• Acumed LLC v. Stryker Corp.
  • April 17, 2007 | Author: Lawrence M. Sung
  • Law Firm: Nixon Peabody LLP - Washington Office
  • On April 12, 2007, the Federal Circuit affirmed the district court’s judgment that Stryker willfully infringed U.S. Patent No. 5,472,444, which related to an orthopedic nail for treating humeral fractures, but vacated and remanded the permanent injunction. The Federal Circuit stated:

    The [parties] dispute [the] claim requirement of a “curved shank,” construed by the district court to mean a shank that “has a bend or deviation from a straight line without sharp corners or sharp angles.” [A] court must begin by “look[ing] to the words of the claims themselves . . . to define the scope of the patented invention.” The task of comprehending those words is not always a difficult one. “In some cases, the ordinary meaning of claim language as understood by a person of skill in the art may be readily apparent even to lay judges, and claim construction in such cases involves little more than the application of the widely accepted meaning of commonly understood words.” “[C]urved,” as it is used in the ‘444 patent, is not a “term[] that ha[s] a particular meaning in a field of art.” Its ordinary meaning encompasses “curvature” made up of small discontinuities. Consider, for instance, an archway made from rectangular bricks. The bricks are at angles with respect to each other, but the overall effect is to describe an arc. It would be unreasonable to say that such an archway is not “curved.” If the word “curved” is given its ordinary, lay meaning, the district court’s construction is correct.

    [Stryker] argues that the district court’s exclusion of “sharp corners or sharp angles” renders the construction insufficiently definite, since the court did not specify precisely how “sharp” is too sharp. However, a sound claim construction need not always purge every shred of ambiguity. The resolution of some line-drawing problems—especially easy ones like this one—is properly left to the trier of fact. Here, the accused product has a rounded-off six-degree angle in its shaft. A reasonable jury could have found that in the context of this sort of nail, a rounded bend of six degrees was not a “sharp angle.” The jury’s conclusion is bolstered by the testimony of Stryker’s own technical expert, who noted in reference to the Stryker nail that “there’s no sharp angle there.” There may be some area of imprecision within the district court’s “without sharp angles” construction, but this accused product is in no danger of falling within that area. The construction is correct, and the jury’s finding that the Stryker nail possesses a “curved shank” is supported by substantial evidence. . . .

    The district court defined “transverse holes” as “holes across the butt portion of the nail.” Stryker argues that this claim term should be limited to holes that are perpendicular to the nail shaft, excluding from the claim scope holes that are tilted so that one end of the hole is vertically offset from the other end [because] “[e]very description of the transverse holes in the ‘444 patent contemplates a perpendicular hole.” This is a correct characterization of the patent: every figure which illustrates the holes shows them going perpendicularly through the shaft, and the written description characterizes the holes in Figure 2 as “perpendicular to the portion of the nail axis at the butt portion 14 of the nail.” However, Figure 2 and the text characterizing it simply discloses a single, preferred embodiment of the invention. “[A]lthough the specification often describes very specific embodiments of the invention, we have repeatedly warned against confining the claims to those embodiments.” . . .

    The dissent states that the specification language which discloses only perpendicular holes should be determinative of the claim scope. [W]hile the dissent emphasizes the fact that there are three references to “perpendicular” holes in the specification, its argument is ultimately premised on characteristics which the patentee has attributed to a single preferred embodiment. . . . By highlighting the specification phrase “each of which is defined” and by describing that phrase as “important[],” the dissent appears to suggest that the patentee has in some sense imposed a limiting definition upon the word “transverse.” But the use of the word “defined” here does not imply a lexicographic definition, especially not a definition of “transverse” to mean “perpendicular.” Instead, the statement that the holes of the cited embodiment are “defined on . . . an axis” merely introduces the useful abstract concept of a “hole axis,” later employed in the claims to describe the orientation of the holes with respect to each other. The claims repeatedly echo this form of usage of the word “define.” If the word “define” were always to be an important signifier of limitation, this claim language would indicate that the butt portion has been defined to be transverse holes, that those holes in turn have been defined as hole axes, and that the curved portion and butt portion—physical parts of the nail—have each been dubbed identical to an imaginary central axis. These interpretations are incorrect, but they are the natural consequence of finding a restrictive definition of a term anywhere the word “define” might appear in this patent, regardless of context. The specification does not define “transverse” and “perpendicular” to be coequal in meaning.