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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.
Certain important segments of the metal fabricating industries are classified in other major groups, such as machinery in Major Groups 35 and 36; transportation equipment, including tanks, in Major Group 37; professional scientific and controlling instruments, watches, and clocks in Major Group 38; and jewelry and silverware in Major Group 39.