Granted Patent
Utility
US 4,515,562 · App. 06/645,341
Apparatus for applying heat to a portion of a pipeline
Inventor:
John P. Williams
Patented Case
View Patent ↗
Granted: May 7, 1985
Filed: Aug 29, 1984
Inventor
John P. Williams
Assignee (at issue)
British Gas
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.