       NOTE: This disposition is nonprecedential.


  United States Court of Appeals
      for the Federal Circuit
                ______________________

          PALO ALTO NETWORKS, INC.,
                  Appellant

                           v.

                    FINJAN, INC.,
                       Appellee
                ______________________

                      2017-2059
                ______________________

    Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in Nos. IPR2015-
02001, IPR2016-00157, IPR2016-00955, IPR2016-00956.
                 ______________________

             Decided: September 19, 2018
               ______________________

    ORION ARMON, Cooley LLP, Broomfield, CO, argued
for appellant.

    PAUL J. ANDRE, Kramer Levin Naftalis & Frankel
LLP, Menlo Park, CA, argued for appellee. Also repre-
sented by JAMES R. HANNAH.
                ______________________
2                   PALO ALTO NETWORKS, INC.   v. FINJAN, INC.



    Before REYNA, SCHALL, and STOLL, Circuit Judges.
STOLL, Circuit Judge.
    Appellant Palo Alto Networks, Inc. petitioned for two
inter partes reviews of Appellee Finjan, Inc.’s U.S. Patent
No. 8,225,408, alleging that certain claims were un-
patentable as obvious. The Patent Trial and Appeal
Board of the U.S. Patent and Trademark Office (“Board”)
found that there was insufficient evidence that Palo Alto
Networks’s proposed prior art combinations would have
taught the “dynamically building” claim limitation. Palo
Alto Networks, Inc., No. IPR2015-02001, 2017 WL
1052502, at *4–10 (P.T.A.B. Mar. 17, 2017) (“Board
Decision”). Therefore, the Board found that Palo Alto
Networks failed to carry its burden of demonstrating, by a
preponderance of the evidence, that any of the challenged
claims would have been obvious. Id. Palo Alto Networks
appeals. We affirm.
                             I
     Finjan’s ’408 patent relates to methods and systems
for detecting malware in data streamed from a network
onto a computer. The patent relates to network security,
including scanning code to determine whether there are
potential viruses in the code. The patent describes a
scanner system that preferably uses generic architecture,
is language-independent, and is customized for a specific
language by using a set of language-specific rules. The
’408 patent explains that this adaptive rule-based scanner
has three components (illustrated in Figure 2, below).
Tokenizer 210 recognizes and identifies constructs (i.e.,
“tokens”) within a byte source code. For example, code
between { } or [ ] would become a token. Parser 220
controls the process of scanning incoming content, prefer-
ably by building a parse tree data structure that repre-
sents the incoming content. Finally, analyzer 230 checks
for malware by searching for specific patterns of content
that indicate malware.
PALO ALTO NETWORKS, INC.   v. FINJAN, INC.               3




’408 patent, Fig. 2.
    Claims 1, 3–7, 9, 12–16, 18–23, 29, and 35 are at issue
in this appeal, and independent claim 1 is illustrative:
    1. A computer processor-based multi-lingual
    method for scanning incoming program code,
    comprising:
    receiving, by a computer, an incoming stream of
    program code;
    determining, by the computer, any specific one of
    a plurality of programming languages in which
    the incoming stream is written;
    instantiating, by the computer, a scanner for the
    specific programming language, in response to
    said determining, the scanner comprising parser
    rules and analyzer rules for the specific program-
    ming language, wherein the parser rules define
    certain patterns in terms of tokens, tokens being
    lexical constructs for the specific programming
    language, and wherein the analyzer rules identify
4                   PALO ALTO NETWORKS, INC.   v. FINJAN, INC.



    certain combinations of tokens and patterns as be-
    ing indicators of potential exploits, exploits being
    portions of program code that are malicious;
    identifying, by the computer, individual tokens
    within the incoming stream;
    dynamically building, by the computer while said
    receiving receives the incoming stream, a parse
    tree whose nodes represent tokens and patterns in
    accordance with the parser rules;
    dynamically detecting, by the computer while said
    dynamically building builds the parse tree, com-
    binations of nodes in the parse tree which are in-
    dicators of potential exploits, based on the
    analyzer rules; and
    indicating, by the computer, the presence of po-
    tential exploits within the incoming stream, based
    on said dynamically detecting.
Id. claim 1 (emphasis added to highlight the disputed
claim limitation). We focus on the claim limitation requir-
ing “dynamically building” a parse tree, which is common
to all the challenged claims. The Board construed “dy-
namically building” to mean: “requires that a time period
for dynamically building overlap with a time period
during which the incoming stream is being received.”
Board Decision, 2017 WL 1052502, at *3. This unopposed
claim construction was proposed by Palo Alto Networks
based on the plain claim language, which requires “dy-
namically building, by the computer while said receiving
receives the incoming stream.” ’408 patent, claim 1.
                             II
    Palo Alto Networks asserted that claims 1, 3–5, 9, 12–
16, 18, 19, 22, 23, 29, and 35 of the ’408 patent would
have been obvious over U.S. Patent No. 7,636,945
(“Chandnani”) and U.S. Patent No. 5,860,011 (“Kolawa”)
PALO ALTO NETWORKS, INC.   v. FINJAN, INC.               5



under 35 U.S.C. § 103. Palo Alto Networks also asserted
that the same claims would have been obvious over
Chandnani, Kolawa, and U.S. Patent No. 7,284,274
(“Walls”).
    Chandnani teaches a method of detecting malware in
a data stream, including determining the programming
language of the data stream and detecting viral code.
Figure 2 from Chandnani (duplicated below) illustrates
Chandnani’s script language virus detection apparatus,
including detection engine 53, one of the focal points of
Chandnani’s method:




Chandnani, Fig. 2, col. 8 ll. 5–7. Detection engine 53
tokenizes the incoming data stream by breaking it into
smaller pieces known as tokens. As part of that process,
it receives the language check data from the language
description module 55, as indicated in step 31 of Figure 6:
6                   PALO ALTO NETWORKS, INC.   v. FINJAN, INC.




Id. at Fig. 6, col. 7 ll. 61–63. The language check data is
used to lexically analyze the data stream at step 33 to
determine the appropriate script language. Id. at col. 7
ll. 63–65. At step 35, the language definition data for the
script language determined in step 33 is retrieved from
language description module 55. Id. at col. 7 ll. 65–67.
Using the language definition data retrieved at step 35,
the data stream is lexically analyzed for a second time to
generate the stream of tokens at step 37. Id. at col. 7
l. 67–col. 8 l. 3 (“the data stream is again lexically ana-
lyzed to generate a stream of tokens” (emphasis added)).
PALO ALTO NETWORKS, INC.   v. FINJAN, INC.                7



   Chandnani provides the following summary of the to-
kenizing procedure, explaining the function of its “lexical
analyzer”:
    To tokenize the data stream, a script language
    used in the data stream is determined using the
    language check data. The data stream is analyzed
    using the language check data to select the lan-
    guage definition data to use for the detection pro-
    cess. Next, the selected language definition data
    and the data stream are supplied to the lexical
    analyzer. The data stream is lexically analyzed
    again, this time using the language definition da-
    ta, to generate a stream of tokens. As mentioned
    above, each generated token corresponds to a spe-
    cific language construct, and may be a correspond-
    ing unique number or character.
Id. at col. 8 ll. 7–17 (emphases added).
     The Board determined that the dispositive issue was
whether Palo Alto Networks demonstrated, by a prepon-
derance of the evidence, that the prior art teaches or
suggests “dynamically building” a parse tree “while”
receiving an incoming stream of program code. Specifical-
ly, the parties disputed whether Chandnani discloses that
the time period for generating the token stream overlaps
with the time period for receiving the incoming stream, as
required by the Board’s construction of “dynamically
building.”
    The Board found that Chandnani does not teach the
“dynamically building” limitation of the ’408 patent
because it does not demand or even imply that the data
stream is being received while being tokenized. In sup-
port of its conclusion, the Board cited testimony of Fin-
jan’s expert, Dr. Nenad Medvidovic.       Ultimately, the
Board concluded that Palo Alto Networks had not demon-
strated, by a preponderance of the evidence, that the
combination of Chandnani and Kolawa would have taught
8                   PALO ALTO NETWORKS, INC.   v. FINJAN, INC.



or suggested “dynamically building” a parse tree “while”
receiving an incoming stream of program code. The Board
likewise concluded that Palo Alto Networks had not
demonstrated, by a preponderance of the evidence, that
the combination of Chandnani, Kolawa, and Walls teach-
es or suggests “dynamically building” a parse tree “while”
receiving an incoming stream of program code. The Board
found that Finjan had failed to carry its burden of show-
ing that the instituted prior art disclosed the “dynamical-
ly building” limitation. Accordingly, it did not consider
evidence of secondary considerations of nonobviousness,
including expert testimony from Finjan’s expert,
Dr. Harry Bims, on that issue.
   Palo Alto Networks appeals. We have jurisdiction
pursuant to 28 U.S.C. § 1295(a)(4)(A).
                            III
    Obviousness under 35 U.S.C. § 103 is a mixed ques-
tion of law and fact. 1 We review the Board’s ultimate
obviousness determination de novo and its underlying
fact-findings for substantial evidence. Harmonic Inc. v.
Avid Tech., Inc., 815 F.3d 1356, 1363 (Fed. Cir. 2016).
“Substantial evidence is something less than the weight of
the evidence but more than a mere scintilla of evidence,”
meaning that “[i]t is ‘such relevant evidence as a reasona-
ble mind might accept as adequate to support a conclu-



    1   Congress amended § 103 when it enacted the
Leahy–Smith America Invents Act (‘‘AIA’’). Pub. L.
No. 112-29, § 3(c), 125 Stat. 284, 287 (2011). Because the
application that led to the ’408 patent has never contained
(1) a claim having an effective filing date on or after
March 16, 2013, or (2) a reference under 35 U.S.C. §§ 120,
121, or 365(c) to any patent or application that ever
contained such a claim, the pre-AIA § 103 applies. See id.
§ 3(n)(1), 125 Stat. at 293.
PALO ALTO NETWORKS, INC.   v. FINJAN, INC.                 9



sion.’” In re NuVasive, Inc., 842 F.3d 1376, 1379–80
(Fed. Cir. 2016) (quoting In re Applied Materials, Inc.,
692 F.3d 1289, 1294 (Fed. Cir. 2012)).
    As a preliminary matter, the parties do not dispute
the Board’s definition of a person of ordinary skill in the
art as having a bachelor’s degree or equivalent experience
in computer science or related academic fields, and three
to four years of additional experience in the field of com-
puter security, or equivalent work experience.
                              A
    On appeal, Palo Alto Networks challenges the Board’s
reading of Chandnani. In particular, Palo Alto Networks
asserts that the Board erred in finding that Chandnani
does not teach “dynamically building” a parse tree while
receiving an incoming stream of program code.
     We hold that the Board’s finding is supported by sub-
stantial evidence because the reference itself, by using the
word “again,” indicates that the data stream is lexically
analyzed more than once and not simultaneously.
Chandnani teaches using “language check data to lexical-
ly analyze the data stream to determine the appropriate
script language” and that “[u]sing the language definition
data . . . the data stream is again lexically analyzed to
generate a stream of tokens.” Chandnani, col. 7 l. 60–
col. 8 l. 3 (emphasis added). The Board was also entitled
to credit the testimony of Dr. Medvidovic, who opined that
“simply because Chandnani’s tokenizer operates on a data
stream does not demand or even imply that the data
stream is being received while being tokenized.” Board
Decision, 2017 WL 1052502, at *8 (quoting J.A. 3091–92,
¶ 74 (citing Chandnani, col. 9 ll. 12–16, col. 7 l. 60–col. 8
l. 17, Fig. 6)).   Dr. Medvidovic further testified that
“Chandnani would still temporarily store the entire data
stream in memory at least between the first and second
lexical analyses.” J.A. 3092 ¶ 74. His testimony supports
the Board’s conclusion that a person of ordinary skill,
10                  PALO ALTO NETWORKS, INC.   v. FINJAN, INC.



reviewing Chandnani, would not have understood it to
teach “dynamically building” a parse tree.
    We appreciate Palo Alto Networks’s argument and its
expert’s testimony that speed is critical to malware detec-
tion and that “delaying analysis of a file obtained from a
network until the entire file is received would have been
viewed as creating unnecessary delay for the user and
subjecting the receiving computer to risk of damage due to
execution of stored malware files.” Appellant’s Br. at 40;
see also id. at 8–11. The issue before us, however, is
whether the Board’s reading of Chandnani is supported
by “such relevant evidence as a reasonable mind might
accept as adequate to support” the Board’s conclusion.
NuVasive, 842 F.3d at 1379–80. Based on plain language
quoted above from Chandnani’s specification, we conclude
that it is supported by such substantial evidence. See id.
    Palo Alto Networks next challenges the Board’s
treatment of Walls, a prior art reference Palo Alto relied
on in the alternative for disclosure of the “dynamically
building” limitation. Palo Alto argues that the Board
erred by analogizing Walls to Chandnani and by not
meaningfully reviewing Walls as a separate reference
that discloses the dynamically building limitation. In its
Final Written Decision, the Board noted that Palo Alto
Networks’s “challenges based on the combination of Walls
with Chandnani and Kolawa suffer from the same defi-
ciencies as its challenges based on Chandnani and Kola-
wa alone, in that [it] does not sufficiently establish that
the prior art it relies on discloses the temporal interleav-
ing required by our construction of ‘dynamically build-
ing.’” Board Decision, 2017 WL 1052502, at *8. In so
holding, the Board considered the disclosure of Walls and
the expert testimony regarding Walls from both parties.
It also performed its own review of Walls and ultimately
concluded that Palo Alto Networks had not demonstrated,
by a preponderance of the evidence, that the combination
of Chandnani, Kolawa, and Walls teaches or suggests
PALO ALTO NETWORKS, INC.   v. FINJAN, INC.               11



“dynamically building” a parse tree “while” receiving an
incoming stream of program code. Accordingly, we con-
clude that, contrary to Palo Alto Network’s assertion, the
Board did not fail to meaningfully consider the teachings
of Walls.
                              B
    Finally, Palo Alto Networks asserts that the Board
erred by not considering particular cross-examination
testimony from Finjan’s expert witnesses when analyzing
whether the prior art taught “dynamically building.”
Before trial, Finjan had moved to exclude this particular
cross-examination testimony of its experts, Dr. Medvidov-
ic and Dr. Bims. The Board denied Finjan’s motion.
Instead, the Board explained that it would consider
Finjan’s arguments “as going to the weight that should be
given to the cross-examination testimony,” not its admis-
sibility. Board Decision, 2017 WL 1052502, at *10. In its
Final Written Decision, the Board stated that it had
“considered and weighed the testimony provided by
Dr. Medvidovic,” but that it had “not relied on the testi-
mony of Dr. Bims in reaching [its] decision.” Id. Palo
Alto Networks argues that the Board failed to meaning-
fully consider the testimony from both witnesses.
    First,   Palo     Alto    Networks      protests    that
Dr. Medvidovic’s cross-examination testimony was not
substantively discussed in the Board’s decision. Palo Alto
Networks cites Google Inc. v. Intellectual Ventures II LLC,
701 F. App’x 946 (Fed. Cir. 2017), where this court held in
a nonprecedential opinion that it could not review the
Board’s findings because it could not discern, from the
Board’s opinion, the scope of “all evidence and arguments”
considered by the Board. Google, 701 F. App’x at 954.
Here, however, it was clear why Dr. Medvidovic’s testi-
mony would not have been convincing. More elaboration
was not required.            The Board acknowledged
Dr. Medvidovic’s cross-examination testimony and ex-
12                   PALO ALTO NETWORKS, INC.   v. FINJAN, INC.



plained its reasoning for why Chandnani does not disclose
the required claim limitation, even having considered
Palo Alto Networks’s counterarguments:
     [T]o the extent that Chandnani discloses different
     embodiments directed to the underlying identifi-
     cation of the file to be scanned—whether stored on
     a hard or floppy disk, or received via a network—
     Chandnani still requires multiple passes through
     the file, first to determine the appropriate script
     language and then to lexically analyze the data
     stream to generate the stream of tokens.
Board Decision, 2017 WL 1052502, at *8 (Mar. 17, 2017)
(citing Chandnani Fig. 6; J.A. 3090–92). Indeed, as we
held in PGS Geophysical AS v. Iancu, even while “we may
not supply a reasoned basis for the agency’s action that
the agency itself has not given, we will uphold a decision
of less than ideal clarity if the agency’s path may reason-
ably be discerned.” 891 F.3d 1354, 1365 (Fed. Cir. 2018)
(citing Bowman Transp., Inc. v. Arkansas–Best Freight
Sys., Inc., 419 U.S. 281, 286 (1974); NuVasive, 842 F.3d
at 1383). As in PGS, we think that the Board did not fail
to address the question at hand. We therefore affirm.
     Second, Palo Alto Networks argues that the Board
gave no rationale for not relying on Dr. Bims’s cross-
examination testimony. The Board, having found that
Finjan had failed to carry its burden of showing that the
instituted prior art disclosed the “dynamically building”
limitation, did not reach the issue of secondary considera-
tions of nonobviousness. Therefore, it was not necessary
for the Board to consider Dr. Bims’s testimony, which was
limited to the issue of secondary considerations of nonob-
viousness. Accordingly, we find no error in the Board’s
decision not to consider Dr. Bims’s testimony, and we
conclude that the Board sufficiently explained its ra-
tionale for declining to do so.
PALO ALTO NETWORKS, INC.   v. FINJAN, INC.           13



                              IV
    We have considered the parties’ remaining argu-
ments, including Palo Alto Networks’s arguments regard-
ing “temporal interleaving,” and find them unpersuasive.
We affirm the Board’s decision.
                        AFFIRMED
                           COSTS
   Costs to Appellee.
