Federal Circuit Patent Watch: Use of ‘a’ vs. ‘the’ in claims


Precedential Federal Circuit Opinions

  1. EVOLUSION CONCEPTS, INC. v. HOC EVENTS, INC. [OPINION]  (2021-1963, 1/14/22) (Prost, Taranto, Chen)

    Taranto, J.  Reversing summary judgment of noninfringement for patent related to a firearm and remanding. An unasserted claim required removing “all parts of the factory installed magazine release button assembly” and installing “a magazine catch bar.” Defendant argued that use of the indefinite article “a” in the limitation “a magazine catch bar” meant that the installed magazine bar could not be the factory installed magazine bar that had been previously removed. The district court agreed, construed “a magazine catch bar” in the asserted claims as excluding factory installed catch bars and granted summary judgment of noninfringement based on that construction.  The Court disagreed. “Accepting [defendant’s] position would amount to reading additional limitations into [the unasserted claim] not required by its language. [The unasserted claim] requires only ‘removing’ a specific type of magazine catch bar (the one installed by the manufacturer) and then installing ‘a magazine catch bar.’ [citation omitted]. It does not require, as a removal step, ‘discarding’ the OEM catch bar. Nor does it require installing a ‘new’ or ‘different’ magazine catch bar. [Defendant] argues that the use of ‘a’ before ‘magazine catch bar,’ instead of antecedent-basis language such as ‘said’ or ‘the,’ means that the two magazine catch bars must be different. The use of antecedent-basis language like ‘said’ or ‘the,’ however, would have narrowed the term to cover only a factory installed magazine catch bar, and neither party advances that construction.”

DISCLAIMER: Because of the generality of this update, the information provided herein may not be applicable in all situations and should not be acted upon without specific legal advice based on particular situations.

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