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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 = '228') AND (category.subclass = '254') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '228'; Subclass is '254';

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T / S Patent Date Description Patentee Category Assigned To
 1937
U Specimen known 2,094,287 September 28, 1937 Method of Manufacturing Multipart Glass Articles
Method to manufacture multiple glass objects (blocks, insulators, etc.)		 ZIMMERMAN, Willard P.
HOLMES, Minot K.
 Method Owens-Illinois Glass Co.

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