Court Opinion

ID: 4283246
Source: CourtListenerOpinion
Date Created: 2018-06-11 15:00:48.351235+00
Date Added: 2024-06-11T14:27:02.283244
License: Public Domain

United States Court of Appeals
      for the Federal Circuit
                ______________________

                 MEDTRONIC, INC.,
                    Appellant

                           v.

                  MARK A. BARRY,
                       Appellee
                ______________________

                 2017-1169, 2017-1170
                ______________________

   Appeals from the United States Patent and Trade-
mark Office, Patent Trial and Appeal Board in Nos.
IPR2015-00780, IPR2015-00783.
                ______________________

                Decided: June 11, 2018
                ______________________

    MARK CHRISTOPHER FLEMING, Wilmer Cutler Picker-
ing Hale and Dorr LLP, Boston, MA, argued for appellant.
Also represented by ERIC FLETCHER; BRITTANY BLUEITT
AMADI, Washington, DC; RYAN NORTH MILLER, Fox Roth-
schild, LLP, Philadelphia, PA; JEFF E. SCHWARTZ, Wash-
ington, DC.

   JOHN C. ALEMANNI, Kilpatrick Townsend & Stockton
LLP, Raleigh, NC, argued for appellee. Also represented
by SEAN PAUL DEBRUINE, Law Office of Sean DeBruine,
Menlo Park, CA.
                ______________________
2                                  MEDTRONIC, INC.   v. BARRY

        Before TARANTO, PLAGER, and CHEN, Circuit Judges.
CHEN, Circuit Judge.
    This is a consolidated appeal from two related deci-
sions of the U.S. Patent and Trademark Office’s Patent
Trial and Appeals Board (Board) in inter partes review
(IPR) proceedings. The Board concluded that the peti-
tioner, Medtronic, Inc., had not proven that the chal-
lenged patent claims are unpatentable.
    We affirm-in-part and vacate-in-part. Substantial ev-
idence supports the Board’s determination that the chal-
lenged claims would not have been obvious over two
references: 1) U.S. Patent Application No. 2005/0245928
(the ’928 Application); and (2) a book chapter which
appears in Masters Techniques in Orthopaedic Surgery:
The Spine (2d ed.) (MTOS). However, we vacate the
Board’s conclusion that certain other references, i.e., a
video entitled “Thoracic Pedicle Screws for Idiopathic
Scoliosis” and slides entitled “Free Hand Thoracic Screw
Placement and Clinical Use in Scoliosis and Kyphosis
Surgery” (Video and Slides), were not prior art because
the Board did not fully consider all the factors for deter-
mining whether the Video and Slides were publicly acces-
sible. We thus remand for further proceedings. 1

    1    The Supreme Court recently held in SAS Institute
Inc. v. Iancu, 584 U.S. __ (2018), that the statute does not
permit a partial institution leading to a partial final
written decision. Because the final written decisions
relating to this appeal do not address every ground raised
in the petitions, we understand from the Board’s recent
guidance document, Guidance on the impact of SAS on
AIA       trial    proceedings      (April    26,     2018),
https://www.uspto.gov/patents-application-process/patent-
trial-and-appeal-board/trials/guidance-impact-sas-aia-
 MEDTRONIC, INC.   v. BARRY                               3

                        BACKGROUND
     Medtronic manufactures surgical systems and tools
used in spinal surgeries. In February 2014, spine surgeon
Dr. Mark Barry sued Medtronic for patent infringement
in the Eastern District of Texas. Barry alleged that
Medtronic’s products infringed a group of Barry’s patents,
including U.S. Patent Nos. 7,670,358 (the ’358 Patent)
and 7,776,072 (the ’072 Patent). Medtronic then peti-
tioned for, and the Board instituted, IPR proceedings for
all claims in both patents.
                      I. The ’358 Patent
     The ’358 Patent is directed to a method for ameliorat-
ing aberrant spinal column deviation conditions, such as
scoliosis. In addition to abnormal curvature of the spine,
scoliosis may involve the rotation of vertebrae out of
proper axial alignment. ’358 Patent col. 2, ll. 51–56. The
purported invention in the ’358 Patent spreads corrective
derotational (i.e., untwisting) forces across multiple
vertebrae, thus reducing the risk of fracture during dero-
tation. Id. at col. 3, ll. 15–25. The system includes pedi-
cle screws implanted in the pedicle regions of vertebrae to
which a surgeon, using a derotation tool, applies dero-
tational forces. As a result, “the spinal column is manipu-
lated en mass to achieve an over-all correction.” Id. at
col. 3, ll. 37–42.
    Figure 1 of the ’358 Patent shows a “pedicle screw
cluster derotation tool” engaged with a spinal column:

trial, that it will consider the previously non-considered
grounds on remand.
4                                   MEDTRONIC, INC.   v. BARRY

    As depicted in Figure 1, each pedicle screw cluster
derotation tool (30) comprises a grouping of pedicle screw
wrenches (32) connected by a linking member (42) to act
in unison during use by a surgeon. Id. at col. 5, ll. 1–6.
Each pedicle screw wrench (32) includes a handle (34) and
a shaft (36) having a distal end (38) (“pedicle screw en-
gagement member”), which is engaged with the pedicle
screw. Id. at col. 5, ll. 12–18.
     By grasping the linked handles as a group (“handle
means”), the surgeon can apply derotational forces during
a spinal corrective procedure. Id. at col. 3, ll. 48–54. “[A]s
manipulative forces are applied to the handle
means . . . [such] forces are transferred and dispersed
simultaneously among the engaged vertebrae.” Id. at
col. 3, ll. 56–59.
 MEDTRONIC, INC.   v. BARRY                            5

    Claim 1 of the ’358 Patent is representative of the
challenged claims for purposes of this appeal:
   1. A method for aligning vertebrae in the amelio-
   ration of aberrant spinal column deviation condi-
   tions comprising the steps of:
       selecting a first set of pedicle screws, said
       pedicle screws each having a threaded
       shank segment and a head segment;
       selecting a first pedicle screw cluster dero-
       tation tool, said first pedicle screw cluster
       derotation tool having first handle means
       and a first group of pedicle screw engage-
       ment members which are mechanically
       linked with said first handle means, each
       pedicle screw engagement member being
       configured for engaging with, and trans-
       mitting manipulative forces applied to
       said first handle means to said head seg-
       ment of each pedicle screw of said first set
       of pedicle screws,
       implanting a each [sic] pedicle screw in a
       pedicle region of each of a first group of
       multiple vertebrae of a spinal column
       which exhibits an aberrant spinal column
       deviation condition;
       engaging each pedicle screw engagement
       member respectively with said head seg-
       ment of each pedicle screw of said first set
       of pedicle screws; and
       applying manipulative force to said first
       handle means in a manner for simultane-
       ously engaging said first group of pedicle
       screw engagement members and first set of
       pedicle screws and thereby in a single mo-
       tion simultaneously rotating said vertebrae
6                                  MEDTRONIC, INC.   v. BARRY

       of said first group of multiple vertebrae in
       which said pedicle screws are implanted to
       achieve an amelioration of an aberrant
       spinal column deviation condition;
       selecting a first length of a spinal rod
       member; wherein one or more of said pedi-
       cle screws of said first set of pedicle screws
       each includes:
           a spinal rod conduit formed sub-
           stantially transverse of the length
           of said pedicle screw and sized and
           shaped for receiving passage of
           said     spinal     rod    member
           therethrough; and
           spinal rod engagement means for
           securing said pedicle screw and
           said spinal rod member, when ex-
           tending through said spinal rod
           conduit, in a substantially fixed
           relative position and orientation;
       extending said first length of said spinal
       rod member through said spinal rod con-
       duits of one or more of said pedicle screws
       of said first set of pedicle screws; and
       after applying said manipulative force to
       said first handle means, actuating said
       spinal rod engagement means to secure
       said vertebrae in their respective and rela-
       tive positions and orientations as achieved
       through application of said manipulative
       force thereto.
’358 Patent, claim 1 (emphasis added). The issues raised
in Medtronic’s appeal concern the italicized language of
claim 1 set out above. We will refer to the language as
the “Simultaneously Rotating” limitation.
 MEDTRONIC, INC.   v. BARRY                               7

                     II. The ’072 Patent
    The ’072 Patent is a continuation-in-part of the appli-
cation that led to the ’358 Patent and shares substantially
the same specification.
    Claim 1 of the ’072 Patent is representative of the
challenged claims of this patent, and, like Claim 1 of the
’358 Patent, recites a derotation tool that engages with
pedicle screws:
   1. A system for aligning vertebrae in the amelio-
   ration of aberrant spinal column deviation condi-
   tions comprising:
       a first set of pedicle screw, each pedicle
       screw having a threaded shank segment
       and a head segment; and
       a first pedicle screw cluster derotation tool,
       said first pedicle screw cluster derotation
       tool having a first handle means for facili-
       tating simultaneous application of manip-
       ulative forces to said first set of pedicle
       screws and a first group of three or more
       pedicle screw engagement members which
       are mechanically linked with said first
       handle means, said first handle means
       configured to move simultaneously each
       pedicle screw engagement member;
       wherein each pedicle screw engagement
       member is configured to engage respec-
       tively with said head segment of each ped-
       icle screw of said first set of pedicle
       screws; and wherein each pedicle screw
       engagement member is configured to
       transmit manipulative forces applied to
       said first handle means to said head seg-
       ment of each pedicle screw of said first set
       of pedicle screws.
8                                   MEDTRONIC, INC.   v. BARRY

’072 Patent, claim 1 (emphasis added). We will refer to
the italicized claim language as the “Derotation Tool”
limitation.
                   III. Relevant Prior Art
    Medtronic submitted the following prior art references
relevant to the issues raised in this appeal: (1) the ’928
Application; (2) MTOS; and (3) Video and Slides.
                    A. ’928 Application
     The ’928 Application is common to all of Medtronic’s
asserted grounds of obviousness that we consider on
appeal. J.A. 1789–1805. The ’928 Application discloses a
tool (“the ’928 device”) for displacing vertebrae, relative to
each other, during spinal surgery. J.A. 1789 at Abstract,
J.A. 1798 at ¶ 8. “Displacement” in the ’928 Application
refers to the movement of two vertebrae either closer
together (compression) or farther apart (distraction). The
’928 Application discloses how a surgeon makes small
incisions in the skin that are just large enough to insert
the portions of the ’928 device that engage pedicle screws
implanted in the vertebrae. J.A. 1801–02 at ¶ 46. The
skin remains intact between these incisions, allowing the
procedure to remain minimally invasive. J.A. 1799 at
¶ 24. Unlike the ’358 or the ’072 Patents, the surgical
technique described in the ’928 Application does not
involve a large incision between the vertebrae that expos-
es substantial portions of the spine. See id.; J.A. 1798 at
¶ 6.
                          B. MTOS
    MTOS is a book chapter describing techniques of us-
ing pedicle screws in the thoracic and lumbar spine. J.A.
2546–61. In one technique taught in MTOS, a surgeon
places “correcting posts” on pedicle screws on both the
convex and concave sides of the spinal curve and uses
these posts to apply manipulative force in a spinal dero-
tation procedure. J.A. 2557. MTOS describes performing
 MEDTRONIC, INC.   v. BARRY                                 9

multiple “apical vertebral derotation” (AVD) maneuvers
to derotate the spine but does not explicitly disclose
manipulating multiple posts simultaneously as part of the
AVD maneuvers. J.A. 2557–60.
                   C. The Video and Slides
    Medtronic distributed a video demonstration and a re-
lated slide presentation to spinal surgeons at various
industry meetings and conferences in 2003. J.A. 1719–57.
These video and slide sets depict derotation surgeries that
use pedicle screws and other instrumentation to correct
scoliosis. J.A. 1467–72. The Video consists of a narrated
derotation surgery performed in 2001 by Dr. Lenke, who
testified as Medtronic’s expert in this case. J.A. 1467–70.
The Slides include information about the use of pedicle
screws in derotation surgeries, including numerous pic-
tures from surgeries performed and x-rays of pre-
operative and post-operative spines. J.A. 1735–49. The
Board found that the Video and Slides, although present-
ed at three different meetings in 2003, were not publicly
accessible and therefore were not “printed publications,”
in accordance with 35 U.S.C. § 102. 2 As a result, the
Board, in its final decisions, refused to consider these
materials as prior art in its evaluation of the ’358 and ’072
Patents.
                         DISCUSSION
    We review the Board’s legal conclusions de novo and
its factual findings for substantial evidence. Ethicon
Endo-Surgery, Inc. v. Covidien LP, 812 F.3d 1023, 1028
(Fed. Cir. 2016). Substantial evidence is “such relevant
evidence as a reasonable mind might accept as adequate
to support a conclusion.” In re Applied Materials, Inc.,

    2   Because the claims at issue in this case have ef-
fective filing dates before March 16, 2013, we apply the
pre-AIA § 102.
10                                 MEDTRONIC, INC.   v. BARRY

692 F.3d 1289, 1294 (Fed. Cir. 2012) (quoting Consol.
Edison Co. of N.Y. v. NLRB, 305 U.S. 197, 229 (1938)).
We have jurisdiction over these appeals under
28 U.S.C. § 1295(a)(4) (2012).
              I. The ’358 Patent—Obviousness
     For the ’358 Patent, the Board instituted inter partes
review of claims 1–5. Method Claim 1 is the sole inde-
pendent claim, and the primary focus of the parties’
contentions concerns whether the prior art discloses claim
1’s “Simultaneously Rotating” limitation:
     applying manipulative force to said first handle
     means in a manner for simultaneously engaging
     said first group of pedicle screw engagement
     members and first set of pedicle screws and there-
     by in a single motion simultaneously rotating said
     vertebrae of said first group of multiple vertebrae
     in which said pedicle screws are implanted to
     achieve an amelioration of an aberrant spinal col-
     umn deviation condition;
’358 Patent, claim 1 (emphasis added). As explained
below, substantial evidence supports the Board’s findings
underlying its conclusion that Medtronic failed to prove
that the challenged claims would have been obvious over
the combination of the ’928 Application and MTOS.
         A. Obviousness over the ’928 Application
    Medtronic first argues that the ’928 Application alone
made it obvious for a spine surgeon to use its displace-
ment device to rotate multiple vertebrae simultaneously.
The Board, however, found that the ’928 Application fails
to disclose the “Simultaneously Rotating” limitation
because the operation of the ’928 device requires multiple
motions, as opposed to a single motion, and results in
compression or distraction of the vertebrae, as opposed to
derotation. J.A. 20. The specification of the ’928 Applica-
 MEDTRONIC, INC.   v. BARRY                              11

tion supports the Board’s finding that this claimed step is
missing from the reference.
    Figure 11 depicts a preferred embodiment of the ’928
device:

    As noted, small incisions in the skin are made above
each individual vertebra to insert guide tubes that engage
with the pedicle screws. As seen in Figure 11, when knob
112b is turned, cross action members 106b and 107b
move, causing guide tube 102b to be displaced relative to
guide tube 104, which remains stationary. Adjusting
knob 112a causes the same action regarding guide tubes
102a and 104. As the Board observed, the designed use in
12                                 MEDTRONIC, INC.   v. BARRY

the ’928 Application thus requires multiple motions to
apply force to more than one guide tube relative to anoth-
er. J.A. 20. Those motions result in compression and
distraction of vertebrae, i.e., drawing the vertebrae closer
together or farther apart along the axis of the spine. Id.
In contrast, all of the challenged claims require a handle
means to apply “simultaneous” force to a first set of
pedicle screws to rotate the vertebrae. Therefore, sub-
stantial evidence supports the Board’s finding that the
’928 Application alone does not disclose the “Simultane-
ously Rotating” limitation.
    Medtronic argues that the ’358 Patent claims never-
theless would have been obvious in light of the ’928 Appli-
cation because, once the ’928 device’s guide tubes are
inserted through the patient’s skin and engaged with the
pedicle screws, a surgeon could simply grab the device
with one hand and push or pull it—just as one may push
or pull a doorknob, in addition to turning it. Citing para-
graph 55 of the ’928 Application, Medtronic points out
that the ’928 Application discloses an embodiment that
involves applying perpendicular force to the instrument.
Medtronic also cites the testimony of its expert, Dr. Len-
ke, to explain that, “[i]f a surgeon was to use the tool
disclosed in the ’928 Application to apply this perpendicu-
lar force in a downward direction, it would naturally
cause a derotation of the vertebrae.” J.A. 1476.
     The Board observed that paragraph 55 of the ’928 Ap-
plication does not mention pulling, pushing, or twisting
the ’928 device. J.A. 29. It found that paragraph 55
“appears to disclose pressing downward or upward from
the posterior of the patient and then applying distraction
by turning the knobs of the tool.” Id. The Board, howev-
er, rejected Dr. Lenke’s opinion that the application of the
perpendicular force would necessarily result in a rotation
of the vertebrae. J.A. 30. Rather, it credited the testimo-
ny of Barry’s expert, Dr. Yassir, who opined that any
amount of rotation would be minimal and that using the
 MEDTRONIC, INC.   v. BARRY                               13

’928 device to rotate vertebrae as claimed would likely
introduce, rather than correct, spinal deformities. Id.
After considering all the evidence, the Board concluded
that, although the ’928 Application extensively discusses
compression and distraction, it says nothing about seek-
ing to rotate vertebrae—much less mention derotating
vertebrae through simultaneous application of force. Id.
    We discern no error in the Board’s determination.
There is no disclosure in the ’928 Application of scoliosis,
scoliotic curvature, or twisting of the spine. J.A. 28. Nor
is there any mentioning of derotating the spine or any
bone structure. The embodiments of the ’928 Application
instead describe “a device that may perform compression
and distraction interchangeably without the need for
having separate compression and distraction devices.”
J.A. 1798 ¶ 8. The Board reasonably found no persuasive
evidence that the ’928 Application teaches a derotational
use for its compression/distraction device or that it would
have been obvious to use such a device to “in a single
motion simultaneously rotat[e]” multiple vertebrae “to
achieve an amelioration of an aberrant spinal column
deviation condition,” as required by the claims of the ’358
Patent. J.A. 30–31.
B. Obviousness over the Combination of the ’928 Applica-
                    tion and MTOS
    Alternatively, Medtronic argues that MTOS discloses
the “Simultaneously Rotating” limitation and that one of
ordinary skill in the art would have been motivated to
combine the teachings of the ’928 Application with MTOS.
Specifically, Medtronic argues that MTOS discloses the
application of manipulative forces to a group of correcting
posts that are grasped by the surgeon in a manner for
simultaneously engaging a first group of pedicle screws.
The Board, however, rejected this characterization and
pointed out that Medtronic and its expert failed to cite to
any particular passage or figures from MTOS that “explic-
14                                MEDTRONIC, INC.   v. BARRY

itly disclose[] the simultaneous application of manipula-
tive force.” J.A. 35. This observation is consistent with
MTOS’s disclosure. J.A. 2557–60.
    Further, the Board identified significant differences
between the ’928 Application and MTOS that undercut
Medtronic’s arguments that the references were readily
combinable by the skilled artisan. J.A. 37–38. For exam-
ple, the ’928 Application discloses a “displacement de-
vice . . . that minimizes the incision made on a patient in
order to perform displacement (compression and/or dis-
traction) of bony structures.” J.A. 1798 ¶ 8. In contrast,
MTOS teaches “open” surgical procedures requiring an
invasively-large incision in the skin along the length of
the spinal column. J.A. 2557–60.
    The Board also reasonably found that neither refer-
ence discloses or suggests a device or system with a
“handle means” that performs the simultaneous rotation-
al functions as recited by the challenged claims. Specifi-
cally, MTOS discloses pedicle screw engagement
members, but lacks a single “handle means,” and does not
disclose causing a simultaneous rotation of vertebrae in a
single motion. J.A. 32, 37. And the ’928 Application only
discloses a tool with linked members and knobs that are
used to achieve controlled distraction and compression of
vertebrae. J.A. 30. Substantial evidence supports the
Board’s finding that the tools in the ’928 Application and
MTOS have different uses in different contexts in that
MTOS addresses a relatively more invasive surgery than
the ’928 Application. It also supports the Board’s conclu-
sion that Medtronic had not demonstrated by a prepon-
derance of the evidence that it would have been obvious to
a person of ordinary skill to modify either the tool dis-
closed in the ’928 Application or the pedicle screw en-
gagement members disclosed in MTOS in a manner to
achieve the “Simultaneously Rotating” claim element.
 MEDTRONIC, INC.   v. BARRY                                 15

             II. The ’072 Patent—Obviousness
    In the IPR of the ’072 Patent, Medtronic largely relied
on the same prior art references it used to challenge the
claims of the ’358 Patent. The Board’s analysis of the
patentability of the ’072 Patent claims, claims 1–4, fo-
cused on the “Derotation Tool” limitation:
    a first pedicle screw cluster derotation tool, said
    first pedicle screw cluster derotation tool having a
    first handle means for facilitating simultaneous
    application of manipulative forces to said first set
    of pedicle screws and a first group of three or more
    pedicle screw engagement members which are
    mechanically linked with said first handle means,
    said first handle means configured to move simul-
    taneously each pedicle screw engagement mem-
    ber.
’072 Patent, claim 1. The Board noted that the claim
language of the ’072 Patent was very similar to that of the
’358 Patent and that the parties’ arguments were largely
the same. J.A. 59–60. It also acknowledged that the
challenged claims in the ’072 Patent did not include the
limitation “in a single motion simultaneously rotating
vertebrae.” Id. Rather, a “fundamental issue” was
whether it would have been obvious to combine the fea-
tures of the prior art to arrive at a “derotation tool” with a
handle means that facilitates, per the claims, simultane-
ous application of forces to pedicle screws mechanically
linked through engagement members. J.A. 60. After
reviewing the prior art and considering the expert testi-
mony from both parties, the Board reasonably concluded
that Medtronic had failed to demonstrate that the chal-
lenged claims are unpatentable.
    Medtronic argues that the Board improperly inter-
preted the claims of the ’072 Patent to require rotation,
and that the Board’s analysis of obviousness is therefore
flawed. We disagree. While the Board referred to the
16                                  MEDTRONIC, INC.   v. BARRY

’358 Patent, it explicitly recognized that the claim lan-
guage in the ’072 Patent is different. It then analyzed
whether Medtronic had proven that the prior art rendered
the ’072 Patent claims obvious as written and found that
Medtronic failed to do so.
     Further, Medtronic’s contention on appeal that dero-
tation has no relevance to claims 1 and 2 of the ’072
Patent is unpersuasive. Notably, the challenged claims
all require a “derotation tool.” Moreover, Medtronic itself
argued in its petition challenging the ’072 Patent that
each of the prior art references discloses a tool or surgical
procedure for performing a derotation of the vertebrae.
See J.A. 7018–21. The Board analyzed whether the prior
art disclosed rotation because that was what Medtronic
argued as a basis for the motivation to combine the refer-
ences.
    We see no error in the Board’s analysis of the cited
references or its decision to credit the testimony of the
patent owner’s expert over that of Medtronic’s expert that
the references did not disclose a derotation tool, as
claimed. For these reasons, we conclude that substantial
evidence supports the Board’s determination that a
person of ordinary skill would not have understood the
combination of the ’928 Application and MTOS to disclose
the “Derotation Tool” limitation.
     III. Whether the Board Erred in Concluding that the
      Video and Slides Were Not Accessible to the Public
    In the IPR proceedings, Medtronic challenged the
claims of the ’358 Patent and ’072 Patent, among other
grounds, on the basis that they would have been obvious
over the combination of the ’928 Application, MTOS, and
the Video and Slides. J.A. 6, 46. 3 The Board, in its final

      3 For claims 3 and 4 of the ’072 Patent, Medtronic
also relied on U.S. Patent Application No. 2005/0033291
 MEDTRONIC, INC.   v. BARRY                              17

written decisions, found that the Video and Slides were
not prior art. J.A. 13, 54. On appeal, the parties dispute
whether the Video and Slides constitute printed publica-
tions within the meaning of 35 U.S.C. § 102(b).
    A CD containing the Video was distributed at three
separate programs in 2003: (1) a meeting of the “Spinal
Deformity Study Group” (SDSG) in Scottsdale, Arizona,
on April 10–13, 2003 (the Scottsdale program); (2) the
Advanced Concepts in Spinal Deformity Surgery meeting
in Colorado Springs, Colorado, on May 18–19, 2003 (the
Colorado Springs program); and (3) the Spinal Deformity
Study Symposium meeting in St. Louis, Missouri, on
November 13–15, 2003 (the St. Louis program). J.A.
2651–52, 2667–67. Binders containing relevant portions
of the Slides were also distributed at the Colorado Springs
and St. Louis programs. J.A. 2667, 4633.
    The earliest of the three 2003 programs, the Scotts-
dale program, was limited to SDSG members. J.A. 5904–
09. Medtronic’s witness, David Poley, described SDSG as
“a gathering of experts within the field of spinal deformi-
ty.” J.A. 5904. About 20 SDSG members attended the
Scottsdale program. J.A. 2651. The other two programs
were open to other surgeons. J.A. 2668. Medtronic spon-
sored these programs as medical education courses. J.A.
2666. Approximately 20 and 55 surgeons attended the
Colorado Springs and St. Louis programs, respectively.
J.A. 2667–68, 4633.

(the ’291 Application) as a prior art reference for its
obviousness challenge. In the final written decision for
the ’072 Patent, the Board declined to consider whether
the ’928 Application, the ’291 Application, and MTOS
separately rendered obvious claims 3 and 4 after finding
that the ’291 Application was not relevant to the disputed
“Derotation Tool” limitation. J.A. 81.
18                                 MEDTRONIC, INC.   v. BARRY

     Medtronic argues that the Board committed legal er-
ror in concluding that the Video and Slides were not
sufficiently accessible to the public. According to Med-
tronic, the Board’s sole basis for this conclusion rested on
its faulty assumption that the materials were distributed
only to members of the SDSG. See J.A. 12–13. Medtronic
points out two problems with this assumption. First, it
argues that the Board improperly ignored evidence that
the Video and Slides were distributed at programs that
were not limited to SDSG members. Second, Medtronic
contends that, even if the assumption were correct, a
reference need only be accessible to the “interested public”
to satisfy the public accessibility requirement, and that,
members of the SDSG fall squarely within that category.
    According to Barry, the Board correctly found that
“members of the Spinal Deformity Study Group, who
received the Video and Slides, were experts voted into
membership by an executive board based on their qualifi-
cations and ability to conduct research.” J.A. 12. Because
the slides were only available to experts who are part of a
group limited to members only, and not those of ordinary
skill, Barry argues that the Video and Slides were not
publicly accessible to ordinarily skilled artisans.
    Whether a reference qualifies as a “printed publica-
tion” is a legal conclusion based on underlying factual
determinations. Suffolk Techs., LLC v. AOL Inc., 752
F.3d 1358, 1364 (Fed. Cir. 2014) (citation omitted). “The
‘printed publication’ provision of § 102(b) ‘was designed to
prevent withdrawal by an inventor . . . of that which was
already in the possession of the public.’” Bruckelmyer v.
Ground Heaters, Inc., 445 F.3d 1374, 1378 (Fed. Cir.
2006) (alteration in original) (quoting In re Wyer, 655 F.2d
221, 226 (C.C.P.A. 1981)); see Blue Calypso, LLC v.
Groupon, Inc., 815 F.3d 1331, 1348 (Fed. Cir. 2016) (“This
rule is grounded on the principle that once an invention is
in the public domain, it is no longer patentable by any-
one.” (internal quotation marks and citations omitted)).
 MEDTRONIC, INC.   v. BARRY                                19

Medtronic, as the patent challenger, bears the burden of
establishing that a particular document is a printed
publication. See Blue Calypso, 815 F.3d at 1350–51
(holding that petitioner failed to carry its burden of prov-
ing public accessibility of the allegedly invalidating refer-
ence).
     The determination of whether a document is a “print-
ed publication” under 35 U.S.C. § 102(b) “involves a case-
by-case inquiry into the facts and circumstances sur-
rounding the reference’s disclosure to members of the
public.” In re Klopfenstein, 380 F.3d 1345, 1350 (Fed. Cir.
2004). “Because there are many ways in which a refer-
ence may be disseminated to the interested public, ‘public
accessibility’ has been called the touchstone in determin-
ing whether a reference constitutes a ‘printed publication’
bar under 35 U.S.C. § 102(b).” Blue Calypso, 815 F.3d at
1348 (quoting In re Hall, 781 F.2d 897, 898–99 (Fed. Cir.
1986)). “A reference will be considered publicly accessible
if it was ‘disseminated or otherwise made available to the
extent that persons interested and ordinarily skilled in
the subject matter or art exercising reasonable diligence[]
can locate it.’” Id. (quoting Kyocera Wireless Corp. v. Int’l
Trade Comm’n, 545 F.3d 1340, 1350 (Fed. Cir. 2008)).
    The issue of a reference’s public accessibility often
arises in the context of references stored in libraries. In
such cases, we generally inquire whether the reference
was sufficiently indexed or cataloged. Id. Here, we
encounter a different question: whether the distribution of
certain materials to groups of people at one or more
meetings renders such materials printed publications
under § 102(b). We have stated that a printed publication
“need not be easily searchable after publication if it was
sufficiently disseminated at the time of its publication.”
Suffolk Techs., 752 F.3d at 1365 (concluding that an
electronic newsgroup post was sufficiently disseminated
where the newsgroup was populated by those of ordinary
skill in the art and “dialogue with the intended audience
20                                MEDTRONIC, INC.   v. BARRY

was the entire purpose of the newsgroup postings,” even
though the post was non-indexed and non-searchable).
The parties here do not allege that the Video and Slides
were stored somewhere for public access after the confer-
ences. Thus, the question becomes whether such materi-
als were sufficiently disseminated at the time of their
distribution at the conferences. A survey of previous
cases involving distribution of materials at meetings
provides factors relevant to this case.
    For example, in Massachusetts Institute of Technology
v. AB Fortia (MIT), a paper that was orally presented at a
conference to a group of cell culturists interested in the
subject matter was considered a “printed publication.”
774 F.2d 1104, 1109 (Fed. Cir. 1985). In that case, be-
tween 50 and 500 persons having ordinary skill in the art
were told of the existence of the paper and informed of its
contents by the oral presentation. Id. at 1109. We took
note that the document itself was disseminated without
restriction to at least six persons. Id. at 1108–09. Thus,
whether the copies were freely distributed to interested
members of the public was a key consideration in our
analysis.
    We highlighted a similar consideration concerning ex-
pectations of confidentiality as part of the public-
accessibility inquiry in Cordis Corp. v. Boston Scientific
Corp., 561 F.3d 1319 (Fed. Cir. 2009). There, the issue
pertained to whether a set of research papers distributed
by a doctor to certain colleagues and two commercial
entities rendered the documents printed publications. Id.
at 1333. We concluded that such documents were not
publicly accessible. Id. at 1333–35. As for the doctor’s
presentation of his work to his university and hospital
colleagues, we noted that the record contained clear
evidence that the academic norms gave rise to an expecta-
tion that disclosures would remain confidential. Id. at
1334. Likewise, we held that the doctor giving the re-
search papers to two companies in an attempt to commer-
 MEDTRONIC, INC.   v. BARRY                                21

cialize the technology did not make the documents acces-
sible to the public. Id. In so concluding, we emphasized
the importance of an expectation of confidentiality be-
tween the doctor and each of the two commercial entities.
Id. The mere fact that there was no legal obligation of
confidentiality was insufficient by itself to show that the
doctor’s expectation of confidentiality was unreasonable.
Id. at 1335.
    In re Klopfenstein is also instructive in its identifica-
tion of the relevant factors. 380 F.3d 1345 (Fed. Cir.
2004). The reference in dispute in that case was a printed
slide presentation that was displayed prominently for
three days at a conference to a wide variety of partici-
pants. Id. at 1350. The reference was shown with no
stated expectation that the information would not be
copied or reproduced by those viewing it. Id. But copies
were never distributed to the public and never indexed.
Id. Under such a scenario, we identified the relevant
factors to include: (1) “the length of time the display was
exhibited,” (2) “the expertise of the target audience” (to
determine how easily those who viewed the material could
retain the information), (3) “the existence (or lack thereof)
of reasonable expectations that the material displayed
would not be copied,” and (4) “the simplicity or ease with
which the material displayed could have been copied.” Id.
After reviewing these factors, we determined that the
reference was sufficiently publicly accessible to count as a
“printed publication” for the purposes of § 102(b). Id. at
1352.
    These decisions illustrate some common considera-
tions about materials that are distributed at meetings or
conferences. As relevant to this case, the size and nature
of the meetings and whether they are open to people
interested in the subject matter of the material disclosed
are important considerations. Another factor is whether
there is an expectation of confidentiality between the
distributor and the recipients of the materials. Even if
22                                  MEDTRONIC, INC.   v. BARRY

there is no formal, legal obligation of confidentiality, it
still may be relevant to determine whether any policies or
practices associated with a particular group meeting
would give rise to an expectation that disclosures would
remain confidential.
     The record does not show that the Board fully consid-
ered all of the relevant factors. As a threshold matter, the
Board did not address the potentially-critical difference
between the SDSG meeting in Arizona and the programs
in Colorado Springs and St. Louis, which were not limited
to members of the SDSG but instead were attended by at
least 75 other surgeons, collectively. J.A. 2668. Also,
Medtronic’s expert, Dr. Lenke, testified that the materials
were distributed without restrictions at the Colorado
Springs and St. Louis programs. J.A. 1467–68, 3002.
Although the Board found that disclosure to a small group
of experts in the members-only SDSG meeting was insuf-
ficient to compel a finding that the Video and Slides were
publicly available, its analysis was silent on the distribu-
tion that occurred in the two non-SDSG programs.
     Further, even if the Board were correct in its assump-
tion that Medtronic only gave the Video and Slides to the
SDSG members, it did not address whether the disclo-
sures would remain confidential. The Board found that
SDSG members were experts voted into membership by
an executive board based on their qualifications and
research, but the relatively exclusive nature of the SDSG
membership is only one factor in the public accessibility
analysis. It may be relevant, for example, to consider the
purpose of the meetings and to determine whether the
SDSG members were expected to maintain the confiden-
tiality of received materials or would be permitted to
share or even publicize the insights gained and materials
collected at the meetings. See, e.g., J.A. 4153 (stating that
the materials were distributed at the SDSG meeting
without restriction or obligation of confidentiality).
 MEDTRONIC, INC.   v. BARRY                              23

     Accordingly, whether dissemination of the Video and
Slides to a set of supremely-skilled experts in a technical
field precludes finding such materials to be printed publi-
cations warrants further development in the record. The
expertise of the target audience can be a factor in deter-
mining public accessibility. See In re Klopfenstein, 380
F.3d at 1350–51 (“The expertise of the intended audience
can help determine how easily those who viewed it could
retain the displayed material.”). But this factor alone is
not dispositive of the inquiry. Distributing materials to a
group of experts, does not, without further basis, render
those materials publicly accessible or inaccessible, simply
by virtue of the relative expertise of the recipients. The
nature of those meetings, as well as any restrictions on
public disclosures, expectations of confidentiality, or,
alternatively, expectations of sharing the information
gained, can bear important weight in the overall inquiry.
    For these reasons, we vacate the Board’s finding that
the Video and Slides are not printed publications and
remand for further proceedings consistent with this
opinion.
                        CONCLUSION
    We affirm the Board’s conclusions that the ’928 Appli-
cation and MTOS, separately or in combination, do not
render obvious the challenged claims of the ’358 and ’072
patents. But we vacate the Board’s determination that
the Video and Slides do not qualify as prior art and re-
mand for further proceedings. On remand, the Board
shall determine, consistent with this opinion, whether the
Video and Slides are publicly-accessible publications for
prior art purposes. If not, then the inquiry ends. Other-
wise, the Board will need to consider the Video and Slides
as prior art and decide whether these references, in
combination with the ’928 Application and MTOS, render
24                                  MEDTRONIC, INC.   v. BARRY

obvious claims 1–5 of the ’358 Patent and claims 1–4 of
the ’072 Patent. 4
         AFFIRMED-IN-PART, VACATED-IN-PART
                           COSTS
     Each party shall bear its own costs.

     4For claims 3 and 4 of the ’072 Patent, the Board
shall also consider the obviousness combination in view of
the ’291 Application, to the extent applicable.