 Patent is reproduced below:

Figure 38 shows a microfluidic assembly that includes a droplet formation
module and a chamber. Ex. 1001, 8:22–23, 53:47–48, 53:62–65, 54:34–41.
The droplet formation module includes sample input 801, channel 802, and
oil input 803. Id. at 53:62–65. The assembly includes chamber 804
equipped with outlet 805, which is connected to slide 806, which is in turn
connected to output nozzle or exit port 807. Id. at 54:34–41, 54:47–57,
54:61–63. The assembly also includes reagent input 808 and coalescence
module 809. Id. at 54:4–6, 54:19–22.
An aqueous sample solution is introduced through sample input 801,
and oil is introduced through oil input 803. Ex. 1001, 53:48–50, 53:59–60.
The oil and aqueous solution meet at a junction in channel 802 such that the
aqueous solution is segmented by the oil, thereby forming droplets. Id.
at 53:60–62. “As the oil containing the droplets moves along the assembly
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through the channel 802, the oil and droplets begin to enter the
chamber 804.” Id. at 54:37–39. “Due to the difference in their respective
densities, the oil and droplets separate from each other in the chamber 804.”
Id. at 54:39–41. Droplets exit chamber 804 into outlet 805 “leaving a large
part of the oil behind.” Id. at 54:41–44. Droplets exiting chamber 804
through outlet 805 enter slide 806 and travel though the slide and nozzle
807, which leads to a vessel or container for collecting the droplets. Id.
at 54:51–59.
E. Illustrative Claim
The ’837 Patent includes 20 claims. Claim 1 is the sole independent
claim and is reproduced below, with paragraph breaks adjusted and
bracketed numbers added to correspond with Petitioner’s identification of
claim elements:
1. [1.0] An assembly, the assembly comprising:
[1.1] a microchannel in a horizontal plane;
[1.2] at least one droplet formation module comprising a
sample inlet, an immiscible fluid inlet, and a junction, wherein
the junction is located between the sample inlet and the
microchannel and the droplet formation module is configured to
produce droplets comprising the sample surrounded by the
immiscible fluid; and
[1.3] at least one downstream separation chamber
comprising a droplet receiving chamber inlet and at least one
droplet receiving outlet,
[1.4] wherein the separation chamber is upright to the
microchannel and out of the horizontal plane;
[1.5] wherein the droplet formation module and the
separation chamber are in fluid communication with each other
via the microchannel;
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[1.6] and wherein the separation chamber has a wider
cross-section than the microchannel cross-section to accumulate
a plurality of droplets comprising the sample and
[1.7] is of a volume sufficient to separate the plurality of
droplets comprising the sample from the immiscible fluid within
the separation chamber.
Ex. 1001, 88:2–23; see also Pet. 31–45 (identifying claim elements).
F. Asserted Grounds and References
Petitioner asserts the following grounds of unpatentability:
Claims Challenged 35 U.S.C. § Reference(s)
1 1, 2, 4, 10–13, 19, 20 102 Ismagilov 0912
2 1, 2, 4, 7, 9–13, 19, 20 103 Ismagilov 091, Quake3
3 1–4, 7–13, 19, 20 103 Ismagilov 1194
4 1–4, 7–13, 19, 20 103 Ismagilov 119, Pamula 6345
5 1–4, 7–13, 19, 20 103 Ismagilov 119, Pamula 2386
G. Testimonial Evidence
In addition to the prior art cited above, Petitioner relies on a
Declaration of Richard B. Fair, Ph.D. (Ex. 1008) and a second declaration of
Dr. Fair (Ex. 1071) filed with the Reply. Patent Owner cross-examined

2Ex. 1004, Ismagilov et al., US 7,129,091 B2, issued Oct. 31, 2006
(“Ismagilov 091”).
3Ex. 1006, Quake et al., US 2002/0058332 A1, published May 16, 2002
(“Quake”).
4Ex. 1005, Ismagilov et al., US 2006/0094119 A1, published May 4, 2006
(“Ismagilov 119”).
5Ex. 1007, Pamula et al., US 2007/0243634 A1, published Oct. 18, 2007
(“Pamula 634”).
6Ex. 1018, Pamula et al., US 2015/0148238 A1, published May 28, 2015
(“Pamula 238”).
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Dr. Fair twice and filed a transcript of the first deposition as Exhibit 2017
and the second deposition as Ex. 2041.
Patent Owner relies on a Declaration of Shelley Anna, Ph.D.
Ex. 2016. Petitioner cross-examined Dr. Anna and filed a transcript of the
deposition as Exhibit 1075.
II. DISCUSSION
A. Legal Standards
“In an [inter partes review], the petitioner has the burden from the
onset to show with particularity why the patent it challenges is
unpatentable.” Harmonic Inc. v. Avid Tech., Inc., 815 F.3d 1356, 1363 (Fed.
Cir. 2016) (citing 35 U.S.C. § 312(a)(3) (requiring inter partes review
petitions to identify “with particularity . . . the evidence that supports the
grounds for the challenge to each claim”)); see also 37 C.F.R. § 42.104(b)
(2019) (requiring a petition for inter partes review to identify how the
challenged claim is to be construed and where each element of the claim is
found in the prior art patents or printed publications relied upon).
A claim is anticipated under 35 U.S.C. § 102 only if “each and every
element as set forth in the claim is found, either expressly or inherently
described, in a single prior art reference.” Verdegaal Bros. v. Union Oil Co.,
814 F.2d 628, 631 (Fed. Cir. 1987). “In the context of anticipation, the
question is not whether a prior art reference ‘suggests’ the claimed subject
matter.” AstraZeneca LP v. Apotex, Inc., 633 F.3d 1042, 1055 (Fed. Cir.
2010) (quoting party’s argument). “Rather, the dispositive question
regarding anticipation is whether one skilled in the art would reasonably
understand or infer from a prior art reference that every claim element is
disclosed in that reference.” Id. (brackets and internal quotes omitted).
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“[A]nticipation by inherent disclosure is appropriate only when the reference
discloses prior art that must necessarily include the unstated limitation.”
Rexnord Indus., LLC v. Kappos, 705 F.3d 1347, 1355 (Fed. Cir. 2013).
A claim is unpatentable under 35 U.S.C. § 103 if “the differences
between the subject matter sought to be patented and the prior art are such
that the subject matter as a whole would have been obvious at the time the
invention was made to a person having ordinary skill in the art to which said
subject matter pertains.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 406
(2007). The question of obviousness is resolved based on underlying factual
determinations including: (1) the scope and content of the prior art; (2) any
differences between the claimed subject matter and the prior art; (3) the level
of skill in the art; and (4) when in evidence, objective evidence of
nonobviousness, i.e., secondary considerations. Graham v. John Deere Co.,
383 U.S. 1, 17–18 (1966).
Additionally, the obviousness inquiry typically requires an analysis of
“whether there was an apparent reason to combine the known elements in
the fashion claimed by the patent at issue.” KSR, 550 U.S. at 418 (citing In
re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006) (requiring “articulated
reasoning with some rational underpinning to support the legal conclusion of
obviousness”)). Furthermore, Petitioner does not satisfy its burden of
proving obviousness by employing “mere conclusory statements,” but “must
instead articulate specific reasoning, based on evidence of record, to support
the legal conclusion of obviousness.” In re Magnum Oil Tools Int’l, Ltd.,
829 F.3d 1364, 1380 (Fed. Cir. 2016).
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B. Level of Ordinary Skill in the Art
Relying on Dr. Fair’s testimony, Petitioner asserts that a person of
ordinary skill in the art (“POSA”) would have had “a PhD in chemistry,
biochemistry, mechanical or electrical engineering, or a related discipline
with one year of experience related to systems for handling microfluidic
droplets,” “a Bachelor of Science in such fields with four years of such
experience,” or an equivalent level of education and practical experience.
Pet. 3; Ex. 1008 ¶ 47. Petitioner and Dr. Fair assert that a “POSA would
have knowledge of scientific literature concerning droplets (including
emulsions), and systems and methods for handling them (including both
their formation and handling downstream of formation), their applications,
and chemistry, components, and reactions that occur within them.” Pet. 3;
Ex. 1008 ¶ 47. In addition, Petitioner and Dr. Fair assert that a “POSA may
have worked on a multidisciplinary team and drawn on his or her own skills
along with certain specialized skills of others; and a chemist, engineer, and
biologist may have been part of the team.” Pet. 3; Ex. 1008 ¶ 47.
Relying on Dr. Anna’s testimony, Patent Owner asserts that a POSA
“would have had at least the equivalent of a Bachelor’s degree in
engineering, physics, or chemistry and two years of academic, research, or
industry experience related to fluid mechanics, fluid dynamics, or
microfluidics.” PO Resp. 17; Ex. 2016 ¶ 72. In addition, Patent Owner and
Dr. Anna assert that “[a]dditional training or study could substitute for work
experience and additional work experience or training could substitute for
formal education.” PO Resp. 17–18; Ex. 2016 ¶ 72.
Both sides’ declarants represent that their opinions would not change
based on their opponent’s articulation of the level of ordinary skill in the art.
Ex. 1071 ¶ 13; Ex. 2016 ¶ 74.
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We find that Patent Owner’s definition of a POSA is consistent with
the scope and content of the ’837 Patent and the asserted prior art. In
addition, we find that Patent Owner’s definition of a POSA is consistent
with the legal standard for obviousness, which is to be determined from the
viewpoint of a person of ordinary, not extraordinary, skill. Stewart-Warner
Corp. v. City of Pontiac, Mich., 767 F.2d 1563, 1570 (Fed. Cir. 1985)
(section 103 is not concerned with the actual skill of the inventors—whose
skill may be extraordinary—but rather with the level of ordinary skill in the
art).
In contrast, Dr. Fair’s opinion about the level of ordinary skill in the
art is based on his own experience working in the field and “working with
others in this field who consistently had that level of education and/or
experience and worked with a multidisciplinary team.” Ex. 1071 ¶ 10.
Dr. Fair considers himself “an expert in the art of biomedical microfluidics
and related applications, including handling microfluidic droplets.”
Ex. 1008 ¶ 48. We find that Petitioner and Dr. Fair have defined a POSA
based on the level of skill possessed by Dr. Fair and others like him who are
experts in the field. Ex. 1008 ¶¶ 47, 48; Ex. 1071 ¶¶ 9, 10. In our view, the
level of skill in the art proposed by Petitioner and Dr. Fair is more akin to
extraordinary, rather than ordinary skill in the art.
For these reasons, we apply Patent Owner’s definition of a POSA.
We also apply a portion of Petitioner’s definition, namely that a POSA
“would have knowledge of scientific literature concerning droplets
(including emulsions), and systems and methods for handling them
(including both their formation and handling downstream of formation),
their applications, and chemistry, components, and reactions that occur
within them.” Pet. 3; Ex. 1008 ¶ 47; Ex. 1071 ¶ 12. This portion is
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undisputed by Patent Owner and is consistent with the ’837 Patent and the
asserted prior art, as summarized below. In any event, our determinations
regarding Petitioner’s challenges do not turn on the differences between
Petitioner’s and Patent Owner’s definitions of a POSA, and our conclusion
would be the same under either party’s definition.
C. Claim Construction
In an inter partes review, we apply the same claim construction
standard as would be used by a district court to construe a claim in a civil
action involving the validity or infringement of a patent. 37 C.F.R.
§ 42.100(b). Under that standard, claim terms are given their ordinary and
customary meaning, as would have been understood by a person of ordinary
skill in the art at the time of the invention, in light of the language of the
claims, the specification, and the prosecution history of record. Id.; Phillips
v. AWH Corp., 415 F.3d 1303, 1312–19 (Fed. Cir. 2005) (en banc); Thorner
v. Sony Comput. Entm’t Am. LLC, 669 F.3d 1362, 1365–66 (Fed. Cir. 2012)
(unless a claim term has been expressly defined by the patentee or has been
limited by a clear and unmistakable disavowal of claim scope, it should
receive its ordinary meaning).
The Petition is based on alternative claim constructions, with some
grounds relying on Petitioner’s proposed constructions and other grounds
relying on constructions that Petitioner attributes to Patent Owner based on
Patent Owner’s infringement contentions in the related district court action.
Pet. 18–20, 24–25. In the Institution Decision, we rejected Petitioner’s
proposed constructions for two claim terms, “separation chamber” and
“droplet receiving outlet,” and we applied the constructions relied upon by
Patent Owner in its district court infringement contentions. Inst.
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Dec. 10–17. In the Response, Patent Owner proposes its own constructions
for these terms. PO Resp. 18, 22. In the Reply, Petitioner neither opposes
Patent Owner’s constructions, nor challenges our rejection of Petitioner’s
constructions. See Pet. Reply 2–3 (discussing Patent Owner’s
constructions).
Below we address the terms “separation chamber” and “droplet
receiving outlet.” We reject Petitioner’s constructions for essentially the
same reasons as set forth in the Institution Decision, and we adopt Patent
Owner’s constructions, which are unopposed by Petitioner. We determine
that no other claim term requires express construction for purposes of
resolving the controversy. See Vivid Techs., Inc. v. Am. Sci. & Eng’g, Inc.,
200 F.3d 795, 803 (Fed. Cir. 1999) (“only those terms need be construed that
are in controversy, and only to the extent necessary to resolve the
controversy”); see also Nidec Motor Corp. v. Zhongshan Broad Ocean
Motor Co., 868 F.3d 1013, 1017 (Fed. Cir. 2017) (applying Vivid Techs. in
the context of inter partes review).
1. “separation chamber”
Claim 1 recites that the claimed assembly comprises “at least one
downstream separation chamber.” Ex. 1001, 88:10. Claim 1 further recites
that the separation chamber “is of a volume sufficient to separate the
plurality of droplets comprising the sample from the immiscible fluid within
the separation chamber.” Id. at 88:18–23.
a) Petitioner’s Construction
Petitioner contends that “separation chamber” should be construed as
“a space that is substantially enclosed” and that a POSA “would not
understand the term ‘separation chamber’ to include open containers.”
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Pet. 19, 21–22. As support for this construction, Petitioner cites dictionaries
that define a “chamber” as an “enclosed space or cavity.” Pet. 21 (citing
Exs. 1027, 1028). Petitioner also cites the purpose of the ’837 Patent’s
invention to eliminate the risk of contamination by avoiding operator
handling of droplets. Id. (citing, e.g., Ex. 1001, 52:33–37). Petitioner
acknowledges the Specification’s disclosure that a chamber can “include
any vessel suitable for holding droplets, for example, test tubes, vials,
beakers, jars, and PCR tubes,” but argues that such chambers “are
consistently and exclusively enclosed—not open—when in use with a ‘seal’
to ‘minimize potential contamination.’” Id. (quoting Ex. 1001, 53:45–47,
55:64–56:7 (emphasis added by Petitioner) and citing id. at Fig. 39).
We determine that Petitioner’s proposed construction that excludes
open containers is inconsistent with how the term “chamber” is used in the
Specification. The Specification states “[i]t is to be understood that the
chamber can include any vessel suitable for holding droplets, for example,
test tubes, vials, beakers, jars, and PCR tubes.” Ex. 1001, 53:35–38
(emphasis added). As Petitioner’s argument acknowledges, the disclosed
examples—test tubes, vials, beakers, jars, and PCR tubes—are all open
vessels, unless and until they are closed by a seal or other closure. See
Pet. 21 (stating the vessels are enclosed “when in use with a ‘seal’”).
Although Petitioner directs us to the description of vessel 903 that is
sealably connected to the assembly (id. (citing Ex. 1001, 55:55–65,
Fig. 39)), the cited portion of the Specification is merely a description of a
preferred embodiment that does not limit the scope of the claims. Moreover,
the cited description does not limit the meaning of “chamber” to an
“enclosed” space because vessel 903, within which oil is separated from
droplets due to density differences, refers to the vessel alone, without the
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cap that seals it to the assembly. Ex. 1001, 55:60–62 (“In certain
embodiments, the assembly includes a PCR tube cap 904 that lock[s] the
vessel 903 into a sealed position.”); see also id. at 57:38–41 (stating “vessels
for use with the invention may be sealed. For example, the lid to a PCR
tube . . . may be closed to prevent contamination” (emphasis added)).
Interpreting “chamber” as not requiring a space that is substantially
closed and not excluding an open container is also consistent with the
structure of the claims. Claim 1 recites a “separation chamber
comprising . . . at least one droplet receiving outlet.” Ex. 1001, 88:10–12.
Claim 7 depends from claim 1 and recites: “the droplet receiving outlet is
coupled to a vessel,” and claim 8 depends from claim 7 and recites that “the
droplet receiving outlet is sealably coupled to a vessel.” Id. at 88:40–43.
The subject matter of claim 1 is necessarily broader than the subject matter
of dependent claims 7 and 8 and is not limited to a separation chamber that
is closed by being sealably coupled to a vessel.
Accordingly, for these reasons, we do not adopt Petitioner’s proposed
construction for “separation chamber” as “a space that is substantially
enclosed.”
b) Patent Owner’s Construction
Consistent with its position in district court, Patent Owner argues that
“separation chamber” should be construed as a “chamber sized to
accommodate multiple droplets and an immiscible fluid in separated form.”
PO Resp. 18 (citing Ex. 2032 (Joint Claim Construction Chart filed in
district court)).
We find that Patent Owner’s construction is supported by claim 1’s
recitation that the separation chamber “is of a volume sufficient to separate
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the plurality of droplets comprising the sample from the immiscible fluid
within the separation chamber.” Ex. 1001, 88:18–23.
We find that the Specification supports Patent Owner’s construction
for “separation chamber.” The Specification discloses that partitioned
portions, i.e. droplets, and immiscible fluid flow into a chamber, where the
partitioned portions sink, float, or are displaced from the chamber as a result
of a difference in density between the partitioned portions and the
immiscible fluid. Ex. 1001, 2:45–50, 3:37–46. Patent Owner’s construction
is further supported by the Specification’s description of a “chamber . . .
configured to receive droplets and an immiscible fluid from the droplet
formation module,” where “the immiscible fluid displaces the droplet from
the chamber into the outlet due to the difference in density.” Id.
at 53:22–28. Patent Owner’s construction is consistent with the
Specification’s disclosure that “the chamber can include any vessel suitable
for holding droplets, for example, test tubes, vials, beakers, jars, and PCR
tubes.” Id. at 53:35–38.
We find that the prosecution history also supports Patent Owner’s
construction. Specifically, when distinguishing the “separation chamber”
from a “conduit” disclosed in the prior art, Applicant argued that the conduit
“accommodates only one droplet across its width at a time,” whereas “the
width of the claimed chamber is sized to accommodate multiple droplets,
which allows for droplet concentration and removal of carrier fluid from
between the droplets.” Ex. 1002, 1114; see also id. at 1110 (amended
claim 1: “the chamber has a width that is sized to accumulate a plurality of
droplets across the width”). Similarly, Applicant distinguished the
“separation chamber” of the claims from a “cross-intersection” disclosed in
the prior art, arguing that the cross-intersection “is not a vertical chamber to
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separate droplets from an immiscible carrier fluid” and does not “have a
wider cross-intersection [sic, cross-section] than the channel cross-section to
accumulate droplets in an immiscible fluid or have a specific volume to
separate droplets from an immiscible fluid.” Id. at 1168–69; see also id.
at 1165 (amended claim 1: “the separation chamber is vertical to the
channel” and “the separation chamber has a wider cross-section than the
channel cross-section to accumulate a plurality of droplets and is of a
volume sufficient to separate the plurality of droplets from an immiscible
fluid.”).
For these reasons, we adopt Patent Owner’s proposed construction
that “separation chamber” means “chamber sized to accommodate multiple
droplets and an immiscible fluid in separated form.”
2. “droplet receiving outlet”
Claim 1 recites that the separation chamber comprises “a droplet
receiving chamber inlet and at least one droplet receiving outlet.”
Ex. 1001, 88:10–12.
a) Petitioner’s Constructions
Petitioner first contends that “droplet receiving outlet” should be
construed as a means-plus-function limitation pursuant to 35 U.S.C.
§ 112(f).7 Pet. 18, 20. Petitioner next contends that, if the term is not
subject to § 112(f), then a “droplet receiving outlet” should be construed as
“a structure connected to the interior space of the chamber and configured so

7 Although Petitioner refers to the post-AIA version of the statute (35 U.S.C.
§ 112(f)) and the case law discussed herein addresses the pre-AIA version of
the statute (35 U.S.C. § 112 ¶ 6), the same principles apply under both
versions of the statute.
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that substantially only droplets flow into it when exiting the chamber.”
Pet. 18–19. As support for its constructions, Petitioner argues that “‘droplet
receiving outlet’ . . . is not in the specification and has no well-understood
meaning in the art.” Pet. 20 (citing Ex. 1008 ¶ 80). In addition, Petitioner
argues that the term is “described in functional terms” both in the claims and
the Specification. Id. (citing Ex. 1001, code (57), 3:46–58, 53:21–35).
We first address Petitioner’s contention that a “droplet receiving
outlet” should be construed as a means-plus-function limitation. Under
applicable law, if a claim term lacks the word “means,” there is a rebuttable
presumption that the term is not subject to 35 U.S.C. § 112(f) or § 112 ¶ 6.
MTD Prod. Inc. v. Iancu, 933 F.3d 1336, 1341 (Fed. Cir. 2019); Williamson
v. Citrix Online, LLC, 792 F.3d 1339, 1348 (Fed. Cir. 2015) (en banc). A
challenger can rebut the presumption by demonstrating that “the claim term
fails to recite sufficiently definite structure or else recites function without
reciting sufficient structure for performing that function.” Williamson, 792
F.3d at 1348 (internal quotes, brackets, and citation omitted). “One way to
demonstrate that a claim limitation fails to recite sufficiently definite
structure is to show that, although not employing the word ‘means,’ the
claim limitation uses a similar nonce word that can operate as a substitute for
‘means’ in the context of § 112, para. 6.” MTD, 933 F.3d at 1341 (internal
quotes omitted); Williamson, 792 F.3d at 1350.
Here, the disputed claim term is “droplet receiving outlet.” Because
the term does not recite the word “means,” there is a rebuttable presumption
that it is not a means-plus-function term. We find that Petitioner has not
rebutted that presumption. Petitioner’s arguments and evidence do not
persuade us that “droplet receiving outlet” fails to recite sufficiently definite
structure. Petitioner does not argue that “outlet” is a “nonce word that can
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operate as a substitute for ‘means’” in the context of a patent claim.
Williams, 792 F.3d at 1350. In our view, “outlet” is not a generic term, like
“module,” “mechanism,” “element,” or “device,” that is commonly used as a
verbal construct to claim a particular function rather than to describe a
sufficiently definite structure. Cf. MTD, 933 F.3d at 1341.
The surrounding claim language suggests that a “droplet receiving
outlet” is structural. Claim 1 recites “at least one downstream separation
chamber comprising a droplet receiving chamber inlet and at least one
droplet receiving outlet.” Ex. 1001, 88:10–12. Despite the linguistic
similarity of a “droplet receiving chamber inlet” and a “droplet receiving
outlet,” Petitioner makes no argument that the former term should be
construed as a means-plus-function term. The dependent claims also suggest
that § 112(f) (or pre-AIA § 112 ¶ 6) does not apply. Claim 3 recites that the
droplet receiving outlet “is located on the lower portion of the separation
chamber,” claim 4 recites that the droplet receiving outlet “is located on the
upper portion of the separation chamber,” and claim 5 recites that the droplet
receiving outlet “is connected to a proximal end of a slide.” Ex. 1001,
88:27–35. Petitioner does not dispute that a “separation chamber” and a
“slide” are structural limitations. We find that the surrounding language of
claim 1 and the added limitations of dependent claims 3–5 support the
structural nature of a “droplet receiving outlet” and do not help rebut the
presumption against application of § 112(f) to this non-means term. See
TEK Global, S.R.L. v. Sealant Sys. Int’l, Inc., 920 F.3d 777, 785–86 (Fed.
Cir. 2019) (relying on surrounding claim language and limitation of
dependent claim when determining that “conduit” is not a means-plus-
function term).
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Although Dr. Fair opines that a POSA “would consider the term
‘droplet receiving outlet’ not to be a term used by persons of skill in the art
to designate either a particular structure or a class of structures,” he cites no
persuasive evidence to support that opinion. Ex. 1008 ¶ 80. We find that
Dr. Fair’s opinion is undermined by his concession that a POSA “is familiar
with numerous outlet structures.” Id. Moreover, Dr. Fair refers to the term
“outlet” as having a definite structure. See id. ¶ 81 (stating “the
corresponding structure are the outlets”). In our view, “outlet” is not a
nonce word, and the term “droplet receiving outlet” conveys sufficiently
definite structure and is not subject to AIA 35 U.S.C. § 112(f) or pre-AIA
§ 112 ¶ 6.
We also reject Petitioner’s argument that “droplet receiving outlet”
should be construed as requiring that “substantially only droplets” exit the
chamber through the outlet. Pet. 18–21. Petitioner directs us to several
Specification passages that describe a chamber outlet in this manner. Pet. 20
(quoting Ex. 1001, code (57), 3:46–48, 53:24–25, 53:32–35, and citing
53:21–41, 54:34–46, 55:41–44). Petitioner provides no justification,
however, for reading these descriptions from the Specification into the
claim. Thorner, 669 F.3d at 1365–66 (absent an express definition or clear
and unmistakable disavowal, claim terms should receive their ordinary
meaning). Moreover, the Specification describes outlet 805, which is shown
in Figure 38, as positioned where the rising droplets will exit chamber 804
into outlet 805 and “leav[e] a large part of the oil behind.” Ex. 1001,
54:41–44. Because the Specification states that a “large part of the oil” is
left behind, it can be presumed that at least part of the oil exits chamber 804
into outlet 805 with the droplets. Id.
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Furthermore, Petitioner’s proposed construction requiring that
“substantially only droplets” exit the chamber through the outlet is
inconsistent with dependent claim 10, which depends from claim 1 and
recites: “wherein the droplet receiving outlet receives substantially one or
more droplets.” Ex. 1001, 88:46–47. Dependent claim 10 describes the
function of the “droplet receiving outlet” in a manner similar to Petitioner’s
proposed construction, except that the word “only” is conspicuously missing
from claim 10. As a matter of law, we cannot construe independent claim 1
more narrowly than dependent claim 10. 35 U.S.C. § 112(d) (corresponding
to pre-AIA § 112 ¶ 4); Trustees of Columbia Univ. v. Symantec Corp., 811
F.3d 1359, 1370 (Fed. Cir. 2016) (“[W]here dependent claims have no
meaningful difference other than an added limitation, . . . construing the
independent claim to exclude material covered by the dependent claim
would be inconsistent.”).
Accordingly, for these reasons, we do not adopt either of Petitioner’s
proposed constructions for “droplet receiving outlet.”
b) Patent Owner’s Construction
Consistent with its position in district court, Patent Owner argues that
“droplet receiving outlet” should be construed as a “portion of the separation
chamber where droplets are collected.” PO Resp. 22 (citing Ex. 2032).
We find that the Specification supports Patent Owner’s interpretation
that a “droplet receiving outlet” is a “portion of the separation chamber.”
The Specification discloses that “[t]he chamber includes an outlet that is
positioned to receive substantially only the partitioned portions of sample.”
Ex. 1001, 3:46-48. In addition, the Specification discloses that the outlet
may positioned be “at the top, middle, or bottom of the chamber” depending
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on the densities of the partitioned portions and the immiscible fluid. Id.
at 3:48–52. For example, the Specification states that the outlet is positioned
in a top portion of the chamber if the immiscible fluid is of a greater density
than the partitioned portions, such that the partitioned portions rise in the
chamber while the immiscible fluid sinks and the partitioned portions flow
into the outlet. Id. at 3:52–58. These portions of the Specification show that
a “droplet receiving outlet” is a portion of the separation chamber.
We find that the Specification also supports Patent Owner’s
interpretation that a “droplet receiving outlet” is a “where droplets are
collected.” For example, the Specification discloses that aqueous droplets
tend to rise when placed in a chamber of fluorinated oil, and accordingly,
“an outlet for collecting the displaced droplets can be positioned at the top of
the chamber.” Ex. 1001, 4:8–12. In another example, the Specification
discloses that aqueous droplets tend to sink when placed in a chamber of
certain mineral oils, and accordingly, “an outlet for collecting the displaced
droplets can be positioned at the bottom of the chamber.” Id. at 4:12–16.
Both of these examples illustrate the role of an outlet as a structure for
collecting droplets.
We find that Patent Owner’s claim construction is supported by the
Specification’s description of Figure 38. The Specification states that “a
chamber 804 equipped with an outlet 805” and “the outlet 805 can be
positioned at an upper portion of the chamber 804 where the rising droplet
will exit the chamber 804 into the outlet 805” or “the outlet 805 [can be]
positioned at a lower portion of the chamber 804.” Ex. 1001, 54:34–35,
54:41–46. When describing the Figure 38 embodiment, the Specification
states that outlet 805 is positioned at the top of chamber 804 to collect
droplets that are displaced by oil flowing into the chamber and that rise to
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the top of the chamber. Id. at 59:55–63. These descriptions are consistent
with Patent Owner’s proposed construction for “droplet receiving outlet.”
For these reasons, we adopt Patent Owner’s proposed construction
that a “droplet receiving outlet” means a “portion of the separation chamber
where droplets are collected.”
D. Petitioner’s Ground 1: Ismagilov 091 Anticipation
Petitioner contends that Ismagilov 091 anticipates claims 1, 2, 4, 10–
13, 19, and 20 of the ’837 Patent. Pet. 31–56. We first provide an overview
of Ismagilov 091 and then discuss the claims challenged in this ground.
1. Ismagilov 091 (Ex. 1004)
Ismagilov 091 is a U.S. Patent titled “Device and Method for
Pressure-Driven Plug Transport and Reaction.” Ex. 1004, codes (10), (54).
Petitioner asserts that Ismagilov 091 is prior art to the ’837 Patent under
35 U.S.C. § 102(a)(2) and pre-AIA § 102(e) as of its May 9, 2003 filing date
and under § 102(a)(1) and pre-AIA § 102(a) as of its December 8, 2005
publication date. Pet. 12–13. Petitioner contends that Ismagilov 091 is prior
art under pre-AIA § 102(b), if the challenged claims are not entitled to the
benefit of any provisional applications filed between May 11, 2006 and
December 12, 2006. Pet. 13, 15–16.
Patent Owner does not contest the prior art status of Ismagilov 091.
We do not need to address Petitioner’s contention under pre-AIA § 102(b)
because Patent Owner does not attempt to show a date of invention earlier
than Ismagilov 091’s filing date or publication date. We find that
Ismagilov 091 is prior art to the ’837 Patent, regardless of whether the AIA
applies to the patent.
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Ismagilov 091 discloses microfabricated substrates and methods of
conducting reactions in droplets (“plugs”) in a flow of carrier fluid in a
substrate. Ex. 1004, code (57).
Ismagilov 091 discloses that “‘[p]lugs’ . . . are formed in a substrate
when a stream of at least one plug-fluid is introduced into the flow of a
carrier-fluid in which it is substantially immiscible.” Ex. 1004, 9:20–23.
According to Ismagilov 091, the “plugs” may be in the form of “an aqueous
plug-fluid . . . surrounded by a non-polar or hydrophobic fluid such as an
oil.” Id. at 9:39–44. Ismagilov 091 discloses that an “inlet port” is “an area
of a substrate that receives plug-fluids,” and “[t]he inlet port can be in fluid
communication with a channel.” Id. at 8:41–42, 8:46–47. According to
Ismagilov 091, a “channel” includes “microchannels.” Id. at 7:46–48.
Ismagilov 091 discloses that an “outlet port” is “an area of a substrate that
collects or dispenses the plug-fluid, carrier-fluid, plugs or reaction product.”
Id. at 9:5–8.
In a section headed “Channels and Devices,” Ismagilov 091 discloses
a device that “includes one or more substrates comprising a first channel
comprising an inlet separated from an outlet.” Ex. 1004, 14:20–23.
According to Ismagilov 091,
The device may have one or more outlet ports or inlet ports. Each
of the outlet and inlet ports may also communicate with a well or
reservoir. The inlet and outlet ports may be in fluid
communication with the channels or reservoirs that they are
connecting or may contain one or more valves.
Id. at 14:36–40. In this section, Ismagilov 091 also discloses that a “plug-
forming region generally comprises a junction between a plug-fluid inlet and
a channel containing the carrier-fluid such that plugs form.” Id. at 14:44–45.
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In a section headed “Fabrication of Channels, Substrates, and
Devices,” Ismagilov 091 discloses methods for fabricating microfluidic
devices, including a polymer casting method. Ex. 1004, 16:1–7, 16:23–41.
According to this method, a negative image of the channels is etched into a
crystalline silicon wafer, and the wafer is used as a mold for casting the
channels from polydimethylsiloxane (PDMS). Id. at 16:23–28. In this
method, the silicon wafer mold is placed in the bottom of a Petri dish,
uncured PDMS is poured onto the mold, and the PDMS is then cured and
removed from the mold. Id. at 16:30–35. Ismagilov 091 discloses that
“[h]oles may be cut into the PDMS using, for example, a tool such as a cork
borer or a syringe needle.” Id. at 16:35–36. According to Ismagilov 091,
the PDMS channels are treated with hydrochloric acid to render the surface
hydrophilic. Id. at 16:37–38. Ismagilov 091 discloses that the PDMS
channels can be “placed onto a microscope cover slip (or any other suitable
flat surface), which can be used to form the base/floor or top of the
channels.” Id. at 16:38–41.
Ismagilov 091 discloses that “[a] substrate containing the fabricated
flow channels and other components is preferably covered and sealed,
preferably with a transparent cover, e.g., thin glass or quartz, although other
clear or opaque cover materials may be used.” Ex. 1004, 16:60–64.
According to Ismagilov 091, the substrate can include “[a] variety of
channels for sample flow” as well as “manifolds (a region consisting of
several channels that lead to or from a common channel).” Id. at 17:10–11,
17:18–20. Such manifolds can “route[] the flow of solution to an outlet.”
Id. at 17:23–27. Ismagilov 091 discloses that “[t]he outlet can be adapted
for receiving, for example, a segment of tubing or a sample tube, such as a
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standard 1.5 ml centrifuge tube. Collection can also be done using
micropipettes.” Id. at 17:27–30.
Figure 3A of Ismagilov 091 is reproduced below.

Ismagilov 091 Figure 3A includes a photograph (right side) and a schematic
diagram (left side) depicting a stream of plugs formed from an aqueous
plug-fluid and an oil (carrier-fluid) in curved serpentine channels. Ex. 1004,
4:6–10, 18:24–26, Fig. 3A. According to Ismagilov 091, the carrier-fluid is
introduced into inlet port 300 of a substrate, and three aqueous plug-fluids
are introduced in separate inlet ports 301, 302, and 303. Id. at 18:31–33.
2. Independent Claim 1
a) Element 1.0
It is undisputed that Ismagilov 091 discloses “an assembly” as recited
in the preamble of claim 1. We find that Ismagilov 091 discloses
“microsubstrates” that are, or are part of, an assembly, as Petitioner
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contends. Pet. 31; Ex. 1004, code (57). Ismagilov 091 discloses that
microfluidic substrates may be part of an assembly that includes, for
example, syringe pumps, a microscope, a light source, a detector, a
processor, a display monitor, and a printer. Ex. 1004, 14:42–43, 30:2–4,
31:20–27, 32:10–15, 32:60–63, 33:4–7, 33:25–35.
b) Element 1.1
There is no dispute that Ismagilov 091 discloses “a microchannel in a
horizontal plane” as recited in claim element 1.1. We find that
Ismagilov 091 discloses microchannels. For example, Ismagilov 091
discloses that “the term ‘channel’ includes microchannels that are of
dimensions suitable for use in devices.” Ex. 1004, 7:46–48; see also id.
at 62:1–4 (“Example 3[;] Networks of microchannels with rectangular cross-
sections were fabricated using rapid prototyping in PDMS.”).
We find that Ismagilov 091’s microchannels are in a horizontal plane.
Our finding is supported by Ismagilov 091, which discloses that molded
PDMS channels can be “placed onto a microscope cover slip (or any other
suitable flat surface), which can be used to form the base/floor or top of the
channels.” Ex. 1004, 16:38–41; see also id. at 16:60–63 (“A substrate
containing the fabricated flow channels and other components is preferably
covered and sealed, preferably with a transparent cover, e.g., thin glass or
quartz, although other clear or opaque cover materials may be used.”).
Petitioner shows persuasively that, when a glass cover slip is used as the
“floor . . . of the channels,” as Ismagilov 091 discloses, then a substrate
containing the fabricated flow channels is placed channel-side down onto the
cover slip, with the channels running parallel to the cover slip, i.e.,
horizontally. Pet. 31–32; Ex. 1004, 16:38–41.
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c) Element 1.2
It is undisputed that Ismagilov 091 discloses claim element 1.2, which
recites:
at least one droplet formation module comprising a sample inlet,
an immiscible fluid inlet, and a junction, wherein the junction is
located between the sample inlet and the microchannel and the
droplet formation module is configured to produce droplets
comprising the sample surrounded by the immiscible fluid.
Ex. 1001, 88:4–9.
We find that Ismagilov 091 discloses a “droplet formation module”
(Ismagilov 091’s “plug-forming region”) comprising a “sample inlet”
(Ismagilov 091’s “plug-fluid inlet” or “sample inlet”), an “immiscible fluid
inlet” (Ismagilov 091’s “carrier-fluid inlet,” where the carrier-fluid is “a
fluid that is immiscible with a plug-fluid”), and a “junction”
(Ismagilov 091’s “junction between a plug-fluid inlet and a channel
containing the carrier-fluid”). Pet. 32; Ex. 1004, 7:31–32, 14:44–61,
15:53–60.
We find that Ismagilov 091 teaches “the junction is located between
the sample inlet and the microchannel” as recited in claim element 1.2. For
example, Ismagilov 091 discloses that a “plug-forming region generally
comprises a junction between a plug-fluid inlet and a channel containing the
carrier-fluid.” Ex. 1004, 14:44–46.
We find that Ismagilov 091 discloses that “the droplet formation
module is configured to produce droplets comprising the sample surrounded
by the immiscible fluid” as recited in claim element 1.2. For example,
Ismagilov 091 discloses that plugs “are formed in a substrate when a stream
of at least one plug-fluid is introduced into the flow of a carrier-fluid in
which it is substantially immiscible.” Ex. 1004, 9:20–23; see also id.
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at 9:39–41 (“The plugs may be in the form of plugs comprising an aqueous
plug-fluid containing one or more reagents . . . .”); id. at 14:44–49 (“A plug-
forming region generally comprises a junction between a plug-fluid inlet and
a channel containing the carrier-fluid such that plugs form . . . .”).
d) Element 1.3
Claim element 1.3 recites: “at least one downstream separation
chamber comprising a droplet receiving chamber inlet and at least one
droplet receiving outlet.” Ex. 1001, 88:10–12.
Petitioner contends that Ismagilov 091 discloses claim element 1.3
under an interpretation of “separation chamber” and “droplet receiving
outlet” that Petitioner attributes to Patent Owner based on its infringement
contentions. Pet. 35–36 (citing Ex. 1026, 11). Petitioner also contends that
Ismagilov 091 discloses claim element 1.3 under Patent Owner’s
constructions as presented in the Response. Pet. Reply 4. Petitioner asserts
that these constructions are “broad enough to encompass an open well and
the opening at the top of an open outlet well.” Pet. 35; Pet. Reply 2.
Petitioner contends that Ismagilov 091 discloses “at least one
downstream separation chamber” in the form of a collection well or
reservoir and that Ismagilov 091 discloses a “droplet receiving chamber
inlet” in the form of an outlet of a manifold. Pet. 36 (citing Ex. 1004, 9:5–8,
14:36–40, 17:27–30). Petitioner asserts that Ismagilov 091 discloses a
“droplet receiving outlet” by describing “a well or reservoir with an opening
at the top” and “the ability to collect the fluids by micropipette.” Pet. 36–37.
Patent Owner argues that Ismagilov 091 does not disclose a
“separation chamber” or a “droplet receiving outlet.” PO Resp. 29–38.
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After considering Patent Owner’s arguments and evidence, we find
that Petitioner shows persuasively that Ismagilov 091 discloses a collection
well or reservoir8 at the outlet of a microfluidic device. Pet. 36. Our finding
is supported by Ismagilov 091’s definition of an “outlet port” as “an area of
a substrate that collects . . . plugs” and Ismagilov 091’s disclosure that the
outlet port may “communicate with a well or reservoir.” Ex. 1004, 9:5–8,
14:37–38. Taken together, these two disclosures plainly convey that
Ismagilov 091’s device may include an outlet well or reservoir for collecting
droplets (plugs).
We find that Petitioner shows persuasively that Ismagilov 091’s
collection well or reservoir (corresponding to the claimed “separation
chamber”) is located downstream of Ismagilov 091’s plug-forming region
(corresponding to the claimed “droplet formation module”). Pet. 37. Our
finding is supported by Ismagilov 091, which discloses that plugs flow from
the plug-forming region through a channel to an outlet port, which may
include a well or reservoir for collecting plugs. Ex. 1004, 9:5–8, 14:20–22,
14:36–40, 21:48–54; see also id. at 8:12–14 (defining “downstream” as “a
position relative to an initial position which is reached after the fluid flows
past the initial point”).
We find that Petitioner shows persuasively that Ismagilov 091
describes a collection well that allows for collection of droplets using a
micropipette. Pet. 36. Our finding is supported by Ismagilov 091’s
description of a “manifold” as “a region consisting of several channels that
lead to or from a common channel,” such that the manifold “facilitate[s] the

8 In this Decision, we use the term “collection well” and “outlet well”
interchangeably to refer to a well that collects droplets and is located at the
outlet of a microfluidic device.
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movement of plugs from different analysis units” and “routes the flow of
solution to an outlet.” Ex. 1004, 17:18–27. According to Ismagilov 091,
“The outlet can be adapted for receiving, for example, a segment of tubing
or a sample tube, such as a standard 1.5 ml centrifuge tube. Collection can
also be done using micropipettes.” Id. at 17:27–30. We are persuaded by
Petitioner’s contention that Ismagilov 091’s disclosure of “[c]ollection . . .
using micropipettes” refers to collecting droplets from a well using a
micropipette. Id.; Pet. 36–37.
Our finding is supported by Dr. Fair’s testimony, as follows:
To permit the collection of fluids by micropipette, there
must be a container with a volume of liquid that can be pipetted,
and an opening into which the micropipette can be inserted,
which describes a collection well.
Ex. 1008 ¶ 130 (citing Exs. 1040, 1041 as providing information about
micropipettes).9
[F]or a micropipette to be able to collect liquid, the liquid
must first be collected in a container that (1) is of a sufficient
volume for the pipette tip to be inserted, (2) has an opening
through which the pipette can be inserted, and (3) the liquid is of
a sufficient volume that the micropipette can collect it. This
describes a collection well.
Id. ¶ 131. Our finding is further supported by Dr. Fair’s testimony that
“Ismagilov 091 also confirms there is an opening in the manifold outlet well
by describing the ability to collect the fluids by micropipette.” Id. ¶ 134
(citing Ex. 1004, 17:27–30).

9 Exhibit 1040 is a Rainin Classic datasheet for “continuously adjustable
digital microliter pipettes,” and Exhibit 1041 is a web page titled, “Resource
Materials: Use of Micropipetes [sic].”
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We are persuaded that Ismagilov 091’s collection wells or reservoirs
satisfy our claim construction for “separation chamber” and “droplet
receiving outlet.” As discussed above, we adopt Patent Owner’s proposed
construction of “separation chamber” as meaning a “chamber sized to
accommodate multiple droplets and an immiscible fluid in separated form.”
We adopt Patent Owner’s proposed construction of “droplet receiving
outlet” as meaning a “portion of the separation chamber where droplets are
collected.”
Petitioner shows persuasively that Ismagilov 091 teaches a collection
well or reservoir sized to accommodate multiple droplets and immiscible
fluid.10 Pet. 36, 41. More specifically, Petitioner provides persuasive
evidence that Ismagilov 091 teaches a well or reservoir large enough to
allow collection of fluid by micropipette, which means that the well or
reservoir has a volume greater than 0.1 μl. Pet. 41 (citing Ex. 1004, 17:27–
30; Exs. 1040, 1041). Petitioner shows that a well or reservoir with a
volume greater than 0.1 μl would accommodate multiple droplets of the size
disclosed by Ismagilov 091. Id.; Ex. 1004, 19:61–64 (disclosing “plug
volumes of between about 16 picoliters (pL) to 16 nanoliters (nL)”). Our
findings are supported by the cited disclosures of Ismagilov 091, the sizes of
commercially available micropipettes as shown in Exhibits 1040 and 1041,
and Dr. Fair’s testimony concerning the minimum volume that can be
collected by micropipette compared with the volume of droplets disclosed in
Ismagilov 091. Ex. 1008 ¶ 161 (citing Ex. 1004, 17:27–30, 19:61–66;

10 The issue of whether Ismagilov 091’s well or reservoir has a volume
sufficient to separate the droplets from the immiscible fluid within the
separation chamber such that the droplets and immiscible fluid are “in
separated form” is addressed below in connection with claim element 1.7.
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Exs. 1040, 1041). We observe that, even if the volume of Ismagilov 091’s
outlet well were only 0.1 μl, it would still be large enough to accommodate
2500 16 pL droplets and 0.06 μl of immiscible fluid. We also credit
Dr. Fair’s testimony that, to allow collection by micropipette, “the well will
need to be larger than the 0.1 μl minimum volume that a micropipette can
collect.” Id.
Petitioner also shows persuasively that Ismagilov 091 teaches a
collection well or reservoir that is open at the top to allow a micropipette to
be inserted for the purpose of collecting droplets. Pet. 36–37; Ex. 1008
¶¶ 129–131, 134. Patent Owner does not dispute that such an open top
satisfies our claim construction for “droplet receiving outlet.” See generally
PO Resp. 24–25, 35–37.
Patent Owner argues that “Petitioner improperly attempts to piece
together the disclosure of a ‘separation chamber’ using multiple disparate
sections in Ismagilov that do not clearly connect to one another in any
discernable arrangement or configuration that would be considered a
‘separation chamber.’” PO Resp. 29; see also id. at 29–32 (elaborating on
the separateness of Ismagilov 091’s disclosures cited by Petitioner). We
disagree. We are persuaded that Petitioner interprets Ismagilov 091 from the
perspective of a POSA without mixing and matching unrelated disclosures,
as asserted by Patent Owner. Id. at 34. Although Petitioner relies on
disclosures from separate sections of Ismagilov 091, we find a POSA would
understand that the cited disclosures all relate to an outlet or outlet port and
can fairly be read together as disclosing that the outlet port may
communicate with a well or reservoir for collecting droplets, where the well
or reservoir allows for collection of the droplets using a micropipette.
Ex. 1004, 9:5–8 (defining “outlet port” as “an area of a substrate that collects
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. . . plugs . . . .”); id. at 14:37–38 (“Each of the outlet and inlet ports may
also communicate with a well or reservoir . . . .”); 17:27–30 (“The outlet can
be adapted for . . . [c]ollection . . . using micropipettes.”).
Patent Owner disputes Petitioner’s interpretation of Ismagilov 091’s
column 17 disclosure, arguing that “the ‘outlet ports’ of Ismagilov typically
act as conduits that allow for collection of the entirety of the ‘solution’
outside of the device.” PO Resp. 32–33 (citing Ex. 2016 ¶ 129); see also id.
at 34 (“the only functionality disclosed for the ‘outlet ports’ is solution
extraction” (citing Ex. 2016 ¶ 133)). In our view, however, the explanation
provided by Patent Owner and Dr. Anna may be consistent with
Ismagilov 091’s disclosure that “[t]he outlet can be adapted for receiving,
for example, a segment of tubing or a sample tube,” but does not adequately
account for the immediately succeeding disclosure that “[c]ollection can also
be done using micropipettes.” Ex. 1004, 17:27–30. Although Patent Owner
and Dr. Anna cite Exhibits 2020 and 2021 to show how a POSA would have
understood Ismagilov 091, they fail to direct us to any specific disclosures in
these references. PO Resp. 34; Ex. 2016 ¶ 134 (citing Exs. 2020,11 202112).

11 Ex. 2020, B. Zheng et al., Using Nanoliter Plugs in Microfluidics to
Facilitate and Understand Protein Crystallization, 15 Current Opinion in
Structural Biology 548 (2005). Figure 2(b) shows “Two funnel-shaped glass
capillaries are used to couple the cartridge to the inlet and the receiving
capillary to the outlet of the microfluidic channel.” Id. at 550. Figure 3(b)
shows “The receiving capillary is inserted into the outlet channel.” Id. at
551.
12 Ex. 2021, US 6,613,513 B1, issued Sept. 2, 2003, discloses microfluidic
systems in which “a ‘pipettor channel’ (a channel in which components can
be moved from a source to a microscale element such as a second channel or
reservoir) is temporarily or permanently coupled to a source of material.
The source can be internal or external to a microfluidic device comprising
the pipettor channel.” Id. at 32:47–52. Figure 2 shows an integrated system,
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In our view, neither reference is pertinent to Ismagilov 091’s disclosure of
an “outlet . . . adapted for . . . [c]ollection . . . using micropipettes.”
Ex. 1004, 17:27–30.
We credit Dr. Fair’s testimony that Ismagilov 091’s disclosure of
“[c]ollection . . . using micropipettes” describes an open-topped collection
well. Ex. 1008 ¶¶ 130, 131, 134. Although Patent Owner relies on
Dr. Fair’s deposition testimony that he has not personally used a pipette to
remove a droplet from a chip (PO Resp. 33–34 (quoting Ex. 2017,
43:9–16)), that testimony does not refute Ismagilov 091’s express disclosure
that “[c]ollection can also be done using micropipettes” (Ex. 1004, 17:27–
30), nor undermine Dr. Fair’s opinion that collection by micropipette
requires an open-topped collection well (Ex. 1008 ¶¶ 130, 131, 134). We
agree with Petitioner that Dr. Fair’s testimony shows sufficient familiarity
with the industry practice of using micropipettes to remove droplets from
wells to provide an adequate basis for this opinion. Pet. Reply 7 n.2 (citing
Ex. 1008 ¶¶ 130, 131, 160, 161, 170, 186; Ex. 2017, 42:21–43:4,
140:21–142:2).
Patent Owner argues that Ismagilov 091’s “outlet ports” or “wells or
reservoirs” differ from the “separation chamber” Patent Owner identifies in
the accused products. PO Resp. 2–3, 35–36. In our view, however, Patent
Owner’s arguments reinforce, rather than refute, Petitioner’s position that
Ismagilov 091 discloses collection wells. Patent Owner asserts that the ports
and outlets disclosed in Ismagilov 091 “would have been fabricated by
‘punching’ holes in the microchip itself at the channel ends, as was standard

including body structure 202 with reservoirs 204, 208, and 214 and main
channel 210, where reactants are flowed from pipettor channel 220 into main
channel toward reservoir 214. Id. at 35:50–61, Fig. 2.
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practice at the time.” PO Resp. 2; see also id. at 9 (similar assertion). Patent
Owner and Dr. Anna assert that “[t]o create inlets and outlets, it was
common at the time to punch a hole through the PDMS at the ends of the
channels where fluid was desired to be introduced and to exit.” Id. at 16;
Ex. 2016 ¶ 68 (citing Ex. 203313). Patent Owner and Dr. Anna equate
Ismagilov 091’s “outlet ports” or “wells or reservoirs” with the “[h]oles”
that Ismagilov 091 states “may be cut into the PDMS [substrate] using, for
example, a tool such as a cork borer or a syringe needle,” asserting that such
“‘hole punches’ . . . would have been well known to a POSA at the time.”
PO Resp. 36 (quoting Ex. 1004, 16:35–36); Ex. 2016 ¶¶ 35, 137.
The evidence relied upon by Patent Owner and Dr. Anna to show
commonly known inlet and outlet wells includes Figure 1A of Exhibit 2033,
which is reproduced below:

Ex. 2033, Fig. 1A. The above figure shows a PDMS substrate layer with
two microchannels (light gray) formed along the bottom of the PDMS layer
and a cylindrical hole at each end (inlet and outlet) of the microchannel. Id.;
Ex. 1071 ¶ 28. The parties’ experts agree that the above figure shows inlet
and outlet wells like those formed by Ismagilov 091’s hole-punch technique

13 Ex. 2033, S. Sia & G. Whitesides, Microfluidic Devices Fabricated in
Poly(Dimethylsiloxane) for Biological Studies, 24 Electrophoresis 3563
(2003).
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for making outlet wells or reservoirs. Ex. 1071 ¶¶ 27, 28; Ex. 2016 ¶¶ 35,
68, 137. Figure 1A of Exhibit 2033 and Dr. Anna’s testimony that it was
common to create inlets and outlets by punching a hole through the PDMS at
the ends of the channels (Ex. 2016 ¶ 68) buttress Dr. Fair’s opinion that a
POSA “would understand the disclosure of an outlet ‘well’ [in
Ismagilov 091] to refer to an open-topped, bucket-like structure from which
the accumulated droplets could be extracted, e.g., by using a micropipette.”
Ex. 1008 ¶ 161; see also Ex. 1071 ¶ 35 (a POSA would understand “well”
and “reservoir” in Ismagilov 091 “to be vertical, bucket-shaped storage
areas”).
The parties’ experts also agree that a POSA would know that the
smallest micropipette tip is 1 mm in diameter. Ex. 1071 ¶ 30; Ex. 2016
¶ 132; Ex. 2017, 159:13–16. In view of Ismagilov 091’s disclosure of an
“outlet . . . adapted for . . . [c]ollection . . . using micropipettes” (Ex. 1004,
17:27–30), we credit Dr. Fair’s testimony that a POSA would understand
Ismagilov 091 as disclosing a collection well having a diameter greater than
the 1 mm diameter micropipette tip, for example, a 2 mm or 4 mm diameter
hole cut in the PDMS using a cork borer. Ex. 1071 ¶¶ 30, 31, 33, 37. Patent
Owner does not dispute that a hole of this diameter cut in a substrate of the
thickness disclosed in Ismagilov 091 (“about 1 micrometer to about 1 cm”
(Ex. 1004, 8:5–6)) satisfies its constructions for “separation chamber” and
“droplet receiving outlet.” See generally PO Resp. 29–38 (addressing claim
element 1.3); PO Sur-reply 4–13 (same). In fact, Patent Owner admits that
these dimensions “match what Patent Owner accuses of infringement.” PO
Sur-reply 12–13.
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e) Element 1.4
Claim element 1.4 recites: “wherein the separation chamber is upright
to the microchannel and out of the horizontal plane.” Ex. 1001, 88:12–14
(hereinafter, the “upright” limitation).
Petitioner contends that Ismagilov 091 discloses the “upright”
limitation “[b]ecause Ismagilov describes forming the substrate and closing
the channels with a glass coverslip” so that “the well or reservoir would
extend up and out of the plane of the microchannels.” Pet. 40–41 (citing
Ex. 1004, 16:37–41, 30:2–9). Petitioner contends that “[t]he extension of
the well or reservoir out of the horizontal plane of the microchannels is
confirmed because the volume of an outlet well or reservoir in Ismagilov
must permit collecting multiple droplets and must be large enough that the
fluid can be collected by micropipette.” Pet. 41 (citing Ex. 1004, 17:27–30).
Patent Owner argues that Ismagilov 091 does not disclose the
“upright” limitation. PO Resp. 38–41.
We find that Petitioner shows persuasively that Ismagilov 091
discloses an outlet well or reservoir (corresponding to the claimed
“separation chamber”) that meets the “upright” limitation. Pet. 40–41. The
parties agree that Ismagilov 091 discloses making wells or reservoirs at the
ends of the channels by cutting a hole in the PDMS substrate using, for
example, a cork borer. Ex. 1004, 16:35–36; PO Resp. 9, 36; Pet. Reply 7–8.
Ismagilov 091 discloses that, after these holes are cut, the PDMS substrate
containing molded channels is placed onto a microscope cover slip, which
forms the base/floor or top of the channels. Ex. 1004, 16:38–41, 16:60–63,
30:5–8. Petitioner shows persuasively that this method results in a well or
reservoir that is upright to the microchannel and out of the horizontal plane
of the microchannels. Pet. 40–41; Ex. 1008 ¶ 160.
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Our finding is confirmed by Figure 1A of Exhibit 2033 (reproduced
above), which the parties’ experts agree shows inlet and outlet wells like
those formed by Ismagilov 091’s hole-cutting process. Ex. 1071 ¶¶ 27, 28;
Ex. 2016 ¶¶ 35, 68, 137. As shown in the figure, the cylindrical holes
(wells) are upright to the microchannels and out of the horizontal plane of
the microchannels. Ex. 2033, Fig. 1A. Petitioner also shows persuasively
that Ismagilov 091’s wells or reservoirs need to extend out of the horizontal
plane of the microchannels so as to have sufficient volume and depth to
permit collection of their contents by micropipette. Pet. 41 (citing Ex. 1004,
17:27–30; Ex. 1008 ¶ 161).
Patent Owner argues that a POSA “would just as easily understand
this disclosure [in Ismagilov 091] could be describing a ‘sample tube,’
‘centrifuge tube,’ or ‘micropipette’ inserted into the end of the outlet port in
the horizontal plane, without the volume requirements petitioner asserts
must be present.” PO Resp. 39 (quoting Ex. 1004, 17:27–30 and citing
Ex. 1004, 39:57–40:2, Fig. 22D; Ex. 2016 ¶¶ 140, 141).
We determine that, to the extent Patent Owner’s argument pertains to
collection using a micropipette, it is refuted by Dr. Anna’s testimony that “in
order for such a collection to be possible in the first place[,] a micropipette
tip would need to fit inside the punch holes as Ismagilov explains they
would be created.” Ex. 2016 ¶ 131 (emphasis added). There is no dispute
that the “punch holes” referenced by Dr. Anna (id.) and described by
Ismagilov 091 as “[h]oles . . . cut into the PDMS” are perpendicular to the
horizontal plane of the microchannels. Ex. 1004, 16:35–36; Ex. 1071
¶¶ 27, 28, 37; Ex. 2016 ¶¶ 35, 68, 137; Ex. 2033, Fig. 1A.
The evidence of record does not support Patent Owner’s argument
that “[c]ollection . . . using micropipettes,” as disclosed by Ismagilov 091
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(Ex. 1004, 17:29–30), refers to inserting a micropipette into the end of the
outlet port in the horizontal plane. PO Resp. 39, 41. Petitioner’s undisputed
evidence shows that a micropipette must be operated vertically, not
horizontally, in order to collect fluids. Ex. 1040, 6 (“Tip angle is also
important. Hold the pipette vertically, or within 20 degrees of vertical.”);
id. at 7 (“Never invert or lay the pipette down if liquid is in the tip.”). The
portions of Ismagilov 091 cited by Patent Owner (PO Resp. 39) do not relate
to collection using a micropipette. Ex. 1004, 39:57–40:2, Fig. 22D (showing
a device with “multiple outlets that can be closed or opened”). Although
Patent Owner relies on Dr. Fair’s testimony about devices he built (PO
Resp. 40 (quoting Ex. 2017, 69:2–18)), that testimony is not related to
Ismagilov 091 or the disclosures Petitioner relies upon to show the “upright”
limitation of claim 1.
f) Element 1.5
Claim element 1.5 recites: “wherein the droplet formation module
and the separation chamber are in fluid communication with each other via
the microchannel.” Ex. 1001, 88:15–17.
Petitioner contends that Ismagilov 091 discloses that the separation
chamber (Ismagilov 091’s outlet well) and droplet formation module are in
fluid communication via a microchannel. Pet. 43 (citing Ex. 1004, 3:15–20,
14:21–35, 21:48–54). Patent Owner does not dispute Petitioner’s contention
about claim element 1.5 separate from its other arguments about a
“separation channel.” PO Resp. 41.
We find that Ismagilov 091 discloses a plug-forming region
(corresponding to the claimed “droplet formation module”) in fluid
communication with an outlet well or reservoir (corresponding to the
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claimed “separation chamber”) via a first channel (corresponding to the
claimed “microchannel”). Our finding is supported by the following
disclosures in Ismagilov 091: “a device is provided that includes . . . a first
channel comprising an inlet separated from an outlet” (Ex. 1004, 14:20–22);
“[e]ach of the outlet and inlet ports may also communicate with a well or
reservoir” (id. at 14:37–38); “plugs are formed by introducing the plug-fluid,
at the plug-forming region, into the flow of carrier-fluid passing through the
first channel” (id. at 21:48–50); and “[t]he force and direction of flow can be
controlled . . . [to] permit[] the movement of the plugs into one or more
desired branch channels or outlet ports” (id. at 21:50–54).
g) Element 1.6
Claim element 1.6 recites: “wherein the separation chamber has a
wider cross-section than the microchannel cross-section to accumulate a
plurality of droplets comprising the sample.” Ex. 1001, 88:18–21
(hereinafter the “width” limitation).
Petitioner contends that Ismagilov 091’s “wells or reservoirs ‘collect’
plugs.” Pet. 44 (citing 8:41–44, 9:5–8, 14:36–38, 17:27–30). Petitioner
asserts that, in Ismagilov 091, the droplets are not being accumulated single
file in a structure with the cross-section of a channel, but instead are being
pooled in a collection vessel that is deep and wide enough to permit
removing the droplets with a micropipette. Pet. 44–45 (citing Ex. 1008
¶ 170).
Patent Owner does not dispute Petitioner’s contention about the
“width” limitation separate from its other arguments about a “separation
chamber.” See PO Resp. 41–43 (addressing claim elements 1.6 and 1.7
together).
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We credit Dr. Fair’s testimony that Ismagilov 091 discloses pooling
droplets in a vessel deep and wide enough to accommodate a micropipette.
Ex. 1008 ¶ 170. As discussed above, we also credit Dr. Fair’s testimony that
a POSA would understand Ismagilov 091 as disclosing an outlet well with a
diameter greater than the diameter of the smallest micropipette, i.e., a
diameter greater than 1 mm. Ex. 1071 ¶¶ 30, 31, 33, 37. There is no dispute
that such an outlet well has a wider cross-section than the microchannel
cross-section. Ismagilov 091 discloses a channel diameters of 30 to 60 µm.
Ex. 1004, 15:34–40.
h) Element 1.7
Claim element 1.7 recites that the separation chamber “is of a volume
sufficient to separate the plurality of droplets comprising the sample from
the immiscible fluid within the separation chamber.” Ex. 1001, 88:21–23.
Petitioner contends that Ismagilov 091 discloses an outlet well or
reservoir that “collects both a plurality of droplets and a volume of
immiscible fluid.” Pet. 45 (citing Ex. 1004, Figs. 2–10). According to
Petitioner, Ismagilov 091 discloses aqueous droplets in fluorinated oil, and
because there is a density difference between those two liquids, they will
separate when the droplets and immiscible fluid are pooled in the outlet well
or reservoir. Pet. 46.
Patent Owner relies on the same arguments for claim element 1.7 as it
presented for the other separation chamber limitations of claim 1. PO
Resp. 41. In addition, Patent Owner argues that, “[d]epending on the density
of the particular oil that is selected, the droplets will not necessarily
separate,” for example, “the drops will not necessarily separate if the
selected oil has substantially the same density as water.” Id. at 42–43.
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For the reasons discussed above in connection with claim element 1.3,
we find that Ismagilov 091 discloses an outlet well or reservoir that collects
both a plurality of droplets and a volume of immiscible fluid. Ex. 1004,
9:5–8, 14:37–38, 16:35–36, 21:48–54; see also id. at Fig. 3, 4:6–10
(depicting and describing “a stream of plugs from an aqueous plug-fluid and
an oil (carrier-fluid) in curved channels”). Petitioner is correct that
Ismagilov 091 discloses aqueous droplets with fluorinated oil as the
immiscible fluid. Pet. 46; Ex. 1004, 9:38–44, 20:37–38, 20:64–67. Patent
Owner does not challenge Petitioner’s assertion that, because of a difference
in density, aqueous droplets will necessarily float in fluorinated oil. Pet. 10–
11; Ex. 1008 ¶ 57; PO Resp. 42; Ex. 2016 ¶ 148. Claim element 1.7 requires
a “volume sufficient to separate,” not actual separation. Nevertheless,
because Ismagilov 091 expressly discloses an outlet well or reservoir that
collects aqueous droplets and fluorinated oil (see, e.g., Ex. 1004, 20:64–67),
Petitioner has established that Ismagilov 091 inherently discloses separation
of the droplets from the immiscible fluid. Pet. 46; Ex. 1008 ¶¶ 57, 174.
i) Conclusion for Independent Claim 1
Accordingly, after considering both parties’ arguments and evidence,
we are persuaded that Ismagilov 091 discloses all limitations of claim 1. We
conclude that Petitioner has shown by a preponderance of the evidence that
claim 1 is anticipated by Ismagilov 091.
3. Dependent Claims
a) Claim 2
Claim 2 depends from claim 1 and recites: “wherein an aqueous fluid
from the sample inlet is segmented with an immiscible fluid from the
immiscible fluid inlet at the junction.” Ex. 1001, 88:24–26.
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Relying on its explanation for claim element 1.2, Petitioner contends
that Ismagilov 091 discloses aqueous droplets and segmenting by immiscible
fluid at the junction. Pet. 47.
Patent Owner presents no arguments for dependent claim 2 separate
from its arguments for independent claim 1. See PO Resp. 43.
We find that Ismagilov 091 discloses the limitation of claim 2 for the
same reasons as discussed above for claim element 1.2.
b) Claim 4
Claim 4 depends from claim 1 and recites: “wherein the at least one
droplet receiving outlet is located on the upper portion of the separation
chamber.” Ex. 1001, 88:30–32.
Relying on its explanation for claim 1, Petitioner contends that
Ismagilov 091 describes the droplet receiving outlet on the upper portion of
the separation chamber. Pet. 47.
Patent Owner presents no arguments for dependent claim 4 separate
from its arguments for independent claim 1. See PO Resp. 43.
We find that Ismagilov 091 discloses the limitation of claim 4 for the
same reasons as discussed above for claim element 1.3. More specifically,
we find that Ismagilov 091 discloses an open-topped outlet well or reservoir
from which droplets can be extracted using a micropipette, where the open
top of the well or reservoir corresponds to the “droplet receiving outlet” and
is located on the upper portion of the well or reservoir that corresponds to
the “separation chamber.” Ex. 1004, 9:5–8, 14:37–38, 16:35–36, 17:18–30;
Ex. 1008 ¶¶ 130, 131, 134, 161.
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c) Claim 10
Claim 10 depends from claim 1 and recites: “wherein the droplet
receiving outlet receives substantially one or more droplets.” Ex. 1001,
88:46–47.
Relying on its explanation for claim 1, Petitioner contends that
Ismagilov 091 discloses a droplet receiving outlet that receives substantially
one or more droplets. Pet. 48.
Patent Owner presents no arguments for dependent claim 10 separate
from its arguments for independent claim 1. See PO Resp. 43.
We determine that Ismagilov 091 discloses the limitation of claim 10
for the same reasons as discussed above for claim element 1.3. More
specifically, we find that Ismagilov 091 discloses an open-topped outlet well
or reservoir from which substantially one or more droplets can be extracted
using a micropipette, where the open top of the well or reservoir corresponds
to the claimed “droplet receiving outlet.” Ex. 1004, 9:5–8, 14:37–38,
16:35–36, 17:18–30; Ex. 1008 ¶¶ 130, 131, 134, 161.
d) Claim 11
Claim 11 depends from claim 1 and recites: “further comprising a
reagent inlet, wherein the reagent inlet is in fluid communication with the
junction or the microchannel.” Ex. 1001, 88:48–50.
Petitioner contends that Ismagilov 091 discloses a reagent inlet in
communication with the junction at which droplets are formed. Pet. 49–50
(citing Ex. 1004, 10:60–11:7, 18:49–58, 19:5–18, Figs. 4, 5). Petitioner
contends that Ismagilov 091 also discloses a reagent inlet in communication
with the microchannel in which the droplets merge. Pet. 51 (citing Ex. 1004,
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3:14–33, 6:48–54, 15:10–23, 18:16–19, 27:37–39, 27:53–58, 49:18–19,
66:32–42, Figs. 37, 38).
Patent Owner presents no arguments for dependent claim 11 separate
from its arguments for independent claim 1. See PO Resp. 43.
Claim 11 recites a reagent inlet in fluid communication with either the
junction or the microchannel. We find that Ismagilov 091 discloses a
reagent inlet in fluid communication with the junction at which droplets are
formed. For example, Figure 4 of Ismagilov 091 shows inlet ports 401–405
in fluid communication with a junction with an oil channel, where oil is
introduced into carrier fluid inlet port 400, multiple aqueous plug-fluid
reagents or solvents are introduced into inlet ports 401–405, and droplets
(plugs) are formed at the junction. Ex. 1004, 18:49–58, Fig. 4.
Because we find that Ismagilov 091 discloses a reagent inlet in fluid
communication with the junction, we do not need to consider whether
Ismagilov 091 discloses a reagent inlet in fluid communication with the
microchannel.
e) Claim 12
Claim 12 depends from claim 11 and recites: “wherein the reagent
inlet introduces one or more amplification reagents to the junction or the
microchannel.” Ex. 1001, 88:51–53.
Petitioner contends that Ismagilov 091 discloses devices and methods
for conducting “autocatalytic reactions, and describes ‘polymerase-chain
reaction (PCR)’ as such an autocatalytic reaction that ‘is a very effective
amplification method that has been widely used in the biological sciences.’”
Pet. 53 (citing Ex. 1004, 45:57–46:5, 47:22–34). Petitioner contends that
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“Ismagilov teaches that amplification reagents, including those for PCR,
could be introduced through the reagent inlets.” Pet. 54.
Patent Owner presents no arguments for dependent claim 12 separate
from its arguments for independent claim 1. See PO Resp. 44.
We find that Ismagilov 091 discloses a reagent inlet that introduces
one or more amplification reagents to the junction. More specifically,
Ismagilov 091’s Examples 7 and 9 and Figures 37 and 38 illustrate
experiments in which chemical amplification reagents are introduced into
the reagent inlets of a microfluidic device. Ex. 1004, 66:21–66:56, 67:40–
68:55, Figs. 37, 38. In Example 7 and Figure 37, for example, a three-
channel inlet introduces a first set of reagents through channels 3701–3703,
which are in fluid communication with oil channel 3713 at a first plug-
forming junction, and a five-channel inlet introduces a second set of reagents
through channels 3705–3709, which are in fluid communication with oil
channel 3714 at a second plug-forming junction. Id. at 66:32–43, Fig. 37.
When plugs 3704 containing the first set of reagents merge with plugs 3710
containing the second set of reagents at contact region 3712, an autocatalytic
amplification reaction is triggered. Id. at 66:49–56.
f) Claim 13
Claim 13 depends from claim 12 and recites: “wherein the one or
more amplification reagents are for a polymerase chain reaction.” Ex. 1001,
88:54–55.
Petitioner contends that Ismagilov 091 discloses that autocatalytic
reactions such as PCR could be carried out using the disclosed microfluidic
devices, which would involve introducing amplification reagents into the
reagent inlets. Pet. 54.
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Patent Owner presents no arguments for dependent claim 13 separate
from its arguments for independent claim 1. See PO Resp. 44.
We find that a POSA reading Ismagilov 061 would “at once envisage”
introducing amplification reagents for PCR into the reagent inlets of the
microfluidic devices. Kennametal, Inc. v. Ingersoll Cutting Tool Co., 780
F.3d 1376, 1381 (Fed. Cir. 2015) (A reference can anticipate a claim, even if
it “‘d[oes] not expressly spell out’ all the limitations arranged or combined
as in the claim, if a person of skill in the art, reading the reference, would ‘at
once envisage’ the claimed arrangement or combination.” (quoting In re
Petering, 301 F.2d 676, 681 (CCPA 1962)). Although Ismagilov 091 does
not disclose a specific example illustrating the introduction of amplification
reagents for PCR into the reagent inlet of a microfluidic device, disclosure of
such a specific example is not required for anticipation. Kennametal,
780 F.3d at 1383 (“Though it is true that there is no evidence in [prior art
reference] of ‘actual performance’ of combining [claimed components], this
is not required” for anticipation.). Ismagilov 091 discloses PCR as one of a
limited number of specific examples of autocatalytic amplification reactions
that can be carried out using microfluidic devices. Ex. 1004, 11:32–40,
46:2–5 (disclosing PCR as an “example of an autocatalytic reaction . . .
which is a very effective amplification method that has been widely used in
the biological sciences”); id. at 46:16–34 (disclosing a reaction between
NaClO2 and NaS2O3 “used for a highly sensitive amplification process”); id.
at 46:46–47:9, 66:60–67:38 (disclosing an autocatalytic amplification
involving the reaction of Co(III)-5-Br-PAPS) with KHSO4). Furthermore,
Ismagilov 091 discloses Examples 7 and 9, which illustrate two of these
amplification reactions (id. at 66:21–66:56, 67:40–68:55) and describe
introducing amplification reagents into the reagent inlets of a microfluidic
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device (id. at 66:32–37, Fig. 37, 67:47–51, Fig. 38). In our view, a POSA
reading Ismagilov 091 would “at once envisage” experiments in which
amplification reagents for PCR are introduced into the reagent inlets, as
recited in claim 13, because Ismagilov 091 discloses PCR as one of a limited
number of specific amplification reactions and also discloses examples in
which amplification reagents are introduced into the reagent inlets of a
microfluidic device. Kennametal, 780 F.3d at 1381.
g) Claim 19
Claim 19 depends from claim 1 and recites: “further comprising a
sorting module to direct the flow of droplets, wherein the sorting module is
located between the droplet formation module and the separation chamber.”
Ex. 1001, 89:1–4.
Petitioner contends that Ismagilov 091 discloses a sorting module that
meets the limitations of claim 19. Pet. 54–55 (citing Ex. 1004, 9:5–8,
14:36–38, 15:41–45, 15:46–52, 21:55–59, 31:20–33:18).
Patent Owner presents no arguments for dependent claim 19 separate
from its arguments for independent claim 1. See PO Resp. 44.
We find that Ismagilov 091 discloses a sorting module to direct the
flow of droplets. For example, Ismagilov 091 discloses a “detection region”
defined as “a location in a substrate or channel wherein a chemical is
identified, measured, or sorted based on a predetermined property or
characteristic.” Ex. 1004, 7:61–64 (emphasis added). Ismagilov 091
discloses that the “detection region” is located “downstream of the plug-
forming region” and “upstream of the discrimination region or branch
point.” Id. at 15:46–52. Ismagilov 091 discloses that plugs are “sorted
dynamically in a flow stream of microscopic dimensions” and that various
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characteristics can be used to sort plugs. Id. at 21:55–59, 31:50–53.
Ismagilov 091 discloses that a “variety of channels . . . can be fabricated . . .
as the detection and discrimination or sorting points” and that these channels
lead to an outlet that may include a well or reservoir and allow for collection
of plugs using micropipettes. Id. at 14:37–38, 17:10–30. As discussed
above, Ismagilov 091’s outlet well or reservoir is a “separation chamber.”
Accordingly, we find that Ismagilov 091 discloses that the sorting module is
located between the droplet formation module and the separation chamber.
h) Claim 20
Claim 20 depends from claim 19 and recites: “wherein the sorting
module comprises an apparatus to generate an electric force.” Ex. 1001,
89:5–6.
Petitioner contends that Ismagilov 091 discloses that the sorting
module includes an apparatus—electrodes—to generate electrical force,
which can move the droplets. Pet. 55–56 (citing Ex. 1004, 28:35, 29:31–
39).
Patent Owner presents no arguments for dependent claim 20 separate
from its arguments for independent claim 1. See PO Resp. 44.
We find that Ismagilov 091 discloses that the sorting module
comprises an apparatus to generate an electric force. Our finding is
supported by Ismagilov 091, which includes a section titled “Splitting and/or
Sorting Plugs,” which discloses that “electrodes can be fabricated onto a
substrate” to control the movement of plugs using dielectrophoresis.
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i) Conclusion for Dependent Claims
We conclude that Petitioner has shown by a preponderance of the
evidence that dependent claims 2, 4, 10–13, 19, and 20 are anticipated by
Ismagilov 091.
E. Petitioner’s Ground 2: Ismagilov 091 and Quake
Petitioner contends that claims 1, 2, 4, 7, 9–13, 19, and 20 are
unpatentable as obvious over Ismagilov 091 and Quake. Pet. 31–56. We
first provide an overview of Quake and then turn to the parties’ contentions
and our analysis.
1. Quake (Ex. 1006)
Quake is a U.S. Patent Publication titled “Microfabricated Crossflow
Devices and Methods.” Ex. 1006, codes (10), (54). Petitioner asserts that
Quake is prior art to the ’837 Patent under 35 U.S.C. § 102(a)(2) and pre-
AIA 35 § 102(e) as of its September 14, 2001 filing date and under
§ 102(a)(1) and pre-AIA § 102(a) and (b) as of its May 16, 2002 publication
date. Pet. 14–15. Patent Owner does not contest the prior art status of
Quake. We find that Quake is prior art to the ’837 Patent, regardless of
whether the AIA applies to the patent.
Quake discloses “microfluidic devices and methods,” including
devices “designed to compartmentalize small droplets of aqueous solution
within microfluidic channels filled with oil.” Ex. 1006 ¶ 3. More
specifically, Quake discloses:
The devices and methods of the invention comprise a main
channel, through which a pressurized stream of oil is passed, and
at least one sample inlet channel, through which a pressurized
stream of aqueous solution is passed. A junction or “droplet
extrusion region” joins the sample inlet channel to the main
channel such that the aqueous solution can be introduced to the
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main channel, e.g., at an angle that is perpendicular to the stream
of oil. By adjusting the pressure of the oil and/or the aqueous
solution, a pressure difference can be established between the
two channels such that the stream of aqueous solution is sheared
off at a regular frequency as it enters the oil stream, thereby
forming droplets.
Id.; see also id. ¶ 84 (describing droplet extrusion region).
Figure 6 of Quake is reproduced below:

Quake Figure 6 is a photograph showing a microfabricated device (“chip”)
with an inlet channel and reservoir (labeled “well” at lower right side of
Figure 6), a detection region (labeled “main channel” in Figure 6), a branch
point (labeled “junction” in Figure 6), and two outlet channels and reservoirs
(each labeled “well” at the left side and upper right side of Figure 6).
Ex. 1006 ¶¶ 29, 196.
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Quake discloses the process by which the chip of Figure 6 was
molded from a silicone elastomer. Ex. 1006 ¶ 196. According to Quake, a
negative master mold was made from a silicon wafer by standard
photolithography and micromachining techniques. Id. ¶¶ 195, 196, Fig. 7
(showing etching process). Elastomer components were mixed together and
poured onto the etched silicon wafer. Id. ¶ 196. After curing, the elastomer
was peeled from the wafer. Id. The chip was treated to make the elastomer
surface hydrophilic. Id. As shown in Figure 6, an inlet well and two
collection wells were incorporated into the elastomer chip on three sides of a
“T” arrangement of channels. Id. ¶ 197. The elastomer chip was then
adhered to a glass coverslip. Id. ¶¶ 196, 197.
According to Quake, the device shown in Figure 6 has the following
dimensions: The channels “are 100 µm wide at the wells, narrowing to
3 µm at the sorting junction (discrimination region). The channel depth is
4 µm, and the wells are 2 mm in diameter.” Ex. 1006 ¶ 196. Quake
discloses that the microfabricated device of Figure 6 can be used in sorting
cells or biological materials. Id. ¶ 193.
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Figure 8 of Quake is reproduced below.

Quake Figure 8 shows a schematic representation of an apparatus for sorting
cells or beads using the microfabricated device of Figure 6. Ex. 1006 ¶¶ 31,
197. As shown in Figure 8, the microfabricated cell-sorting device (silicone
elastomer chip) was mounted on an inverted microscope for optical
detection of fluorescence emission of laser-stimulated cells. Id. Electrodes
were inserted into each of the three wells (the inlet well and two collection
wells) to direct the flow of cells. Id. ¶¶ 197, 198, Fig. 8. Responsive to
optical detection, voltages on the electrodes were used to direct the cells to
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one or the other of the collection wells on each side of the “T” junction. Id.
¶¶ 31, 198.
2. Motivation to Combine
Petitioner contends that, to the extent a POSA would not have known
the structure of features such as Ismagilov 091’s wells, a POSA would have
been motivated to look to art that further describes the structure of wells,
namely Quake. Pet. 25. According to Petitioner, “[i]f a POSA with
Ismagilov would want additional information regarding microfluidic
structures, the POSA would have looked to the work of a leader in
developing early microfluidic devices: Quake.” Pet. 27–28 (citing Ex. 1008
¶ 107). Petitioner contends that a POSA would have combined the
microfluidic configurations, organizations, uses, substrate compositions, and
fluids disclosed in Ismagilov 091—including placement of wells, reservoirs,
or chambers—with the structures and dimensions for wells or reservoirs,
their inlets and outlets, and channels disclosed in Quake. Pet. 39–40 (citing
Ex. 1004, 16:2–47).
Patent Owner argues that a POSA would not have had a motivation to
combine Ismagilov 091 and Quake because the references have “different
purposes.” PO Resp. 45–48. Patent Owner asserts that Ismagilov 091 is
“focused on microfabricated substrates for forming droplets,” and the
examples of Quake relied upon by Petitioner are “focused on cell sorting and
did not use droplets.” Id. at 45. In addition, Patent Owner argues that
Petitioner “fails to explain how a POSA would go about combining the
disparate elements of the references, or what modifications a POSA would
necessarily have made in order to combine the disparate elements.” PO
Resp. 47.
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We are persuaded by Petitioner’s argument that a POSA would have
consulted Quake to obtain additional information about the structure and
dimensions of the wells or reservoirs, inlets and outlets, and channels that
are disclosed in somewhat less detail in Ismagilov 091. Pet. 25, 39–40.
Petitioner is not combining “disparate elements,” as argued by Patent
Owner. PO Resp. 47. Instead, Petitioner is relying on Quake to provide
explicit disclosure of the structure and dimensions of features, particularly
outlet wells, that are already expressly described by Ismagilov 091. As
support for a motivation to combine, Petitioner cites Ismagilov 091’s
description of fabrication of channels, substrates, and devices. Pet. 40
(citing Ex. 1004, 16:2–47). That description is very similar to Quake’s
description of fabrication of a microfabricated device that Petitioner relies
upon to provide additional details regarding the dimensions and
configuration of the wells or reservoirs, their inlets and outlets, and
channels. Pet. 38–42, 45–46 (citing Ex. 1006 ¶¶ 196–200, Figs. 6–8).
In this instance, we view the similarities between Ismagilov 091 and
Quake as strong support for combining the references’ teachings relied upon
by Petitioner. More specifically, Petitioner relies on Quake’s disclosure of
the manufacture and operation of a microfabricated device. Pet. 38–42, 45–
46; Ex. 1006 ¶¶ 192–200. Quake’s procedure for microfabrication is very
similar to the procedure disclosed by Ismagilov 091. Compare Ex. 1004,
16:1–47 (“Fabrication of Channels, Substrates, and Devices”), with Ex. 1006
¶¶ 194–197 (“Preparation of the microfabricated device”). For example,
both references disclose that channels are molded from a silicone elastomer
using an etched silicon wafer with a negative image of the channels as a
mold. Ex. 1004, 16:23–25; Ex. 1006 ¶ 196. Ismagilov 091 discloses that
“[h]oles may be cut into the PDMS using, for example, a tool such as a cork
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borer or a syringe needle.” Ex. 1004, 16:35–36. According to Patent Owner
and Dr. Anna, a POSA would have understood that these “[h]oles”
correspond to the “wells or reservoirs” that Ismagilov 091 discloses at the
inlet and outlet ports. Id. at 14:37–38; PO Resp. 2, 9, 36; Ex. 2016 ¶¶ 35,
68, 137. Similar to Ismagilov 091’s description of forming inlet and outlet
wells, Quake describes an “inlet well and two collection wells . . .
incorporated into the elastomer chip on three sides of the ‘T’ forming three
channels.” Compare Ex. 1004, 16:35–36 (quoted above), with Ex. 1006
¶ 197 (quoted here). Quake’s inlet and collection wells are shown in
Figures 6 and 8. Ex. 1006, Figs. 6, 8.
Patent Owner argues that Ismagilov 091 and Quake would not have
been combined because they “relate to two completely different structures
and assemblies with two completely different intended uses,” namely cell-
sorting in Quake and droplet formation in Ismagilov 091. PO Resp. 45–47.
We disagree. The Quake disclosure relied upon by Petitioner is part of
Example 7, which demonstrates the manufacture and operation of a cell-
sorting device that “can function as a stand-alone device or as a component
of an integrated microanalytical chip.” Ex. 1006 ¶ 193. More broadly than
the specific examples, Quake discloses a “microfluidic device for analyzing
and/or sorting biological materials,” where the device includes a “droplet
extrusion region.” Id. at code (57), ¶¶ 3, 4, 15. Accordingly, although
Example 7 demonstrates a cell-sorting, Quake plainly contemplates that the
cell-sorting device can be integrated into a chip that includes a droplet
extrusion region.
Accordingly, we find that Petitioner has shown that a POSA would
have had a reason to combine the microfluidic configurations, organizations,
uses, substrate compositions, and fluids disclosed in Ismagilov 091 with the
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structures and dimensions for wells or reservoirs, their inlets and outlets, and
channels disclosed in Quake.
3. Claim 1
Petitioner contends that claim elements 1.0, 1.1, 1.2, and 1.5 are
disclosed by Ismagilov 091. Pet. 31–35, 43.
Regarding claim element 1.3, Petitioner contends that Quake
describes and shows the wells or reservoirs as large, open structures with
inlets from channels and electrodes inserted into the open wells. Pet. 38–39
(citing Ex. 1006 ¶¶ 198–200, Figs. 6, 8).
Regarding claim element 1.4, Petitioner contends that Quake confirms
that the wells or reservoirs extend upright and out of the plane of the
microchannels. Pet. 42. Petitioner relies on Quake’s disclosed well and
channel dimensions, a calculation of the height of Quake’s wells, and
Quake’s description of how the microfluidic chip is fabricated and combined
with electrodes and a microscope. Id. (citing Ex. 1006 ¶¶ 196–198, 200,
Figs. 6–8).
Regarding claim element 1.6, Petitioner cites Quake’s well and
channel dimensions to show that, in the proposed combination of
Ismagilov 091 and Quake, the wells have a wider cross-section than the
channels and have a volume that can accumulate a plurality of droplets.
Pet. 45 (citing Ex. 1006 ¶ 196).
Regarding claim element 1.7, Petitioner contends that, “given the
large size of the wells specified by Quake, . . . the volume of the well or
reservoir will be sufficient to separate droplets under Bio-Rad’s contentions
because it is sufficient to accumulate a plurality of droplets in a volume of
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immiscible fluid where the droplets have a different density from the
immiscible fluid.” Pet. 46–47.
Patent Owner contends that Quake does not disclose a “separation
chamber” and the related limitations of claim 1. PO Resp. 48–49.
For claim elements 1.0, 1.1, 1.2, and 1.5, we find that the limitations
are disclosed by Ismagilov 091 for the same reasons as discussed in section
II.D.2 above. Petitioner’s combination of Ismagilov 091 with Quake does
not change our analysis for these claim elements.
Regarding claim element 1.3, we find that Ismagilov 091 teaches an
outlet well that is downstream from the droplet formation module. Ex. 1004,
9:5–8, 14:20–22, 14:36–40, 21:48–54. It is undisputed that Ismagilov 091’s
outlet wells are made by punching a hole in the PDMS substrate. PO
Resp. 2, 9, 36; Pet. Reply 7–8; Ex. 1004, 16:35–36; Ex. 2016 ¶¶ 35, 137;
Ex. 2033, Fig. 1A. In view of this undisputed evidence, there does not
appear to be any dispute about whether Ismagilov 091’s outlet wells are
open-topped. Nevertheless, we agree with Petitioner that Quake confirms
that Ismagilov 091’s outlet wells are open-topped. Pet. 38. More
particularly, Quake discloses collection wells made in the same way as
Ismagilov 091’s outlet wells. Compare Ex. 1006 ¶ 197 (“The inlet well and
two collection wells were incorporated into the elastomer chip on three sides
of the ‘T’ forming three channels (FIGS. 6 and 7).”), with Ex. 1004, 16:35–
36 (“Holes may be cut into the PDMS using, for example, a tool such as a
cork borer or a syringe needle.”). Quake’s inlet well and two collection
wells are shown in Figure 6 and again in Figure 8, which depicts three open-
topped wells with electrodes inserted into the wells. Ex. 1006, Fig. 8, ¶ 198
(“Three platinum electrodes were each inserted into separate wells.”).
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We are persuaded that our claim constructions for “separation
chamber” and “droplet receiving outlet” are met by an outlet well as taught
by Ismagilov 091 (Ex. 1004, 9:5–8, 14:36–40), having a 2 mm diameter as
taught by Quake (Ex. 1006 ¶ 196), a depth within the range taught by both
references (Ex. 1004, 16:46 (substrate can be “about 1 micron to about 1 cm
in thickness”); Ex. 1006 ¶ 88 (same)), an inlet as described in Ismagilov 091
(Ex. 1004, 9:5–8, 14:36–40) and as shown in Quake Figure 6, and an open
top produced by punching a hole as described by Ismagilov 091 (Ex. 1004,
16:35–36) and depicted in Quake Figures 6 and 8 (Ex. 1006 ¶¶ 197, 198).
Pet. 40; Pet. Reply 21–22.
Regarding claim element 1.4, we agree with Petitioner that Quake
confirms that the outlet wells or reservoirs, as disclosed in Ismagilov 091,
have a significant dimension extending above the plane of the
microchannels. Pet. 41–42. Patent Owner does not dispute Dr. Fair’s
calculation of the height of a cylindrical well having the diameter and
capacity disclosed in Quake. Pet. 42; Ex. 1006 ¶¶ 196, 200; Ex. 1008 ¶ 164.
Regarding claim element 1.6, Petitioner shows persuasively that
Quake teaches a collection well having a wider cross-section (2 mm
diameter) than the microchannel cross-section (4 µm depth by 100 µm width
at the wells, narrowing to 3 µm at the sorting junction). Pet. 45; Ex. 1006
¶ 196, Fig. 6. Patent Owner does not dispute that the combination of
Ismagilov 091 and Quake teaches this limitation.
Regarding claim element 1.7, Petitioner shows persuasively that
Ismagilov 091 teaches an outlet well that collects droplets and immiscible
fluid and, with the well dimensions and capacity specified by Quake
(Ex. 1006 ¶¶ 196, 200), the volume of the outlet well will be sufficient to
accumulate a plurality of droplets and to allow the droplets to separate from
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the immiscible fluid based on their different densities. Pet. 42, 46–47;
Ex. 1008 ¶ 176.
Patent Owner argues that Quake does not teach “wells intended for
separation.” PO Resp. 49. According to Patent Owner, Quake’s “collection
wells” are used for “sorting experiments” in which cells (not droplets) are
directed by voltages. Id. Patent Owner argues there is no disclosure of
separating droplets and immiscible fluid in Quake’s wells. Id.
After considering Patent Owner’s arguments, we are persuaded that
Petitioner has established that the combination of Ismagilov 091 with Quake
teaches the claimed “separation chamber” and related limitations. Whether
Quake teaches “wells intended for separation” or “separating droplets and
immiscible fluid in these wells” (PO Resp. 49) is not the correct test. Patent
Owner’s construction for “separation chamber,” which we adopt here, does
not require actual separation. Moreover, even if separation were required,
Petitioner shows persuasively that, due to a difference in density, the
droplets will necessarily separate from the immiscible fluid when the
droplets accumulate in the outlet well. Pet. 10–11, 46–47; Ex. 1008 ¶¶ 57,
174, 176.
Accordingly, we are persuaded that the combination of Ismagilov 091
and Quake teaches all limitations of claim 1.
4. Dependent Claims
a) Claims 2, 4, 10–13, 19, and 20
Neither party presents an analysis of claims 2, 4, 10–13, 19, and 20
under Ground 2 separate from the analysis under Ground 1. Pet. 47–56; PO
Resp. 49–53. For the reasons discussed in section II.D.3 above, we find that
Ismagilov 091 discloses the limitations of claims 2, 4, 10–13, 19, and 20.
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Petitioner’s combination of Ismagilov 091 with Quake does not change our
analysis for these claims.
b) Claim 7
Claim 7 depends from claim 1 and recites: “wherein the droplet
receiving outlet is coupled to a vessel.” Ex. 1001, 88:40–41.
Petitioner asserts that, according to Patent Owner’s infringement
contentions, “coupled” is “[b]road enough to encompass transporting by
pipette between an alleged outlet/chamber and vessel.” Pet. 19 (citing
Ex. 1026, 21–22). Addressing claim 7, Petitioner contends “[i]t is
understood by a POSA or obvious that the droplets collected from a well by
pipette would be transferred to another vessel for downstream use” and that
“such vessels were well known,” quoting Ismagilov 091’s disclosure of a
“centrifuge tube.” Pet. 48 (citing Ex. 1004, 17:27–30). According to
Petitioner, removing the droplets by pipette and transporting them to another
vessel meets the claim under Patent Owner’s interpretation. Id. (citing
Ex. 1008 ¶ 186).
Patent Owner argues that “coupled” should be construed as “operably
linked.” PO Resp. 26 (citing Ex. 2032). As support for this construction,
Patent Owner argues that “[t]he ‘coupling’ between the droplet receiving
outlet and the vessel is to effectuate transfer of droplets from the separation
chamber to the vessel.” Id. (citing Ex. 1001, 4:17–36). Addressing claim 7,
Patent Owner argues that, “because neither Ismagilov nor Quake disclose a
separation chamber with one or more droplet receiving outlets, . . . there is
also no disclosure of a ‘droplet receiving outlet’ being ‘coupled,’ or
‘operably linked,’ to another vessel.” Id. at 50. Patent Owner additionally
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argues that Petitioner “fails to identify any disclosure of a ‘separate vessel’
in either Ismagilov or Quake.” Id. at 50–51.
We determine that we do not need to provide an explicit construction
for “coupled” in order to resolve the parties’ dispute about claim 7. Patent
Owner agrees that claim 7 requires no physical or mechanical connection
between the droplet receiving outlet and a vessel and that transfer of droplets
from the outlet to a vessel using a pipette may constitute “coupling.” PO
Resp. 26–27. For the reasons discussed above, we find that the combination
of Ismagilov 091 and Quake teaches an outlet well that accumulates droplets
and immiscible fluid and that Ismagilov 091 teaches collection of droplets
from the outlet well using a micropipette. Ex. 1004, 9:5–8, 14:37–38,
16:35–36, 17:27–30, 21:48–54; Ex. 1006 ¶¶ 196, 197, Fig. 6. Patent Owner
presents no effective rebuttal to Petitioner’s contention that a POSA would
have understood that a micropipette can be used to collect droplets from an
outlet well and transfer them to another vessel and that such use meets the
limitation of claim 7. We are persuaded by Petitioner’s contention. Pet. 48;
Ex. 1008 ¶ 186.
c) Claim 9
Claim 9 depends from claim 7 and recites: “wherein the vessel is a
PCR tube or a test tube.” Ex. 1001, 88:44–45.
Petitioner contends that it would have been obvious to place droplets
in a centrifuge tube or PCR tube after the droplets have been transferred
from the well by a pipette. Pet. 48 (citing Ex. 1008 ¶¶ 191, 192).
Patent Owner presents no arguments for dependent claim 9 separate
from its arguments for independent claim 1. See PO Resp. 51.
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We determine that Petitioner has established it would have been
obvious to select a PCR tube or a test tube as the vessel for receiving the
transfer of droplets collected by micropipette from an outlet well. Pet. 48;
Ex. 1008 ¶ 192. The evidence shows that such vessels were known in the
art. Ex. 1004, 17:27–29 (disclosing the use of a “sample tube” such as a
“centrifuge tube” for collection); Ex. 1006 ¶ 148 (same). Our finding is
further supported by the Examiner’s determination that “it would have been
obvious to one having ordinary skill in the art to use a test tube or a PCR
tube as the vessel, as the claimed improvement on a device or apparatus is
no more than ‘the simple substitution of one known element for another or
the mere application of a known technique to a piece of prior art ready for
improvement.’” Ex. 1002, 1099 (quoting Ex parte Smith, 83 USPQ2d 1509,
1518–19 (BPAI 2007) (citing KSR, 550 U.S. at 417)). When responding to
the Office Action, Applicant did not challenge this determination. Id.
at 1115.
5. Secondary Considerations
Patent Owner contends that secondary considerations, including long-
felt need, commercial success, praise, and acquiescence and licensing weigh
in favor of a finding of nonobviousness of the ’837 Patent claims. PO.
Resp. 53–59.
a) Presumption of Nexus
Patent Owner asserts that its “ddPCR™ platform . . . practices the
’837 patent.” PO Resp. 53–54. As support for this assertion, Patent Owner
relies on a statement that “[t]he Bio-Rad Digital PCR Systems and/or their
use is covered by claims of U.S. patents,” including the ’837 Patent and
eight other patents. Id. at 54 (citing Ex. 2022 (Patent Owner’s standard
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terms and conditions of sale)). Patent Owner also asserts that “[t]he patented
features from the ‘837 patent are repeatedly referenced in Bio-Rad’s
instruction manuals and are critical to the Bio-Rad products’ workflows.”
Id. (citing Exs. 2010, 2011). Dr. Anna directs us to portions of these
manuals that instruct users how to transfer droplets out of the separation
chamber of a cartridge. Ex. 2016 ¶ 180 (citing Ex. 2010, 18; Ex. 2011, 18).
Based on these assertions, Patent Owner contends that “the secondary
considerations . . . related to Bio-Rad’s products have a sufficient nexus to
the claims of the ‘837 Patent.” PO Resp. 54.
“In order to accord substantial weight to secondary considerations in
an obviousness analysis, the evidence of secondary considerations must have
a nexus to the claims, i.e., there must be a legally and factually sufficient
connection between the evidence and the patented invention.” Fox Factory,
Inc. v. SRAM, LLC, 944 F.3d 1366, 1373 (Fed. Cir. 2019) (internal quotes
omitted); see also Lectrosonics, Inc. v. Zaxcom, Inc., Case IPR2018-01129,
Paper 33 at 32 (PTAB Jan. 24, 2020) (precedential) (“For objective indicia
of nonobviousness to be accorded substantial weight, its proponent must
establish a nexus between the evidence and the merits of the claimed
invention.”). There is a rebuttable presumption of nexus “when the patentee
shows that the asserted objective evidence is tied to a specific product and
that product ‘embodies the claimed features, and is coextensive with them.’”
Fox Factory, 944 F.3d at 1373 (citations omitted); Lectrosonics, Paper 33
at 32.
Patent Owner does not present an analysis demonstrating that its
products are coextensive (or nearly coextensive) with the challenged claims
of the ’837 Patent. At best, Dr. Anna directs us to instructions for
transferring droplets from outlet wells to a PCR plate. Ex. 2016 ¶ 180
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(citing Ex. 2010, 18; Ex. 2011, 18). Even if these instructions were
sufficient to establish that Patent Owner’s products have a “separation
chamber” and a “droplet receiving outlet,” there are numerous other claim
limitations that are not addressed by Patent Owner’s evidence of nexus.
Although Patent Owner relies on its standard terms and conditions listing the
’837 Patent among eight other patents (PO Resp. 54 (citing Ex. 2022)), a
simple patent listing is not enough to show coextensiveness or nexus.
Accordingly, Patent Owner has not shown that its products are
entitled to a presumption of nexus.
b) Patent Owner’s Acquisition of ’837 Patent
Patent Owner asserts that “Bio-Rad acquired RainDance and all of its
intellectual property in January 2017, including the ’837 patent,
demonstrating the value that has been placed on the protected features of the
’837 patent.” PO Resp. 53 (citing Ex. 2014 (press report titled, “Bio-Rad to
Acquire RainDance Technologies”)). Patent Owner does not present
arguments or evidence as to the value that was ascribed to the ’837 Patent or
the technology covered by the challenged claims in the context of Patent
Owner’s acquisition of RainDance. Accordingly, we are not persuaded that
Patent Owner has shown a nexus for this asserted secondary considerations
evidence.
c) Long-Felt Need
Patent Owner asserts that “RainDance’s patented droplet system,
which included features embodied in the ‘837 patent, fundamentally
enhances the way researchers and scientists study cell-based and cell-free
biomarkers in cancer, infectious disease, and inherited disorders.” PO
Resp. 55 (citing Ex. 2016 ¶ 182).
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According to Patent Owner, its “ddPCR™ platform was heralded as a
breakthrough that greatly advanced the capabilities of PCR” and was
“rapidly adopted in the industry and led to an explosion of research.” PO
Resp. 55 (citing Exs. 2001–2004). Based on this evidence, Patent Owner
contends that “[t]he inventions of the ‘837 patent fulfilled a long-term need
for a means of isolating sample from the surrounding environment for
further analysis using microfluidic droplets by means of the claimed
separation chamber.” Id. at 56 (citing Ex. 2016 ¶¶ 183–186).
“A finding that a presumption of nexus is inappropriate does not end
the inquiry into secondary considerations.” Fox Factory, 944 F.3d at 1375;
Lectrosonics, Paper 33 at 33. “To the contrary, the patent owner is still
afforded an opportunity to prove nexus by showing that the evidence of
secondary considerations is the ‘direct result of the unique characteristics of
the claimed invention.’” Fox Factory, 944 F.3d at 1373–74 (quoting In re
Huang, 100 F.3d 135, 140 (Fed. Cir. 1996)); Lectrosonics, Paper 33 at 33.
Patentee must show a “nexus to the merits of the claimed invention,”
meaning “some aspect of the claim not already in the prior art.”
Lectrosonics, Paper 33 at 33 (quoting In re Kao, 639 F.3d 1057, 1068–69
(Fed. Cir. 2011)).
We determine that Patent Owner has not demonstrated a nexus
between the evidence relied upon to show long-felt need and the merits of
the claimed invention. Patent Owner asserts that the evidence touts its
ddPCR™ platform as “an easy-to-use alternative to the existing technology”
that enabled researchers to publish numerous studies and “to detect rare
targets with a level of precision that was just not possible with previous
technologies.” PO Resp. 55–56 (citing Exs. 2001–2004). Patent Owner
makes no attempt to show a nexus between the technology discussed in
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Exhibits 2001 to 2004 and the features recited in the challenged claims of
the ’837 Patent.
d) Commercial Success
Patent Owner contends that its products that embody the ’837 Patent
have been a commercial success, with the inventions disclosed in the ’837
Patent contributing to this success and representing “a significant
improvement on the prior art that greatly advanced the capability of PCR
and NGS [Next Generation Sequencing].” PO Resp. 56 (citing
Exs. 2005–2009; Ex. 2016 ¶ 187).
Patent Owner also contends that Petitioner’s “products embodying the
invention have been a commercial success.” PO Resp. 56–57 (citing and
quoting Ex. 2012 (discussing number of instruments sold in total and to “top
research institutions” and “global pharmaceutical companies” and associated
revenue increases as of December 31, 2018 and June 30, 2019)).
For the reasons discussed above, Patent Owner has not shown that its
products are entitled to a presumption of nexus. Nor has Patent Owner
shown a nexus between the merits of the claimed invention and the evidence
relied upon to show commercial success of its products or Petitioner’s
products. Although Patent Owner relies on Exhibits 2005 to 2009 and 2012,
it does not show a nexus between this evidence and the unique features of
the challenged claims.
e) Praise by Others
Patent Owner asserts that its ddPCR™ products have received
“repeated accolades for their contributions to the field” and that its
“ddSEQ™ system has also received wide acclaim.” PO Resp. 57–58 (citing
Exs. 2005–2009). According to Patent Owner, “prior to its acquisition by
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Bio-Rad, Raindance received praise from the industry for its own systems
that incorporated the patented features of the ‘837 patent.” Id. at 58 (citing
Exs. 2023–2026). Petitioner asserts that both Patent Owner’s and
Petitioner’s products “have received praise because of their turn-key, easy-
to-use workflows.” Id. at 59 (citing Ex. 2013).
For the reasons discussed above, Patent Owner has not shown that its
products are entitled to a presumption of nexus. Nor has Patent Owner
shown a nexus between the merits of the claimed invention and the evidence
relied upon to show industry praise of Patent Owner’s products,
RainDance’s products, or Petitioner’s products. Although Patent Owner
relies on Exhibits 2005–2009, 2013, and 2023–2026, it does not show a
nexus between this evidence and the unique features of the challenged
claims. Furthermore, although Patent Owner discusses advantages of the
patented inventions (PO Resp. 59), Patent Owner does not show that these
advantages are the reasons Patent Owner’s and Petitioner’s products have
received praise. Nor does Patent Owner show that the evidence of industry
praise or other asserted secondary considerations is tied to the novel features
of the claimed invention or the claimed combination as a whole. WBIP, LLC
v. Kohler Co., 829 F.3d 1317, 1331 (Fed. Cir. 2016); Lectrosonics, Paper 33
at 33.
6. Conclusion for Ground 2
We conclude that Petitioner has shown by a preponderance of the
evidence that claims 1, 2, 4, 7, 9–13, 19, and 20 are unpatentable as obvious
over Ismagilov 091 and Quake.
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F. Petitioner’s Grounds 3–5: Ismagilov 119 alone or in view of Pamula
Petitioner contends that claims 1–4, 7–13, and 19–20 are unpatentable
as obvious over Ismagilov 119, alone or in view of Pamula. Pet. 56–71.
We first provide an overview of the asserted references and then turn to the
parties’ contentions and our analysis.
1. Ismagilov 119 (Ex. 1005)
Ismagilov 119 is a U.S. Patent Publication titled “Microfluidic
System.” Ex. 1005, codes (10), (54). Petitioner asserts that Ismagilov 119 is
prior art to the ’837 Patent under 35 U.S.C. § 102(a)(2) and pre-AIA
§ 102(e) as of its March 16, 2005 filing date and under § 102(a)(1) and pre-
AIA § 102(a) as of its May 4, 2006 publication date. Pet. 13–14. Patent
Owner does not contest the prior art status of Ismagilov 119. We find that
Ismagilov 119 is prior art to the ’837 Patent, regardless of whether the AIA
applies to the patent.
Ismagilov 119 discloses a microfluidic system. Ex. 1005, code (54).
Ismagilov 091 is incorporated by reference into Ismagilov 119. Id. ¶¶ 30,
118. Like Ismagilov 091, Ismagilov 119 refers to droplets as “plugs.” Id.
¶ 22, Fig. 13b (showing “aqueous droplets, or plugs” being formed at the
junction between “channel a” through which an aqueous stream is pumped
and “channel b” though which a carrier fluid is pumped).
Petitioner relies on the following passage from Ismagilov 119:
Plugs can be sorted. For example, the plugs can also be
sorted according to their sizes. Alternately, the plugs can be
sorted by their density relative to that of the carrier fluid.
Alternately, plugs can also be sorted by applying a magnetic field
if one group of the plugs contains magnetic materials such as iron
or cobalt nanoparticles or ferrofluid.
Ex. 1005 ¶ 123.
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2. Pamula 634 (Ex. 1007); Pamula 238 (Ex. 1018)
Pamula 634 and Pamula 238 are U.S. Patent Publications, both of
which are titled “Droplet-based Surface Modification and Washing.”
Ex. 1007, codes (10), (54); Ex. 1018, codes (10), (54).
Petitioner asserts that Pamula 634 is prior art to the ’837 Patent under
35 U.S.C. § 102(a)(2) and pre-AIA § 102(e) as of its December 15, 2006
filing date. Pet. 15. This assertion is based on Petitioner’s contention that
the ’837 Patent claims are not supported by the provisional priority
applications filed before Pamula 634’s filing date. Pet. 15–16.
Petitioner asserts that Pamula 238 is prior art to the ’837 Patent under
35 U.S.C. § 102(a)(2) and pre-AIA § 102(e) as of the April 18, 2006 filing
date of a provisional application.14 Pet. 16. According to Petitioner, the
disclosures relied upon by Petitioner “are substantially identical between the
publication and provisional” and “Pamula 238 includes claims supported by
that provisional.” Id. (citing Ex. 1018 ¶ 418; Ex. 1025, 8–9).
Patent Owner does not contest the prior art status of Pamula 634 or
Pamula 238. We do not decide whether Petitioner has shown that either
Pamula 634 or Pamula 238 is prior art to the ’837 Patent because, for the
reasons discussed below, we find that Petitioner has not established
unpatentability based on the grounds that include these references.
Pamula 634 and Pamula 238 (collectively “Pamula”)15 disclose a
droplet microactuator. Ex. 1007, code (57), ¶¶ 3, 13, 374, Fig. 1.

14 Ex. 1025, U.S. Provisional Application No. 60/745,058 (“Pamula 058”).
15 For the sake of simplicity, we cite only to Pamula 634 (Ex. 1007).
Pamula 238 (Ex. 1018) contains the same disclosures as we cite in
Pamula 634 (Ex. 1007).
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By way of background, Pamula discusses two types of microfluidic
systems. Ex. 1007 ¶ 12. According to Pamula, “continuous-flow systems
rely on continuous flow of liquids in channels whereas discrete-flow systems
utilize droplets of liquid either within channels or in a channel-less
architecture.” Id. Pamula identifies various limitations of continuous-flow
systems. Id. Pamula indicates that a need remains for a system that uses
droplet manipulations to carry out multiple tests on a single chip and that can
be integrated into a handheld device for use at the point of sample collection,
e.g., for bedside blood analysis. Id. ¶¶ 11, 12.
Pamula’s droplet microactuator includes a substrate with electrodes
arranged in arrays, paths, or networks for transporting droplets along the
path or network of electrodes. Ex. 1007 ¶¶ 375–381. The droplet
microactuator may include a pair of parallel substrates separated by a gap
with an array of electrodes on one or both substrates. Id. ¶¶ 205, 377, Fig. 6.
In that case, “droplets may be interposed in the space between the plates,”
and the “[s]pace surrounding the droplets typically includes a filler fluid.”
Id. ¶ 378. According to Pamula, “[t]he droplet microactuator operates by
direct manipulation of discrete droplets, e.g., using electrical fields.” Id.
¶ 381.
Pamula states that “[d]iscrete droplet operations obviate the necessity
for continuous-flow architecture and all the various disadvantages that
accompany such an architecture.” Ex. 1007 ¶ 385. Nevertheless, Pamula
discloses that “[t]he droplet microactuator may in some cases be
supplemented by continuous flow components” and that “such combination
approaches involving discrete droplet operations and continuous flow
elements are within the scope of the invention.” Id. Pamula states that “in
certain other embodiments, various continuous flow elements are
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specifically avoided in the droplet microactuator.” Id. Pamula discloses
“microchannels” as an exemplary component that may be excluded from a
droplet microactuator. Id.
Petitioner relies on paragraph 418 of Pamula, which discloses in
relevant part:
The filler fluid may be selected to have a particular density
relative to the droplet phase. A difference in density between the
two phases can be used to control or exploit buoyancy forces
acting upon the droplets. Examples of two-phase systems useful
in this aspect of the invention include water/silicone oil,
water/flourinert [sic, fluorinert], and water/fluorosilicone oil.
When one phase is buoyant, then that effect can be exploited in
a vertical configuration as a means to transport one phase through
the other. For example, a waste or collection well can exist at
the top or bottom of the droplet microactuator where droplets are
delivered to that reservoir by simply releasing them at an
appropriate point and allowing them to float or sink to the target
destination. Such an approach may be suitable for use in
removing reactant from a droplet microactuator, e.g. removing
fluid containing amplified nucleic acid for use in other processes.
Ex. 1007 ¶ 418.
3. Ground 3: Ismagilov 119 Alone
Claim element 1.3 recites: “at least one downstream separation
chamber comprising a droplet receiving chamber inlet and at least one
droplet receiving outlet.” Ex. 1001, 88:10–12.
Petitioner contends that claim element 1.3 is rendered obvious by
Ismagilov 119’s disclosure that “the plugs can be sorted by their density
relative to that of the carrier fluid.” Pet. 57 (quoting Ex. 1005 ¶ 123). More
specifically, Petitioner contends:
Based on the knowledge of one of ordinary skill, a POSA
would already be familiar with the features of a system to sort
droplets based on density. As described in section VI [of the
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Petition], droplets either float (cream) or sink (sediment) if they
were placed in a large vessel such that the droplets and
continuous phase liquid could move freely past each other if they
had different densities. The above quote from Ismagilov 119
described a density difference between the carrier fluid and the
droplets. Also, there was a density difference based on the fluids
disclosed in Ismagilov, as described in section VI, and a POSA
could have observed the droplets floating in the oil. The
chamber itself would be a large volume to collect multiple
droplets and allow them to move freely through the continuous
oil phase to form a fraction enriched for droplets, as was well-
known for emulsions. A chamber or reservoir would need to
extend vertically to permit the density sorting to occur over the
distance parallel with the force of gravity. For the chamber to
operate to remove the fraction of floating droplets, an outlet is
placed at the top of the chamber to collect the droplets. This
would allow the droplet enriched fraction to be collected, which
would mean that substantially only droplets would be entering
the outlet. There would also be an outlet on the bottom for
unwanted fluids (e.g., immiscible fluid) to exit and avoid it
overflowing into the outlet for the droplets.
The space of the chamber would be enclosed except for
the inlet and outlet to allow the droplets to be extracted (e.g.,
from the top of the chamber).
Id. at 57–58 (citing Ex. 1008 ¶¶ 136–144) (emphasis added).
Petitioner’s contention is an attempt to extrapolate from a single
sentence in Ismagilov 119—“the plugs can be sorted by their density relative
to that of the carrier fluid”—a teaching or suggestion of a separation
chamber comprising a droplet receiving chamber inlet and at least one
droplet receiving outlet, as recited in claim element 1.3. In our view,
however, this single sentence cited from Ismagilov 119 does not identify any
particular structure at all, much less the recited “separation chamber” having
a “droplet receiving chamber inlet” and a “droplet receiving outlet.”
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In our view, Petitioner’s analysis improperly relies on hindsight and
conclusory assertions about the knowledge of a POSA to supply multiple
important claim limitations that are missing from the cited disclosure of
Ismagilov 119. See KSR, 550 U.S. at 421 (in reaching a conclusion of
obviousness, “hindsight bias and must be cautious of arguments reliant upon
ex post reasoning” must be avoided); DSS Tech. Mgmt. v. Apple Inc., 885
F.3d 1367, 1374 (Fed. Cir. 2018) (“In cases in which ‘common sense’ is
used to supply a missing limitation, as distinct from a motivation to
combine, . . . our search for a reasoned basis for resort to common sense
must be searching.”); Arendi S.A.R.L. v. Apple Inc., 832 F.3d 1355, 1367
(Fed. Cir. 2016) (reversing Board’s determination of obviousness where “the
missing limitation is not a ‘peripheral’ one, and there is nothing in the record
to support the Board’s conclusion that supplying the missing limitation
would be obvious to one of skill in the art”).
Petitioner misreads the sentence it relies upon as the lynchpin of its
obviousness contention. Ismagilov 119 discloses that “plugs can be sorted
by their density relative to that of the carrier fluid.” Ex. 1005 ¶ 123.
Dr. Fair opines “[t]his means that, based on the difference in densities
between the droplets and the carrier fluid, the droplets are substantially
separated from the carrier fluid.” Ex. 1008 ¶ 136. According to Petitioner
and Dr. Fair, this passage “refers to only two things in the sorting: the
droplets that are referred to as having one density, and the carrier fluid that is
referred to as having a different relative density.” Pet. 57; Ex. 1008 ¶ 136.
We disagree with the hindsight-based interpretation advanced by
Petitioner and Dr. Fair. The sentence from Ismagilov 119, paragraph 123
describes sorting plugs, not separating plugs from carrier fluid. Our
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understanding is consistent with the entirety of Ismagilov 119,
paragraph 123, which reads:
Plugs can be sorted. For example, the plugs can also be
sorted according to their sizes. Alternately, the plugs can be
sorted by their density relative to that of the carrier fluid.
Alternately, plugs can also be sorted by applying a magnetic field
if one group of the plugs contains magnetic materials such as iron
or cobalt nanoparticles or ferrofluid.
Ex. 1005 ¶ 123. Paragraph 123 begins with the general statement that
“[p]lugs can be sorted.” Id. Each sentence that follows that general
statement is an “example” of how plugs can be sorted. Id. Accordingly,
sorting plugs “by their density relative to that of the carrier fluid” is
reasonably interpreted to mean separating the plugs from each other based
on their density relative to the carrier fluid, as opposed to separating plugs
from the immiscible fluid. For example, plugs that float in the carrier fluid
can be sorted from plugs that sink in the carrier fluid without separating the
plugs from the carrier fluid.
Petitioner’s obviousness case hinges on the proposition that a POSA
would have understood that a “separation chamber” would be necessary to
carry out the “sorting by density” that is described in Ismagilov 119. See,
e.g., Pet. 57–60; Ex. 1008 ¶ 140 (“a person of ordinary skill in the art would
know that all that would be required to perform such density-based sorting
would be a relatively simple chamber with a sufficiently large volume to
collect multiple droplets and allow them to move freely through the
continuous oil phase to form a separate fraction enriched for droplets”).
In our view, Petitioner’s evidence does not justify a leap from density-
based sorting, as disclosed in Ismagilov 119, to a “separation chamber” in
which droplets are separated from immiscible fluid, as recited in claim 1.
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Petitioner directs us to no disclosure or suggestion, either in Ismagilov 091
or Ismagilov 119, that the density-based sorting mentioned in paragraph 123
takes place in a chamber or reservoir. Moreover, Ismagilov 091 suggests
that sorting occurs in microchannels, not in a separation chamber. Ex. 1004,
17:10–13 (“A variety of channels for sample flow and mixing can be
fabricated on the substrate and can be positioned at any location on the
substrate, chip, or device as the detection and discrimination or sorting
points.”); id. at 21:55–59 (“[O]ne or more plugs are detected, analyzed,
characterized, or sorted dynamically in a flow stream of microscopic
dimensions based on the detection or measurement of a physical or chemical
characteristic, marker, property, or tag.”) (emphases added). As such,
Petitioner has not shown that Ismagilov 119 teaches a separation chamber
comprising a droplet receiving chamber inlet and at least one droplet
receiving outlet, as recited in claim element 1.3.
For these same reasons, Petitioner has not shown that Ismagilov 119
describes a separation chamber that is “is upright to the microchannel and
out of the horizontal plane” as required by claim element 1.4, that “has a
wider cross-section than the microchannel cross-section” as recited in claim
element 1.6, or that “is of a volume sufficient to separate the plurality of
droplets . . . from the immiscible fluid . . . ” as recited in claim element 1.7.
Ex. 1001, 88:10–14, 88:18–23; Pet. 64, 66–67.
The foregoing analysis for Ground 3 is essentially the same as set
forth in our Institution Decision. Inst. Dec. 44–48. Patent Owner agrees
with our analysis. PO Resp. 59–60. Petitioner presents two reply
arguments. Pet. Reply 27–28.
First, Petitioner argues that we “misread Ismagilov 119’s disclosure of
sorting plugs/droplets” and that the first and third examples in paragraph 123
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refer to sorting plugs from other plugs, e.g., “‘according to their sizes’
(plural)” and the second example refers “to only a singular ‘density’ of all
plugs relative to the carrier fluid.” Pet. Reply 27. We disagree. In our view,
Petitioner places too much emphasis on the difference between the plural
(sizes) and the singular (density). As discussed above, all three examples
fall under the general statement that “[p]lugs can be sorted,” which
Petitioner does not dispute means sorting plugs from other plugs. Ex. 1005
¶ 123. Petitioner’s argument does not change our view that each sentence
that follows that general statement is an “example” of how plugs can be
sorted from other plugs. Id.
Second, Petitioner argues that “a POSA would recognize the need for
a structure that would arrive at the density sorter of Grounds 3a/3b-5a/5b”
and “[t]his is not an application of hindsight.” Pet. Reply 27–28 (citing
Pet. 56–71; Ex. 1008 ¶¶ 102, 108–114, 135–149, 155–159; Ex. 1071
¶¶ 46–55). We are not persuaded by Petitioner’s reply argument for both
procedural and substantive reasons.
Regarding procedure, we agree with Patent Owner (PO Sur-reply
19–20) that Petitioner’s Reply improperly incorporates argument by
referring to eight pages from Dr. Fair’s second declaration (Exhibit 1071)
into the page-and-a-half of the Reply that addresses Grounds 3–5. Compare
Pet. Reply 27–28, with Ex. 1071 ¶¶ 46–55. See 37 C.F.R. § 42.6(a)(3)
(“Arguments must not be incorporated by reference from one document into
another document.”). Paragraph 50 of Dr. Fair’s second declaration
discusses how and why droplets separate from a continuous phase, providing
opinions that are not discussed in Petitioner’s Reply. Paragraph 53 of
Dr. Fair’s second declaration discusses whether Ismagilov 119’s
microchannels can be used as a density sorting structure, again providing
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opinions that are not discussed in Petitioner’s Reply. Paragraph 54 of
Dr. Fair’s second declaration discusses why a POSA would have combined
the relevant teachings of Ismagilov 119 and Pamula, again providing
opinions that are not discussed in Petitioner’s Reply. Paragraph 55 of
Dr. Fair’s second declaration discusses the impact of Patent Owner’s
proposed claim constructions on Dr. Fair’s opinions concerning Grounds
3–5, again providing opinions that are not discussed in Petitioner’s Reply.
We do not consider these portions of Dr. Fair’s second declaration that are
not discussed in Petitioner’s Reply.
We are also not persuaded by the substance of Petitioner’s reply
argument. Petitioner argues that a POSA would have known that “multiple
droplets would be pooled in the vertical chamber.” Pet. Reply 27 (citing
Ismagilov 119 ¶ 123). As stated above and in the Institution Decision (Inst.
Dec. 48), Petitioner directs us to no disclosure or suggestion, either in
Ismagilov 091 or Ismagilov 119, that the density-based sorting mentioned in
paragraph 123 takes place in a chamber or reservoir. Moreover,
Ismagilov 091 suggests that sorting occurs in microchannels, not in a
separation chamber. See id.; Ex. 1004, 17:10–13, 21:55–59. Petitioner does
not address whether the density-based sorting mentioned in Ismagilov 119
paragraph 123 refers to sorting that occurs in microchannels.
We conclude that Petitioner has not shown that claims 1–4, 7–13, and
19–20 are unpatentable based on Ismagilov 119 alone.
4. Grounds 4 and 5: Ismagilov 119 and Pamula
Petitioner contends that a POSA would have combined
Ismagilov 119’s teaching of “density separation” with Pamula’s description
of “sorting droplets based on a difference in density between the droplets
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and the carrier fluid.” Pet. 60–61 (citing Ex. 1007 ¶ 418; Ex. 1018 ¶ 418;
Ex. 1025, 8–9). More specifically, Petitioner contends that a “POSA would
have been able to apply Pamula’s teachings of a density separation chamber
with an outlet (collection well) at the top to Ismagilov’s system which itself
already included the use of both outlet wells and density-based sorting of
droplets from oil.” Pet. 61; Ex. 1008 ¶ 156 (same).
We are not persuaded by Petitioner’s unpatentability contentions
based on Ismagilov 119 and Pamula for several reasons.
First, Petitioner has not shown a reason why a skilled artisan would
have combined the teachings of Ismagilov 119 and Pamula absent the use of
impermissible hindsight. In contrast to Ismagilov 119, which discloses that
droplets “can be sorted by their density relative to that of the carrier fluid”
(Ex. 1005 ¶ 123), Pamula does not disclose sorting droplets. Instead,
Pamula discloses separating aqueous droplets from the filler phase, e.g.,
silicone oil, by allowing them to float or sink to a target destination. See,
e.g., Ex. 1007 ¶ 418. In view of these differences, Petitioner’s combination
appears to be motivated by impermissible hindsight, rather than reasoning
that would have been employed by a POSA who had not seen claim 1 and
the supporting disclosure of the ’837 Patent. In re Gorman, 933 F.2d 982,
987 (Fed. Cir. 1991) (“It is impermissible . . . simply to engage in a
hindsight reconstruction of the claimed invention, using the applicant’s
structure as a template and selecting elements from references to fill the
gaps.”).
Second, it is unclear whether Petitioner contends that a POSA would
have used Pamula’s vertical collection well: (1) as Ismagilov 119’s density
sorter or (2) as Ismagilov 119’s outlet well. See Pet. 61; Ex. 1008 ¶ 156.
Either way, Petitioner and Dr. Fair do not explain sufficiently how and why
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a POSA would have combined Ismagilov 119’s channel-based flow
elements with Pamula’s discrete-flow system and vertical collection well.
See Metalcraft of Mayville, Inc. v. Toro Co., 848 F. 3d 1358, 1367 (Fed. Cir.
2017) (“Without any explanation as to how or why the references would be
combined to arrive at the claimed invention, we are left with only hindsight
bias that KSR warns against.”).
Third, Petitioner’s contention that a POSA “would have been able to
apply Pamula’s teachings . . . to Ismagilov’s system” (Pet. 61; Ex. 1008
¶ 156, emphasis added) is improperly “focused on what a skilled artisan
would have been able to do, rather than what a skilled artisan would have
been motivated to do at the time of the invention.” Polaris Indus., Inc. v.
Arctic Cat, Inc., 882 F.3d 1056, 1068 (Fed. Cir. 2018).
The foregoing analysis for Grounds 4 and 5 is essentially the same as
set forth in our Institution Decision. Inst. Dec. 49–50. Patent Owner agrees
with our analysis. PO Resp. 60–61. In reply, Petitioner presents the
arguments addressed above for Ground 3. In addition, Petitioner argues that
“[i]f additional structural information is required for either density-based
sorting, a POSA would have been motivated to look to Pamula for the
structure of a device that operated based on the droplet/oil density
difference, and nothing precludes using Pamula’s waste and collection wells
for droplets.” Pet. Reply 28 (citing Pet. 29–30, 60–64; Ex. 1008
¶¶ 113–114, 155–158). In our view, Petitioner’s reply argument suffers
from the same deficiencies discussed above.
We conclude that Petitioner has not shown that claims 1–4, 7–13, and
19–20 are unpatentable as obvious over Ismagilov 119 and Pamula.
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III. CONCLUSION
In summary:16
Claims
35
U.S.C.
§
Reference(s)
Claims
Shown
Unpatentable
Claims
Not Shown
Unpatentable
1, 2, 4, 10–
13, 19, 20
102 Ismagilov 091
1, 2, 4, 10–13,
19, 20

1, 2, 4, 7,
9–13, 19,
20
103
Ismagilov 091,
Quake
1, 2, 4, 7, 9–13,
19, 20

1–4, 7–13,
19, 20
103
Ismagilov 119
1–4, 7–13, 19,
20
1–4, 7–13,
19, 20
103 Ismagilov 119,
Pamula 634
1–4, 7–13, 19,
20
1–4, 7–13,
19, 20
103 Ismagilov 119,
Pamula 238
1–4, 7–13, 19,
20
Overall
Outcome

1, 2, 4, 7, 9–13,
19, 20
3, 8

16 Should Patent Owner wish to pursue amendment of the challenged claims
in a reissue or reexamination proceeding subsequent to the issuance of this
decision, we draw Patent Owner’s attention to the April 2019 Notice
Regarding Options for Amendments by Patent Owner Through Reissue or
Reexamination During a Pending AIA Trial Proceeding, 84 Fed. Reg.
16,654 (Apr. 22, 2019). If Patent Owner chooses to file a reissue application
or a request for reexamination of the challenged patent, we remind Patent
Owner of its continuing obligation to notify the Board of any such related
matters in updated mandatory notices. See 37 C.F.R. § 42.8(a)(3), (b)(2).
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IV. ORDER
In consideration of the foregoing, it is hereby:
ORDERED that Petitioner has shown by a preponderance of the
evidence that claims 1, 2, 4, 7, 9–13, 19, and 20 of the ’837 Patent are
unpatentable;
FURTHER ORDERED that Petitioner has not shown by a
preponderance of the evidence that claims 3 and 8 of the ’837 Patent are
unpatentable; and
FURTHER ORDERED that because this Decision is final, a party to
the proceeding seeking judicial review of the Decision must comply with the
notice and service requirements of 37 C.F.R. § 90.2.
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For PETITIONER:

Samantha A. Jameson
Matthew D. Powers
Azra Hadzimehmedovic
Aaron M. Nathan
Robert L. Gerrity
Gina Cremona
Daniel M. Radke
TENSEGRITY LAW GROUP LLP
samantha.jameson@tensegritylawgroup.com
matthew.powers@tensegritylawgroup.com
azra@tensegritylawgroup.com
aaron.nathan@tensegritylawgroup.com
robert.gerrity@tensegritylawgroup.com
gina.cremona@tensegritylawgroup.com
daniel.radke@tensegritylawgroup.com

For PATENT OWNER:

David Bilsker
Kevin Johnson
Anne Toker
James Baker
John McCauley
QUINN EMANUEL URQUHART & SULLIVAN, LLP
davidbilsker@quinnemanuel.com
kevinjohnson@quinnemanuel.com
annetoker@quinnemanuel.com
jamesbaker@quinnemanuel.com
johnmccauley@quinnemanuel.com