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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 = '313') AND (category.subclass = '250') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '313'; Subclass is '250';

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T / S Patent Date Description Patentee Category Assigned To
 1918
U 1,283,651 November 5, 1918 Lightning Arrester
Lightning arrester with hole through top of insulator similar to U-70.		 BUCHANAN, Sutton R.
 Lightning Arrester/U-70  

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