It is Presumed That / the Preferred Embodiment / is Coverd by Claims

Accent Packaging, Inc, v. Leggett & Platt, Inc., [2012-1011] (February 4, 2013) [Rader, PROST and Reyna] The Federal Circuit reversed summary judgment of non-infringement of U.S. Patent No. 7,373,877, remanding with instructions to enter summary judgment of infringement.
DISCUSSION: The asserted claims of the '877 patent related to a a wire tier that used to bale recyclables and other waste into bundles. The claim language at issue was:

said operator assembly including a pivotal shaft assembly and elongated operator bodies, with each of the operator bodies being operably coupled with a respective one of said gripper, knotter, citing element and cover so as to supply driving power form the single drive assembly thereto.

Leggett & Platt argued that the claim language required that each elongate operator bodies be operably coupled with one and only one of the listed elements of the device. Such a construction would not cover Legget & Platt's device, where its elongate operator bodies were each coupled to two elements. The problem for Leggett & Platt was that this construction also did not cover the single disclosed embodiment in the '877 patent. Noting that "a claim interpretation that excludes a preferred embodiment from the scope of the claim is rarely, if ever, correct". The Federal Circuit said that it was not persuaded that the claim language required a different construction. The Federal Circuit said that  the use of the indefinite article "a", which is generally open to one or more. Further the specification substantiates a construct that allows for an elongated operator element to be operatively coupled to one or more operator elements, noting that in the only disclosed embodiment two elongated operator bodies are each coupled to two distinct operator elements.