Medtronic, Inc. v. Barry , 891 F.3d 1368 ( 2018 )


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  •   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.