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SELECT DISTINCT patent.*, YEAR(date) as year FROM patent WHERE (category = 'U-186') ORDER BY date ASC, patent, type

Total of 1 patents found where: Category is 'U-186';

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T / S Patent Date Description Patentee Category Assigned To
 1917
U Specimen known 1,251,416 December 25, 1917 Insulator
U-186 (improved)		 PURKEY, Benjamin S.
 U-186  

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