Date: April 21, 2010
Re: Canon of consistent claim term interpretation
How do the courts use the canon of claim interpretation which states that a claim term should be interpreted consistently throughout the claims unless the specification and prosecution history indicate that the claim term has different meanings at different portions of the claims?
The courts generally give the same meaning to the same term in different portions of the claims, but this is a rebuttable presumption. The courts will sometimes construe the same term differently with just subtle evidence from the specification or prosecution history. There is some confusion as to whether the same term appearing in both an apparatus claim and a method claim should have a presumption of carrying the same definition.
I. Claim Construction Generally
Interpretation of claims and claim terms in a patent, called claim construction, is sometimes easily accomplished simply by applying common dictionary meaning to each of the words in a claim. Phillips v. AWH Corp., 415 F.3d 1303, 1314 (Fed. Cir. 2005) (en banc) (“In some cases, the ordinary meaning of claim language as understood by a person of skill in the art may be readily apparent even to lay judges, and claim construction in such cases involves little more than the application of the widely accepted meaning of commonly understood words.”) However, claim construction is often unclear, particularly as the inventor is allowed to be her own lexicographer. Shoenhaus v. Genesco, Inc., 440 F.3d 1354, 1358 (Fed. Cir. 2006) (“The patentee is free to act as his own lexicographer, and may set forth any special definitions of the claim terms in the patent specification or file history, either expressly or impliedly.”) The meaning of a claim is the interpretation that would be given it by a person of ordinary skill in the art. Phillips, 415 F.3d at 1313. To determine...