Granted Patent
Utility
US 6,273,201 · App. 09/505,640
Pneumatic ground piercing tool with movable chisel head
Inventors:
Mark D. Randa, Steven W. Wentworth, Robert F. Crane
Patented Case
View Patent ↗
Granted: Aug 14, 2001
Filed: Feb 16, 2000
Inventors
Mark D. Randa
Steven W. Wentworth
Robert F. Crane
Assignee (at issue)
Earth Tool Company 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.