Granted Patent
Utility
US 4,589,979 · App. 06/768,530
Upgrading heavy gas oils
Inventors:
Sam Ferguson, Darrell D. Reese
Patented Case
View Patent ↗
Granted: May 20, 1986
Filed: Aug 22, 1985
Inventors
Sam Ferguson
Darrell D. Reese
Assignee (at issue)
Nalco Chemical 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.