Granted Patent
Utility
US 6,536,515 · App. 09/810,526
Evaporator foil stack
Inventors:
Oliver Freitag, Alois Tischler
Patented Case
View Patent ↗
Granted: Mar 25, 2003
Filed: Mar 19, 2001
Inventors
Oliver Freitag
Alois Tischler
Assignee (at issue)
BALLARD POWER SYSTEMS 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.