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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 = '52') AND (category.subclass = '307') ORDER BY date ASC, patent, type

Total of 3 patents found where: Class is '52'; Subclass is '307';

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T / S Patent Date Description Patentee Category Assigned To
 1938
U 2,107,994 February 8, 1938 Hollow Glass Building Block
Blocks with colored sheets placed inside
HAZELTON, Benjamin F.
OI Owens-Illinois Glass Co.
U 2,110,900 March 15, 1938 Building Block
Aluminum welding of blocks with aluminum foil
ZIMMERMAN, Willard P.
HOLMES, Minot K.
OI Owens-Illinois Glass Co.
 1940
U 2,196,109 April 2, 1940 Hollow Glass Building Block
Blocks with wire glass
EASTUS, Harold L.
OI Owens-Illinois Glass Co.

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