Nolo's Plain-English Law Dictionary

Statutory Subject Matter

A requirement for utility patent rights. To qualify, an invention must fit into at least one of five categories: compositions of matter (compounds such as a drug or glue); articles of manufacture (simple devices such as screwdrivers and rakes); machines (devices with moving parts, such as an auto engine); processes (a method of doing something such as an implant procedure); and new and useful improvements of any of the above categories.
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