The term “about” should be given its ordinary and accepted meaning of “approximately” unless the patentee clearly redefines “about” in the specification. No more specific of an interpretation (e.g., a particular numerical range) is warranted by the use of this term alone.
Background / Facts: The patents being asserted here in response to a generic drug ANDA submission are directed to formulations of tranexamic acid, which is used to treat heavy menstrual bleeding, or menorrhagia, in women. To combat the gastrointestinal side effects of the immediate release version used abroad, the patents describe a modified-release formulation with certain specified dissolution rates, i.e., the rate at which the salt dissolves into water. In particular, the claims recite the amount of tranexamic acid released at specified times as being “less than about 70% by weight … at about 45 minutes.”
Issue(s): Whether the term “about” should be construed to demarcate a particular numerical range.
Holding(s): No. “‘About’ is not defined either explicitly or by implication by the specification. We think that the district court did not err in giving the term ‘about’ its ordinary meaning and in refusing to give it a more specific construction. … We affirm the district court’s construction of ‘about’ to mean ‘approximately,’ as well as its refusal to construe ‘about’ to represent a particular numerical error rate.”