Streck, Inc., Streck LLC v. Ravgen, Inc.

N OTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
STRECK, INC., STRECK LLC,
Appellants
v.
RAVGEN, INC.,
Appellee
______________________
2023-1989
______________________
Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. IPR2021-
01577.
______________________
Decided: January 22, 2025
______________________
T HOMAS L EE D USTON, Marshall, Gerstein & Borun
LLP, Chicago, IL, argued for appellants. Also represented
by T HOMAS BURNS , S ANDIP P ATEL , I SHA S. SHAH .
BRIAN MATTY , Desmarais LLP, New York, NY, argued
for appellee. Also represented by J OHN M. D ESMARAIS ,
K ERRI-A NN L IMBEEK; G ABRIELLE E. HIGGINS , San Fran-
cisco, CA.
______________________
Case: 23-1989 Document: 87 Page: 1 Filed: 01/22/2025

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STRECK, INC. v. RAVGEN, INC. 2
Before L OURIE, BRYSON, and STARK, Circuit Judges.
L OURIE, Circuit Judge.
Streck LLC1 (“Streck”) appeals from a final decision of
the U.S. Patent Trial and Appeal Board (“the Board”) hold-
ing that all challenged claims of U.S. Patent 7,332,277
(“the ’277 patent”) were not shown to have been obvious.
Streck, Inc. v. Ravgen, Inc., No. IPR2021-01577, (P.T.A.B.
April 18, 2023) (holding that claims 55–61, 68, 69, 80–86,
89–92, 94, 126–130, 132, and 133 had not been shown to be
unpatentable) (“Decision”). For the following reasons, we
affirm.
BACKGROUND
The instant case is a companion case to Laboratory
Corporation of America Holdings, v. Ravgen, Inc., No.
2023–1342, –1136, 2025 WL 32904 (Fed. Cir. Jan. 6, 2025)
(“Labcorp”) addressing the same patent and decided by this
court on January 6, 2025. In that case, we affirmed the
upholding of an overlapping set of claims against different
prior art. As in that case, claims 55 and 132 are illustrative
for the issues on appeal.
Claim 55 reads as follows:
55. A method comprising determining the sequence
of a locus of interest on free fetal DNA isolated from
a sample obtained from a pregnant female, wherein
said sample comprises free fetal DNA and an agent
that inhibits lysis of cells, if cells are present,
wherein said agent is selected from the group con-
sisting of membrane stabilizer, cross-linker, and
cell lysis inhibitor.
’277 patent, col. 472, l. 66–col. 473, l. 5.
1 Streck LLC is the successor in interest to Streck,
Inc.
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STRECK, INC. v. RAVGEN, INC. 3
Claim 132 reads as follows:
132. The method of claim 60, wherein said cell lysis
inhibitor is selected from glutaraldehyde, formal-
dehyde, and formalin.
Id. at col. 478, ll. 12–14.
Streck asserted unpatentability based on three
grounds in its inter partes review petition; however, only
the Board’s decision with respect to obviousness over Pertl2
in combination with Granger3 is challenged on appeal.
Streck’s Pertl-Granger combination also relied on back-
ground teachings of Chiu4 to establish a motivation to com-
bine the references. Pertl reports a study on a fetal DNA
detection method that can be used to detect both male and
female fetal DNA from a maternal blood sample. J.A.
3038–42. Granger discloses a method for preserving blood
samples for later analysis using formaldehyde. J.A. 3054–
58. Chiu reports a study on the effects of blood-processing
protocols on fetal and total DNA quantification in maternal
plasma. J.A. 3043–49.
The Board determined that none of the challenged
claims had been shown to be obvious over Pertl and
Granger. Decision, at J.A. 87. The Board found that a per-
son of ordinary skill in the art would not have been
2 Pertl et al., Detection of Male and Female Fetal
DNA in Maternal Plasma by Multiplex Fluorescent Poly-
merase Chain Reaction Amplification of Short Tandem Re-
peats, 106 HUM . G ENETICS 45 (2000) (“Pertl”), J.A. 3038–
42. 3 Granger et al., WO 97/45729, published Dec. 4,
1997 (“Granger”), J.A. 3050–96.
4 Chiu et al., Effects of Blood-Processing Protocols on
Fetal and Total DNA Quantification in Maternal Plasma,
47 CLINICAL CHEMISTRY 1607 (2001) (“Chiu”), J.A. 3043–
49.
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STRECK, INC. v. RAVGEN, INC. 4
motivated to combine the prior art references because
“Pertl does not express concerns that cell lysis would inter-
fere with its method or report increased background DNA
released due to lysis (contrary to Petitioner’s assertion).”
Id. at J.A. 67. The Board also concluded that a person of
ordinary skill in the art “would have had significant and
unresolved concerns about expanding formaldehyde’s use
to applications involving rare circulating cell-free fetal
DNA in maternal plasma as such use could damage the
cffDNA analyte in the sample itself.” Id. at J.A. 87. The
Board credited expert testimony that “such concerns would
have dissuaded a [person of ordinary skill in the art] from
modifying Pertl’s method with Granger’[s] formaldehyde as
proposed by [Streck].” Id. Streck timely appealed, and we
have jurisdiction under 28 U.S.C. § 1295(a)(4)(A).
D ISCUSSION
On appeal, Streck argues that the Board committed a
variety of legal errors and that its findings were not sup-
ported by substantial evidence. In response, Ravgen de-
fends the Board’s decision and further asserts that Streck
lacks standing to appeal the Board’s final written decision.
I
We begin with the standing issue. To meet Article III
standing requirements, the party seeking relief “must have
(1) suffered an injury in fact, (2) that is fairly traceable to
the challenged conduct of the defendant, and (3) that is
likely to be redressed by a favorable judicial decision.”
Spokeo, Inc. v. Robins, 578 U.S. 330, 338 (2016). To estab-
lish an injury in fact sufficient to appeal a final written de-
cision of the Board, an appellant “need not meet all the
normal standards for redressability and immediacy.” Grit
Energy Sols., LLC v. Oren Techs., LLC, 957 F.3d 1309, 1319
(Fed. Cir. 2020) (cleaned up). It is generally sufficient for
the appellant to show that “it has engaged in, is engaging
in, or will likely engage in activity that would give rise to a
possible infringement suit.” Id. (cleaned up).
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STRECK, INC. v. RAVGEN, INC. 5
Ravgen argues that Streck lacks Article III standing to
appeal the Board’s decision because it cannot show the re-
quired injury in fact. Ravgen Br. 22–27. Streck responds
that infringement accusations by Ravgen and Streck’s cus-
tomers’ indemnity demands both establish injury in fact
under the proper standard. Reply Br. 2–7.
The facts of this case clearly establish a genuine risk of
an infringement suit against Streck. Ravgen filed an ex-
pert report with the Board that includes claim charts and
an express accusation of both direct and indirect infringe-
ment of its patent by Streck. J.A. 14219 (“[I]t is my opinion
that Streck’s use of Cell-Free DNA BCT (‘Streck BCT’)
meets each and every limitation of, and therefore practices,
Claims 55, 59–60, 81, 89–91, and 132–133 of the ’277 Pa-
tent. Additionally, Streck induces third parties to practice
the method of Claims 55, 59–60, 81, 89–91, and 132–133 of
the ’277 Patent.”); see also J.A. 14219–323 (claim charts).
Additionally, Ravgen has sued multiple Streck customers
alleging infringement of the ’277 patent. See Reply Br. 3
n.1. The claim charts and accompanying statements filed
with the Board, coupled with Ravgen’s history of filing in-
fringement suits against Streck’s customers, establish the
risk of an infringement suit against Streck sufficient to
grant standing to appeal a final written decision of the
Board.
Because the risk of an infringement suit is clear, we
need not determine if Streck’s customers’ indemnity de-
mands independently grant Streck standing to appeal the
Board’s decision.
II
Having determined that Streck possesses standing to
appeal the Board’s decision, we now address Streck’s argu-
ments relating to the Board’s obviousness determination.
Obviousness is a question of law based on underlying find-
ings of fact. KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 427
(2007). We review the Board’s legal conclusion on
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STRECK, INC. v. RAVGEN, INC. 6
obviousness de novo and its findings of fact for substantial
evidence. HTC Corp. v. Cellular Commc’ns Equip., LLC,
877 F.3d 1361, 1369 (Fed. Cir. 2017). What a reference
teaches and the presence or absence of a motivation to com-
bine references are questions of fact. PAR Pharm., Inc. v.
TWI Pharms., Inc., 773 F.3d 1186, 1196–97 (Fed. Cir.
2014).
A
Streck raises a variety of legal challenges to the
Board’s analysis of motivation to combine, but they all sim-
ilarly mischaracterize the Board’s analysis. For example,
Streck argues that the Board erred by requiring Granger’s
solution to be superior to other techniques. Streck Br. 40–
45. However, the Board expressly stated that it was doing
no such thing. See Decision at J.A. 75 (“To be clear, we are
not suggesting that a [person of ordinary skill in the art]
must choose only the ‘best’ solution to prove obviousness.”).
Similarly, Streck argues that the Board erred by requiring
Pertl alone to disclose a motivation to combine the refer-
ences and finding that it discouraged improvement upon
its method. Streck Br. 29–34. However, the Board com-
mitted no such legal error and simply disagreed with
Streck about the teachings of Pertl. See, e.g., Decision at
J.A. 64 (“[W]e find that [Streck] overstates Pertl’s alleged
concerns with ‘background’ maternal DNA and misstates
the purported ‘increases’ in background DNA from cell lysis
in Pertl’s method.”).
As in the companion case, Streck’s arguments “attempt
to recast factual issues as legal ones.” See Labcorp, 2025
WL 32904, at *2. At bottom, the Board made factual deter-
minations regarding what the references teach and the
presence or absence of a motivation to combine. See, e.g.,
Decision, at J.A. 69 (“[W]e are not persuaded the [person of
ordinary skill in the art] would have understood from Chiu
that up to 25% cffDNA was available in maternal blood for
analysis. . . . [T]he prevailing view at the time of Chiu’s
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STRECK, INC. v. RAVGEN, INC. 7
publication, and for years afterward, was that circulating
cell-free fetal DNA in maternal plasma varied from be-
tween about 3–6%.”); id. at J.A. 76 (“We find that Sriniva-
san provides strong evidence that formaldehyde was
known to have detrimental effects on nucleic acids.”). And,
as in the companion case, “disagreement with the Board’s
interpretations of [a reference] does not amount to a
demonstration that the Board somehow failed to use the
proper analysis.” Eli Lilly & Co. v. Teva Pharms. Int’l
GmbH, 8 F.4th 1331, 1347 (Fed. Cir. 2021). We have con-
sidered Streck’s additional legal arguments and find them
similarly flawed.
B
Finally, Streck argues that the Board’s findings were
not supported by substantial evidence. Specifically, Streck
argues that “[n]o evidence supports the finding that a [per-
son of ordinary skill in the art] would have been dissuaded
from using Granger’s formaldehyde solution in Pertl’s
method.” Streck Br. 45. We disagree.
The Board’s conclusions were adequately supported.
The Board credited documentary evidence that “formalde-
hyde induces DNA degradation.” Decision, at J.A. 77. It
also relied on Ravgen’s expert’s testimony to find that these
issues “would have discouraged [formaldehyde’s] use in a
modified Pertl method.” Id. The Board concluded that the
disclosures of Granger did not alleviate those concerns be-
cause Streck’s expert “admit[ed] that Granger describes
‘intracellular nucleic acids,’ that Granger ‘does not disclose
any interactions between its stabilizers and nucleic acids,’
and that Granger is ‘silent on cell-free nucleic acids.’” Id.
at J.A. 83 (original emphasis). These findings were reason-
able and are adequate to support its conclusion that Streck
failed to demonstrate that a person of ordinary skill in the
art would have been motivated to combine Pertl and
Granger to arrive at the claimed invention. See id. at J.A.
87.
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STRECK, INC. v. RAVGEN, INC. 8
CONCLUSION
We have considered Streck’s remaining arguments and
find them unpersuasive. For the foregoing reasons, we af-
firm the Board’s decision in IPR2021-01577.
AFFIRMED
Case: 23-1989 Document: 87 Page: 8 Filed: 01/22/2025

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