Granted Patent
Utility
US 6,390,208 · App. 09/320,375
Aphron-containing well drilling and servicing fluids
Inventor:
Tommy F. Brookey
Patented Case
View Patent ↗
Granted: May 21, 2002
Filed: May 7, 1999
Inventor
Tommy F. Brookey
Assignee (at issue)
Masi Technologies, L.L.C.
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.