Granted Patent
Utility
US 4,427,834 · App. 06/332,690
Dispersant-VI improver product
Inventor:
Michael K. Martin
Patented Case
View Patent ↗
Granted: Jan 24, 1984
Filed: Dec 21, 1981
Inventor
Michael K. Martin
Assignee (at issue)
SHELL OIL 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.