Granted Patent
Utility
US 4,375,237 · App. 05/879,968
Well equipment setting or retrieval tool
Inventor:
Ronald K. Churchman
Patented Case
View Patent ↗
Granted: Mar 1, 1983
Filed: Feb 21, 1978
Inventor
Ronald K. Churchman
Assignee (at issue)
Otis Engineering Corporation
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.