Granted Patent
Utility
US 6,749,330 · App. 09/999,339
Cement mixing system for oil well cementing
Inventor:
Thomas E. Allen
Patented Case
View Patent ↗
Granted: Jun 15, 2004
Filed: Nov 1, 2001
Inventor
Thomas E. Allen
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.