Granted Patent
Utility
US 6,701,256 · App. 10/093,714
Exhaust opacity measuring device
Inventors:
Donald H. Stedman, Gary Bishop, Gary Full
Patented Case
View Patent ↗
Granted: Mar 2, 2004
Filed: Mar 11, 2002
Inventors
Donald H. Stedman
Gary Bishop
Gary Full
Assignee (at issue)
Environmental Systems Products Holdings 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.