Patent Claim

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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Defines in words the boundaries of the invention so that the public will know what the invention is and can avoid infringing it.