Ethicon Endo-Surgery, Inc. v. Covidien, Inc. , 796 F.3d 1312 ( 2015 )


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  •   United States Court of Appeals
    for the Federal Circuit
    ______________________
    ETHICON ENDO-SURGERY, INC.,
    ETHICON ENDO-SURGERY, LLC,
    Plaintiffs-Appellants
    v.
    COVIDIEN, INC., COVIDIEN LP,
    Defendants-Appellees
    ______________________
    2014-1370
    ______________________
    Appeal from the United States District Court for the
    Southern District of Ohio in No. 1:11-cv-00871-TSB,
    Judge Timothy S. Black.
    ______________________
    Decided: August 7, 2015
    ______________________
    WILLIAM F. CAVANAUGH, Jr., Patterson Belknap Webb
    & Tyler LLP, New York, NY, argued for plaintiffs-
    appellants. Also represented by CHAD J. PETERMAN,
    JEREMY A. WEINBERG, R. JAMES MADIGAN III, HELEN P.
    O’REILLY.
    DREW MILLER WINTRINGHAM III, DLA Piper US LLP,
    New York, NY, argued for defendants-appellees. Also
    represented by FRANCIS W. RYAN IV, MATTHEW GANAS,
    MELISSA REINCKENS; STANLEY JOSEPH PANIKOWSKI III,
    San Diego, CA.
    2              ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    ______________________
    Before LOURIE, BRYSON, and CHEN, Circuit Judges.
    CHEN, Circuit Judge.
    Plaintiffs-appellants Ethicon Endo-Surgery, Inc. and
    Ethicon Endo-Surgery, LLC (collectively, Ethicon) sued
    defendants-appellees Covidien, Inc. and Covidien LP
    (collectively, Covidien) in the U.S. District Court for the
    Southern District of Ohio for alleged infringement of
    several utility and design patents related to ultrasonic
    surgical devices. After the close of discovery, the district
    court granted Covidien’s motions for summary judgment,
    concluding that 1) 
    U.S. Patent No. 8,182,501
     (the ’501
    patent) is invalid as indefinite, 2) 
    U.S. Patent No. 5,989,275
     (the ’275 patent) is not infringed by Covidien’s
    accused products, and 3) U.S. Patent Nos. D661,801 (the
    D’801 patent), D661,802 (the D’802 patent), D661,803 (the
    D’803 patent), and D661,804 (the D’804 patent) (collec-
    tively, the Design Patents) are invalid as functional and
    in the alternative, not infringed. The district court en-
    tered final judgment in favor of Covidien, and Ethicon
    now appeals.
    We reverse and vacate in part. As to the ’501 patent,
    we reverse the district court’s grant of invalidity for
    indefiniteness, because the specification provides suffi-
    cient guidance to a person of ordinary skill in the art as to
    the scope of its asserted claims. As to the ’275 patent, we
    vacate the district court’s grant of summary judgment of
    noninfringement because the district court improperly
    resolved genuine disputes of material fact in favor of
    Covidien instead of Ethicon, the non-moving party, and
    questions of fact remain as to whether Covidien’s accused
    ultrasonic devices infringe the asserted claims of the ’275
    patent.
    As for the Design Patents, we reverse the district
    court’s grant of invalidity based on functionality. The
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.            3
    district court evaluated the claimed designs using too
    high a level of abstraction, focusing on the unclaimed
    utilitarian aspects of the underlying article instead of the
    claimed ornamental designs of that underlying article.
    We affirm, however, the district court’s grant of summary
    judgment of noninfringement of the Design Patents.
    After the functional aspects of the claimed designs are
    properly excluded from the infringement analysis, the
    claimed ornamental designs are plainly dissimilar from
    the ornamental design of Covidien’s accused products.
    Based on the foregoing, we remand to the district court to
    resolve Ethicon’s allegations that Covidien’s accused
    devices infringe the asserted claims of the ’501 and ’275
    patents.
    I. BACKGROUND
    The patents-in-suit are directed to surgical instru-
    ments that use ultrasonic energy created by blades vibrat-
    ing at high frequencies to cut tissue and blood vessels.
    These surgical instruments also use the heat generated
    from the friction of the blade vibrating against the blood
    vessel to coagulate and seal those blood vessels in order to
    prevent bleeding. Ethicon develops, manufactures, and
    sells such ultrasonic surgical instruments. After Covidien
    launched a competing line of ultrasonic surgical equip-
    ment, Ethicon sued Covidien, alleging infringement of the
    utility and design patents at issue in this appeal, among
    others. Both parties waived their rights to a jury trial
    and agreed to a bench trial on all disputed issues. After
    Markman proceedings and the close of discovery, Covidien
    successfully moved for summary judgment of invalidity
    and/or noninfringement of the asserted patent claims.
    See Ethicon Endo-Surgery, Inc. v. Covidien, Inc., No. 11-
    cv-871, ECF Nos. 130–32 (S.D. Oh. Jan 22, 2014) (Ethicon
    DCt). The district court entered a stipulated final judg-
    ment of noninfringement and/or invalidity of all patents-
    in-suit in favor of Covidien. Ethicon timely appealed, and
    4              ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    we have jurisdiction over Ethicon’s appeal pursuant to 
    28 U.S.C. § 1295
    (a)(1).
    II. DISCUSSION
    We review the grant of summary judgment under the
    law of the regional circuit. Lexion Med., LLC v. Northgate
    Techs., Inc., 
    641 F.3d 1352
    , 1358 (Fed. Cir. 2011). The
    Sixth Circuit reviews an order granting summary judg-
    ment de novo. Savage v. Gee, 
    665 F.3d 732
    , 737 (6th Cir.
    2012).
    A. The ’501 patent
    The ’501 patent is directed to ultrasonic surgical
    shears for cutting and sealing a blood vessel. ’501 patent,
    1:20–23. The claimed device includes an ultrasonic
    surgical blade, a clamping arm, and a tissue pad attached
    to the clamping arm. 
    Id.
     at 2:7–10. The clamping arm
    opens and closes towards the ultrasonic blade in a man-
    ner similar to the two blades of a pair of scissors. 
    Id.
     at
    2:8–9. During use, a blood vessel is positioned between
    the blade and the tissue pad on the clamping arm. 
    Id.
     at
    1:67–2:2. When the blade and clamping arm are in a
    “closed position,” the average clamping pressure on the
    blood vessel is between 60 and 210 pounds per square
    inch (psi). 
    Id.
     at 2:2–4. The ultrasonic blade then vi-
    brates at a high frequency. 
    Id.
     at 2:4–5. The combination
    of this ultrasonically-vibrating blade and clamping pres-
    sure on the blood vessel results in the bringing together
    the walls of the blood vessel (a “coaptation”), the cutting
    of the coaptated blood vessel (a “transection”), and the
    sealing of the coaptated cut ends of the blood vessel (a
    “coagulation”). 
    Id.
     at 1:40–46. According to the ’501
    patent, the 60 to 210 psi average clamping pressure range
    provides improved blood vessel sealing with shorter
    transection times on smaller blood vessels and blood
    vessel sealing with acceptable transection times on larger
    blood vessels, a result which was not conventionally
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.           5
    achievable. 
    Id.
     at 2:25–31. Claim 17 is representative,
    and recites as follows:
    17. An ultrasonic surgical shears comprising:
    a) an ultrasonic surgical blade;
    b) a clamping arm operable to open and close to-
    ward the blade;
    c) a tissue pad attached to the clamping arm,
    wherein the blade and tissue pad define a clamp-
    ing surface area so that the applied clamp force
    does not exceed a clamping pressure of 210 psi at
    the clamping surface area; and
    d) means for limiting a user applied clamping
    force on the clamping arm creating an average
    predetermined clamping pressure between and in-
    cluding 60 psi and 210 psi on tissue disposed be-
    tween the tissue pad and the blade.
    
    Id.
     at 7:15–27 (emphases added).
    Each asserted claim of the ’501 patent includes at
    least one limitation that requires clamping pressure
    values similar to those recited in claim 17. Ethicon DCt,
    ECF No. 131 at 49. The asserted claims recite either an
    “average” clamping/coaptation pressure (e.g., claims 1 and
    17) or simply a “clamping pressure” (e.g., claims 12, 22,
    and 23). We understand the ’501 patent’s specification to
    use “clamping pressure” interchangeably with “average”
    clamping/coaptation pressure. For example, in describing
    the “method of the invention” as illustrated in Figure 1,
    the specification describes the “exert coaptation pressure”
    step (element 14) as the exertion of “an average coapta-
    tion pressure on the blood vessel between and including
    60 psi and 210 psi.” 
    Id.
     at 3:27–41. The “Summary of the
    Invention” also describes the “method of the invention” as
    the exertion of “an average coaptation pressure on the
    blood vessel between and including 60 psi and 210 psi.”
    6              ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    
    Id.
     at 2:1–4, 2:10–13, 2:18–22. The remainder of the
    specification then refers interchangeably to this key 60
    psi to 210 psi range as either the “average coaptation
    pressure,” the clamping/coaptation pressure, or simply
    “the pressure.” Compare 
    id.
     at 3:38–41 (“average coapta-
    tion pressure”), with 
    id.
     at 5:4–8 (“clamping pressure”), 
    id.
    at 5:41–52 (“coaptation pressure”), and 
    id.
     at 4:17–27
    (“the pressure”). Thus, we understand the ’501 patent’s
    claims to reference average clamping/coaptation pres-
    sures, regardless of whether or not the word “average” is
    expressly recited by the claims.
    The district court found the asserted claims of the
    ’501 patent to be invalid as indefinite, finding that noth-
    ing in the specification or understanding in the art speci-
    fied “a method of measurement, the location of
    measurement, and the type and amount of tissue used for
    the measurement of clamping force[s] and clamping
    pressure[s]” recited by the claims. Ethicon DCt, ECF No.
    131 at 56. The district court was troubled by the fact that
    “measuring at different locations along the clamp arm
    provide[d] different force and pressure values” and “when
    the clamp arm [wa]s fully engaged with tissue, the tissue
    c[ould] be thin or thick, stiff or compressible, and depend-
    ing on the type of tissue, the measurement of the clamp-
    ing force and pressure w[ould] differ.” 
    Id.
     at 56–57.
    Ethicon contends that the district court ignored much
    of Ethicon’s proffered evidence and instead improperly
    resolved disputed issues of fact in favor of the movant,
    Covidien. Ethicon argues that a skilled artisan reading
    the specification would understand that the clamping
    force measurements recited in the claims must be made
    when the clamping arm and blade are in a closed position,
    and in a manner that reflects the average pressure ap-
    plied by the clamping arm on the clamping surface area,
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.             7
    which can be measured at the midpoint of the recited
    clamping surface area—the midpoint of the tissue pad. 1
    We review the district court’s indefiniteness determi-
    nation de novo. Interval Licensing LLC v. AOL, Inc., 
    766 F.3d 1364
    , 1370 (Fed. Cir. 2014). A claim is invalid for
    indefiniteness under 
    35 U.S.C. § 112
     ¶ 2 2 if its language,
    when read in light of the specification and prosecution
    history, fails to inform skilled artisans about the scope of
    the invention with reasonable certainty. Nautilus, Inc. v.
    Biosig Instruments, Inc., 
    134 S. Ct. 2120
    , 2129 (2014).
    Claim 17 of the ’501 patent recites that the claimed
    ultrasonic surgical shears include a tissue pad and blade
    1   At oral argument, Ethicon explained that unlike
    figures 2–5 of the ’501 patent, the tissue pads of Ethicon’s
    ultrasonic shears and Covidien’s accused ultrasonic
    shears extend along their entire respective clamping
    arms. In other words, the midpoint of the tissue pad is at
    substantially the same position as the midpoint of the
    clamping arm. Oral Argument at 11:10–16:20, Ethicon
    Endo-Surgery v. Covidien, Inc., No. 2014-1370 (Fed. Cir.
    Mar. 6, 2015), available at http://www.cafc.uscourts.gov/
    oral-argument-recordings/14-1370/all.       Covidien con-
    firmed Ethicon’s understanding.        
    Id.
     at 21:00–22:10.
    Thus, we interpret the parties’ references in their briefs to
    the midpoint of the recited clamping surface area as
    referring to the midpoint of the clamping arm as it applies
    to the commercial products at issue and the midpoint of
    the tissue pad as it applies to the claims of the ’501 pa-
    tent. See, e.g., ’501 patent, Fig. 2.
    2   Paragraph 2 of 
    35 U.S.C. § 112
     was replaced with
    newly designated § 112(b) when § 4(c) of the Leahy-Smith
    America Invents Act, Pub. L. No. 112-29 (AIA), took effect
    on September 16, 2012. Because the application resulting
    in the patent was filed before that date, we will refer to
    the pre-AIA version of § 112.
    8              ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    that define a clamping surface area. ’501 patent, 7:20–21.
    The specification explains that this “clamping surface
    area is the area where the blade and the tissue pad are in
    close proximity because the clamping arm is in a closed
    position.” Id. at 4:25–27, 1:36–38. In the primary dis-
    closed embodiment, the clamping surface area is about
    0.033 square inches. Id. at 4:14–15. The user operates
    the claimed shears to exert a clamping force of between
    two and seven pounds in order to close the clamping arm
    towards the blade. Id. at 4:15–17. Thus, the clamping
    force on the clamping surface area—defined by the tissue
    pad and the blade—averages between two and seven
    pounds over 0.033 square inches, or between approxi-
    mately 60 to 210 pounds per square inch. See id. at 5:41–
    45; see also id. at 4:61–65.
    The clamping force applied to close the clamping arm
    towards the blade results in the exertion of a clamping
    pressure on a blood vessel disposed between the tissue
    pad attached to the clamping arm and the blade. Id. at
    4:31–37, 3:38–41. See also id. at 4:38–57. The specifica-
    tion makes clear that this clamping or coaptation pres-
    sure on the blood vessel is an average pressure. Id. at
    Abstract; id. at Summary of the Invention, 2:1–4, 2:10–13,
    2:18–22. The specification also makes clear that “[t]he
    pressures discussed [in the ’501 patent] are pressures
    seen by tissue when the entire clamping surface area is in
    contact with the tissue.” Id. at 4:23–25. To ensure that
    no more than 210 psi of pressure is exerted at the clamp-
    ing surface area, the claimed shears include means for
    limiting the clamping force applied by the user on the
    clamping arm. Id. at 7:22–27. Thus, the claimed shears
    limit the average predetermined clamping pressure on
    tissue between the tissue pad and the blade—the clamp-
    ing surface area—to between 60 and 210 psi. Id. at 5:4–
    12.
    As the claims and specification indicate, the user-
    applied clamping force on the clamping arm is translated
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.             9
    to pressure applied by the clamping arm and blade to the
    tissue. See, e.g., id. at 7:22–23 (“[T]he applied clamp force
    does not exceed a clamping pressure of 210 psi at the
    clamping surface area.”); id. at 2:10–13 (“[E]xerting a
    clamping force on the clamping arm creat[es] an average
    clamping pressure between and including 60 psi and 210
    psi on tissue positioned between the tissue pad and the
    blade.”). And the specification is clear that the recited
    “clamping pressure” is an average pressure that should be
    measured when the clamping arm and the blade are in a
    closed position and exerting pressure on a blood vessel
    disposed between them. See, e.g., id. at 2:1–4, 4:23–27.
    Ethicon’s expert explained that as a matter of physics,
    pressure measured by pounds per square inch is calculat-
    ed by taking a force measurement at a point and dividing
    that force by the area. Joint Appendix (J.A.) 4356 ¶ 102.
    Translated to the claims of the ’501 patent, a skilled
    artisan would know that the recited average clamping
    pressures can be determined by measuring the average
    clamping force on the clamping surface area and dividing
    that average force by the clamping surface area. See J.A.
    4427 ¶ 247. And in the case of a simple lever, such as the
    clamping arm of the claimed ultrasonic shears, measured
    force has a generally linear mathematical relationship
    with distance along the lever arm, and the midpoint of the
    lever arm is representative of the average force along the
    arm. Id.; see also J.A. 4366 (“[T]he force varies linearly
    along the length [of the clamping arm] . . . [and] the
    midpoint represents the average along the clamping
    surface.”). Thus, Ethicon’s expert concluded that a person
    of ordinary skill in the art would understand that measur-
    ing the average clamping pressure as recited by the
    claims can be accomplished by measuring the clamping
    force applied by the clamping arm at the midpoint of the
    clamping surface area when the clamping arm is in a
    closed position—the midpoint of the tissue pad (and the
    midpoint of the clamping arm for Ethicon and Covidien’s
    10             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    commercial ultrasonic devices). J.A. 4431 ¶ 261. Ethi-
    con’s expert also conducted tests of Covidien’s accused
    device to illustrate his explanation of the link between
    average pressures and the midpoint of the clamping
    surface area, which demonstrated, inter alia, the general
    linearity of clamping force along the clamping arm, and
    how force measurements at the midpoint of the clamping
    arm approximated the average of two force measurements
    taken at proximal and distal locations 1/3 and 2/3 of the
    way along the clamping arm. Id. at 4366, 4370.
    Covidien offers nothing to contest this explanation of
    the underlying physics- and mathematics-based link
    between the average pressure and the midpoint of the
    clamping arm provided by Ethicon’s expert. Thus, unre-
    butted testimony in the record demonstrates that the
    focus of the ’501 patent’s specification and claims on
    average clamping/coaptation pressures is sufficient to
    signal to a skilled artisan how to arrive at the claimed
    force and pressure measurements. Relying on basic
    concepts of physics and mathematics, skilled artisans
    would understand that the average clamping/coaptation
    pressures recited in the ’501 patent’s claims can be de-
    termined by measuring clamping force at the midpoint of
    the clamping surface area—which for the ultrasonic
    shears at issue here is at the midpoint of both the tissue
    pad and clamping arm.
    The district court appeared to ignore this intrinsic ev-
    idence and the testimony in the record. It expressed
    concern that the claims did not specifically “refer to any
    particular point” on the clamping surface area at which to
    take the recited pressure measurements or “identify a
    location at which [the clamping force] is to be measured.”
    Ethicon DCt, ECF No. 131, at 50–51. The district court
    also expressed concern that there was no industry stand-
    ard method for measuring clamping forces. Id. at 49.
    Indeed, the district court appears to have believed that in
    order for the claims of the ’501 patent to satisfy the defi-
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.            11
    niteness requirement of 
    35 U.S.C. § 112
     ¶ 2, the intrinsic
    evidence needed to identify a specific method one of
    ordinary skill in the art would use to measure the recited
    clamping/coaptation pressures. 
    Id. at 55
    . See also 
    id. at 48, 50
     (same).
    But in the context of the dispute here, the definiteness
    requirement of 
    35 U.S.C. § 112
     mandates only that one
    skilled in the art must be able to understand which
    pressures are relevant to the claims and how those pres-
    sures can be measured, so to discern the scope of the
    claimed average pressure range with reasonable certain-
    ty. See Nautilus, 120 S. Ct. at 2124. If such an under-
    standing of how to measure the claimed average
    pressures was within the scope of knowledge possessed by
    one of ordinary skill in the art, there is no requirement for
    the specification to identify a particular measurement
    technique. As discussed above, evidence in the record
    demonstrates that because the specification and claims of
    the ’501 patent focused on average clamping and coapta-
    tion pressures, a skilled artisan would have possessed
    such an understanding and such knowledge. See J.A.
    4427 ¶ 247; 4356 ¶ 102.
    Instead of focusing on what a skilled artisan would
    have understood about the claimed average pressures
    based on the disclosure in the ’501 patent, the district
    court focused on how Ethicon tested its own commercial
    embodiment of the claimed ultrasonic shears. In doing so,
    the district court was troubled that Ethicon used four
    different methods to measure clamping force, and that
    each of these methods appeared to yield different force
    measurements. Ethicon DCt, ECF No. 131, at 13. It
    found this to create ambiguity in the claims because
    “different methods of measuring clamping force and
    pressure result[ed] in different numeric values.” Id. at 49.
    The district court, however, appears to have based its
    conclusions on mischaracterized testimony, and as a
    result, arrived at several clearly erroneous factual conclu-
    12             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    sions. Although Ethicon’s witnesses testified that Ethicon
    used different techniques to measure clamping force, the
    district court ignored testimony that each of these meth-
    ods was designed to provide the same clamping force
    measurement. J.A. 2685–86 (“[All four methods of meas-
    urement are] trying to achieve the same result, which is
    the force it takes to just bring the clamp arm off the
    blade”). And while the actual tested clamping force
    measurements may have varied slightly between these
    methods, this was simply due to natural variances in real-
    world testing conditions. Ethicon’s witness explained that
    “[i]f you took [results from] all [four of] the methods again
    and again and again, the average of all those [measure-
    ments] should be quite similar to each other.” J.A. 2686.
    The district court also found that clamping forces of
    Ethicon’s shears measured at the distal end of its clamp-
    ing arm were lower, and clamping forces measured near
    the grip area of the shears were higher, than clamping
    forces measured at its midpoint. Ethicon DCt, ECF No.
    131, at 18. The district court believed this also demon-
    strated the claims were indefinite. Id. at 50. The district
    court, however, ignored testimony providing context for
    the differing force measurements at the proximal and
    distal ends of the clamping arm. There is no dispute that
    force measurements along the clamping arm vary. But as
    discussed above, when the clamping arm of Ethicon’s
    ultrasonic shears is in the closed position, a skilled arti-
    san would know that the force applied by the clamping
    arm will be linearly related to the distance along the
    clamping arm where that force is measured. J.A. 4356
    ¶ 102. A skilled artisan would also know that in order to
    find the average force applied by the clamping arm, he or
    she could measure the forces at the midpoint of the clamp-
    ing surface area—which for Ethicon’s surgical shears is
    the midpoint shared by both the tissue pad and clamping
    arm. Id.; see also J.A. 2698.
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.             13
    Finally, the district court found that the clamping
    force measurements at the clamping surface area of
    Ethicon’s shears varied based on differing heights be-
    tween the tissue pad and the blade, differences which
    resulted from the type and amount of tissue to be tran-
    sected and then sealed. Ethicon DCt, ECF No. 131 at 20.
    There is no dispute that pressures measured at the same
    position along the clamping arm vary when the clamping
    arm is at different angles with the blade. See, e.g., J.A.
    4395 ¶ 147 (“[T]he data upon which [Covidien’s expert]
    relied . . . indicate that the clamp arm force clearly in-
    creases with increasing clamp arm angle. This is to be
    expected . . . .”). But this is immaterial to the scope of the
    claims, which are concerned with average clamp-
    ing/coaptation pressures at the clamping surface area, or
    the “area where the blade and the tissue pad are in close
    proximity when the clamping arm is in a closed position.”
    ’501 patent, 4:25–27. See also id. at 4:23–25 (“The pres-
    sures discussed herein are pressures seen by tissue when
    the entire clamping surface area is in contact with the
    tissue.” (emphasis added)). Thus, while the thickness of
    tissue disposed between the tissue pad and blade may
    affect the amount of clamping force required to operate
    the clamping arm and fully transect that tissue, such
    variances are irrelevant to the scope of the claims, which
    are concerned with the predetermined pressures meas-
    ured when the clamping arm is already in a closed posi-
    tion.
    Based on its evaluation of the extrinsic evidence, the
    district court found the claims of the ’501 patent to “close-
    ly resemble” the claims found to be indefinite in Honey-
    well Int’l, Inc. v. Int’l Trade Comm’n, 
    341 F.3d 1332
    , 1338
    (Fed. Cir. 2003). The claims in Honeywell were directed
    to a process for manufacturing a particular type of multi-
    filament polyester yarn. 
    Id. at 1334
    . The parties’ dispute
    focused on the measurement of a claimed melting point
    elevation feature, which required the production of a
    14             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    sample yarn specimen. 
    Id. at 1336
    . Although the specifi-
    cation did not disclose any sample preparation methods,
    the parties identified four such methods purportedly
    known to those in the art. 
    Id.
     Because each sample
    preparation method produced differing melting point
    elevation ranges, knowledge of the specific sample prepa-
    ration method used was critical to discerning whether
    yarn had been produced using the claimed process. 
    Id.
    We found the claims to be indefinite because nothing in
    the specification or prosecution history provided guidance
    as to which of the critical sample preparation methods a
    skilled artisan would have interpreted the claims to
    require. 
    Id. at 1340
    .
    The district court analogized the four undisclosed
    sample preparation methods in Honeywell to the four
    methods used by Ethicon to measure average clamping
    pressures of its commercial product here, concluding that
    the failure of the ’501 patent to identify a specific method
    for measuring the clamping pressures recited by the
    claims rendered the claims ambiguous and indefinite.
    Ethicon DCt, ECF No. 131, at 54. The district court,
    however, did not appreciate several key distinctions
    between the facts here and the facts in Honeywell. First,
    in Honeywell, there was evidence in the record—in the
    form of prior art references—that skilled artisans knew of
    three sample preparation techniques to measure the
    claimed feature. 
    341 F.3d at 1340
    . The fourth technique
    was disclosed only in the patentee’s confidential files and
    the record contained no evidence that this method was
    known by those in the art. 
    Id. at 1336, 1340
    . Second, it
    was undisputed that only this unpublished sample prepa-
    ration technique provided measurements of the claimed
    feature that fell within the claimed ranges. 
    Id. at 1336
    .
    Third, the different sample preparation techniques pro-
    duced measurements of the claimed feature that “var[ied]
    greatly.” 
    Id.
     Moreover, the patentee did not dispute that
    identifying the selected sample preparation technique was
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.            15
    “critical to discerning whether a particular product [wa]s
    made by a process that infring[ed] the [patent at issue’s]
    claims.” 
    Id. at 1339
    .
    Here, the specification clearly discloses that the
    claimed clamping/coaptation pressures are average pres-
    sures on tissue disposed between the tissue pad and
    blade, and are measured when the clamping arm and
    blade are in a closed position. This disclosure is sufficient
    to inform skilled artisans as to where these average
    pressures should be measured—the midpoint of the tissue
    pad (also the midpoint of the clamping arm for the ultra-
    sonic shears at issue here). See, e.g., J.A. 4356 ¶ 102. In
    contrast, the intrinsic evidence in Honeywell provided no
    guidance as to how to measure a critical element recited
    by the claims (the melting point elevation range), and the
    only method of measurement that satisfied the claimed
    process was not only absent from the specification, but
    also unpublished outside the patentee’s confidential files.
    In addition, the extrinsic evidence in the record here
    shows that although there are different methods of meas-
    uring the claimed average pressures, each of these meth-
    ods is designed to provide similar measurements, whereas
    the different methods of measurement in Honeywell
    produced widely varying results. The district court’s
    reliance on Honeywell is misplaced; Honeywell involved
    factual circumstances that differ from the circumstances
    here in several important ways.
    In short, the district court erred by finding the claims
    of the ’501 patent indefinite under 
    35 U.S.C. § 112
     ¶ 2. A
    skilled artisan, in view of the specification, would under-
    stand the scope of the claims with reasonable certainty.
    We therefore reverse the district court’s grant of
    Covidien’s motion for summary judgment of invalidity for
    indefiniteness.
    16             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    B. The ’275 patent
    The ’275 patent focuses on a different aspect of the ul-
    trasonic surgical shears disclosed in the ’501 patent. In
    particular, the ’275 patent claims a particular configura-
    tion of an ultrasonic surgical shears device that generates
    and then propagates ultrasonic energy to the clamping
    end of the device, while dampening undesired vibrations.
    ’275 patent, 2:3–7. The specification explains that the
    device includes a generator, a grip, a semi-flexible acous-
    tic transmission rod, and a sheath around that rod. 
    Id.
     at
    3:47–51, 7:52–64. An “end effector,” such as the clamping
    arm and blade assembly covered by the ’501 patent, is
    attached to the distal end of the acoustic transmission
    rod. See 
    id.
     at 3:61–4:19. The generator transmits an
    electrical signal to a transducer, which converts the
    electrical energy into vibrational motion at ultrasonic
    frequencies. 
    Id.
     at 1:12–15, 3:51–57. This vibrational
    motion results in longitudinal waves of ultrasonic energy
    that propagate through the acoustic assembly in a stand-
    ing wave at a selected frequency and amplitude. 
    Id.
     at
    3:57–61. The end effector, such as a clamping arm and
    blade, transfers the received ultrasonic energy to tissue
    (like blood vessels) disposed between the clamping arm
    and blade. 
    Id.
     at 3:61–63. In addition to cutting the
    tissue, heat generated by the friction from the blade
    vibrating against the tissue causes proteins in the tissue
    to denature, resulting in the formation of a coagulum,
    which then helps to seal the cut tissue. 
    Id.
     at 3:66–4:6.
    The ’275 patent explains that only the transmitted
    axial (or longitudinal) vibrational motion—vibrations that
    move directly forward and backward along the transmis-
    sion rod towards the blade and clamping arm—is desira-
    ble.    
    Id.
     at 1:22–23.      Transverse—or side-to-side—
    vibrational motion can lead to sub-optimal performance
    and even damage the device. 
    Id.
     at 1:25–30. To reduce
    transverse vibrational motion, the device includes a
    damping sheath that “loosely surrounds” the transmission
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.            17
    rod. 
    Id.
     at 9:33–39. The specification explains that this
    sheath is attached to the transmission rod at nodal points,
    or points at which the ultrasonic standing wave vibrating
    through the transmission rod is at its minimum ampli-
    tude. 
    Id.
     at 9:40–41, 5:57–60.
    Ethicon asserted infringement of Claims 1 and 3 of
    the ’275 patent. Ethicon DCt, ECF No. 130, at 1. Claim 3
    depends from claim 1, which recites:
    1. An ultrasonic surgical device comprising:
    a transducer assembly adapted to vibrate at an
    ultrasonic frequency in response to electrical en-
    ergy;
    a mounting device having a first end and a second
    end, the mounting device adapted to receive ultra-
    sonic vibration from the transducer assembly and
    to transmit the ultrasonic vibration from the first
    end to the second end of the mounting device, the
    first end of the mounting device coupled to the
    transducer assembly;
    a transmission rod having a first end and a second
    end, the transmission rod adapted to receive ul-
    trasonic vibration from the mounting device and
    to transmit the ultrasonic vibration from the first
    end to the second end of the transmission rod;
    a damping member surrounding at least a portion
    of the transmission rod, the damping member con-
    figured to loosely contact the transmission rod over
    a portion of the transmission rod, the damping
    member adapted to absorb undesired vibrations
    along the transmission rod without the use of a
    fluid; and
    an end effector having a first end and a second
    end, the end effector adapted to receive the ultra-
    sonic vibration from the transmission rod and to
    18              ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    transmit the ultrasonic vibration from the first
    end to the second end of the end effector, the sec-
    ond end of the end effector being disposed near an
    antinode and the first end of the end effector cou-
    pled to the second end of the transmission rod.
    ’275 patent at 16:50–17:10 (emphasis added).
    After the close of discovery, Covidien filed a motion for
    summary judgment of noninfringement, contending that
    the damping sheath surrounding the transmission rod of
    its accused ultrasonic shears is not “configured to loosely
    contact” the transmission rod or “adapted to absorb
    undesired vibrations.” Ethicon DCt, ECF No. 130, at 2.
    The district court granted Covidien’s motion, finding no
    genuine dispute that Covidien’s accused ultrasonic shears
    did not satisfy either of those limitations. 
    Id. at 21
    , 26–
    27. On appeal, Ethicon challenges the district court’s
    construction of “loosely contact” and contends that the
    district court improperly resolved disputed issues of fact
    and conflicting expert testimony in Covidien’s favor.
    We begin first with Ethicon’s challenge to the district
    court’s claim construction. The district court construed
    “configured to loosely contact” as “structured to have
    contact other than at fixed support points, but not tightly
    fitted.” Ethicon DCt, No. 11–cv–871, 
    2013 WL 1787153
    ,
    at *7–8 (S.D. Ohio Apr. 25, 2013). Ethicon contends that
    the district court imported a limitation into the term
    inconsistent with its ordinary meaning—that “loose[]
    contact” is contact “other than at fixed support points.”
    According to Ethicon, nothing in the specification limits
    where this “loose contact” can occur, and thus that “loose
    contact” encompasses embodiments in which contact
    occurs only at fixed support points such as the “nodal
    ribs” where the damping sheath of Covidien’s accused
    ultrasonic shears is attached to its transmission rod.
    After review of the disputed term, we arrive at the same
    construction as did the district court.
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.          19
    We review the district court’s claim construction here
    de novo because it relied only on evidence intrinsic to the
    ’275 patent. See Teva Pharm. USA, Inc. v. Sandoz, Inc.,
    
    135 S. Ct. 831
    , 841 (2015). The words of a claim are
    generally given their ordinary and customary meaning,
    which is the meaning that the term would have to a
    person of ordinary skill in the art in question at the time
    of the invention. Phillips v. AWH Corp., 
    415 F.3d 1303
    ,
    1312–13 (Fed. Cir. 2005) (en banc) (internal citations
    omitted). Claim language must be viewed in light of the
    specification, which is the “single best guide to the mean-
    ing of a disputed term.” 
    Id. at 1315
     (quoting Vitronics
    Corp. v. Conceptronic, Inc., 
    90 F.3d 1576
    , 1582 (Fed. Cir.
    1996)).
    Claim 1 recites that the damping sheath surrounding
    the transmission rod “loosely contact[s] the transmission
    rod over a portion of the transmission rod.” ’275 patent,
    16:66–67 (emphasis added). The recitation of “over a
    portion” suggests that such “loose contact” is not contact
    only at discrete fixed points, as Ethicon contends. The
    specification reinforces this understanding, explaining
    that a longitudinal slit extends along the damping sheath
    from one end to the other in order to allow the sheath to
    fit over the transmission rod. 
    Id.
     at 10:52–54, 10:65–11:7.
    Without the slit, the damping sheath “may not be able to
    loosely contact the transmission rod” over its cross-
    sectional diameter. 
    Id.
     at 10:53–55. See also 
    id.
     at 9:58–
    60 (“The damping sheath 160 is preferably in light contact
    with the transmission rod 86 to absorb unwanted ultra-
    sonic energy from the transmission rod.” (emphasis add-
    ed)).
    Moreover, the specification explains that this damp-
    ing sheath “is more effective than using silicone rubber
    rings [‘nodal ribs’] located only at nodes of longitudinal
    vibration.” 
    Id.
     at 10:7–9. This is because the damping
    sheath can “dampen transverse motion occurring near
    multiple antinodes of the unwanted vibration which are
    20             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    located randomly along the length of the transmission
    rod.” 
    Id.
     at 10:9–12. Antinodes are points at which the
    ultrasonic standing wave vibrating through the transmis-
    sion rod is at its absolute value maximum, or peak, ampli-
    tude. 
    Id.
     at 5:60–62. In short, the specification touts the
    benefits of the sheath for its ability to dampen vibrations
    along the full length of the transmission rod instead of
    only at certain fixed points. Thus, the specification
    strongly suggests that the desirable “loose contact” be-
    tween the sheath and transmission rod is contact other
    than at only fixed points. In particular, this “loose con-
    tact” occurs at various portions of the sheath in between
    fixed nodes of the transmission rod, where the amplitude
    of the ultrasonic standing wave is at its peak. We find
    nothing in the specification supporting the notion that
    contact between the damping sheath and the transmis-
    sion rod only at nodal ribs is “loose contact.” We therefore
    affirm the district court’s construction of “configured to
    loosely contact.”
    Based on its construction, the district court found that
    the transmission rod of Covidien’s accused ultrasonic
    shears only contacted its damping sheath at fixed nodal
    rib supports, and thus did not satisfy the “loosely contact”
    limitation of the asserted claims. Ethicon DCt, ECF No.
    130, at 17–18. The district court also found that because
    there was no evidence the transmission rod of Covidien’s
    accused shears contacted the sheath, there was no evi-
    dence that the sleeve “absorb[ed] unwanted vibrations
    along the transmission rod,” as required by the asserted
    claims. Id. at 22. Ethicon contends there are genuine
    issues of material fact as to 1) whether even under the
    district court’s construction of “loosely contact,” the damp-
    ing sheath of Covidien’s accused ultrasonic shears “loosely
    contacts” its transmission rod, and 2) whether Covidien’s
    accused shears are “adapted to absorb undesirable vibra-
    tions.” We agree with Ethicon.
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.           21
    We turn first to the district court’s determination that
    there is no genuine dispute of material fact that the
    damping sheath of Covidien’s accused ultrasonic shears
    does not “loosely contact[]” its transmission rod. Neither
    party disputes that the sleeve of Covidien’s shears is
    supported by fixed nodal ribs on its transmission rod, and
    that because these ribs have a greater diameter than the
    rest of the transmission rod, there is some amount of
    space along the length of the transmission rod separating
    the sheath from the transmission rod. Id. at 18. The
    district court found that because the nodal ribs were
    raised, contact between the sheath and the transmission
    rod was avoided. Id. The district court also determined
    that even if the accused sheath was capable of contacting
    the transmission rod, summary judgment would still be
    appropriate because there was no evidence that the
    accused sheath was “structured to have contact” at loca-
    tions other than the fixed nodal ribs. Id. at 19.
    In particular, the district court relied on testimony
    from Covidien’s engineers that Covidien sought to design
    the sheath of its accused device so that it would not
    “loosely contact” the transmission rod. Id. at 19–20. This
    finding, however, did not take into account contrary
    evidence and testimony from Ethicon’s expert, J.A.
    3604, showing that the sheath of Covidien’s accused
    shears appeared to contact its transmission rod at points
    other than the nodal ribs during operation. Specifically,
    Ethicon’s expert examined two sets of high-resolution
    computer axial tomography (CT) and X-ray scans gener-
    ated during tests of Covidien’s accused shears, testifying
    that it was his opinion that both sets of scans showed
    loose contact at points other than the fixed nodal ribs.
    J.A. 3603, 3617–18.
    Covidien’s expert disputed the testimony of Ethicon’s
    expert, opining that most of the scans did not show any
    contact between the sheath and transmission rod. J.A.
    2165. However, Covidien’s expert conceded that at least
    22             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    one of the scans did show contact, but argued that such
    contact was due to a nonconforming “wrinkle” in the
    sheath. J.A. 2165–66; see also Appellee’s Br. 39–40
    (“[Although the CT scans at issue] may reflect contact of
    the [sheath] and [transmission rod] between the nodal
    ribs, any contact was due to a nonconforming ‘wrinkle’ in
    the sleeve component of that particular instrument.”).
    There is no evidence in the record, however, to support
    the expert’s assertion that this alleged wrinkle was in-
    deed nonconforming.        See J.A. 3630 (“Q. Did you
    [Covidien’s expert] ever discuss this wrinkle with any of
    the engineers at Covidien? A. No.”); J.A. 3631 (“Q. Does
    Covidien do imaging of every [accused] device to deter-
    mine that it is wrinkle-free before leaving the factory? A.
    Don’t know.’). In short, it is clear that genuine disputes
    remain as to whether the sheath of Covidien’s accused
    ultrasonic shears “loosely contacts” its transmission rod.
    We turn next to the district court’s determination that
    there is no genuine dispute of material fact that the
    damping sheath of Covidien’s accused ultrasonic shears is
    not “adapted to absorb undesired vibrations along the
    transmission rod.” The district court found there was no
    proof that Covidien’s accused shears experienced unde-
    sired transverse vibrations and no proof that the accused
    shears absorbed those vibrations. Ethicon DCt, ECF No.
    130, at 24. To reach this conclusion, the district court
    first relied on testimony from a Covidien expert, who
    performed certain water and glycerin droplet tests which
    purported to show that the transmission rod of Covidien’s
    ultrasonic shears did not experience any undesired trans-
    verse vibrations. Id. at 22. Next, as with the “loosely
    contact” limitation, the district court was persuaded by
    Covidien testimony that its accused shears were “purpose-
    fully designed” to avoid unwanted transverse vibrations.
    In particular, the district court relied on testimony of
    Covidien’s engineers that the transmission rod of its
    accused ultrasonic shears was designed to be symmetrical
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.           23
    and to resonate only in the longitudinal—and not trans-
    verse—direction, and that contact between the transmis-
    sion rod and sheath at points other than fixed nodal ribs
    was identified as a “failure mode” of the sheath. Id. at 22,
    26. The district court, noting there was no dispute that
    undesired transverse vibrations were generated by
    asymmetry of the transmission rod, thus concluded that
    Covidien’s shears were designed to avoid generating
    transverse vibrations “by mechanical design.” Id.
    The district court, however, improperly discounted
    clear evidence that the transmission rod of Covidien’s
    accused ultrasonic shears did experience transverse
    vibrations during testing. In particular, Covidien’s expert
    performed a “droplet test,” in which he placed droplets of
    water or glycerin on the transmission rod of Covidien’s
    accused shears. This test was performed on a fully as-
    sembled device by having the sleeve removed and win-
    dows cut into the sheath. According to Covidien’s expert,
    if the droplets splattered off the transmission rod, there
    were transverse vibrations, and if not, there were no
    transverse vibrations. Although Covidien’s expert testi-
    fied that he saw no droplets splatter, Ethicon’s expert
    testified that he repeated the test using glycerine and
    observed the test fluid flying off tangentially from the
    transmission rod. J.A. 3688.
    In addition, the district court’s conclusion that
    Covidien’s accused ultrasonic shears were designed to
    avoid transverse vibrations is also based on an incomplete
    view of the record. In particular, the district court’s
    reliance on the symmetry of Covidien’s transmission rod
    as evidence that the accused shears avoided transverse
    vibrations “by mechanical design” is contradicted by
    testimony from Covidien’s own witnesses, who testified
    that the transmission rod was actually asymmetrical.
    J.A. 3604 (“[W]e don’t live in a perfect world, so there are
    straightness, curvatures of parts that are natural within
    the part . . . .”). In addition, the district court did not
    24             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    address evidence in the record that Covidien’s manufac-
    turing tolerances for the transmission rod allowed for a
    certain amount of variance that could result in asymme-
    tries of the rod. J.A. 3605. Moreover, self-serving testi-
    mony from Covidien’s witnesses about the purported goal
    of its product design does not negate the evidence in the
    record, as discussed above, supporting the possible con-
    clusion that the transmission rod of the accused shears
    actually did experience unwanted transverse vibrations.
    Taking all inferences in favor of the non-movant Ethi-
    con, disputed issues of material fact remain as to whether
    Covidien’s accused ultrasonic shears infringe or do not
    infringe the asserted claims of the ’275 patent. Rather
    than properly evaluating the evidence in the light most
    favorable to the nonmoving party, the district court
    appears to have impermissibly resolved factual disputes
    in favor of Covidien in order to reach its conclusions. We
    therefore vacate the district court’s grant of summary
    judgment of noninfringement of claims 1 and 3 of the ’275
    patent. 3
    3  We note that Ethicon also argues that the district
    court ignored testimony by Covidien’s own witnesses that
    the sheath of its accused device was “designed to contact”
    the transmission rod in order to prevent the rod from
    touching the inner diameter of an inner tube. J.A. 3649.
    Preventing such contact reduced the probability of an
    audible “squealing” when the two components touched.
    Id. But Ethicon does not show how the presence of
    “squealing” signals the presence of transverse vibrations,
    which are the “undesired” vibrations recited by the
    claims. Nor does Ethicon explain how such “squealing”
    provides evidence that the sheath absorbs transverse
    vibrations of the transmission rod.
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.         25
    C. The Design Patents
    The Design Patents claim particular ornamental de-
    signs of an ultrasonic surgical device. The D’801 patent
    claims a particular ornamental design of an inverted “U”-
    shaped trigger. The D’802 patent claims the overall
    appearance of the ornamental design of the “U”-shaped
    trigger and the particular ornamental design of a rounded
    and fluted torque knob positioned above and forward from
    the trigger. The D’803 patent claims the overall appear-
    ance of the ornamental design of the “U”-shaped trigger
    and the particular ornamental design of a rounded activa-
    tion button positioned directly above the trigger. The
    D’804 patent claims the overall appearance of the orna-
    mental designs of the “U”-shaped trigger, the fluted
    torque knob, and the rounded activation button, with the
    torque knob and the button positioned relative to the
    trigger as in the D’802 and D’803 patents, respectively. A
    figure from the D’804 patent, depicting the ornamental
    designs of the trigger, torque knob, and button claimed in
    various combinations and relative positions by the Design
    Patents, is reproduced below:
    26             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    The district court concluded that the claimed designs
    in the Design Patents were all dictated by function and
    were therefore invalid. Ethicon DCt, ECF No. 132, at 22.
    Specifically, the district court determined that under each
    consideration for assessing functionality identified in
    PHG Technologies v. St. John Companies, 
    469 F.3d 1361
    ,
    1366 (Fed. Cir. 2006), Ethicon’s claimed designs were
    dictated by function. In the alternative, the district court
    found that because each of the designs of the trigger,
    torque knob, and button must be “factored out” under
    Richardson v. Stanley Works, Inc., 
    597 F.3d 1288
     (Fed.
    Cir. 2010), the Design Patents had no scope, and therefore
    Covidien’s accused design could not infringe the Design
    Patents. Ethicon DCt, ECF No. 132, at 23–24. The
    district court also found that even if the functional ele-
    ments were not factored out, there was no infringement
    under the ordinary observer test laid out in Egyptian
    Goddess, Inc. v. Swisa, Inc., 
    543 F.3d 665
     (Fed. Cir. 2008)
    (en banc). Specifically, the district court found that the
    “highly sophisticated” ordinary observer in the “highly
    complex medical device purchasing process” would find
    that the claimed designs and the design of Covidien’s
    accused ultrasonic shears were plainly dissimilar. Ethi-
    con DCt, ECF No. 25–26.
    1. Invalidity
    Design patents enjoy the same presumption of validi-
    ty as utility patents under 
    35 U.S.C. § 282
    . L.A. Gear,
    Inc. v. Thom McAn Shoe Co., 
    988 F.2d 1117
    , 1123 (Fed.
    Cir. 1993); 
    35 U.S.C. § 171
    . Thus, Covidien has the
    burden to prove invalidity of the Design Patents by clear
    and convincing evidence. Microsoft v. i4i Ltd. P’ship, 
    131 S. Ct. 2238
    , 2242 (2011); L.A. Gear, 
    988 F.2d at 1124
    . We
    have described as “stringent” this standard as it applies to
    invalidating design patents on grounds of functionality.
    Rosco, Inc. v. Mirror Lite Co., 
    304 F.3d 1373
    , 1378 (Fed.
    Cir. 2002). We review the district court’s finding that the
    patented designs are dictated by their function for clear
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.             27
    error. Best Lock Corp. v. Ilco Unican Corp., 
    94 F.3d 1563
    ,
    1566 (Fed. Cir. 1996).
    Articles of manufacture necessarily serve a utilitarian
    purpose, but design patents are directed to ornamental
    designs of such articles. 
    35 U.S.C. § 171
    . If a particular
    design is essential to the use of an article, it cannot be the
    subject of a design patent. L.A. Gear, 
    988 F.2d at 1123
    .
    We have found designs to be essential to the use of an
    article when the claimed design is “dictated by” the use or
    purpose of the article. 
    Id.
     (citing In re Carletti, 
    328 F.2d 1020
    , 1022 (CCPA 1964); Power Controls Corp. v. Hy-
    brinetics, Inc., 
    806 F.2d 234
    , 238 (Fed. Cir. 1986)). Design
    patents on such primarily functional rather than orna-
    mental designs are invalid. PHG Techs., 
    469 F.3d at 1366
    ; see also Bonito Boats, Inc. v. Thunder Craft Boats,
    Inc., 
    489 U.S. 141
    , 148 (1989).
    In determining whether a claimed design is primarily
    functional, “[t]he function of the article itself must not be
    confused with ‘functionality’ of the design of the article.”
    Hupp v. Siroflex of Am., Inc., 
    122 F.3d 1456
    , 1462 (Fed.
    Cir. 1997). In Hupp, we separated the function inherent
    in a concrete mold—producing a simulated stone pathway
    by molding concrete—from the particular pattern of the
    stone produced by the mold itself—an aesthetic design
    choice. 
    Id. at 1461
    . Thus, even though the claimed
    design pattern was embedded within the functional
    concrete mold, the proper analysis required a determina-
    tion of whether the design pattern within the mold—and
    not the concrete mold itself—was “dictated by” its func-
    tion. Because there was no utilitarian reason the mold
    had to impress the particular claimed rock walkway
    pattern into the concrete, we determined that the claimed
    design was “primarily ornamental,” and not invalid as
    functional. 
    Id.
     In High Point Design LLC v. Buyers
    Direct, Inc., we found that the district court had incorrect-
    ly relied on the functional aspects of a slipper—a seam
    connecting two components, a curved front accommodat-
    28             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    ing the foot, an opening facilitating ingress and egress of
    the foot, a forward lean of the heel keeping the heel in
    place, and a fleece interior providing warmth—to find the
    particular ornamental design of that slipper to be imper-
    missibly functional. 
    730 F.3d 1301
    , 1316 (Fed. Cir. 2013).
    We explained that a claimed design was not invalid as
    functional simply because the “primary features” of the
    design could perform functions. 
    Id.
     As with its analysis
    on other validity grounds, the district court used “too a
    high a level of abstraction” in assessing the scope of the
    claimed design. 
    Id. at 1314
    .
    By contrast, in Best Lock, we affirmed a district
    court’s determination that a design patent to the blade of
    a key was invalid as functional, finding no clear error in
    the district court’s conclusion that the claimed key blade
    design was dictated by functional concerns. 
    94 F.3d at 1567
    . In Best Lock, the claimed design was limited to a
    specific shape of a blank key blade. 
    Id. at 1566
    . The
    parties did not dispute that the claimed key blade shape
    was designed specifically to perform its intended func-
    tion—to fit into a similarly-shaped cylinder lock keyhole.
    
    Id.
     Further, the patentee presented no evidence of alter-
    native compatible key blade designs, admitting that no
    differently-shaped key blade could fit into the keyhole of
    the corresponding cylinder lock. 
    Id.
     Because no alterna-
    tive design would allow the underlying article to perform
    its intended function, we determined the district court did
    not clearly err by finding that the claimed key blade
    design was dictated by function, and therefore invalid. 
    Id. at 1567
    .
    We have also instructed that the overall appearance
    of the article—the claimed design viewed in its entirety—
    is the basis of the relevant inquiry, not the functionality
    of elements of the claimed design viewed in isolation. For
    example, we acknowledged in L.A. Gear that certain
    elements comprising the claimed design of an athletic
    sneaker each had a utilitarian purpose, including a “delta
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.          29
    wing” supporting the foot and reinforcing the shoelace
    eyelets, side mesh paneling further supporting the foot, a
    “moustache” at the back of the shoe cushioning the Achil-
    les tendon and reinforcing the rear of the shoe, and the
    particular positioning of each of these elements within the
    design of the shoe. 
    988 F.2d at 1123
    . Nevertheless, we
    explained that “the utility of each of the various elements
    that comprise the design is not the relevant inquiry with
    respect to a design patent” because whether a design is
    primarily functional or primarily ornamental requires
    viewing the claimed design “in its entirety.” 
    Id.
     See also
    Berry Sterling Corp. v. Pescor Plastics, Inc., 
    122 F.3d 1452
    , 1455 (Fed. Cir. 1997) (“[T]he determination of
    whether [a] patented design is dictated by the function of
    the article of manufacture must ultimately rest on an
    analysis of its overall appearance.” (emphasis added)).
    We have not mandated applying any particular test
    for determining whether a claimed design is dictated by
    its function and therefore impermissibly functional. We
    have often focused, however, on the availability of alter-
    native designs as an important—if not dispositive—factor
    in evaluating the legal functionality of a claimed design.
    For example, the district court in L.A. Gear referenced the
    evidence of many alternative designs that accomplished
    the same functionality associated with the underlying
    athletic sneaker. 
    988 F.2d at 1123
    . In view of that evi-
    dence, we noted that “[w]hen there are several ways to
    achieve the function of an article of manufacture, the
    design of the article is more likely to serve a primarily
    ornamental purpose. 
    Id.
     See also Rosco, 
    304 F.3d at 1378
    (“[I]f other designs could produce the same or similar
    functional capabilities, the design of the article in ques-
    tion is likely ornamental, not functional.”); Best Lock, 
    94 F.3d at 1566
     (same); Hupp, 
    122 F.3d at 1460
     (same).
    Here, the district court appeared to discount the ex-
    istence and availability of alternative designs in deter-
    mining that the claimed Design Patents were “primarily
    30              ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    functional” based on its evaluation of the five considera-
    tions identified in PHG, 
    469 F.3d at 1366
     (quoting Berry
    Sterling, 
    122 F.3d at 1456
    ). In Berry Sterling, we vacated
    and remanded a district court’s grant of summary judg-
    ment of invalidity where it had failed to “elicit the appro-
    priate factual underpinnings for a determination of
    invalidity of a design patent due to functionality.” 122
    F.3d at 1454. In our instructions on remand, we ex-
    plained that where the existence of alternative designs is
    not dispositive of the invalidity inquiry, the district court
    may look to several other factors for its analysis:
    whether the protected design represents the best
    design; whether alternative designs would ad-
    versely affect the utility of the specified article;
    whether there are any concomitant utility pa-
    tents; whether the advertising touts particular
    features of the design as having specific utility;
    and whether there are any elements in the design
    or an overall appearance clearly not dictated by
    function.
    Id. at 1456. We explained that evaluating these other
    considerations “might” be relevant to assessing whether
    the overall appearance of a claimed design is dictated by
    functional considerations. Id.; High Point, 730 F.3d at
    1315 (“Assessing [these five] factors may help determine
    whether a claimed design, as a whole, is ‘dictated by’
    functional considerations.” (emphasis added)).       Thus,
    while the Berry Sterling factors can provide useful guid-
    ance, an inquiry into whether a claimed design is primari-
    ly functional should begin with an inquiry into the
    existence of alternative designs.
    Ethicon presented evidence of alternative ornamental
    designs that could provide the same or similar functional-
    ity of the underlying ultrasonic shears. For example,
    Ethicon’s expert testified that “there [we]re many differ-
    ent designs that would function just as well” as the de-
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.           31
    signs claimed in the Design Patents. J.A. 4807–18 ¶¶ 48–
    56. Ethicon’s expert also identified multiple alternative
    designs for hand-held surgical devices in the prior art. Id.
    at 4813–18 ¶¶ 50, 51, 55. Covidien’s expert admitted that
    other trigger designs, for example, would “work well” but
    “look different.” J.A. 5125. Indeed, Covidien does not
    contend on appeal that there are no alternatives to the
    claimed designs, but merely argues that such designs
    cannot be considered true alternatives because, as the
    district court found, they did not work “equally well” as
    the claimed designs. Appellee’s Br. 52–53.
    The foregoing evidence does not support the district
    court’s grant of summary judgment that the claimed
    designs are primarily functional for two reasons. First,
    the district court’s determination that the designs did not
    work “equally well” apparently describes the preferences
    of surgeons for certain basic design concepts, not differ-
    ences in functionality of the differently designed ultrason-
    ic shears. For example, in supporting its conclusion that
    alternative designs “would not have worked as well” as
    the claimed design, the district court pointed to testimony
    that surgeons preferred ultrasonic shears with certain
    basic design features like activation buttons on the front,
    rather than the rear of the device, “open” triggers, rather
    than closed or loop-style triggers, and forward positions,
    as opposed to other positions, for placement of the torque
    knob. Ethicon DCt, ECF No. 132, at 18–19.
    Second, to be considered an alternative, the alterna-
    tive design must simply provide “the same or similar
    functional capabilities.” Rosco, 
    304 F.3d at 1378
     (revers-
    ing functionality finding because alternative mirror
    designs could still provide a similar level of performance);
    see also Seiko Epson Corp. v. Nu-Kote Intern., Inc., 
    190 F.3d 1360
    , 1368 (Fed. Cir. 1999) (explaining that to be
    patentable, there cannot only be one “possible [ornamen-
    tal] form of the article that could perform its function”).
    Here, there is no dispute that the underlying ultrasonic
    32             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    shears could still function in the same manner with a
    differently-shaped open trigger, activation button, and
    torque knob, and different relative locations of the trigger,
    button, and torque knob. See Ethicon DCt, ECF No. 132,
    at 18 (acknowledging that alternative designs exist).
    Indeed, Covidien identifies no evidence or testimony that
    the particular appearance and shape of the open trigger,
    torque knob, or activation button provided utilitarian
    advantages over other ornamental designs of those ele-
    ments.
    Further, the district court’s functionality inquiry used
    too high of a level of abstraction. Instead of focusing on
    whether the specific patented designs had a functional
    purpose—the continuously curved “U” shape of the open
    trigger having tapered handles with ends flaring out-
    wards, the football-shape of the activation button, and the
    asymmetrically-fluted torque knob with a flat front face—
    the district court focused its PHG analysis on the func-
    tional characteristics that any design of an open trigger,
    button, and torque knob would have for the underlying
    ultrasonic shears.
    For example, the district court supported its conclu-
    sion that the claimed designs were “primarily functional”
    using testimony from Ethicon witnesses that the chosen
    design was “the best design ergonomically” of those con-
    sidered for Ethicon’s commercial product. Ethicon DCt,
    ECF No. 132, at 18. This ergonomic choice, however, was
    not a choice between different open trigger designs, but
    rather between the concept of an open trigger and a
    thumb-ring or loop-shaped trigger. J.A. 5573 ¶ 19 (“Part
    of [Ethicon’s] decision to use a shepherd’s hook trigger
    [i.e., an open trigger] instead of a thumb-ring or loop-
    shaped trigger design stemmed from the aesthetic value
    of the shepherd’s hook design.”). This same evaluation of
    an open trigger guided the district court’s determination
    that alternative designs would not have worked as well as
    an open trigger because surgeons preferred the chosen
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.            33
    design to alternatives. And as discussed above, the
    surgeon-preferred design was not the specific patented
    design, but rather the general concept of an “open trigger”
    versus a “closed trigger” design. J.A. 3058 (Tr. 272:14–22)
    (Q. “What about changing the [open trigger design] to a
    closed trigger design, do you think that if you made that
    one change would that hypothetical device be as attrac-
    tive to surgeons?” A. “I don’t think so. I think the open
    trigger . . . was [surgeons’] preferred design.”).
    Similarly, the district court found significant the fact
    that Ethicon applied for utility patents that included
    figures similar to those of the claimed designs. Ethicon
    DCt, ECF No. 132, at 20. The district court noted that the
    utility patents described an “ergonomically formed”
    trigger with a proximal and distal portion having differ-
    ent lengths, a rounded button, and a fluted rotation knob.
    
    Id.
     at 20–21. Again, however, the district court’s analysis
    focuses on the concepts of an open trigger, button, and
    torque knob, rather than the specifically claimed design
    conceptions of those elements. Finally, the district court
    relied on Ethicon’s advertisements for its commercial
    product touting the “intuitive controls” of the rounded
    button and torque knob that offered the “ergonomic
    benefit of ‘minimal index finger repositioning’” and the
    “easy access” provided by the open trigger. Id. at 21.
    These advertisements, however, tout the functional
    benefits of the general design concepts of the underlying
    elements rather than any functional benefits of the specif-
    ic claimed designs.
    Ethicon’s Design Patents cover only the specific or-
    namental conceptions of the features shown in their
    figures, and not the general concepts of an open trigger, a
    rounded button, and a fluted torque knob oriented in
    some configuration as part of an ultrasonic surgical
    device. The analysis of whether Ethicon’s patented de-
    signs are invalid as dictated by function must also be
    performed at a level of particularity commensurate with
    34             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    the scope of the claims. For functionality purposes, “it is
    relevant whether functional considerations demand only
    this particular design or whether other designs could be
    used, such that the choice of design is made for primarily
    aesthetic, non-functional purposes.” Hupp, 
    122 F.3d at 1460
    . The district court performed its functionality
    analysis at too high a level of abstraction, focusing on the
    general concepts of an open trigger, torque knob, and
    activation button rather than the ornamental designs
    adorning those elements.
    Moreover, Covidien has not shown by clear and con-
    vincing evidence that no designs other than those claimed
    in the Design Patents allow the underlying ultrasonic
    shears to perform their intended function. Indeed, the
    evidence in the record leads to the opposite conclusion.
    We therefore conclude the district court clearly erred in
    finding that Ethicon’s patented designs are dictated by
    functional considerations and are therefore invalid as
    primarily functional. Because Covidien has not met its
    burden of showing that the Design Patents are invalid as
    functional, we reverse the district court’s grant of sum-
    mary judgment of invalidity of the Design Patents for
    functionality.
    2. Claim construction
    Because the Design Patents are not invalid, we move
    to the district court’s grant of Covidien’s motion for sum-
    mary judgment of noninfringement. The district court
    found the claimed trigger, torque knob, and activation
    button elements of the Design Patents to be “based on
    functional considerations.” Ethicon DCt, ECF No. 132, at
    23–24. The district court therefore construed each claim
    of the Design Patents to encompass “nothing,” factoring
    out and removing every element from the scope of the
    claimed designs. Id. at 24.
    We review the district court’s ultimate construction de
    novo, and any underlying factual findings supporting the
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.            35
    construction for clear error. Teva, 135 S. Ct. at 841.
    Because a claimed design is better represented by an
    illustration rather than a description, we have instructed
    that, unlike utility patents, “the preferable course ordi-
    narily will be for a district court not to attempt to ‘con-
    strue’ a design patent claim by providing a detailed verbal
    description of the claimed design.” Egyptian Goddess, 
    543 F.3d at 679
    . We have explained, however, that there are
    a number of claim scope issues which may benefit from
    verbal or written guidance, among them the distinction
    between features of the claimed design that are ornamen-
    tal and those that are purely functional. 
    Id. at 680
    .
    For purposes of validity, as discussed above in section
    II.C.1., a design patent is invalid if its overall appearance
    is dictated by function, and therefore primarily functional.
    L.A. Gear, 
    988 F.2d at 1123
    . If the overall appearance of
    a claimed design is not primarily functional, the design
    claim is not invalid, even if certain elements have func-
    tional purposes. Richardson, 
    597 F.3d at
    1293–94. The
    scope of that claim, however, must be limited to the
    ornamental aspects of the design, and does not extend to
    “the broader general design concept.” OddzOn Prods.,
    Inc. v. Just Toys, Inc., 
    122 F.3d 1396
    , 1405 (Fed. Cir.
    1997).
    Richardson involved a claim to the ornamental design
    of a multi-function carpentry tool that combined a ham-
    mer with a stud climbing tool and a crowbar. 
    597 F.3d at 1290
    . There was no dispute that several individual
    elements of the claimed design had functional purposes.
    In particular, a portion of the hammer head was flat to
    effectively deliver force to a struck object, the handle of
    the tool was elongated to provide leverage, the crowbar
    was at the end of the handle to reach into narrow spaces,
    and a jaw was located on the opposite end of the hammer
    head to allow the device to be used as a climbing step. 
    Id. at 1294
    . These elements—which composed the entirety of
    the multi-function tool—had utility that had been known
    36             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    and used in the art for more than a century, and were
    thus outside the scope of the design claim. 
    Id.
     This did
    not mean, however, that the design claim had no scope.
    Rather, the claim was limited to the ornamental aspects
    of these functional elements. In particular, the scope of
    the claim encompassed, among other ornamental aspects,
    the shape of the hammer head, the diamond-shaped flare
    of the crowbar and the top of the jaw, the rounded neck,
    the undecorated handle, and the orientation of the crow-
    bar relative to the head of the tool (which was not driven
    by functional considerations, unlike the orientation of the
    hammer head and crowbar at opposite ends of the han-
    dle). Apple Inc. v. Samsung Elecs. Co., 
    786 F.3d 983
    , 998
    (Fed. Cir. 2015) (discussing Richardson and citing Rich-
    ardson v. Stanley Works, Inc., 
    610 F. Supp. 2d 1046
    , 1050
    (D. Ariz. 2009)). Thus, the design claim did not broadly
    protect a multi-function tool with a hammer, crowbar,
    handle, and claw, but only the specific ornamental aspects
    of that tool in the depicted configuration.
    Similarly, in OddzOn, we limited the scope of a design
    claim to ornamental features of a football-shaped ball
    with a tail and fin structure, rejecting the patentee’s
    argument that its design claim covered the broad general
    concept of a ball with a “rocket-like” appearance. 122
    F.3d at 1405. We identified the “functional qualities” of
    the underlying article as its football shape combined with
    fins on a tail attached at one end of the ball, which added
    stability to the ball in the same manner as the tail and
    fins on darts or rockets. Id. Although the existence of a
    functional purpose for the football-shape, tail, and fin
    elements of the underlying article did not alone invalidate
    the design patent—as the claimed design also included
    some purely ornamental features—such functional as-
    pects at least necessitated cabining the scope of the
    design claim in order to prevent the claim from encom-
    passing the general design concept of a football with tails
    and fins. Id. (“[T]hese functional characteristics do not
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.           37
    invalidate the design patent, but merely limit the scope of
    the protected subject matter.”). Thus, we affirmed the
    construction of the district court, which removed the
    generalized football shape, tail, and fins from the scope of
    the claim, limiting the design claim to its purely orna-
    mental features: a “slender, straight tailshaft” and “three
    fins symmetrically arranged around the tailshaft,” each
    “gentl[y] curv[ing] up and outward [to] create[] a larger
    surface area at the end furthest from the ball” and
    “flar[ing] outwardly along the entire length of the tail-
    shaft” with the “fins seemingly protrud[ing] from the
    inside of the football.” Id. at 1400.
    Here, the district court found that the “U”-shaped
    trigger, the torque knob, and the rounded button claimed
    in various combinations by the Design Patents are dictat-
    ed by function. For example, the “U”-shaped trigger
    operates the clamping arm of the ultrasonic shears.
    Ethicon DCt, ECF No. 132, at 20. Its “open” design allows
    the user to exert higher input forces by employing multi-
    ple fingers, thus lessening hand fatigue and strain. Id.
    The torque knob and rounded button provide functional
    controls for the ultrasonic shears. Id. at 21. Their place-
    ment relative to the trigger offers ergonomic access, and
    the fluted shape of the torque knob permits a user to
    operate the knob with one finger. Id. We agree that the
    trigger, torque knob, and activation button elements of
    the underlying article have functional aspects. But the
    district court’s construction of the Design Patents to have
    no scope whatsoever fails to account for the particular
    ornamentation of the claimed design and departs from our
    established legal framework for interpreting design
    patent claims.
    As explained in greater detail in section II.C.3., for
    purposes of claim construction, the district court ignored
    the facts that the trigger has a particular curved design,
    the torque knob has a particular flat-front shape, and the
    activation button has a particular rounded appearance.
    38             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    Unlike the functionality inherent in the underlying arti-
    cles themselves, there is no evidence in the record, that
    any of the ornamental designs adorning those underlying
    articles are essential to the use of the article. See section
    II.C.1. Thus, although the Design Patents do not protect
    the general design concept of an open trigger, torque
    knob, and activation button in a particular configuration,
    they nevertheless have some scope—the particular orna-
    mental designs of those underlying elements. We there-
    fore vacate the district court’s construction that the
    Design Patents cover “nothing.” The scope of the Design
    Patents, although limited, encompasses the depicted
    ornamental aspects of certain combinations of the trigger,
    torque knob, and activation button elements of ultrasonic
    surgical shears, in specific relative positions and orienta-
    tions.
    3. Noninfringement
    Although the district court construed the claims of the
    Design Patents to have no scope, it performed, in the
    alternative, an infringement analysis of Covidien’s ac-
    cused ultrasonic shears based on a construction of the
    claimed designs that retained the ornamental aspects of
    the underlying trigger, torque knob, and activation button
    elements. Ethicon DCt, ECF No. 132, at 24, 26–34. We
    can thus evaluate the district court’s alternative grant of
    summary judgment of noninfringement of the Design
    Patents, because the district court apparently performed
    this analysis using a correct construction of the claimed
    designs.
    A design patent is infringed “[i]f, in the eye of an or-
    dinary observer, giving such attention as a purchaser
    usually gives, two designs are substantially the same, if
    the resemblance is such as to deceive such an observer,
    inducing him to purchase one supposing it to be the
    other.” Egyptian Goddess, 
    543 F.3d at 670
     (quoting
    Gorham Co. v. White, 
    81 U.S. 511
    , 528 (1871)). As with
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.           39
    utility patents, the patentee must prove infringement of a
    design patent by a preponderance of the evidence. 
    Id. at 679
    . Where the claimed and accused designs are “suffi-
    ciently distinct” and “plainly dissimilar,” the patentee
    fails to meet its burden of proving infringement as a
    matter of law. 
    Id. at 678
    . If the claimed and accused
    designs are not plainly dissimilar, the inquiry may benefit
    from comparing the claimed and accused designs with
    prior art to identify differences that are not noticeable in
    the abstract but would be significant to the hypothetical
    ordinary observer familiar with the prior art. 
    Id.
    Differences, however, must be evaluated in the con-
    text of the claimed design as a whole, and not in the
    context of separate elements in isolation. Where, as here,
    the claimed design includes several elements, the fact
    finder must apply the ordinary observer test by compar-
    ing similarities in overall designs, not similarities of
    ornamental features in isolation. Richardson, 
    597 F.3d at 1295
    ; Crocs, Inc. v. Int'l Trade Comm’n, 
    598 F.3d 1294
    ,
    1303–04 (Fed. Cir. 2010). An element-by-element com-
    parison, untethered from application of the ordinary
    observer inquiry to the overall design, is procedural error.
    Amini Innovation Corp. v. Anthony Cal., Inc., 
    439 F.3d 1365
    , 1372 (Fed. Cir. 2006).
    After performing a side-by-side comparison between
    the claimed designs and the design of Covidien’s accused
    shears, the district court concluded there could be no
    genuine dispute that the claimed and accused designs
    were plainly dissimilar because they “simply d[id] not
    look alike except for the fact that both are hand-held
    surgical devices with open trigger handles.” Ethicon DCt,
    ECF No. 132, at 26, 28. The district court thus deter-
    mined that even if the Design Patents had scope, the
    design of Covidien’s accused shears did not infringe any of
    the claimed designs. Id. at 27.
    The claimed and accused designs are depicted below:
    40              ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    D’804 patent, Fig. 1      Covidien’s accused product
    We agree with the district court that there is no genu-
    ine dispute the claimed and accused designs of an ultra-
    sonic surgical device are plainly dissimilar. On a general
    conceptual level, both designs include an open trigger, a
    small activation button, and a fluted torque knob in
    relatively similar positions within the underlying ultra-
    sonic device. Similarity at this conceptual level, however,
    is not sufficient to demonstrate infringement of the
    claimed designs. As discussed in section II.C.2., because
    each of these components has a functional aspect, the
    underlying elements must be excluded from the scope of
    the design claims at this general conceptual level. And
    when the remaining ornamental features of those compo-
    nents are compared, as a whole, to the corresponding
    ornamental features of Covidien’s accused ultrasonic
    surgical shears, the dissimilarities between the designs
    are plain.
    The district court identified the most obvious differ-
    ence between the claimed and accused designs as “the
    overall contoured shape” of the claimed design and the
    “overall linear shape” of the accused design. Id. The
    district court also identified plain dissimilarities between
    the ornamentation of the trigger, torque knob, and button
    elements of the claimed and accused designs. For the
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.           41
    trigger, the district court found dissimilarities between
    the proximal and distal portions of the claimed trigger
    handle, which curved toward and away from the device,
    respectively, and the proximal and distal portions of the
    accused trigger handle, which were parallel. Id. at 28.
    The district court also found differences between the
    width and length of the proximal and distal handles of the
    claimed and accused triggers, noting in particular that
    the proximal handle of claimed design was tapered at its
    end and at the portion connecting the proximal and distal
    handles, while the proximal handle of the accused design
    was a consistent width throughout. Id. at 29. For the
    activation button, the district court found the football-
    shaped button of the claimed design and the rectangular
    button of the accused design to be dissimilar. Id. at 31.
    As for the torque knob, the district court found dissimilar-
    ities between the unevenly-tapered flutes and flat front
    face with a large circular recess at its center of the
    claimed design, and the evenly-tapered flutes and round-
    ed front face with no recess of the accused design. Id. at
    32–33. We find no error with the district court’s determi-
    nation that the claimed and accused designs are plainly
    dissimilar.
    Ethicon does not challenge any of these specific find-
    ings by the district court, but instead asserts that the
    claimed and accused designs are not plainly dissimilar,
    and as a result, contends that the district court should
    have considered the frame of reference provided by the
    prior art, which Ethicon characterizes as predominantly
    featuring thumb-ring and loop-shaped triggers. However,
    comparing the claimed and accused designs with the prior
    art is beneficial only when the claimed and accused
    designs are not plainly dissimilar. Egyptian Goddess, 
    543 F.3d at 678
    . Because the district court found the nonfunc-
    tional, ornamental aspects of the claimed and accused
    designs to be plainly dissimilar, it did not need to compare
    the claimed and accused designs with the prior art, as
    42             ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    resolution of the infringement inquiry was already clear.
    
    Id.
     (“In some instances, the claimed and the accused
    design will be sufficiently distinct that it will be clear
    without more that the patentee has not met its burden of
    proving the two designs would appear ‘substantially the
    same’ to the ordinary observer.”).
    Ethicon also contends that the district court erred in
    identifying who the ordinary observer would be. The
    district court found the ordinary observer to be a sophisti-
    cated entity who managed the complex medical device
    purchasing process, because that entity was the ultimate
    purchaser of the underlying ultrasonic surgical shears.
    Ethicon DCt, ECF No.132, at 25. Ethicon argues that the
    ordinary observer is the surgeon who would use the
    shears.
    The Supreme Court explained in Gorham that the or-
    dinary observer is not an expert in the claimed designs,
    but one of “ordinary acuteness” who is a “principal pur-
    chaser[]” of the underlying articles with the claimed
    designs. 81 U.S. at 528; Arminak & Assocs., Inc. v. Saint-
    Gobain Calmar, Inc., 
    501 F.3d 1314
    , 1322–23 (Fed. Cir.
    2007) (overruled on other grounds by Egyptian Goddess).
    Ethicon does not dispute that it is the hospital or medical
    device supplier, not the surgeon, who is ultimately re-
    sponsible for purchasing the underlying articles at issue.
    Regardless, we see no need to resolve this dispute because
    Ethicon fails to explain how the infringement analysis
    would be affected if surgeons—who are more sophisticated
    than the general public—were considered to be the hypo-
    thetical ordinary observer. The claimed and accused
    designs are plainly dissimilar even to one less discerning
    than the ordinary observer; these distinctions would only
    be more evident to a sophisticated observer, whether a
    purchasing entity or a surgeon.
    As the district court correctly concluded, the scope of
    the Design Patents “do[es] not entitle [Ethicon] to pre-
    ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.           43
    clude others from using all styles or placements of open
    triggers, fluted rotation knobs, or activation buttons.”
    Ethicon DCt, ECF No. 132, at 26. Rather, because these
    elements have functional purposes, the Design Patents
    protect only the ornamental designs adorning those
    elements, and not the general concept of an ultrasonic
    surgical device having an open trigger, a fluted knob, and
    a rounded button. Here, there can be no genuine dispute
    that at the proper level of granularity, the claimed orna-
    mental designs of the Design Patents are, as a whole,
    plainly dissimilar from the ornamental design of
    Covidien’s accused ultrasonic shears.       Therefore, we
    affirm the district court’s grant of summary judgment of
    noninfringement of the Design Patents.
    ***
    We have considered the parties’ remaining arguments
    and find them unpersuasive.
    III. CONCLUSION
    Because one of ordinary skill in the art, in view of the
    specification, would understand the scope of the claims of
    the ’501 patent with reasonable certainty, we reverse the
    district court’s grant of summary judgment of invalidity of
    the ’501 patent for indefiniteness. We affirm the district
    court’s claim construction of the term “loosely contact” in
    claims 1 and 3 of the ’275 patent. We find, however, that
    disputed issues of material fact remain as to whether
    Covidien’s accused ultrasonic shears infringe the “config-
    ured to loosely contact” and “adapted to absorb undesired
    vibrations” limitations of the asserted claims. Thus, we
    vacate the district court’s grant of summary judgment of
    noninfringement of the asserted claims of the ’275 patent.
    Because Covidien has not met its burden of showing that
    the ornamental designs claimed by the Design Patents
    are primarily functional, we reverse the district court’s
    grant of summary judgment of invalidity of the Design
    Patents. We also vacate the district court’s construction
    44               ETHICON ENDO-SURGERY, INC.   v. COVIDIEN, INC.
    of the Design Patents as having no claim scope whatsoev-
    er. The ornamental designs claimed by the Design Pa-
    tents, however, are plainly dissimilar from the designs of
    Covidien’s accused ultrasonic shears. We thus affirm the
    district court’s alternative grant of summary judgment of
    noninfringement of the Design Patents. Finally, we
    remand to the district court for further proceedings relat-
    ing to the asserted claims of the ’501 patent and the ’275
    patent.
    AFFIRMED IN PART, REVERSED IN PART,
    VACATED IN PART, AND REMANDED
    COSTS
    No costs.
    

Document Info

Docket Number: 2014-1370

Citation Numbers: 796 F.3d 1312, 115 U.S.P.Q. 2d (BNA) 1880, 2015 U.S. App. LEXIS 13798, 2015 WL 4680726

Judges: Lourie, Bryson, Chen

Filed Date: 8/7/2015

Precedential Status: Precedential

Modified Date: 10/19/2024

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