Granted Patent
Utility
US 4,902,167 · App. 07/318,627
Land fill for waste materials and method of making the same
Inventor:
Paul Shelton
Patented Case
View Patent ↗
Granted: Feb 20, 1990
Filed: Mar 3, 1989
Inventor
Paul Shelton
Assignee (at issue)
American Colloid Company
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.