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

Total of 1 patents found where: Category is 'Signal';

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T / S Patent Date Description Patentee Category Assigned To
 1911
U 1,003,143 September 12, 1911 Electric Signaling Apparatus
Improved signaling of railways		 LOCKE, Louis P.
 Signal  

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