If you are reading this, then some twist of fate has created a compelling need for you to become acquainted with one of the fundamental concepts in U.S. patent law, namely patent claims. Welcome, patent newbie! For most lay people, patent law is like a giant loaf of dry white toast. And, newbie, you’re about to consume a few slices of that dry white toast. Bon appetite!
A more helpful (but less amusing) metaphor is a fence, namely a physical structure often used to mark the perimeter of a person’s plot of land. Claims are the part of a patent which defines the scope of protection which the patent provides for an invention. The land enclosed by a fence is land from which the land owner can exclude the presence of others (would-be trespassers). Subject matter that falls within (or is enclosed by) the scope of a patent’s claims is subject matter which the patent owner can exclude others from making, using and/or selling. Hence, a patent claim is like a fence.
Constructing a fence to enclose the plot of land is analogous to preparing, filing and then prosecuting a patent application. The land itself is like the specification of the patent application. A map of the land is like the drawings of the patent application. Patents typically include multiple claims of varying scope. Such claims are like nested fences.
If you hunger for more dry white toast, an expanded version of this discussion can be found at this link. The expanded version explores the fence-analogy via a detailed, hypothetical example set in the late 1880′s in the USA, during the era of the “land rush” (or “land run”).