Granted Patent
Utility
US 5,909,779 · App. 09/108,025
Oil-based drilling fluids suitable for drilling in the presence of acidic gases
Inventors:
Arvind D. Patel, Jayanti Patel, Harris A Oehler
Patented Case
View Patent ↗
Granted: Jun 8, 1999
Filed: Jun 30, 1998
Inventors
Arvind D. Patel
Jayanti Patel
Harris A Oehler
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.