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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 = '379') AND (category.subclass = '417') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '379'; Subclass is '417';

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T / S Patent Date Description Patentee Category Assigned To
 1886
U 343,014 June 1, 1886 Means for Preventing Disturbances on Telephone Lines
Pre-transposition technique to eliminate induced current on telephone and telegraph wires		 DANN, John E.
LAPP, John
 Transposition  

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