SHIMANO, INC. v. REA (Fed. Cir. 2013) (NP) – Antecedent Basis in Claim Construction

Background / Facts: The patent on appeal from reexamination here is directed to changing the speed of a bicycle by altering the gear ratios in a gear-shifting mechanism. The claimed gear-shifting mechanism contains one or more rings that control “pawls.” Through a mechanism controlled by the bicycle rider, the pawls can be caused to engage multiple “sun gears.” In this regard, the portion of claim 1 in dispute recites “a speed-change controlling portion, comprising … at least two sets of pawls engageable with and releasable from the ratchet-teeth of the sun gears; [and] a pawl-controlling ring for controlling the position of the pawls.”

Issue(s): Whether the claimed device must contain a pawl-controlling ring that is capable of controlling the position of both sets of pawls (rather than just one of the sets).

Holding(s): Yes. The third-party requestor Shimano contended that “the pawls” referenced in the limitation reciting “a pawl-controlling ring for controlling the positions of the pawls” should be read to include “any subset of the ‘at least two sets of pawls’” (e.g., one set) referred to in the prior limitation (which is shown in the prior art). However, the court concluded that “[t]he reference to ‘the pawls’ in the limitation reciting a pawl-controlling ring is most naturally understood to refer back to the ‘at least two sets of pawls’ in the immediately preceding limitation,” i.e., all of the recited sets of pawls, not just one of the sets. “Moreover, that interpretation is supported by the description in the specification of the pawl-controlling ring ‘controlling the position of two or more sets of pawls.’”

Prosecution Takeaways: While somewhat context specific, the most natural reading of “at least two elements” followed by reference to “the elements” implies that the later reference refers to all of the earlier elements, not a subset thereof.

Full Opinion