Granted Patent
Utility
US 5,149,823 · App. 07/564,528
Sulfonamide substituted spirodilactams
Inventor:
Pen-Chung Wang
Patented Case
View Patent ↗
Granted: Sep 22, 1992
Filed: Aug 9, 1990
Inventor
Pen-Chung Wang
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.