Patent claims are usually in the form of a series of numbered expressions, or more precisely noun phrases, following the description of the invention in a patent or patent application, and define, in technical terms, the extent of the protection conferred by a patent or by a patent application. They are of the utmost importance both during prosecution and litigation.
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a claim that refers back to (depends on) and further limits a preceding
dependent or independent claim. A dependent claim shall include every limitation of the claim from which it depends.