The U.S. Court of Appeals for the Federal Circuit has now held that a claim is not indefinite under 35 U.S.C. § 112, ¶ 2, even where a claim element lacks antecedent basis, if one of ordinary skill in the art could reasonably discern the meaning of the claim element, even though discerning the meaning may be difficult. Energizer Holdings, Inc. v. International Trade Comm’n, Case No. 05-1018 (Fed. Cir. Jan. 25, 2006) (Newman, J.).
Energizer Holdings had accused several respondents of violations of section 337 of the Tariff Act of 1930 based on alleged infringement of its patent, which is directed to zero-mercury-added alkaline batteries. Energizer asserted the respondents infringed certain claims that recite " … an anode gel comprised of zinc as the active anode component . . . and said zinc anode has a gel expansion of less than 25% after being discharged for 161 minutes to 15% depth of discharge at 2.88A." The International Trade Commission (ITC) held the claims invalid because "said zinc anode" lacked antecedent basis, and the claimed test parameters were imprecise. Energizer appealed.
The Federal Circuit reversed, stating that the definiteness "focuses on whether those skilled in the art would understand the scope of the claim when the claim is read in light of the rest of the specification." The Federal Circuit acknowledged that the ITC and the courts cannot redraft the claims to correct material errors, but if one of ordinary skill in the art would reasonably understand the claim, then the claim is not indefinite by virtue of its departing from the "antecedent basis" rule, which is a patent drafting rule administered during examination.
Neither the ITC nor the intervenors argued they did not understand the claim due to the absent antecedent basis. The Federal Circuit found that a claim that is amenable to construction is not indefinite, even if the task of construing the claim is difficult. The Court determined the claim at issue could be construed, and the antecedent basis was present by implication.
Practice Note
The Federal Circuit did not deal specifically with the ITC’s assertion that the claim was indefinite due to imprecise test parameters. In any event, when analyzing a claim for indefiniteness, that analysis must include consideration of whether one of ordinary skill in the art could determine the meaning of the claim, regardless of any difficulty in doing so.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.
