CAFC critiques PTAB Arista decision for lack of explanation of reasoning

Lack of reasoning by PTAB (as to why certain prior art was inadequate
to teach a claim element) produced a vacating in the Arista case:


Arista Networks, Inc. challenged various claims of
Cisco Systems, Inc.’s U.S. Patent No. 8,051,211 in an
inter partes review. The Patent Trial and Appeal Board
of the Patent and Trademark Office determined that
Arista failed to show that certain claims are unpatentable
for obviousness. Because the Board did not adequately
explain its reasoning on a point that was central to its
analysis, we vacate the Board’s determination as to the
appealed claims and remand for further proceedings.




Of the problem


We agree with Arista that the Board has not adequately
explained its finding that Kunzinger does not
disclose the tunneling limitation of claims 2, 6–9, 13, and
17–20 of the ’211 patent.

(...)

Arista’s contention on appeal is that the Board improperly
overlooked that complication of the “without
examination” portion of the “tunneling” construction when
considering Kunzinger.

(...)

Consequently, Arista concludes, Kunzinger
teaches the “tunneling” limitation, contrary to the Board’s
finding. At the least, Arista contends, the Board did not
adequately explain why Kunzinger’s examining activities,
involving the outer header, are relevantly different from
actions permitted to be part of “tunneling” by the ’211
patent, a crucial premise of the Board’s finding that
Kunzinger does not teach that limitation.





As to legal standards:


We review the Board’s final written decisions “to ensure
that they are not ‘arbitrary, capricious, an abuse of
discretion, . . . otherwise not in accordance with law . . .
[or] unsupported by substantial evidence.’” Pers. Web
Techs., LLC v. Apple, Inc., 848 F.3d 987, 992 (Fed. Cir.
2017) (quoting 5 U.S.C. § 706(2)(A), (E)). “[I]n order to
allow effective judicial review, . . . the agency is obligated
to provide an administrative record showing the evidence
on which the findings are based, accompanied by the
agency’s reasoning in reaching its conclusions.” Id. (quoting
Synopsys, Inc. v. Mentor Graphics Corp., 814 F.3d
1309, 1322 (Fed. Cir. 2016), overruled in another respect
by Aqua Prods., Inc. v. Matal, 872 F.3d 1290 (Fed. Cir.
2017), and In re Lee, 277 F.3d 1338, 1342 (Fed. Cir. 2002))
(internal quotation marks omitted). “For judicial review
to be meaningfully achieved within these strictures, the
agency tribunal must present a full and reasoned explanation
of its decision.” Lee, 277 F.3d at 1342.

We agree with Arista to the following extent (and we
go no further here): the Board did not adequately explain
why “transmission of the IPSec packet” in Kunzinger
includes an “examination” excluded from the “tunneling”
claimed in the ’211 patent, even while the described use of
fields and tags in the ’211 patent is not such an excluded
“examination.” Final Written Decision, at 25. The ’211
patent’s tunneling process “internally routes data . . .
depending on, for example, information associated with
the data (e.g., an encapsulation tag . . . ).” ’211 patent,
col. 7, lines 38–42. At one level of generality, in that
situation, as in Kunzinger, a portion of a frame is transmitted
through the tunnel without examination, while
another portion is examined to route the data to its proper
destination. That general description of what is similar
may well omit critical differences. The Board implicitly
must have so found in determining that Kunzinger shows
a forbidden “examination.” But the Board’s decision is
lacking in explanation on this key element of its analysis.
The decision “does not address, or at least does not clearly
address,” the difference between the examination of
tunneled packets in Kunzinger and the type of examination
that is permissible in the tunneling process of the
’211 patent. See Pers. Web, 848 F.3d at 993.



The CAFC attempted to lay out a boundary:



Some Board explanations can suffice even if brief, as
when the patent and the art are both clear and readily
understandable. Id. at 994. In addition, “we will uphold
a decision of less than ideal clarity if the agency’s path
may reasonably be discerned.” Bowman Transp., Inc. v.
Ark.–Best Freight Sys., Inc., 419 U.S. 281, 286 (1974); see
In re NuVasive, Inc., 842 F.3d 1376, 1382–83 (Fed. Cir.
2016). But, understood in light of our scrutiny of the
patent and the prior art, the Board’s “own explanation
must suffice for us to see that the agency has done its job
and must be capable of being ‘reasonably . . . discerned’
from a relatively concise [Board] discussion.” In re NuVasive,
842 F.3d at 1383. In this case, Cisco’s attempt to
explain the distinction at issue has not sufficiently enabled
us to see an adequate explanation in the Board’s
opinion.