This post was first published on July 16, 2014.
It would have been very well drummed into a patent professional, Mr. X, who has just started drafting a patent specification that “claims form the heart of a patent application,” or the “name of the game is claim,” and so on. Very few might agree with me if Mr. X has been told to carefully consider the words and/or features and/or the language used in the preamble, as improper drafting of preamble may limit the scope. Well, it is not Mr. X’s fault, nor the trainer’s fault. There are not many case laws or rather widely discussed case laws, elucidating or interpreting in detail the importance of a preamble as there are for definiteness, written description and other statutory requirements. In fact, in 1934 (in In Re Wolf), CCPA held that, “The preamble of a claim is introductory only and should not be considered as a limitation of the subject issue.”
While CCPA’s decision in In re Wolf is still held aloft like a banner, for more of a visual than cognitive effect, there are some case laws in which the federal circuit has touched upon or at certain times went into a little more detail on the importance/interpretation of preamble.