Granted Patent
Utility
US 4,418,756 · App. 06/299,931
Method and apparatus for performing operations in well tubing
Inventors:
John H. Yonker, Henry P. Arendt
Patented Case
View Patent ↗
Granted: Dec 6, 1983
Filed: Sep 8, 1981
Inventors
John H. Yonker
Henry P. Arendt
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.