Granted Patent
Utility
US 6,086,297 · App. 09/160,026
Apparatus for forming grooves in bell-shaped pipes
Inventor:
Ray Lotfi
Patented Case
View Patent ↗
Granted: Jul 11, 2000
Filed: Sep 24, 1998
Inventor
Ray Lotfi
Assignee (at issue)
CERTAINTEED LLC
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.