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invention category A group or set of inventions that are classified together because of common characteristics. Invention groups that include Agricultural, Communications, Computing, Energy, Transportation and more.
Physical processes not more specifically provided for in other classes. (1) Note. Patents containing both a claim to an inorganic compound or non-metallic element, and a claim to a physical process for this class, are classified in Class 423, Chemistry of Inorganic Compounds, and cross-referenced here. (2) Note.