Granted Patent
Utility
US 4,660,638 · App. 06/741,074
Downhole recorder for use in wells
Inventor:
Donald N. Yates, Jr.
Patented Case
View Patent ↗
Granted: Apr 28, 1987
Filed: Jun 4, 1985
Inventor
Donald N. Yates, Jr.
Assignee (at issue)
Halliburton
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.