Granted Patent
Utility
US 6,357,549 · App. 09/586,013
Guide rail climbing lifting platform and method
Inventors:
Donald D. Brennan, Brent R. Leisening, Carl W. Diedrich, George Burkhart, Ralph Douglas Fredrickson
Patented Case
View Patent ↗
Granted: Mar 19, 2002
Filed: Jun 2, 2000
Inventors
Donald D. Brennan
Brent R. Leisening
Carl W. Diedrich
George Burkhart
Ralph Douglas Fredrickson
Assignees (at issue)
D. H. Blattner & Sons, Inc.
Elgood Mayo Corp.
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.