Granted Patent
Utility
US 4,880,067 · App. 07/156,831
Apparatus for drilling a curved borehole
Inventor:
Henk H. Jelsma
Patented Case
View Patent ↗
Granted: Nov 14, 1989
Filed: Nov 14, 1989
Inventor
Henk H. Jelsma
Assignee (at issue)
Baroid Technology, 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.