Narrow Construction Was Correct Where the Claim Was Ambiguous and a Broader Construction Was Inconsistent With the Invention's Sole Purpose

World Class Tech. Corp. v. Ormaco Corp., 769 F.3d 1120 (Fed. Cir. Oct. 20, 2014) (Prost, TARANTO, Hughes) (D. Or.: Acosta) (1 of 5 stars)

Federal Circuit affirms a stipulated judgment of noninfringement by affirming claim construction. The patent claimed an orthodontic bracket with a slot for holding a wire that exerts a corrective force on a tooth, a slide that moves across the slot to hold the wire in place (or release it), a "support surface" at an acute angle to the slot's base, and a separate ledge. The parties disputed whether the "support surface" had to support the slide through its entire movement across the slot.

The Federal Circuit concluded it did. The claim language was ambiguous, so "[i]n such circumstances, we turn to the specification." Slip op. at 7. The broader construction covered embodiments in which the acute angle formed by the support surface did not serve the "sole purpose" the patent identified for it—solving the prior art problem of contact between the slide and the gums. "Such a construction is unmoored from, rather than aligned with, the description of the invention." Id. at 8.Moreover, the patent tied the slide's movement to the support surface, which "strongly implies" the slide moves along only the support surface, and distinguished it from the ledge, suggesting that a broad construction that allowed the slide to move along either of them was wrong. Claim differentiation did not require a different result—there was still a difference in scope under the narrow construction, and the specification "precludes" any inference that the broader construction was right. Finally, a portion of the prosecution history was "not clear enough" to require a broader construction than the one "compelled by the specification." Id. at 11.