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SELECT DISTINCT patent.*, YEAR(date) as year FROM patent LEFT JOIN category ON category.patent = patent.patent AND category.type = patent.type WHERE (category.class = '420') ORDER BY date ASC, patent, type

Total of 2 patents found where: Class is '420';

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T / S Patent Date Description Patentee Category Assigned To
 1850
U 7,008 January 8, 1850 Improvement in Alloys for Points of Lightning Rods
Alloy composed of tin, antimony, bismuth, silver, platinum, and silex
SPRATT, James
Lightning Rod Point  
 1950
U 2,513,958 July 4, 1950 Electric Insulating Bushing and Glass Therefore
Glass capacitor bushing and improved seal with metal parts
OMLEY, Herbert A.
Bushing General Electric Co.

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