Granted Patent
Utility
US 5,671,772 · App. 08/747,266
Adjustable valve box
Inventor:
William C. Bliss
Patented Case
View Patent ↗
Granted: Sep 30, 1997
Filed: Nov 12, 1996
Inventor
William C. Bliss
Assignee (at issue)
Tyler Pipe Company, a div. of Ransom Industries, 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.