Granted Patent
Utility
US 6,536,498 · App. 09/190,373
Welding apparatus and method for joining roofing materials
Inventors:
Krishna Srinivasan, Brian Duffy
Patented Case
View Patent ↗
Granted: Mar 25, 2003
Filed: Nov 12, 1998
Inventors
Krishna Srinivasan
Brian Duffy
Assignee (at issue)
Building Materials Corporation of America
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.