United States Court of Appeals 

for the Federal Circuit ______________________ 

VIRNETX INC.,

Appellant

v.

APPLE, INC.,

Appellee

______________________ 

2017-2490, 2017-2494

______________________ 

Appeals from the United States Patent and Trademark Office, Patent Trial and Appeal Board in No. 

IPR2016-00331.

______________________ 

Decided: December 10, 2018

______________________ 

IGOR VICTOR TIMOFEYEV, Paul Hastings LLP, Washington, DC, argued for appellant. Also represented by 

NAVEEN MODI, STEPHEN BLAKE KINNAIRD, JOSEPH PALYS,

MICHAEL WOLFE, DANIEL ZEILBERGER. 

 JOHN C. O'QUINN, Kirkland & Ellis LLP, Washington, 

DC, argued for appellee. Also represented by NATHAN S.

MAMMEN; SCOTT BORDER, JEFFREY PAUL KUSHAN, Sidley 

Austin LLP, Washington, DC. 

 ______________________ 
2 VIRNETX INC. v. APPLE, INC. 

Before NEWMAN, O’MALLEY, and CHEN, Circuit Judges.

O’MALLEY, Circuit Judge. 

VirnetX Inc. (“VirnetX”) appeals from two final written decisions of the Patent Trial and Appeal Board 

(“Board”) finding that Apple Inc. (“Apple”) had demonstrated by a preponderance of the evidence that claims 1–

11, 14–25, and 28–30 of U.S. Patent No. 8,504,696 (“the 

’696 patent”) were unpatentable as obvious. VirnetX Inc. 

v. Apple Inc., No. IPR2016-00331 (P.T.A.B. June 22, 2017) 

(“331 Board Decision”); VirnetX Inc. v. Apple Inc., No. 

IPR2016-00332 (P.T.A.B. June 22, 2017) (“332 Board

Decision”). Because VirnetX is collaterally estopped from 

relitigating the threshold issue of whether prior art 

reference RFC 24011 was a printed publication and because VirnetX did not preserve the only remaining issue

of whether inter partes review procedures apply retroactively to patents that were filed before Congress enacted 

the America Invents Act (“AIA”), we affirm. 

I. PROCEDURAL HISTORY

In December 2015, Apple filed two petitions for inter 

partes review of the ’696 patent. In the first petition, 

Apple challenged claims 1–11, 14–25, and 28–30 as obvious over U.S. Patent No. 6,496,867 and RFC 2401. In the 

second petition, Apple challenged these same claims, 

except claim 29, as obvious over various other combinations also involving RFC 2401. The Board instituted inter 

partes review in both proceedings. VirnetX filed patent 

owner responses in which it argued, as a threshold matter, that RFC 2401 was not a printed publication under 

§ 102(b) as of November 1998. In its final written deci-

 

1 S. Kent & R. Atkinson, “RFC 2401, Security Architecture for the Internet Protocol” (November 1998) 

(J.A. 2268).
VIRNETX INC. v. APPLE, INC. 3

sions, the Board found that RFC 2401 was a printed 

publication and concluded that the ’696 patent was unpatentable as obvious. VirnetX appeals. 

During the pendency of VirnetX’s appeal in this case, 

this court decided VirnetX Inc. v. Apple, Inc., No. 17-1131, 

715 F. App’x 1024 (Fed. Cir. Mar. 16, 2018) (“VirnetX I”). 

In VirnetX I, VirnetX appealed seven final written decisions in which the Board found that RFC 2401, in combination with other references, rendered obvious a number 

of patents related to the ’696 patent. In relevant part, 

VirnetX argued to the Board that RFC 2401 was not a 

printed publication as of November 1998. The Board 

disagreed. On March 16, 2018, we summarily affirmed 

the Board’s decisions pursuant to Federal Circuit Rule 36. 

VirnetX I, 715 F. App’x at 1024. 

After the mandate issued in VirnetX I, Apple submitted a notice of supplemental authority in this case, notifying the court of the relevance of our Rule 36 judgment in 

VirnetX I to the present appeal. The issue was also 

discussed by the parties during oral argument. According 

to Apple, VirnetX is collaterally estopped by our judgment 

in VirnetX I from relitigating the printed publication 

issue. VirnetX responds that it is not collaterally estopped, and, even if it were, such a finding would not 

resolve all issues in this appeal because VirnetX preserved a separate constitutional challenge in its opening 

brief. We have jurisdiction pursuant to 28 U.S.C. 

§ 1295(a)(4). 

II. DISCUSSION

A party is collaterally estopped from relitigating an 

issue if: 

(1) a prior action presents an identical issue; (2) 

the prior action actually litigated and adjudged 

that issue; (3) the judgment in that prior action 

necessarily required determination of the identi-
4 VIRNETX INC. v. APPLE, INC. 

cal issue; and (4) the prior action featured full 

representation of the estopped party. 

Stephen Slesinger, Inc. v. Disney Enterprises, Inc., 702 

F.3d 640, 644 (Fed. Cir. 2012). Collateral estoppel or 

“issue preclusion applies where the[se] . . . [elements] of 

collateral estoppel are carefully observed.” B & B Hardware, Inc. v. Hargis Indus., Inc., 135 S. Ct. 1293, 1306

(2015) (quotations omitted). This is no different in the 

context of a Rule 36 judgment. Phil-Insul Corp. v. Airlite 

Plastics Co., 854 F.3d 1344, 1356 (Fed. Cir. 2017). While 

not all Rule 36 judgments will “satisfy those ordinary 

elements, that does not mean none will.” See B & B 

Hardware, 135 S. Ct. at 1306. Accordingly, we have held 

that a Rule 36 judgment may serve as a basis for collateral estoppel so long as these elements—including the 

element that the resolution of the issue was essential or 

necessary to the Rule 36 judgment—are carefully observed. Phil-Insul, 854 F.3d at 1356–57. 

Here, Apple is correct that VirnetX is collaterally estopped by our Rule 36 judgment in VirnetX I from relitigating the question of whether RFC 2401 was a printed 

publication. The parties dispute only the question of 

whether the issue was necessary or essential to the judgment in VirnetX I. We find that it was. Each ground of 

unpatentability that VirnetX appealed in VirnetX I relied 

on RFC 2401. Even VirnetX conceded during oral argument that the printed publication issue was a threshold 

issue in VirnetX I. See Oral Arg. at 5:04, 

http://oralarguments.cafc.uscourts.gov/default.aspx?fl=

2017-2490.mp3 (“[T]he finding that RFC 2401 was a 

printed publication was indeed a threshold issue [in 

VirnetX I] so I think, under that analysis, the court would 

have addressed that question.” (emphasis added)). Indeed, 

in three of the seven final written decisions appealed in 

VirnetX I, the only issue raised was whether RFC 2401 

was a printed publication. Accordingly, by affirming all 

seven of the Board’s decisions, this court in VirnetX I 
VIRNETX INC. v. APPLE, INC. 5

necessarily found that RFC 2401 was a printed publication. Therefore, VirnetX is collaterally estopped by our 

Rule 36 judgment in VirnetX I from relitigating the issue 

in this appeal. 

Even if VirnetX were not collaterally estopped, we 

would affirm the Board’s conclusion that RFC 2401 was a 

printed publication as of November 1998. This is because, 

as VirnetX admits, “this appeal presents a similar record 

with respect to RFC 2401’s status as a printed publication 

as [VirnetX I],” and thus, if we reached the merits, we 

would be “likely to reach the same conclusion in this 

appeal as [we] did in [VirnetX I].” VirnetX’s Resp. to 

Apple’s Notice, ECF No. 43. 

VirnetX next argues that RFC 2401’s status as a 

printed publication is not dispositive of all issues raised in 

this appeal because it preserved in its opening brief the 

separate issue of whether inter partes review procedures

apply retroactively to patents that were filed before 

Congress enacted the AIA. To demonstrate that it preserved this issue, VirnetX points to a single paragraph in 

its Opening Brief, filed prior to the Supreme Court’s 

decision in Oil States Energy Services, LLC v. Greene’s 

Energy Group, LLC, 138 S. Ct. 1365 (2018). In this paragraph, VirnetX asks this court to “set aside the Board’s 

IPR decision” “[i]f the Supreme Court decides[, in Oil 

States,] that the Seventh Amendment and Article III of 

the Constitution preclude the Board from invalidating 

patents through IPR proceedings.” Appellant’s Br. at 54. 

This paragraph explicitly raises the specific question later 

decided in Oil States of whether the “IPR process violates 

the Constitution by extinguishing private property rights 

through a non-Article III forum without a jury.” Appellant’s Br. at 54 (internal quotations omitted). And, under

a very generous reading, the paragraph also arguably 

raises a general challenge under the Seventh Amendment. 

But, we find that it in no way provides any arguments 

specifically preserving the retroactivity issue. 
6 VIRNETX INC. v. APPLE, INC. 

Indeed, VirnetX conceded at oral argument that it 

“didn’t specifically brief” the retroactivity issue. See Oral 

Arg. at 18:01, 

http://oralarguments.cafc.uscourts.gov/default.aspx?fl=20

17-2490.mp3. It attempts to justify this failure by arguing that our precedent prior to Oil States generally upheld 

the constitutionality of inter partes review proceedings 

and thus, foreclosed the argument. But we have never 

decided this issue, and, even if we had, VirnetX never 

sought to provide supplemental briefing or to otherwise 

develop this argument following the Supreme Court’s 

decision in Oil States. Rather, VirnetX insists it preserved this issue by way of a single, generic paragraph. It 

did so only after Apple filed its notice of supplemental 

authority identifying our Rule 36 judgment in VirnetX I, 

which VirnetX acknowledges significantly weakens an 

otherwise dispositive issue in this appeal.2 All of this 

suggests that VirnetX’s insistence is likely less than 

sincere. Thus, we conclude that VirnetX did not preserve 

the issue of whether inter partes review procedures apply 

retroactively to patents that were filed before Congress 

enacted the AIA and that, therefore, our conclusion that 

VirnetX is collaterally estopped from raising the printed 

publication issue resolves all other issues in this appeal.3

 

2 Despite acknowledging this, VirnetX chose to pursue this appeal through oral argument. But on November 

28, 2018, VirnetX filed an opposed motion to dismiss this 

appeal in which it expressly admitted for the first time 

that our Rule 36 judgment in VirnetX I has collateral 

estoppel effect in this case and any future cases in which 

this issue is raised. We denied the motion. 3 The other issues VirnetX raises on appeal are issues appealed from the 332 Board Decision. Our finding 

of collateral estoppel disposes of those issues even though 
VIRNETX INC. v. APPLE, INC. 7

CONCLUSION

Because VirnetX is collaterally estopped from raising 

a threshold question in this case and because that issue is 

dispositive of all issues preserved on appeal, we affirm the 

Board’s conclusion that claims 1–11, 14–25, and 28–30 of 

the ’696 patent were unpatentable as obvious. 

AFFIRMED

COSTS

Costs to Appellee. 

 

they do not relate to RFC 2401 or to its status as a printed publication. This is because, in the 331 Board Decision, the Board found unpatentable every claim that it 

found unpatentable in the 332 Board Decision. And, the 

only issue VirnetX appeals from the 331 Board Decision is 

the printed publication issue, which we now uphold. 

Because we affirm the Board’s ultimate conclusion in the 

331 Board Decision that the challenged claims are unpatentable as obvious, we need not address any additional 

issues VirnetX raises in its appeal from the 332 Board 

Decision regarding those same claims.