U.S. patent law[]
The preamble to one or more patent claims is generally a short introductory phrase to frame the context of the claim. The purpose of the preamble is to
| “ | indicate the statutory class of the claim (often by implication from the words in the preamble) and to name or define the thing that is to be claimed.[1] | ” |
Most patent applications contain more than one claim. If some of the claims are directed to different statutory classes of invention, the preambles of the claims to each statutory class will be different.[2]