Speaking of the Patently-O patent law blog, let’s learn a little patent law. It’s been a while since law school.
The claims in a patent must be sufficiently definite so as to provide a standard by which a third party could, with some degree of certainty, determine whether a given practice would or would not be an infringement of the claims. 35 U.S.C. sec. 112. In other words, indefiniteness is just what it sounds like. But how fuzzy is fuzzy? In Fisher-Price v. Graco (Fed. Cir. 2005), the Federal Circuit ruled (in a “non-precedential” decision)
After a Markman hearing, the district court found several limitations of the claim indefinite (italicized) and thus invalid.
On appeal, the CAFC explained that a defect in a claim must be “severe” before it will be invalidated as indefinite. Here, the CAFC reversed because the “patent is not complex; it is readily understood by both the expert and layperson [and] the words used in the limitation are simple, with well-known ordinary meanings [that] can be construed without great difficulty, even if, as [the challenger] points out, it is not mentioned in the specification.
This is consistent with an August decision reported by Bill Heinze in which the Federal Circuit confirmed the rule that “When a claim ‘is not insolubly ambiguous, it is not invalid for indefiniteness.'”
I like this “insolubly ambiguous” standard because indefiniteness of patent claims makes me think — however inappositely (and I do think inappositely all the time) — of likelihood of confusion, thereby warming the otherwise bitterly cold cockles of my heart. More seriously: Wrting and prosecuting a patent all the way is serious business. Patent lawyers, whose malpractice premiums make them the ob-gyns of the legal profession,* need to be second-guessed in litigation like a headache. Setting the standard for indefiniteness high, and keeping it there, is a good idea.
* It is true that both bring marvelous things screaming into the world, is it not?