Granted Patent
Utility
US 4,078,611 · App. 05/739,128
High temperature perforating method
Inventor:
Roy R. Vann
Patented Case
View Patent ↗
Granted: Mar 14, 1978
Filed: Nov 5, 1976
Inventor
Roy R. Vann
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.