Opinion ID: 625315
Heading Depth: 1
Heading Rank: 6

Heading: magnetic member

Text: The defendants argue that the district court correctly concluded that the term magnetic member in amended claim 23 means a permanent magnet. Aspex disagrees and argues that the term refers either to a magnet or to a ferromagnetic member, i.e., a substance that is affected by a magnetic field. We agree with Aspex. The dispositive argument in favor of Aspex's construction is one of claim differentiation. New claim 35 is dependent from amended claim 23; the sole distinction between the two is that in new claim 35, the magnetic members of the auxiliary spectacle frame are magnets. If magnetic member meant magnet, new claim 35 would be entirely duplicative of amended claim 23. That result would be at odds with the ordinary principles of claim differentiation, as the presence of a dependent claim that adds a particular limitation gives rise to a presumption that the limitation in question is not present in the independent claim. Phillips v. AWH Corp., 415 F.3d 1303, 1315 (Fed.Cir.2005) (en banc). The defendants offer no reason not to apply that rule of claim differentiation in this case. We therefore hold that the term magnetic member in amended claim 23 must be construed not to be limited to a permanent magnet, but to include ferromagnetic materials as well.