Granted Patent
Utility
US 5,560,433 · App. 08/241,646
Dual action earth working implement
Inventors:
William L. Grimm, Austin W. Lutz, Jr.
Patented Case
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Granted: Oct 1, 1996
Filed: May 12, 1994
Inventors
William L. Grimm
Austin W. Lutz, Jr.
Assignee (at issue)
Case GmbH
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.