Granted Patent
Utility
US 6,148,952 · App. 09/541,194
Hydraulic slotted cylinder source
Inventors:
Otis A. Johnston, Michael W. Norris
Patented Case
View Patent ↗
Granted: Nov 21, 2000
Filed: Apr 3, 2000
Inventors
Otis A. Johnston
Michael W. Norris
Assignee (at issue)
Western Atlas International, 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.