Granted Patent
Utility
US 4,390,416 · App. 06/327,996
Catalytic cracking of hydrocarbons
Inventors:
Ronald E. Ritter, Donald S. Henderson
Patented Case
View Patent ↗
Granted: Jun 28, 1983
Filed: Dec 7, 1981
Inventors
Ronald E. Ritter
Donald S. Henderson
Assignee (at issue)
W. R. Grace & Co.
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.