Granted Patent
Utility
US 4,761,889 · App. 06/905,979
Method for the detection and correction of magnetic interference in the surveying of boreholes
Inventors:
Martin E. Cobern, Frederick A. Stone, Edmund M. Hamlin
Patented Case
View Patent ↗
Granted: Aug 9, 1988
Filed: Sep 10, 1986
Inventors
Martin E. Cobern
Frederick A. Stone
Edmund M. Hamlin
Assignee (at issue)
Teleco Oilfield Services 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.