Granted Patent
Utility
US 4,438,816 · App. 06/378,024
Process for recovery of hydrocarbons from oil shale
Inventors:
Peter Urban, Russell W. Johnson, Lee Hilfman
Patented Case
View Patent ↗
Granted: Mar 27, 1984
Filed: May 13, 1982
Inventors
Peter Urban
Russell W. Johnson
Lee Hilfman
Assignee (at issue)
UOP LLC
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.