Valve Corporation v. Ironburg Inventions Ltd.

N OTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
VALVE CORPORATION,
Appellant
v.
IRONBURG INVENTIONS LTD.,
Appellee
______________________
2023-1725
______________________
Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. IPR2017-
00858.
______________________
Decided: April 23, 2025
______________________
P ATRICK A. L UJIN, Shook, Hardy & Bacon, LLP, Kansas
City, MO, argued for appellant. Also represented by K YLE
E. F RIESEN, Houston, TX.
G REGORY S. T AMKIN, Dorsey & Whitney LLP, Denver,
CO, argued for appellee.
______________________
Before L OURIE, D YK, and P ROST , Circuit Judges.
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 2
Opinion for the court filed by Circuit Judge D YK.
Opinion concurring in the result filed by Circuit Judge
P ROST .
D YK, Circuit Judge.
Valve Corporation (“Valve”) appeals a final written de-
cision of the Patent Trial and Appeal Board (“Board”) in
inter partes review (“IPR”) 2017-00858. The Board con-
cluded that claims 18, 19, 21, 26, and 29 of U.S. Patent
No. 9,289,688 (the “’688 patent”) were not shown to be un-
patentable as obvious.
In a previous appeal from the same IPR, we affirmed
the Board’s determination that independent claim 1 of the
’688 patent was unpatentable as anticipated, and we deter-
mined, contrary to the Board, that the Burns reference was
prior art. See Valve Corp. v. Ironburg Inventions Ltd.,
8 F.4th 1364, 1381 (Fed. Cir. 2021) (Valve I). We then re-
manded the case to the Board to determine whether the
dependent claims now at issue were obvious in light of
Burns.
On remand, despite our holding that claim 1 was
shown to be unpatentable, the Board considered claim 1 to
be “at issue” and then apparently determined that the de-
pendent claims were not obvious because claim 1 was not
obvious over Burns and another reference, LaCelle. The
Board’s approach was inconsistent with our mandate in
Valve I and our case law on issue preclusion. Under our
precedent, the Board was required to recognize claim 1 as
unpatentable and then determine whether the dependent
claims were patentably indistinct from claim 1.
The Board also erred in failing to resolve factual dis-
putes and consider relevant evidence relating to whether a
person of ordinary skill in the art would be motivated to
combine Burns with LaCelle for the purposes of the
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 3
dependent claims. We vacate and remand the Board’s de-
cision for further proceedings consistent with this opinion.
BACKGROUND
I
Ironburg Inventions Ltd. (“Ironburg”) is the owner of
the ’688 patent for a hand-held games controller. The pa-
tent describes a games controller that “comprises addi-
tional controls . . . located on the rear of the controller . . .
in a position to be operated by the middle fingers of a user.”
’688 patent, Abstract; see also id., col. 1 l. 64–col. 2 l. 2. On
February 7, 2017, Valve petitioned for IPR of claims 1–3, 9,
10, 18–22, and 26–30 of the ’688 patent. In a final written
decision, the Board determined that claims 1, 2, 9, 10, 20,
22, 27, 28, and 30 were shown to be unpatentable as antic-
ipated by U.S. Patent Application Publication
No. 2015/0238855 (“Uy”) but that dependent claims 18, 19,
21, 26, and 29 were not shown to be unpatentable because
one of the pieces of prior art that Valve relied on—Burns1—
was not prior art. Valve I, 8 F.4th at 1368. Both Ironburg
and Valve appealed, and we decided that appeal on Au-
gust 17, 2021.
Three of our holdings from Valve I are particularly rel-
evant to the issues here. First, on Ironburg’s appeal, we
affirmed the Board’s determination that claim 1 of the
’688 patent was anticipated by Uy. Valve I, 8 F.4th
at 1379–81. Claim 1 recited a games controller with con-
trols on the back of the controller case:
1. A games controller comprising:
a case; and
1 Dave Burns, Review: Scuf Xbox 360 Controller,
https://www.xboxer360/features/review-scuf-xbox-360-con-
troller/.
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 4
a plurality of controls located on a front end
and a top of the case;
the case being shaped to be held in both
hands of a user such that the user’s thumbs
are positioned to operate controls located
on the top of the case and the user’s index
fingers are positioned to operate controls
located on the front end of the case;
wherein
the games controller further comprises at
least one first additional control located on
a back of the case in a position operable by
a middle, ring or little finger of the user,
the first additional control comprising a
first elongate member displaceable by the
user to activate a control function, wherein
the first elongate member comprises a first
surface disposed proximate an outer sur-
face of the case and the first elongate mem-
ber comprises a second surface opposing
the first surface, the second surface being
configured and arranged to be non-parallel
with a portion of the outer surface of the
back of the case to which the first elongate
member is mounted.
’688 patent, col. 9 ll. 28–48.
Second, on Valve’s appeal, we vacated the Board’s de-
termination that dependent claims 18, 19, 21, 26, and 29,
which depend from claim 1, were not shown to be unpatent-
able. Valve I, 8 F.4th at 1376. We reversed the Board’s
determination that Burns was not prior art and vacated
the Board’s determination that these dependent claims
were not shown to be unpatentable over Burns. Id.
at 1372, 1375–76, 1378.
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 5
Third, we remanded the case “for the Board to consider
Valve’s arguments that relied on [Burns] as to [dependent
claims 18, 19, 21, 26, and 29].” Id. at 1381; see also id.
at 1376, 1379.
II
On remand, Valve continued to argue, as it had in its
IPR petition, that claims 18, 19, 21, 26, and 29 of the
’688 patent were obvious over Burns and U.S. Design Pa-
tent No. Des. 419,985 (“LaCelle”).2 Burns is an online ar-
ticle describing an Xbox 360 Controller by Scuf with two
paddles on the back of the control pad. LaCelle is a design
patent titled “Game Controller,” which depicts different
views of a games controller and, in particular, curved fea-
tures on the back of the controller. The dependent claims
at issue on remand from Valve I recite:
18. The games controller of claim 1 wherein the
first elongate member is formed from material hav-
ing a thickness less than 5 mm.
19. The games controller of claim 1 wherein the
first elongate member is formed from material hav-
ing a thickness between 1 mm and 3 mm.
21. The games controller of claim 1 comprising two
of the first elongate members wherein, the two first
elongate members converge towards the front end
of the case with respect to one another.
2 Valve also argued that claim 21 was obvious over
Burns and the prior art reference Bellinghausen and that
claim 26 was obvious over Burns and the prior art refer-
ence Knight. In its final written decision, the Board deter-
mined that Valve had not shown that claims 21 and 26
were obvious over these prior art combinations. Valve does
not challenge those determinations on appeal here.
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 6
26. The games controller of claim 1 wherein the
first additional control is a paddle lever.
29. The games controller of claim 1 wherein the
first elongate member is inherently resilient and
flexible so as to be sufficiently displaceable to ac-
tive the control function.
’688 patent, col. 10 l. 65–col. 12 l. 9.
Despite our holding in Valve I that claim 1 was un-
patentable, the Board, in its scheduling order on remand,
directed the parties to address claim 1, stating:
We note that, because all the claims to be ad-
dressed on remand depend directly from claim 1,
we expect the parties to address on remand the
manner in which the combinations of Burns with
the [other prior art references] teach or suggest the
limitations recited in claim 1.
Valve Corp. v. Ironburg Inventions Ltd., IPR2017-00858,
Paper No. 77, at 3 n.3 (P.T.A.B. Nov. 10, 2021); see also
Valve Corp. v. Ironburg Inventions Ltd., IPR2017-00858,
Paper No. 87, at 5 n.8 (P.T.A.B. Jan. 26, 2023) (“Board Re-
mand Decision”) (similar). Subsequently, in its remand de-
cision (the decision that Valve now appeals), the Board
explained that “claim 1 [was] the only independent claim
at issue on remand.” Board Remand Decision at 9. It then
focused its remand decision on “Valve’s showing relating to
claim 1 for each of the combinations of Burns with one of
the Design References [(Burns, Bellinghausen, or Knight)]
as part of the challenge to dependent claims 18, 19, 21, 26,
and 29.” Id. at 13–14. It concluded that Valve failed to
demonstrate by a preponderance of evidence that the chal-
lenged dependent claims were unpatentable as obvious
over the combination of Burns and LaCelle apparently
based on its conclusion that claim 1 was not shown to be
unpatentable over the combination. The Board did not
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 7
address the specific limitations of the challenged depend-
ent claims.
Valve appeals. We have jurisdiction over the appeal
under 28 U.S.C. § 1295(a)(4)(A).
D ISCUSSION
I
A
We first consider the Board’s focus on the patentability
of claim 1 and whether this focus was inconsistent with our
mandate in Valve I.3 The mandate rule applies in admin-
istrative proceedings before the Board. See, e.g., Atlanta
Gas Light Co. v. Bennett Regul. Guards, Inc., 33 F.4th
1348, 1355 (Fed. Cir. 2022). “[I]n interpreting this court’s
mandate, both the letter and the spirit of the mandate
must be considered.” SUFI Network Servs., Inc. v. United
States, 817 F.3d 773, 779 (Fed. Cir. 2016) (quoting TecSec,
3 On remand, neither of the parties sought to apply
the mandate rule or any other rule under the law-of-the-
case doctrine based on our decision in Valve I, and the par-
ties did not press this issue in their briefing on appeal. We
requested the parties address these issues at oral argu-
ment. See ECF No. 54. It is appropriate to consider the
mandate rule sua sponte as it is directed at conserving ju-
dicial resources and preserving the integrity of our own
processes. United States v. Wallace, 573 F.3d 82, 90 n.6
(1st Cir. 2009); see also XY, LLC v. Trans Ova Genetics,
890 F.3d 1282, 1295 (Fed. Cir. 2018) (holding the court
may raise the application of issue preclusion sua sponte
where “there is no indication from the Patent Owner that
it did not have a full and fair opportunity to litigate the
validity of its patent in the parallel [proceeding]”) (citation
and quotation marks omitted).
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 8
Inc. v. Int’l Bus. Machs. Corp., 731 F.3d 1336, 1341–42
(Fed. Cir. 2013)).
Our decision in Valve I affirmed that claim 1 was un-
patentable, and the language of the opinion and mandate
from Valve I required that the Board treat the patentabil-
ity of claim 1 as no longer “at issue.” Board Remand Deci-
sion at 9. Our decision in Valve I, affirming that claim 1
was shown to be unpatentable, foreclosed consideration of
the issue of the patentability of claim 1. See Atlanta Gas
Light, 33 F.4th at 1355 (explaining unpatentability issues
decided on appeal were “locked in on remand by the man-
date rule”); Amado v. Microsoft Corp., 517 F.3d 1353, 1364
(Fed. Cir. 2008) (“[T]he mandate rule forecloses reconsider-
ation of issues implicitly or explicitly decided on appeal.”).4
The Board could only depart from our determination in
Valve I under exceptional circumstances, none of which is
argued to apply here.5 The Board could not determine that
4 See also Ormco Corp. v. Align Tech., Inc., 498 F.3d
1307, 1319–20 (Fed. Cir. 2007) (concluding that earlier de-
cision finding dependent claims invalid was the law of the
case and that broader independent claims must therefore
be invalid); Stearns v. Beckman Instruments, Inc., 737 F.2d
1565, 1568 (Fed. Cir. 1984) (explaining issue decided as a
matter of law was binding as the law of the case); Smith
Int’l, Inc. v. Hughes Tool Co., 759 F.2d 1572, 1577–79
(Fed. Cir. 1985) (noting law of the case applies to invalidity
determinations).
5 See Gould, Inc. v. United States, 67 F.3d 925, 930
(Fed. Cir. 1995) (explaining a court must adhere to a deci-
sion in a prior appeal unless “(1) the evidence in a subse-
quent trial is substantially different; (2) controlling
authority has since made a contrary decision of the law ap-
plicable to the issues; or (3) the earlier ruling was clearly
erroneous and would work a manifest injustice”). The
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 9
dependent claims 18, 19, 21, 26, and 29 were not shown to
be unpatentable because it concluded that claim 1 was not
shown to be unpatentable as obvious. As Ironburg recog-
nized, “[t]he Board’s decision with respect to claim 1 re-
solved Valve’s obviousness challenge of the dependent
claims,” but “[t]he Board did not go on to address the limi-
tations of the dependent claims at issue.” Appellee’s Br. 10;
see also id. at 34 (noting “[t]he Board never specifically ad-
dressed any dependent claim[—]beyond the automatic ef-
fect of its finding with respect to claim 1”).
B
On remand, the Board should have first considered
whether the dependent claims were patentably indistinct
from claim 1. In this respect, our issue preclusion prece-
dent is directly relevant. The mandate rule and issue pre-
clusion share the “fundamental precept of common-law
adjudication . . . that an issue once determined by a compe-
tent court is conclusive.” Arizona v. California, 460 U.S.
605, 619 (1983); see also Cowgill v. Raymark Indus., Inc.,
832 F.2d 798, 802 (3d Cir. 1987) (“When the estoppel is op-
erative in proceedings in the same case on remand, courts
frequently speak in terms of the law of the mandate . . . ra-
ther than collateral estoppel but the underlying principle
is the same.”); 3 James W. Moore et al., Moore’s Manual—
Federal Practice and Procedure § 30.30 (explaining the
mandate rule “is similar to issue preclusion”).6
Board’s statement that claim 1 was at issue on appeal and
its direction to the parties to address that claim in remand
briefing were thus erroneous.
6 The application of direct estoppel lends itself to the
same result. Direct estoppel precludes relitigation of com-
mon issues that have been resolved within a single suit.
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 10
As the Supreme Court held in B & B Hardware, Inc. v.
Hargis Industries, Inc., issue preclusion applies in the ad-
ministrative context and in particular to appeals to the
Board from the United States Patent and Trademark Of-
fice. 575 U.S. 138, 160 (2015). “It is well established that
collateral estoppel applies to IPR proceedings.” Google
LLC v. Hammond Dev. Int’l, 54 F.4th 1377, 1381 (Fed. Cir.
2022). This preclusive effect not only applies to claims ad-
judicated by the Board to be unpatentable but also to “re-
lated claims that present identical issues of patentability.”
MaxLinear, Inc. v. CF CRESPE LLC, 880 F.3d 1373, 1377
(Fed. Cir. 2018); see also Google, 54 F.4th at 1381 (“[C]ol-
lateral estoppel may apply even if the patent claims use
slightly different language to describe substantially the
same invention.”) (citation and internal quotation marks
omitted); Ohio Willow Wood Co. v. Alps S., LLC, 735 F.3d
1333, 1342 (Fed. Cir. 2013) (“Our precedent does not limit
collateral estoppel to patent claims that are identical.”). If
the unadjudicated patent claims do not “present materially
different issues that alter the question of patentability,”
they are said to be “patentably [in]distinct” from the
Cotton v. Heyman, 63 F.3d 1115, 1118 n.1 (D.C. Cir. 1995)
(“Direct estoppel, as opposed to collateral estoppel, governs
the preclusive effect of a litigated issue in a separate pro-
ceeding within a single suit.”); see also 18 C. Wright, A. Mil-
ler & E. Cooper, Federal Practice and Procedure § 4418.
Whether the estoppel is called collateral or direct, the anal-
ysis and application of issue preclusion “remains the
same.” DuChateau v. Camp, Dresser & McKee, Inc.,
713 F.3d 1298, 1303 (11th Cir. 2013) (citation and internal
quotation marks omitted); see also Taylor v. Sturgell,
553 U.S. 880, 892 n.5 (2008) (“[I]ssue preclusion encom-
passes the doctrines once known as ‘collateral estoppel’ and
‘direct estoppel.’”).
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 11
adjudicated claims, and issue preclusion applies. MaxLin-
ear, 880 F.3d at 1377–78; Ohio Willow Wood, 735 F.3d
at 1342 (“If the differences between the unadjudicated pa-
tent claims and adjudicated patent claims do not materi-
ally alter the question of invalidity, [issue preclusion]
applies.”).7
We have applied this principle to dependent claims
where independent claims have been demonstrated to be
unpatentable. For example, in MaxLinear, we affirmed
that independent method and device claims concerning a
television receiver were unpatentable and then remanded
the case for the Board to consider whether dependent
claims were patentably distinct from the independent
claims. 880 F.3d at 1377; see also Soverain Software LLC
v. Victoria’s Secret Direct Brand Mgmt., LLC, 778 F.3d
1311, 1319–20 (Fed. Cir. 2015) (concluding “routine incor-
poration of Internet technology into existing processes” did
not “materially alter the question of [in]validity” of a de-
pendent claim from a previously invalidated independent
claim). We have also applied the patentably distinct prin-
ciple in a similar posture as here where a case was re-
manded and returned on appeal. See Ormco Corp.,
498 F.3d at 1319–20 (affirming the district court’s determi-
nation that certain dependent claims of a patent were
7 See also Westwood Chem., Inc. v. United States,
525 F.2d 1367, 1375 (Ct. Cl. 1975) (“[T]he inquiry should
be whether the nonlitigated claims present new issues as
to the art pertinent to the nonlitigated claims; as to the
scope and content of that art; as to the differences between
the prior art and the nonlitigated claims; and as to the level
of ordinary skill in that art.”); Bourns, Inc. v. United States,
537 F.2d 486, 494 (Ct. Cl. 1976) (per curiam) (“[T]he prac-
ticalities are to look to the distinguishing features incorpo-
rated into the claims and the validity determination
necessarily focuses on those features.”).
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 12
invalid as obvious because the difference between those
claims and the invalidated claims of a related patent “was
not patentably significant”).
Accordingly, we remand for the Board to address
whether Valve has shown that the challenged dependent
claims are patentably distinct from claim 1.
II
If this case is not resolved on the grounds of collateral
estoppel, the Board must separately address the patenta-
bility of dependent claims 18, 19, 21, 26, and 29. Under
this analysis, we conclude that the Board’s decision deter-
mining that there was a lack of motivation to combine
Burns and LaCelle was not supported by substantial evi-
dence.
Obviousness is a question of law based on underlying
findings of fact. Uber Techs., Inc. v. X One, Inc., 957 F.3d
1334, 1337 (Fed. Cir. 2020). We review the Board’s factual
findings for substantial evidence and review its legal con-
clusions de novo. Id.
In its IPR petition, Valve argued that a person of ordi-
nary skill in the art would be motivated to combine Burns
and LaCelle for the following reasons:
(1) both references disclose hand-held game[s]
controllers having front controls operated by a
user’s thumbs and rear controls operated by
fingers other than the thumb, (2) the LaCelle
reference advantageously suggests an alterna-
tive rear control geometry for Burns, e.g. to give
the distal ends of the back paddles of Burns the
curved (i.e. “non-parallel”) outer shape of the
back buttons of LaCelle, and (3) changing the
outer shape of the distal ends of the Burns’
elongate members (e.g. to have the curved
outer shape of the back buttons of LaCelle)
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 13
would have been expected to be readily practi-
cal and successful in this simple and predicta-
ble art, and the results would not have been
unexpected.
J.A. 79 (citation omitted). In the context of independent
claim 1, Valve thus relied on LaCelle as showing the struc-
ture of a curved back control and that a person of ordinary
skill in the art would be motivated by this factor to combine
Burns with LaCelle.
The Board recognized that the technology is simple and
straightforward and that the level of skill required was rel-
atively low and did not require a college education. See
Board Remand Decision at 12–13. There was also no dis-
pute that, as set forth in Valve’s petition, Burns and
LaCelle disclose similar controllers because they both dis-
close hand-held games controllers with controls in similar
positions at least on the top and front part of the games
controller case and that these controls would be operated
by the same fingers. There was also no dispute that Burns,
as shown in the figure below, discloses additional controls
on the back of the games controller in a position operable
by the user’s unused middle fingers:
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 14
J.A. 83 (Burns Games Controller with Valve’s annota-
tions); see also J.A. 1261.
Nonetheless, the Board determined that Valve’s peti-
tion evidence on the motivation to combine was conclusory
and did not provide “sufficient reasoning or objective evi-
dence to demonstrate a reasonable likelihood of establish-
ing that an ordinarily skilled artisan would have found it
obvious to combine the elements from the prior art to arrive
at the claimed controllers.” Board Remand Decision
at 17–18; see also id. at 14–15.
The problem is that the Board did not address three
factual issues that also bear on the motivation to combine
Burns and LaCelle. First, in its Remand Decision, it did
not resolve whether LaCelle discloses controls on the back
of the games controller similar to Burns such that a person
of ordinary skill in the art would be motivated to combine
the two references. Supported by the testimony of its ex-
pert Dr. Rempel, Valve urged that certain “features” on the
back of the LaCelle games controller were controls:
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 15
J.A. 82 (LaCelle games controller with Valve’s annota-
tions); see also J.A. 1272; J.A. 1295 ¶¶ 27–30. Ironburg’s
expert, Dr. Stevick, disagreed, testifying that these fea-
tures were not necessarily controls, opining that these fea-
tures or components “could represent (1) surface contours,
(2) cushioned or rubberized surfaces for improved user
comfort, (3) compartments for batteries, or (4) decorative
features to conceal assembly junctions.”8 J.A. 3424–25
¶¶ 28–29. In his declaration in support of Valve’s supple-
mental reply, Dr. Rempel testified, in reference to the fea-
tures on the back of the LaCelle games controller and Dr.
Stevick’s testimony, that while the rubberized surfaces
“could be recognized as a possibility,” the other alternatives
were “unlikely based on the appearance of the drawing fea-
tures” and at any rate, the features “would primarily and
certainly suggest functional controls” based on “their loca-
tion and appearance.” J.A. 1517 ¶ 12.
Second, and even more significantly, the Board failed
to recognize the evidence that LaCelle teaches that fea-
tures on the back of the games controller are curved. Valve
argued that LaCelle “advantageously suggests an alterna-
tive rear control geometry for Burns, e.g. to give the distal
ends of the back paddles of Burns the curved (i.e., ‘non-par-
allel’) outer shape of the back buttons of LaCelle,” and fur-
ther identified that non-parallel shape in LaCelle. J.A. 79,
91; see also J.A. 1295 ¶ 27, 1296–97 ¶¶ 29–30. Before the
Board, Ironburg’s expert did not appear to dispute this
curved shape, arguing only that the features might not be
controls. See J.A. 3424–25 ¶¶ 28–29.
8 On appeal, Ironburg characterizes the features on
the back of the LaCelle controller as a “cloud of dots.” Ap-
pellee’s Br. 15, 40. The experts, however, did not testify
that these features were clouds of dots. J.A. 1295 ¶¶ 27–
30; J.A. 3425 ¶ 29.
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Third, the Board erred by declining to consider Valve’s
supplemental reply argument, supported by the testimony
of Dr. Rempel, that a person of ordinary skill would have
combined LaCelle and Burns because the skilled artisan
“would recognize that the predictable result of the combi-
nation – a back paddle having an end that is curved like
that of LaCelle – could have better coupling with the user’s
finger than the flat paddles that are otherwise disclosed by
Burns.” J.A. 1530 ¶ 39; see also J.A. 516–17. The Board
excluded that evidence as improper gap-filling that ex-
ceeded the scope of 37 C.F.R. § 42.23(b).
“The Board’s determination that a party exceeded the
scope of a proper reply [is] reviewed for abuse of discretion.”
Apple Inc. v. Andrea Elecs. Corp., 949 F.3d 697, 705
(Fed. Cir. 2020). The relevant rule, 37 C.F.R. § 42.23(b),
provides that “[a] reply may only respond to arguments
raised in the corresponding opposition, patent owner pre-
liminary response, patent owner response, or decision on
institution.” See also Axonics, Inc. v. Medtronic, Inc.,
75 F.4th 1374, 1380 (Fed. Cir. 2023). “This regulation
means that an IPR petitioner may not raise in reply an en-
tirely new rationale not raised in its petition or responsive
to arguments raised in the patent owner’s response brief.”
Yita LLC v. MacNeil IP LLC, 69 F.4th 1356, 1366 (Fed. Cir.
2023) (citations and internal quotation marks omitted).
But we have also held that reply evidence that does not of-
fer a new legal ground, but instead conforms to the theories
raised in the petition, may be properly considered in reply.
Apple, 949 F.3d at 706–7 (finding an abuse of discretion to
reject reply evidence that did not change from the legal
ground in the petition).9
9 See also Corephotonics, Ltd. v. Apple Inc., 84 F.4th
990, 1008–09 (Fed. Cir. 2023) (“‘[T]here is no blanket
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 17
Here, the petition proposed a person of ordinary skill
in the art would be motivated to combine Burns and
LaCelle because both references disclose hand-held games
controllers with similar controls that are used with the
same fingers and that LaCelle “advantageously suggests
an alternative rear control geometry for Burns, e.g. to give
the distal ends of the back paddles of Burns the curved (i.e.
‘non-parallel’) outer shape of the back buttons of LaCelle.”
J.A. 79. The supplemental reply evidence simply explained
the motivation set forth in the petition. The reply did not
offer entirely new motivations to combine or new theories
of unpatentability. Instead, the advantage it provided was
still tied to the curved, alternative geometry of the back
control supplied in the petition. It was thus error for the
Board to decline to consider the reply argument on combin-
ing the references.
The Board further determined that this evidence was
in any case insufficient as Valve’s expert only articulated
that modifying Burns in view of LaCelle “could” improve,
but not “would” improve Burns, and thus “allowe[d] that
Burns would not be improved.” Board Remand Decision
at 17. The Board, however, ignored the expert’s testimony
that a person of ordinary skill in the art “would have com-
bined LaCelle and Burns” and “would recognize that the
predictable result of the combination – a back paddle
prohibition against the introduction of new evidence dur-
ing an IPR’ provided it is an ‘expansion on and fair exten-
sion of a previously raised argument’ and has a ‘nexus’ (and
is therefore responsive) to an argument made by the patent
owner or the Board.”) (quoting Rembrandt Diagnostics, LP
v. Alere, Inc., 76 F.4th 1376, 1384–85 (Fed. Cir. 2023)
(cleaned up); Chamberlain Grp., Inc. v. One World Techs.,
Inc., 944 F.3d 919, 924–25 (Fed. Cir. 2019) (holding that
the Board erred in not considering evidence raised in oral
hearing that merely clarified party’s previous position).
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 18
having an end that is curved like that of LaCelle – could
have better coupling with the user’s finger.” J.A. 1530 ¶ 39
(second and third emphasis added); J.A. 1295 ¶ 27 (Valve’s
expert opining that “one of ordinary skill in the art in April
2014 would have been motivated to combine Burns and
LaCelle . . . .”). Moreover, “[o]bviousness does not require
absolute predictability of success.” In re O’Farrell,
853 F.2d 894, 903 (Fed. Cir. 1988). The proper inquiry is
whether a person of ordinary skill in the art would have
been motivated to combine Burns and LaCelle, not whether
the combination would with absolute certainty result in the
desired outcome. The Board thus erred in failing to con-
sider the reply evidence.
CONCLUSION
We vacate the Board Remand Decision and remand for
the Board to determine the patentability of the dependent
claims consistent with this opinion.
VACATED AND REMANDED
COSTS
No costs.
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NOTE: This disposition is nonprecedential.
United States Court of Appeals
for the Federal Circuit
______________________
VALVE CORPORATION,
Appellant
v.
IRONBURG INVENTIONS LTD.,
Appellee
______________________
2023-1725
______________________
Appeal from the United States Patent and Trademark
Office, Patent Trial and Appeal Board in No. IPR2017-
00858.
______________________
P ROST , Circuit Judge, concurring in the result.
I join Part II of the majority’s opinion beginning with
the following sentence: “Under this analysis, we conclude
that the Board’s decision determining that there was a lack
of motivation to combine Burns and LaCelle was not sup-
ported by substantial evidence.” Maj. 12. Patentability
over Burns and LaCelle was the only issue that the parties
briefed to us. And I agree with the majority’s analysis of
this issue, which suffices to resolve this appeal.
Respectfully, I cannot join Part I of the majority’s opin-
ion. The majority concludes in Part I that (1) the Board
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 2
violated our mandate in Valve I, and (2) collateral estoppel
required the Board—and requires it now—to conduct a “pa-
tentably distinct” analysis as to certain claims. I disagree
that the Board violated our mandate. And I am disinclined
to reach issues of collateral estoppel here. Those issues are
complicated, they were not briefed, and their consideration
is unnecessary to this appeal’s resolution.
As to the mandate, the majority concludes that the
Board re-evaluated claim 1’s patentability, thus violating
our mandate in Valve I, which had affirmed that claim 1
was unpatentable. See, e.g., Maj. 8 (“Our decision in
Valve I affirmed that claim 1 was unpatentable, and the
language of the opinion and mandate from Valve I required
that the Board treat the patentability of claim 1 as no
longer ‘at issue.’” (quoting Board Remand Decision, at 9));
id. at 7 (suggesting that the Board “focus[ed] on the patent-
ability of claim 1”).
I do not read the Board’s decision as having put
claim 1’s patentability at issue. Throughout its decision,
the Board repeatedly understood the issue before it to be
whether the dependent claims are patentable—not claim 1.
See Board Remand Decision, at 5 (showing a table of the
remaining claims at issue to be claims 18, 19, 21, 26, and
29 in view of Burns and another prior-art reference); id.
at 13, 19–20.
Although the Board referenced claim 1, it did so simply
because claim 1’s elements are necessarily a part of any
claims that depend from claim 1. See id. at 5 n.8, 9, 13–14.
And in an IPR, the Board must consider claims based on
the arguments drafted in the petition, including the peti-
tioner’s alleged motivation to combine prior-art references.
If those motivations are based on reasons associated with
the elements of an independent claim (or even if they just
happen to be articulated in the context of such a claim),
those motivations may still support combining the refer-
ences in the context of dependent claims. Indeed, the
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VALVE CORPORATION v. IRONBURG INVENTIONS LTD. 3
majority appears to agree that reviewing the motivations
to combine in the context of claim 1 is permissible if the
Board proceeds past the majority’s collateral-estoppel anal-
ysis. See Maj. 13 (“In the context of independent claim 1,
Valve thus relied on LaCelle as showing the structure of a
curved back control and that a person of ordinary skill in
the art would be motivated by this factor to combine Burns
with LaCelle.” (emphasis added)). Therefore, I see no error
in the Board’s references to claim 1, let alone a violation of
our mandate in Valve I.
As to collateral estoppel, I question the wisdom of in-
voking the doctrine here, where the issue was not briefed
and where its consideration is unnecessary to our resolu-
tion of this appeal (which can rest alone on Part II of the
majority’s opinion related to motivation to combine). While
I recognize collateral estoppel may, under appropriate cir-
cumstances, be raised sua sponte, I disagree this is an ap-
propriate case in which to do so. The majority’s invocation
of collateral estoppel raises a number of important ques-
tions, including which issues of “patentable distinctness”
are legal versus factual and how to resolve these issues on
a closed record (particularly in this IPR context, where the
Board is confined to addressing the arguments contained
in the petition).1 Respectfully, I would save these ques-
tions for another day.
1 To the extent the majority is suggesting merely
that petitioners and the Board should evaluate whether
claims are patentably distinct in the course of their un-
patentability analyses, I do not disagree. I assume that
this is typically done implicitly or explicitly when petition-
ers articulate their arguments with respect to dependent
claims in their petitions (and when the Board ultimately
analyzes the claims’ unpatentability in view of those argu-
ments).
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