Granted Patent
Utility
US 5,439,032 · App. 08/294,372
Inflatable gas pipeline stopper with dual air bag
Inventor:
Joseph Petrone
Patented Case
View Patent ↗
Granted: Aug 8, 1995
Filed: Aug 23, 1994
Inventor
Joseph Petrone
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.