This CLE webinar will guide patent counsel on the use of small words in patent claims. The panel will address the potential dangers of small words and the practical impact of recent court and PTAB decisions. The panel will offer best practices for preparing and prosecuting a U.S. patent application to avoid problematic claim terminology and troublesome language in the specification.
In a recent precedential decision, Enviro Tech Chemical Services v. Safe Foods Corp. (Fed. Cir. May 4, 2026), the Federal Circuit concluded that the term "about" was indefinite, which rendered all of the asserted claims invalid. Although terms of degree like "about" are not inherently indefinite, the Federal Circuit agreed with the district court that the intrinsic evidence failed to inform a skilled artisan of the term's scope with reasonable certainty.
Other small words such as "a," "the," "or," and "to" have also proven problematic for patent owners. For example, courts have sometimes held that "a" means "at least one" [see KCJ Corp. v. Kinetic Concepts Inc., 223 F.3d 1351 (Fed. Cir. 2000) and Baldwin Graphic Sys. Inc. v. Siebert Inc., 512 F.3d 1338 (Fed. Cir. 2008)], and in others have restricted it to mean "one and only one" [see Harari v. Lee, 656 F.3d 1331 (Fed. Cir. 2011) and Insituform Techs. Inc. v. CAT Contr. Inc., 99 F.3d 1098, 1106 (Fed. Cir. 1996)].
Highlighting the critical importance of word selection, the Federal Circuit has noted that, in view of claim construction's significance to issues of patentability, validity, and infringement, it is the patentee's responsibility to avoid textual sloppiness and resolve ambiguity. As such, a patent drafter's selection of even the smallest of words can significantly impact how a claim is construed—the more care taken in patent drafting and prosecution, the more likely the patent will be construed as the patentee desires and avoid these problems.
Listen as our authoritative panel of patent attorneys explains how "about," "a," and other small words can be dangerous for patent owners. The panel will discuss Enviro Tech and other recent district court and PTAB decisions, analyzing their practical impact on U.S. patent practice. The panel will also offer best practice tips for preparing and prosecuting a U.S. patent application to avoid such problematic claim terminology and troublesome language in the specification.
