The claims are the most important part of any patent. They define what the patented invention is.1 Hence, the first step in determining whether a patent is valid or infringed is to analyze the claims and determine precisely what they mean. This analysis is known as claim construction or claim interpretation. Claims are written in the English language, but they often employ a technical vocabulary, the meaning of which is not immediately apparent. The following is an example of patent claim language, chosen more or less at random:
1. An aqueous cosmetic emulsion comprising: i) an isoparaffin: ii) a C8-C22 alkyl phosphate salt; wherein the isoparaffin and alkyl phosphate salt are present in a respective weight ratio of from about 40:1 to about 1:1, and said emulsion having a viscosity ranging from about 35 to about 90 Brookfield units as measured with a Brookfield Viscometer Model LTV using a #4 spindle rotating at 60 rpm at 25°C.2
The claim is for a hand lotion.
The obscurity of claim language can be traced to two sources. First, because patents are awarded to technological advancements, a technical vocabulary is often best suited to describe what the invention is. The language of the preceding example is probably meaningful to the chemist who invented the lotion and to other chemists who are likely to be reading the patent.
1 Alloc, Inc. v. International Trade Comm'n, 342 F.3d 1361, 1368 (Fed. Cir. 2003).
2 Conopco, Inc. v. May Dept. Stores Co., 46 F.3d 1556, 1560 (Fed. Cir. 1994).