The district court had granted summary judgment to the defendants for non-infringement and prosecution estoppel in narrowing claim scope. Free Motion appealed.

In construing the claims we follow our recent decision in Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005) (en banc).

The district court’s grant of summary judgment of non-infringement rests on a finding that several claim limitations were not met in the accused devices. As to each of these we conclude that the district court erred.

There was confusion regarding the ordinals 'first' and 'second', which are nominally used as associative denotations, as in this case, but which the district court somehow construed as indicating location of certain parts on the exercise machine.

“First” does not denote spatial location, that is, it does not suggest where on the “first extension arm” or the “second extension arm” the pivot points are located. The correct construction of the word “first” merely associates the first pivot point with the first extension arm, and thus does not support the district court’s judgment that the accused devices do not infringe.

Next was the word "adjacent", to which a dictionary definition was sought, as "there is no suggestion here that intrinsic evidence defines the term or that the term adjacent has a specialized meaning in the relevant art."

The bottom line in using dictionaries for claim construction definition:

"The court must ensure that any reliance on dictionaries accords with the intrinsic evidence:...the task is to scrutinize the intrinsic evidence in order to determine the most appropriate definition. [That] does not mean that the term will presumptively receive its broadest dictionary definition or the aggregate of multiple dictionary definitions."

The specification thus suggests that “adjacent” simply means “not distant.” Indeed, Nautilus and Cybex appeared to agree before the district court that adjacent means “near.” (J.A. at 682, 2392, 2395.) Under this definition the district court’s judgment of non-infringement is not supported because the pivot points of the accused devices are not distant from the resistance assembly.

Then there's "a", which may, in claim construction, indicate singular or plural, unless the patentee restricts scope.

“‘[A]’ or ‘an’ in patent parlance carries the meaning of ‘one or more’ in open-ended claims containing the transitional phrase ‘comprising.’” KCJ Corp. v. Kinetic Concepts, Inc., 223 F.3d 1351, 1356 (Fed. Cir. 2000). This convention is overcome only when “the claim is specific as to the number of elements” or “when the patentee evinces a clear intent to . . . limit the article.” Id.

The references to a single cable in the specification are found in the description of the preferred embodiments, and do not evince a clear intent by the patentee to limit the article to the singular. RF Del., Inc. v. Pac. Keystone Techs., Inc., 326 F.3d 1255, 1263 (Fed. Cir. 2003) (“[W]hen a claim term is expressed in general descriptive words, it typically will not be limited to a numerical range that may appear in the written description as referring to a preferred embodiment or in other, narrower claims.”); Renishaw, 158 F.3d at 1248 (reciting the familiar maxim that “one may not read a limitation into a claim from the written description”).

Another indication is claim differentiation, where a narrowing dependent claim is indicative that an independent claim was intended broader in scope.

The doctrine of claim differentiation “create[s] a presumption that each claim in a patent has a different scope.” Comark Communications, Inc. v. Harris Corp., 156 F.3d 1182, 1187 (Fed. Cir. 1998). The difference in meaning and scope between claims is presumed to be significant “[t]o the extent that the absence of such difference in meaning and scope would make a claim superfluous.” Tandon Corp. v. United States Int’l Trade Comm’n, 831 F.2d 1017, 1023 (Fed. Cir. 1987). Here, dependent claims limiting the claim to a single cable confirm that the independent claims may encompass more than one cable.

In the finale, the CAFC affirmed the openness of the ubiquitous claim term "comprising".

The addition of unclaimed elements does not typically defeat infringement when a patent uses an open transitional phrase such as “comprising.” Crystal Semiconductor Corp. v. Tritech Microelectronics Int’l, Inc., 246 F.3d 1336, 1348 (Fed. Cir. 2001) (“In the parlance of patent law, the transition ‘comprising’ creates a presumption that the recited elements are only a part of the device, that the claim does not exclude additional, unrecited elements.”). That is essentially what the district court did here under the guise of construing the claims.

The presence of an undesirable prior art feature in addition to the elements recited in the claim, even when the undesirability of that feature formed the basis of an amendment and argument overcoming a rejection during prosecution, does not limit the claim unless there is a clear and unmistakable disclaimer of claim scope. Here, there is no such disclaimer. The “comprising” language allows additional features. The disclaimer, if there was one, only applied to the “claimed assembly,” not unclaimed features added to the patented device.

Remanded.