Granted Patent
Utility
US 5,881,826 · App. 08/800,727
Aphron-containing well drilling and servicing fluids
Inventor:
Tommy F. Brookey
Patented Case
View Patent ↗
Granted: Mar 16, 1999
Filed: Feb 13, 1997
Inventor
Tommy F. Brookey
Assignee (at issue)
Actisystems, Inc.
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.