  United States Court of Appeals
      for the Federal Circuit
                 ______________________

               IN RE: NUVASIVE, INC.,
                        Appellant
                 ______________________

                  2015-1672, 2015-1673
                 ______________________

   Appeals from the United States Patent and Trade-
mark Office, Patent Trial and Appeal Board in Nos.
IPR2013-00507, IPR2013-00508.
                ______________________

               Decided: November 9, 2016
                ______________________

    MICHAEL T. ROSATO, Wilson, Sonsini, Goodrich &
Rosati, PC, Seattle, WA, argued for appellant. Also repre-
sented by ANDREW SWANSON BROWN; RICHARD TORCZON,
Washington, DC; GRACE J. PAK, PAUL DAVID TRIPODI, II,
Los Angeles, CA.

    JOSEPH MATAL, Office of the Solicitor, United States
Patent and Trademark Office, Alexandria, VA, argued for
intervenor Michelle K. Lee. Also represented by THOMAS
W. KRAUSE, SCOTT WEIDENFELLER.
                ______________________

 Before MOORE, WALLACH, and TARANTO, Circuit Judges.
TARANTO, Circuit Judge.
    NuVasive, Inc. owns U.S. Patent No. 8,187,334, which
describes and claims implants for spinal fusion surgery.
2                                      IN RE: NUVASIVE, INC.




Medtronic, Inc.—which settled with NuVasive and has
withdrawn from the present appeals—filed two petitions
for inter partes review with the Patent and Trademark
Office, which the Patent Trial and Appeal Board institut-
ed as IPR2013-507 (IPR507) and IPR2013-508 (IPR508).
The Board ultimately cancelled all but one of the chal-
lenged claims under 35 U.S.C. § 103, finding in one prior-
art reference, i.e., Michelson’s U.S. Patent No. 5,860,973,
a spinal fusion implant that meets two of the claim re-
quirements of the ’334 patent—having a length both
greater than 40 mm and at least 2.5 times its width.
Medtronic, Inc. v. NuVasive, Inc., IPR2013-507, 2015 WL
996353 (PTAB Feb. 11, 2015) (IPR507 Board Decision);
Medtronic, Inc. v. NuVasive, Inc., IPR2013-508, 2015 WL
996354 (PTAB Feb. 11, 2015) (IPR508 Board Decision).
    On appeal, NuVasive contends that it did not receive
adequate notice of or opportunity to address that reading
of Michelson and its consequences for the overall obvious-
ness analysis. We agree in part. In IPR507, Medtronic’s
petition put NuVasive on notice that Medtronic was
relying on particular portions of Michelson to teach the
’334 patent’s claimed long-and-narrow implants. In that
proceeding, we see neither procedural nor other error in
the Board’s decision, and we therefore affirm. In IPR508,
however, Medtronic’s petition did not notify NuVasive of
the assertions about the pertinent portions of Michelson
that later became critical. In that proceeding, we con-
clude, the Board’s ultimate reliance on that material,
together with its refusal to allow NuVasive to respond
fully once that material was called out, violated NuVa-
sive’s rights under the Administrative Procedure Act.
Our affirmance in IPR507 resolves the unpatentability of
the ’334 patent’s claims 1–5, 10, 11, 14, 15, and 19–28, but
claims 16 and 17 are at issue only in IPR508. We vacate
the Board’s IPR508 decision and remand for further
proceedings on claims 16 and 17.
IN RE: NUVASIVE, INC.                                       3



                              I
     The spinal fusion implant of the ’334 patent is de-
signed to be inserted between two vertebrae to replace a
damaged or diseased intervertebral disc. ’334 patent, col.
1, lines 29–36. The implant shares many features with
prior-art implants, such as anti-migration teeth to hold
the implant in place, id., col. 2, lines 40–52, vertical holes
(fusion apertures) to allow bone to grow through the
implant, id., col. 5, lines 36–40, and horizontal holes
(visualization apertures) so that a doctor can see such
bone growth, id., col. 5, lines 54–66. Although the patent
itself does not limit the methods of inserting the implant,
its long-and-thin design is particularly suited to an ap-
proach from the side, through the psoas muscle, rather
than from the front or back of the patient. Id., col. 5, lines
29–35. The focus of the obviousness issue now on appeal
is certain dimensions of the claimed implant, specifically,
a length that is both greater than 40 mm and at least 2.5
times the maximum width. The relevant part of claim 1,
the only independent claim, reads:
    1. A spinal fusion implant of non-bone construc-
    tion positionable within an interbody space be-
    tween a first vertebra and a second vertebra . . .
    wherein said implant has a longitudinal length
    greater than 40 mm extending from a proximal
    end of said proximal wall to a distal end of said
    distal wall;
    wherein a central region of said implant includes
    portions of the first and second sidewalls posi-
    tioned generally centrally between the proximal
    wall and the distal wall, at least a portion of the
    central region defining a maximum lateral width
    of said implant extending from said first sidewall
    to said second sidewall, wherein said longitu-
    dinal length is at least two and half [sic]
4                                      IN RE: NUVASIVE, INC.




    times greater than said maximum lateral
    width . . . .
’334 patent, col. 12, line 32, through col. 13, line 4 (em-
phases added).
    NuVasive asserted the ’334 patent against Medtronic
in Warsaw Orthopedic, Inc. v. NuVasive, Inc., No. 3:12-cv-
02738-CAB-MDD (S.D. Cal.). Medtronic thereafter filed
two separate petitions for inter partes review of the ’334
patent under 35 U.S.C. §§ 311–319. 1
    Medtronic’s petition in what became IPR507 relied
primarily on U.S. Patent Application Publication No.
2002/0165550 (published Nov. 7, 2002) (Frey), which
teaches an implant whose length is at least 2.5 times the
width. As relevant here, Medtronic argued that it would
have been obvious to modify Frey to have a length greater
than 40 mm, as taught by Michelson. But in one brief
passage, Medtronic’s petition went further. In pointing
out that Michelson also teaches many of the ’334 limita-
tions, Medtronic stated that “[l]ike Frey, Michelson dis-
closes example lateral fusion implants having an
elongated shape” and “dimensions that are longer than
wide,” citing Michelson, col. 10, line 6, through col. 11,
line 15. J.A. 172. That cited range includes a discussion
of Michelson’s Figure 18, which shows an “alternative
embodiment . . . 1000 . . . similar to the spinal fusion
implant 900, but [which] has a narrower width such that
more than one spinal fusion implant 1000 may be com-
bined in a modular fashion for insertion within the disc
space D between the adjacent vertebrae.” Michelson, col.
10, lines 48–55.



    1   Medtronic separately sought review of NuVasive’s
U.S. Patent No. 8,361,156. The Board decision in that
review, IPR2013-506, is before this court in In re NuVa-
sive, No. 2015-1670.
IN RE: NUVASIVE, INC.                                   5



    Medtronic’s petition in what became IPR508 relied
primarily on the Synthes Vertebral Spacer-PR Brochure,
Synthes Spine 2002 (SVS-PR), and the Telamon Verte-
Stack PEEK Vertebral Body Spacer Brochure and the
accompanying Telamon Posterior Impacted Fusion Devic-
es Guide 2003 (jointly, Telamon), which teach implants
whose lengths are at least 2.5 times their widths. Med-
tronic argued that it would have been obvious to modify
either SVS-PR or Telamon to have lengths greater than
40 mm, as taught by Michelson.         But in the SVS-
PR/Telamon petition, unlike the Frey petition, Medtronic
did not include an assertion about or citation to material
encompassing Michelson’s Figure 18.
    In response to Medtronic’s petitions, the Board, exer-
cising institution authority delegated by the PTO Direc-
tor, 37 C.F.R. §§ 42.4, 42.108, determined that there was
a reasonable likelihood that Medtronic would establish,
by a preponderance of the evidence, that claims 1–5, 10,
11, 14, 15, and 18–28 would have been obvious over Frey,
in view of Michelson. On that basis, the Board instituted
IPR507. The Board made comparable determinations as
to claims 1–5, 10, 11, and 14–28 based on either SVS-PR
or Telamon, in view of Michelson and U.S. Patent Appli-
cation Publication No. 2003/0028249 (published Feb. 6,
2003) (Baccelli). On that basis, the Board instituted
IPR508. The two proceedings involve all the same claims
apart from claims 16 and 17, which are the subject of
IPR508, but not IPR507.
    When NuVasive filed its Patent Owner Responses, it
argued that no single reference taught an implant that
was both longer than 40 mm and had a length at least 2.5
times its width. NuVasive pointed to Michelson’s Figures
16 (showing long-and-wide rectangular implant 900), 19
(showing a plurality of “narrower” implants 1000 lined up
in the disc space), and 20 (showing another long-and-wide
rectangular implant), as evidence that a person of ordi-
nary skill reading Michelson would size an implant to be
6                                       IN RE: NUVASIVE, INC.




both long and wide (not long and narrow) in order to
maximize the surface area of contact with the vertebrae,
as taught by Michelson. NuVasive further argued that
there was no reason for a person of skill in the art to
combine the length of Michelson with the length-to-width
ratio of the primary references, because doing so would
make the resulting implant an unsuitable size for the
intended insertion path of the primary references, which
NuVasive contends were inserted from the front or back,
not the side.
    In its replies, Medtronic pointed to Michelson’s Fig-
ure 18 specifically and argued that it disclosed an implant
whose length was greater than 40 mm and at least 2.5
times its width.
    NuVasive objected to Medtronic’s argument regarding
Michelson’s Figure 18, which it contended was a new
ground of invalidity asserted for the first time on reply. It
requested leave to file motions to strike or, alternatively,
surreplies, which the Board denied. NuVasive also at-
tempted to address the matter at oral argument, but the
Board refused to allow NuVasive to make substantive
arguments in response. When Medtronic made argu-
ments relating to Michelson’s Figure 18 in its rebuttal
time, NuVasive objected again, but the Board assured
NuVasive that it understood NuVasive’s position and
would consider the propriety of Medtronic’s arguments
when making a final decision.
    The Board ultimately held, in IPR507, that claims 1–
5, 10, 11, 14, 15, and 19–28 would have been obvious over
Frey and Michelson, but it upheld claim 18. In IPR508,
the Board held that claims 1–5, 10, 11, 14–17, and 19–28
would have been obvious over either SVS-PR or Telamon
in view of Baccelli and Michelson, but it upheld claim 18.
    The Board’s decisions relied heavily on its findings
that Michelson, by itself, discloses both disputed dimen-
sional limitations in a single implant—one whose length
IN RE: NUVASIVE, INC.                                     7



is both greater than 40 mm and at least 2.5 times its
width—so that no combining of references was needed to
arrive at an implant that meets both requirements. Thus,
in IPR507, the Board never found that Frey teaches an
implant with a length at least 2.5 times the width. Ra-
ther, it found that if one combined (1) Michelson’s teach-
ing that the preferred overall width of the implant was
26 mm with (2) Michelson’s teaching that at least two
“narrower” implants could be combined to fit that space,
then at least one of the “narrower” implants would be at
most 13 mm wide, which is less than the preferred length
(42 mm) divided by 2.5. IPR507 Board Decision at *5. On
that basis, the Board concluded that “it would have been
obvious to one of ordinary skill in the art to have provided
an implant with a length of greater than 40 mm (e.g.,
42 mm) and at least 2.5 times the width.” Id. at *6.
    Similarly, in IPR508, the Board did not find that SVS-
PR or Telamon discloses an implant whose length is at
least 2.5 times its width. Rather it “credit[ed] the testi-
mony [submitted along with Medtronic’s reply] of Peti-
tioner’s Declarant (Dr. Richard A. Hynes) that Michelson
discloses a spinal implant with a length that is greater
than 40mm and at least 2.5 times the width,” made the
same calculations it made in IPR507, and came to the
same conclusion verbatim. IPR508 Board Decision at *4.
    NuVasive appeals. Medtronic had cross-appealed
from the Board’s decisions regarding claim 18, but Med-
tronic later withdrew, and we dismissed, the cross-
appeals (Nos. 2015-1674, -1712). The Director of the PTO
intervened to defend the Board’s rulings against NuVa-
sive’s inadequate-process challenges. We have jurisdic-
tion under 28 U.S.C. § 1295(a)(4)(A).
                             II
    Under the Administrative Procedure Act, we must
“hold unlawful and set aside agency action . . . not in
accordance with law [or] . . . without observance of proce-
8                                        IN RE: NUVASIVE, INC.




dure required by law.” 5 U.S.C. § 706. In the non-IPR
setting, we have made clear that whether a ground the
Board relied on was “new,” requiring a new opportunity to
respond, is a question of law, subject to de novo review.
See In re Stepan Co., 660 F.3d 1341, 1343 (Fed. Cir. 2011).
No different standard of review is called for on the closely
related issue in the IPR context. See Belden Inc. v. Berk-
Tek LLC, 805 F.3d 1064, 1080 (Fed. Cir. 2015) (noting
similarity of issues). Obviousness is a question of law
based on underlying determinations of fact. See, e.g., id.
at 1073. We review the Board’s conclusions of law de
novo and its findings of fact for substantial evidence. Id.
    We first address NuVasive’s procedural challenges to
the Board’s reliance on Michelson’s Figure 18 in the two
IPRs. We then address NuVasive’s remaining challenges.
                              A
    “A patent owner in [NuVasive’s] position is undoubt-
edly entitled to notice of and a fair opportunity to meet
the grounds of rejection,” based on due-process and APA
guarantees. Belden, 805 F.3d at 1080. “For a formal
adjudication like the inter partes review considered here,
the APA imposes particular requirements on the PTO.
The agency must ‘timely inform[]’ the patent owner of ‘the
matters of fact and law asserted,’ 5 U.S.C. § 554(b)(3),
must provide ‘all interested parties opportunity for the
submission and consideration of facts [and] arguments . . .
[and] hearing and decision on notice,’ id. § 554(c), and
must allow ‘a party . . . to submit rebuttal evidence . . . as
may be required for a full and true disclosure of the facts,’
id. § 556(d).” Dell Inc. v. Acceleron, LLC, 818 F.3d 1293,
1301 (Fed. Cir. 2016) (alterations in original). While “the
rules and practices of the Board generally protect against
loss of patent rights without the required notice and
opportunity to respond,” Belden, 805 F.3d at 1080 (em-
phasis added), those rules and practices protect against
such loss in a given case only when, upon a proper re-
IN RE: NUVASIVE, INC.                                       9



quest, the PTO actually provides the opportunities re-
quired by the APA and due process.
                              1
    Although the Board is not limited to citing only por-
tions of the prior art specifically drawn to its attention, in
this case it is clear that the Board treated Michelson’s
Figure 18 as an essential part of its obviousness findings
identifying claim elements in the prior art. It relied on
Michelson’s Figure 18 and nothing else for a prior-art
disclosure of an implant having a length that is greater
than 40 mm and at least 2.5 times its width. The Board
made no findings that another reference disclosed an
implant having both those characteristics. Nor did it find
that such dimensions would have been obvious even if not
found together in a single piece of prior art. Nor, indeed,
did the Board find a prior-art implant having a length at
least 2.5 times its width and then explain the obviousness
of a combination of that limitation with the distinct
requirement of sufficient length.
     We are in no position to treat the Board’s finding
about Michelson’s Figure 18 as immaterial given the
limited other findings so far made by the Board. Nor can
this factual finding be analogized to others that merely
reinforce the meaning of another prior-art disclosure.
Thus, the Figure 18 finding did not “merely serve[ ] to
describe the state of the art [at the time of the invention],”
informing the understanding of another, separate prior-
art disclosure of a claim limitation. Genzyme Therapeutic
Prods. Ltd. v. Biomarin Pharm. Inc., 825 F.3d 1360,
1368–69 (Fed. Cir. 2016) (finding that the Board did not
violate the APA by citing references not part of the com-
binations set forth in the institution decisions where those
references “merely served to describe the state of the art
[at the time of invention],” and were “not among the prior
art references that the Board relied upon to establish any
claim limitations”); Belden, 805 F.3d at 1079 (noting that
10                                     IN RE: NUVASIVE, INC.




certain explanatory evidence was not “necessary to the
prima facie case”).
    Under the APA’s standards, NuVasive was entitled to
an adequate opportunity to respond to this asserted fact
about Michelson. And under the APA’s fact-specific
standard, common sense, and this court’s precedent, that
entitlement was not lessened in this case by virtue of the
opportunity NuVasive had to respond to other factual
assertions about Michelson. In Dell, we held that an
opportunity to respond was needed when the petitioner, to
make its anticipation showing, newly pointed to a previ-
ously unmentioned portion of the allegedly anticipatory
prior-art patent, even though it had earlier focused exten-
sively on other portions of that prior-art patent. 818 F.3d
at 1301. In the related, non-IPR context, we have relied
on the APA’s requirements to find a “new ground” where
“the thrust of the rejection” has changed, even when the
new ground involved the same prior art as earlier assert-
ed grounds of invalidity. In re Leithem, 661 F.3d 1316,
1319 (Fed. Cir. 2011). Here, the assertion about Fig-
ure 18 on which the Board ultimately relied is sufficiently
distinct from Medtronic’s other assertions about Michel-
son that NuVasive was entitled to the APA-required
opportunity to respond to it.
                            2
    In IPR507, NuVasive had that opportunity. There is
no dispute that NuVasive’s Patent Owner Response was
an adequate opportunity to respond if Medtronic’s peti-
tion put NuVasive on notice of the assertion about Fig-
ure 18. In IPR507, we conclude that the notice was at
least minimally sufficient.
    In IPR507, Medtronic’s petition cited the Michelson
text that specifically discusses Figure 18 in addition to
nearby figures in Michelson. The petition did so in assert-
ing that the text shows “longer than wide” implants. J.A.
172. The only limitation in the ’334 patent addressing a
IN RE: NUVASIVE, INC.                                   11



comparison of length to width is the one requiring length
at least 2.5 times width. It is true that Medtronic did not
make a clear or direct reference to that limitation or a
clear or direct assertion that the 2.5 ratio is shown in
Michelson, in Figure 18 or elsewhere. But we think that
the citation of the text discussing Figure 18, plus the
reference to “longer than wide” implants, should have put
NuVasive on notice that it was obliged to use its Patent
Owner Response to address Figure 18 and its relationship
to the length/width ratio claim limitation.
                            3
    IPR508 is different. In that proceeding, Medtronic did
not include in its petition the same citations to or asser-
tions about the Michelson passage that it included in the
IPR507 petition. In IPR508, unlike IPR507, there was no
notice of the Figure 18 point before NuVasive filed its
Patent Owner Response. The opportunity to file that
Response therefore did not provide the required oppor-
tunity to address the factual assertion about Figure 18 on
which the Board ultimately relied.
    Despite the consolidated hearing in the two proceed-
ings, the Board treated each inter partes review as a
separate, distinct proceeding, and it issued separate final
written decisions, independently invalidating some of the
same claims based on different mixes of prior art. The
Director has furnished no persuasive basis on which we
are prepared to hold that a (barely sufficient) notice in
one proceeding constituted an obligation-triggering notice
in the other proceeding in which a comparable notice was
missing. Nor do we see a basis for concluding that the
Board could rely on the Figure 18 point in IPR508, where
no sufficient notice was given, just because NuVasive
chose, in cut-and-paste fashion, to include highly similar
discussions of Michelson in its Patent Owner Responses
in the two proceedings. We note that neither of NuVa-
sive’s Responses addresses Figure 18, even while they do
12                                     IN RE: NUVASIVE, INC.




address some of the content of the Michelson passage
cited by Medtronic in the IPR507 petition. 2
    Not until Medtronic’s Reply, after NuVasive’s Patent
Owner Response, was NuVasive given fair notice in
IPR508 of the Figure 18 factual assertion on which the
Board eventually relied. But at no point after the Reply
did the Board give NuVasive the required opportunity to
respond to that point. Despite requests from NuVasive,
the Board refused to permit NuVasive to file a surreply or
even to address the matter during oral argument.
    The Director points out that, although NuVasive was
prohibited from filing a motion to strike or a surreply, it
was permitted to cross-examine Dr. Hynes, the relevant
expert for Medtronic, and to file “observations” on the
cross-examination. We have identified such observations
as among the vehicles available to protect against APA
violations, but we have not declared that vehicle always
sufficient to ensure the required opportunity to respond.
Belden, 805 F.3d at 1081. Here, the opportunity to file
observations was not enough. “Observations” are not a
vehicle for submitting new evidence, including new expert
declarations, by the patent owner. Indeed, the permitted
content and format of observations are tightly circum-
scribed, see Office Patent Trial Practice Guide, 77 Fed.


     2  What NuVasive said in its Responses was enough
to allow the Board to conclude that Medtronic’s Reply
assertions about Figure 18 came within the rule that “[a]
reply may only respond to arguments raised in the corre-
sponding opposition, patent owner preliminary response,
or patent owner response.” 37 C.F.R. § 42.23(b). But
satisfying that rule does not mean that the pre-Response
notice was sufficient. See In re Biedermann, 733 F.3d
329, 338 (Fed. Cir. 2013) (“A new ground of rejection is
not negated by the fact that the Board is responding to an
appellant’s argument.”).
IN RE: NUVASIVE, INC.                                  13



Reg. 48,756, 48,768 (Aug. 14, 2012), and here the Board
rejected portions of NuVasive’s observations for being too
argumentative. We cannot view “observations” as a
substitute for the opportunity to present arguments and
evidence.
                            B
                            1
    Finding no procedural violation in IPR507, we consid-
er NuVasive’s remaining arguments against the Board’s
obviousness ruling in that IPR. NuVasive contends that
the Board impermissibly relied on speculation to find that
Michelson taught an implant whose length is 2.5 times its
width and that the Board did not sufficiently find a rea-
son to combine Michelson with the primary references.
We reject those contentions.
    As to what Michelson discloses: Far from relying on
speculation, the Board had a solid basis in Medtronic’s
argument and in Michelson itself for finding that Fig-
ure 18 disclosed an implant having both the length and
width characteristics at issue. The Board “base[d] its
decision on arguments that were advanced by a party,” In
re Magnum Oil Tools Int’l, Ltd., 829 F.3d 1364, 1381 (Fed.
Cir. 2016), and, “[i]n the circumstances here,” could
permissibly “rely on its own reading of [Michelson]—
supported by the Petition’s observations about it”—to find
that the claim-required implant characteristics were
disclosed, Belden, 805 F.3d at 1074.
    Medtronic pointed the Board to Figure 18 and the cor-
responding description as supporting the proposition that
Michelson disclosed longer-than-wide implants. Michel-
son’s specification expressly states that the preferred
length of embodiment 900 was 42 mm and the preferred
width was 26 mm. Michelson, col. 10, lines 42–47. It
then states that “spinal fusion implant 1000 is similar to
the spinal fusion implant 900, but has a narrower width
14                                     IN RE: NUVASIVE, INC.




such that more than one spinal fusion implant 1000 may
be combined in a modular fashion for insertion within the
disc space.” Id., col. 10, lines 50–55. Figure 18 shows
implant 1000, and Figure 19 shows three implant 1000s
lined up in the disk space. Id., Figures 18 & 19. Even if
Figure 19 were taken as showing only two implants (its
point is to show more than one), this is substantial, and
anything but speculative, evidence from which to infer
that at least one of the set of “narrower” implants must be
at most 13 mm wide (at its maximum), which is less than
the preferred length (42 mm) divided by 2.5 (16.8 mm).
    As to reasons to combine: The Board did not have to
find a reason that a relevant artisan would combine the
length of an implant from one prior-art reference with the
length-to-width ratio of an implant from another refer-
ence, because it found that Michelson disclosed an im-
plant meeting both limitations. Although the Board did
not make findings as to whether any of the other claim
limitations (such as fusion apertures or anti-migration
teeth) are disclosed in the prior art, it did not have to:
NuVasive did not present arguments about those limita-
tions to the Board.
     NuVasive’s arguments before the Board focused only
on the dimensions of the implant—(1) that it would not
have been obvious to modify Frey to have a length greater
than 40 mm because it would make Frey unsuitable for
its intended path of insertion, (2) that it would not have
been obvious to lengthen Frey to be longer than the intra-
annulus region in which Frey was intended to sit, and
(3) that if a skilled artisan had undertaken to modify Frey
according to Michelson, the resulting implant would have
been long and wide (not long and narrow) because Michel-
son stresses the importance of maximizing surface-area
contact with the vertebrae. Substantial evidence supports
the Board’s specific findings that (1) “a spinal implant
measuring up to 45 mm in length” would not render Frey
“inoperable” for its intended purpose, even if Frey were
IN RE: NUVASIVE, INC.                                  15



limited to use in transforaminal lumbar interbody fusion
(TLIF) procedures, IPR507 Board Decision at *4; (2) an
implant could be longer than 40 mm and not violate the
teaching of Frey that it fit within the inner-annulus
region, id. at *4–5; and (3) Michelson in fact teaches the
relevant long-and-narrow implants, id. at *5. This was
sufficient to make an affirmative, supported case for the
obviousness of the challenged ’334 claims, given the
limited arguments presented by NuVasive. The Board,
having found the only disputed limitations together in one
reference, was not required to address undisputed mat-
ters.
     In particular, NuVasive argues on appeal (1) that a
skilled artisan would never have made a long-and-narrow
implant for any use other than as a component to be
assembled into a single, oversized, modular implant; (2)
that, given the state of modular implants at the time of
the invention, no one would have tried to make one; and
(3) that the boomerang-shaped Frey implant would not
have been suitable to be modified to be modular. But
NuVasive did not present any meaningful argument to
that effect to the Board. The Board cannot be faulted for
not addressing such an argument where, as we have
determined for IPR507, NuVasive was on notice, before it
filed its Patent Owner Response, that Michelson’s Fig-
ure 18 could be used to disclose the dimensional limita-
tions of the ’334 patent and therefore was on notice that
those dimensions might be combined with other prior-art
references.
                            2
    In IPR508, we have found a procedural violation.
That finding does not support reversal of the Board’s
cancellations. Rather, it warrants a remand for further
proceedings.
   NuVasive relies on the Board’s statements finding in-
adequate Medtronic’s showings with respect to claim 18,
16                                    IN RE: NUVASIVE, INC.




which requires particular dimensions—namely, a length
greater than 40 mm and a maximum width of 18 mm. See
IPR508 Board Decision at *8; see also IPR507 Board
Decision at *6. But those statements do not entail a
failure of proof of obviousness as to claims lacking the
particular dimensional requirements of claim 18. They do
not decide more generally that it would not have been
obvious to combine “one dimension from one implant with
a second dimension from another implant.” Resp. &
Reply Br. 30–31; see id. at 39–40. Nor do they preclude
the Board from considering the import of Michelson’s
Figure 18 after giving NuVasive a full opportunity to
submit additional evidence and arguments on that point.
See In re Kumar, 418 F.3d 1361, 1367–69 (Fed. Cir. 2005).
                      CONCLUSION
    For the foregoing reasons, we affirm the Board’s final
written decision in IPR2013-507, invalidating claims 1–5,
10, 11, 14, 15, and 19–28 and upholding claim 18. We
vacate the Board’s decision in IPR2013-508 and remand
for further proceedings regarding claims 16 and 17 in
accordance with this opinion.
      No costs.
     AFFIRMED IN PART, VACATED IN PART, AND
                   REMANDED
