Granted Patent
Utility
US 5,961,709 · App. 09/025,873
Environmentally improved asphalt compositions and their preparation
Inventors:
Roger E. Hayner, Patricia K. Doolin, James F. Hoffman, Robert H. Wombles
Patented Case
View Patent ↗
Granted: Oct 5, 1999
Filed: Feb 19, 1998
Inventors
Roger E. Hayner
Patricia K. Doolin
James F. Hoffman
Robert H. Wombles
Assignee (at issue)
Marathon Ashland Petroleum LLC
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.