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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 = '425') AND (category.subclass = '441') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '425'; Subclass is '441';

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T / S Patent Date Description Patentee Category Assigned To
 1921
U 1,381,695 June 14, 1921 Porcelain Tube Heading Machine
Machine for making wall tubes		 BEATTY, Thomas W.
 Wall Tube  

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