Case: 22-2234 Document: 36 Page: 1 Filed: 10/20/2023
NOTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
VIRNETX INC.,
Appellant
v.
CISCO SYSTEMS, INC.,
Appellee
______________________
2022-2234
______________________
Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. 95/001,851.
______________________
Decided: October 20, 2023
______________________
STEPHEN BLAKE KINNAIRD, Paul Hastings LLP, Wash-
ington, DC, argued for appellant. Also represented by
NAVEEN MODI, JOSEPH PALYS, IGOR VICTOR TIMOFEYEV,
DANIEL ZEILBERGER.
ADAM LLOYD ERICKSON, Haynes and Boone, LLP,
Plano, TX, argued for appellee. Also represented by
THEODORE M. FOSTER, Denver, CO; DEBRA JANECE
MCCOMAS, DAVID L. MCCOMBS, Dallas, TX.
______________________
Case: 22-2234 Document: 36 Page: 2 Filed: 10/20/2023
2 VIRNETX INC. v. CISCO SYSTEMS, INC.
Before LOURIE, BRYSON, and CHEN, Circuit Judges.
CHEN, Circuit Judge.
This patent appeal relates to an inter partes reexami-
nation of U.S. Patent No. 7,418,504 (’504 patent) owned by
VirnetX Inc. (VirnetX). In VirnetX Inc. v. Cisco Systems,
Inc., we vacated the Patent Trial and Appeal Board’s
(Board) initial decision affirming an Examiner’s rejection
of dependent claims 5, 12, and 13 and remanded to the
Board with instructions to “consider whether the Lenden-
mann reference 1 discloses the use of its [remote procedure
call (RPC)] mode of communication for communications be-
tween a user and the [Cell Directory Service (CDS)] as
found by the Examiner.” 776 F. App’x 698, 704 (Fed. Cir.
2019) (footnote added) (VirnetX I). On remand, the Board
rejected claims 5, 12, and 13 again and denied rehearing.
Cisco Sys. Inc. v. VirnetX Inc., Reexamination
No. 95/001,851, Appeal No. 2017-010954, 2022 WL 909849,
at *4 (P.T.A.B. Mar. 24, 2022) (Board Decision); Cisco Sys.
Inc. v. VirnetX Inc., Reexamination No. 95/001,851, Appeal
No. 2017-010954, 2022 WL 2866398, at *3–4 (P.T.A.B.
July 19, 2022) (Decision on Rehearing). VirnetX appeals.
Because the Board supported its reasoning with substan-
tial evidence, adequately explained its reasoning, and ade-
quately responded to VirnetX’s arguments, we affirm.
BACKGROUND
As we discussed at length in VirnetX I, 2 the ’504 patent
is directed to a domain name service system that facilitates
1 Rolf Lendenmann, Understanding OSF DCE 1.1
for AIX and OS/2, IBM International Technical Support
Organization, pp. 1–245 (Oct. 1995), J.A. 4428–703.
2 We assume familiarity with the prior procedural
history of this case, including our opinion in VirnetX I, and
discuss only the facts relevant to resolving the disputes
raised in this latest appeal.
Case: 22-2234 Document: 36 Page: 3 Filed: 10/20/2023
VIRNETX INC. v. CISCO SYSTEMS, INC. 3
secure communication links between devices in a computer
network. 776 F. App’x at 700. In VirnetX I, we vacated the
Board’s affirmance of the Examiner’s rejection of depend-
ent claims 5, 12, and 13, the only claims at issue in the pre-
sent appeal. Id. at 704. We could not affirm that Board
decision because the Board had failed to make a key factual
finding regarding “whether the Lendenmann reference dis-
closes the use of its RPC mode of communication for com-
munications between a user and the CDS” even though this
fact was disputed by VirnetX and critical to the Examiner’s
rejection. Id.
On remand, the Board determined that “the Exam-
iner’s finding that Lendenmann uses the RPC mode of com-
munication between a user and the CDS is supported by a
preponderance of the evidence.” Board Decision, 2022 WL
909849, at *2. The Board rejected VirnetX’s arguments
that Lendenmann’s CDS does not use RPC. Id. Citing and
quoting several passages in Lendenmann in support of its
position, the Board reasoned:
Lendenmann discloses “[i]n OSF [open software
foundation] DCE [distributed computer environ-
ment], data sharing is built upon RPC [remote pro-
cedure call], which is used as the means of
transferring data . . . . [T]he directory service . . .
[is] based upon the data sharing model.” Lenden-
mann discloses the RPC application includes RPC
runtime, which “performs such tasks as controlling
communications between clients and servers or
finding servers for clients on request.” Lenden-
mann discloses “[t]he RPC runtime can be used to
store and search for the location of servers (binding
information) in the directory service.” Thus, the Ex-
aminer’s finding that Lendenmann uses the RPC
mode of communication between a user and the
CDS is supported by a preponderance of the evi-
dence.
Case: 22-2234 Document: 36 Page: 4 Filed: 10/20/2023
4 VIRNETX INC. v. CISCO SYSTEMS, INC.
Id. (all alterations, omissions, and emphases in original)
(citations omitted) (citing J.A. 4627, 4631, 4639, 4643,
4660–61). The Board equally applied this reasoning to
claims 5, 12, and 13 in accordance with our holding in Vir-
netX I and affirmed the Examiner’s rejection of these
claims. Id. at *2–4.
VirnetX requested rehearing, and the Board denied
this request. Decision on Rehearing, 2022 WL 2866398, at
*1, *3. According to the Board, the passages of Lenden-
mann that VirnetX relied on “d[id] not outweigh or limit
the express disclosures of Lendenmann” that were cited by
the Board in Board Decision. Id. at *2. The Board further
explained that:
[VirnetX], in acknowledging that the CDS is in-
volved in RPC communication, but arguing that
RPC is not involved until after the request to the
CDS has already been made, does not discuss or
acknowledge the express disclosures in Lenden-
mann cited in [Board Decision]: 1) the system uses
RPC to transfer data in the data sharing model
upon which the CDS is based, and 2) RPC runtime
performs tasks such as finding servers for clients
on request and searching for the location of servers
in the directory service.
Id. at *3.
VirnetX appealed. We have jurisdiction under 35
U.S.C. § 141(b) and 28 U.S.C. § 1295(a)(4)(A).
DISCUSSION
VirnetX challenges the Board’s finding that Lenden-
mann’s CDS uses the RPC mode of communication, a find-
ing that, as we articulated in VirnetX I, was necessary to
the Examiner’s rejection of each of claims 5, 12, and 13.
776 F. App’x at 702–03. On appeal, VirnetX alleges the
Board failed to (1) support its reasoning with substantial
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VIRNETX INC. v. CISCO SYSTEMS, INC. 5
evidence, (2) adequately explain its determination, and
(3) adequately consider VirnetX’s arguments. We disagree.
First, substantial evidence supports the Board’s affir-
mance of the Examiner’s rejection of claims 5, 12, and 13.
The Board found Lendenmann expressly teaches (1) using
RPC to transfer data in the data sharing model upon which
the CDS is based and (2) using RPC runtime to perform
tasks such as finding servers for clients on request and
searching for the location of servers in the directory service
(which includes the CDS). See Decision on Rehearing, 2022
WL 2866398, at *3; Board Decision, 2022 WL 909849, at *2
(citing J.A. 4627, 4631, 4639, 4643, 4660–61). Rather than
directly contending with the Board’s findings, VirnetX re-
peatedly points to examples elsewhere in Lendenmann al-
legedly establishing that the CDS is merely involved in the
process of making an RPC and that the RPC is executed
only after the request to the CDS has already been made.
See, e.g., Appellant’s Br. 19, 21, 24; Appellant’s Reply Br. 4,
7. VirnetX, however, does not reconcile its position with
the Board’s contrary understanding of Lendenmann or
meaningfully address the specific portions of Lendenmann
relied on by the Board. VirnetX does not explain, for ex-
ample, how the Board’s finding that Lendenmann teaches
using RPC runtime to search for locations of servers in the
directory service does not indicate that Lendenmann dis-
closes using the RPC mode of communication for communi-
cations between a user and the CDS. VirnetX fails to
persuade us that the Board’s findings lack substantial evi-
dence.
Second, the Board adequately explained its reasoning.
The Board identified and quoted parts of Lendenmann sup-
porting its determination that a preponderance of evidence
supports the Examiner’s finding that Lendenmann teaches
using the RPC mode of communication for communications
between a user and the CDS. Board Decision, 2022 WL
909849, at *2 (citing J.A. 4627, 4631, 4639, 4643, 4660–61).
The Board explained that Lendenmann’s directory service
Case: 22-2234 Document: 36 Page: 6 Filed: 10/20/2023
6 VIRNETX INC. v. CISCO SYSTEMS, INC.
uses the data sharing model and that the data sharing
model in turn uses RPC as a means of transferring data.
Id. at *2. The Board also explained that Lendenmann
teaches using RPC runtime to search for locations of serv-
ers in the directory service. Id. From this explanation, we
find that “the [Board]’s path may reasonably be discerned”
and thus hold that the Board adequately explained its find-
ings. Alacritech, Inc. v. Intel Corp., 966 F.3d 1367, 1370
(Fed. Cir. 2020) (quoting In re NuVasive, Inc., 842 F.3d
1376, 1382–83 (Fed. Cir. 2016)).
Third, the Board adequately responded to VirnetX’s ar-
gument that Lendenmann’s CDS does not use RPC. Vir-
netX’s appeal brief to the Board argued that Lendenmann
expressly teaches steps for executing an RPC in which first,
“the client queries a CDS to find a compatible server,” sec-
ond, “the CDS delivers to the client a partly bound or fully
bound handle with the address information of the server,”
and third, “[t]he client then makes an RPC to the server.”
J.A. 2308 (citing J.A. 4638). Based on these steps, VirnetX
understood Lendenmann as only teaching that the CDS is
involved in the process of making an RPC, not that the CDS
sends or receives an RPC. Id. The Board’s decision on re-
mand acknowledged VirnetX’s argument but nonetheless
found the Examiner and Cisco’s positions to be more per-
suasive in light of other express disclosures in Lenden-
mann. See Board Decision, 2022 WL 909849, at *2. The
Board’s decision on rehearing further explained that it did
not find VirnetX’s arguments sufficient to outweigh the ev-
idence presented in Board Decision. Decision on Rehear-
ing, 2022 WL 2866398, at *2. This constitutes “reasoning
in sufficient detail to permit meaningful appellate review.”
Power Integrations, Inc. v. Lee, 797 F.3d 1318, 1327 (Fed.
Cir. 2015). We therefore conclude the Board adequately
addressed VirnetX’s arguments.
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VIRNETX INC. v. CISCO SYSTEMS, INC. 7
CONCLUSION
We accordingly are not persuaded that the Board erred
in finding that Lendenmann discloses using the RPC mode
of communication for communications between a user and
the CDS. We have considered VirnetX’s remaining argu-
ments and find them unpersuasive. For the foregoing rea-
sons, we affirm the Board’s affirmance of the Examiner’s
rejection of claims 5, 12, and 13.
AFFIRMED