A "working lumen" must be capable of working

The PTAB reversed the examiner in Ex parte Saadat wherein the case turned on the meaning of "working lumen."

Noting the law that

a claim element cannot be interpreted so broadly so as to read the limitation out of the claim. See Texas Instr. Inc. v. United States Int’l Trade Comm’n, 988 F.2d 1165, 1171 (Fed. Cir. 1993) (Claim language cannot be mere surplusage. An express limitation cannot be read out of the claim). Further, claim terms are not interpreted in a vacuum, devoid of the context of the claim as a whole.

the Board reversed the Examiner, observing

The evidence of record fails to establish that a “working” camera fixed within the interior of a device assembly (FF2) would have been understood by a person of ordinary skill in the art to be a “working lumen” (see, e.g., Ans. 11). Rather, a broadest reasonable interpretation of the phrase “working lumen” in light of the Specification is consistent with the Appellants‟ view that a “working lumen” is a lumen capable of facilitating the passage of tools (FF1; see also, App. Br. 13). An occupied channel or cavity would not be capable of this function.