Granted Patent
Utility
US 4,405,438 · App. 06/336,262
Process for recovery of different weight fractions of oil from shale
Inventors:
Bobby P. Faulkner, Michael H. Weinecke
Patented Case
View Patent ↗
Granted: Sep 20, 1983
Filed: Dec 31, 1981
Inventors
Bobby P. Faulkner
Michael H. Weinecke
Assignee (at issue)
Allis-Chalmers Corporation
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.