The petitioner added and amended several claims during an ex parte reexamination of a patent directed to a drilling tool. The examiner applied a broad meaning to the claim term “body,” which appeared in several claims, and thus rejected those claims as anticipated by the prior art. The Patent Trial and Appeal Board (PTAB) agreed with the examiner’s broad interpretation of the term “body” as reasonable and affirmed rejection of the claims. The petitioner appealed to the Federal Circuit.

In affirming the examiner’s rejections, the PTAB determined that the term “body” is a “generic term such as ‘member’ or ‘element’ that by itself provides no structural specificity.” The PTAB reasoned that although “the specification describes the body as a discrete element separate from other elements,” the specification does not “define the term ‘body’” or “preclude the examiner’s interpretation.” The petitioner argued that one of ordinary skill in the art reading the specification would understand the term “body” to be a distinct element because the specification consistently refers to and depicts the “body” as separate from the other components.

The Federal Circuit concluded that the PTAB’s construction of “body” was unreasonably broad. The specification did not use the term “body” as a generic body, but instead consistently described and referred to the body as a component distinct from others. The correct inquiry in giving a claim term its broadest reasonable interpretation in light of the specification is one that corresponds with what and how the inventor describes his invention in the specification—i.e., an interpretation that is “consistent with the specification.” Even though the specification did not expressly define the term “body,” the term was used consistently enough that the patentee had acted as his own lexicographer because of the repeated and consistent descriptions in the specification. Because the anticipation rejection was based on an unreasonably broad construction of the term “body,” the rejections of those claims were reversed.