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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 = '427') AND (category.subclass = '343') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '427'; Subclass is '343';

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T / S Patent Date Description Patentee Category Assigned To
 1935
U 1,987,683 January 15, 1935 Insulator
RFI: coat crown with copper glaze to prevent AM radio interference		 HUNT, Marsden H.
BARROW, George M.
 RFI Westinghouse Electric & Mfg. Co.

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