Granted Patent
Utility
US 4,497,318 · App. 06/366,913
Esophageal obturator airway
Inventor:
T. Anthony DonMichael
Patented Case
View Patent ↗
Granted: Feb 5, 1985
Filed: Apr 9, 1982
Inventor
T. Anthony DonMichael
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.