Granted Patent
Utility
US 5,458,197 · App. 08/148,736
Well cleanout system and method
Inventor:
Albert F. Chan
Patented Case
View Patent ↗
Granted: Oct 17, 1995
Filed: Nov 5, 1993
Inventor
Albert F. Chan
Assignee (at issue)
Atlantic Richfield 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.