Granted Patent
Utility
US 5,778,938 · App. 08/598,907
Method of installation of dual containment pipe rehabilitation system
Inventors:
Douglas K. Chick, F. Thomas Driver
Patented Case
View Patent ↗
Granted: Jul 14, 1998
Filed: Feb 9, 1996
Inventors
Douglas K. Chick
F. Thomas Driver
Assignee (at issue)
Insituform (Netherlands) B.V.
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.