Granted Patent
Utility
US 6,660,199 · App. 09/766,856
Pipe structure and method of manufacture
Inventors:
Roger Siferd, Matthew C. Ankrom, Larry E. Porter
Patented Case
View Patent ↗
Granted: Dec 9, 2003
Filed: Jan 19, 2001
Inventors
Roger Siferd
Matthew C. Ankrom
Larry E. Porter
Assignee (at issue)
Hancor, 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.