Granted Patent
Utility
US 5,888,944 · App. 08/880,266
Oil-based drilling fluid
Inventor:
Arvind D. Patel
Patented Case
View Patent ↗
Granted: Mar 30, 1999
Filed: Jun 23, 1997
Inventor
Arvind D. Patel
Assignee (at issue)
M-I 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.