Granted Patent
Utility
US 5,947,443 · App. 08/947,549
Plug valve
Inventors:
Thomas R. Shellenbarger, Charles J. Glover
Patented Case
View Patent ↗
Granted: Sep 7, 1999
Filed: Oct 11, 1997
Inventors
Thomas R. Shellenbarger
Charles J. Glover
Assignee (at issue)
Dresser Industries, 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.