Granted Patent
Utility
US 5,133,853 · App. 07/557,155
Sewage system
Inventors:
Roland Mattsson, Pentti Marjanen
Patented Case
View Patent ↗
Granted: Jul 28, 1992
Filed: Jul 20, 1990
Inventors
Roland Mattsson
Pentti Marjanen
Assignee (at issue)
Nesite Oy
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.