A stated purpose of the invention may be used to construe otherwise ambiguous claim language. Here, for example, an orthodontic device “support surface” was interpreted as being required to provide a particular type of support (during movement of a slide) in order to achieve the targeted gum avoidance. It may therefore be best to avoid overemphasizing a particular purpose of the invention if not all embodiments achieve it.
Background / Facts: The patent being asserted here is directed to a bracket for orthodontic braces that avoids or reduces interference with the gums even when being mounted on a molar tooth. The claims recite a “support surface” for engaging one portion of a movable member (slide) when it is in the closed position, but do not specify the interaction between the surface and the slide during the mounting process. On its face, the claim language is therefore broad enough to cover two arrangements, one (shown in the figures and designed to reduce the targeted gum interference) where the slide moves along the support surface and another (not shown or described in the patent) where the slide would move along an opposing ledge.
Issue(s): Whether the specification requires a claim interpretation where the support surface plays a slide-supporting role as the slide moves along its (angled) path into the closed position.
Holding(s): Yes. “Critically, the specification in this case identifies gum avoidance as the sole purpose of the acute angle the support surface must make with the slot base. [] Under [the patentee’s broader] construction, however, the acute angle would not serve the sole stated purpose in the arrangement that [the] construction is aimed at covering—in which the slide is inserted from the top, first moves along the ledge, and arrives at the support surface for closing after crossing the slot. In that embodiment, there is no problem of gum contact and no need for the acute angle. Such a construction is unmoored from, rather than aligned with, the description of the invention.”