Granted Patent
Utility
US 4,903,992 · App. 07/338,283
Locking ring for oil well tool
Inventors:
Charles E. Jennings, L. Steven Landriault
Patented Case
View Patent ↗
Granted: Feb 27, 1990
Filed: Apr 14, 1989
Inventors
Charles E. Jennings
L. Steven Landriault
Assignee (at issue)
Vetco Gray, LLC
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.