Granted Patent
Utility
US 6,827,162 · App. 10/283,580
Self-retaining downhole-hammer drill bit
Inventor:
Brandon William Fisher
Patented Case
View Patent ↗
Granted: Dec 7, 2004
Filed: Oct 30, 2002
Inventor
Brandon William Fisher
Assignee (at issue)
Center Rock, 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.