Granted Patent
Utility
US 6,602,421 · App. 09/346,174
Method for purifying contaminated groundwater using steel slag
Inventor:
James S. Smith
Patented Case
View Patent ↗
Granted: Aug 5, 2003
Filed: Jul 1, 1999
Inventor
James S. Smith
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.