Granted Patent
Utility
US 5,957,391 · App. 09/036,326
Drip irrigation hose with self-cleaning inlet and method for its manufacture
Inventors:
Michael DeFrank, Que Thuy Tran
Patented Case
View Patent ↗
Granted: Sep 28, 1999
Filed: Mar 6, 1998
Inventors
Michael DeFrank
Que Thuy Tran
Assignee (at issue)
T-SYSTEMS INTERNATIONAL 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.