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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 = '411') AND (category.subclass = '427') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '411'; Subclass is '427';

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T / S Patent Date Description Patentee Category Assigned To
 1880
U 234,523 November 16, 1880 Telegraph Insulator
Slotted circular insulator held by split metal screw bracket		 BIGEON, Charles
 Slotted  

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