Granted Patent
Utility
US 4,652,172 · App. 06/847,158
Method and equipment for improving horizontal marking strips
Inventor:
Ludwig Eigenmann
Patented Case
View Patent ↗
Granted: Mar 24, 1987
Filed: Apr 2, 1986
Inventor
Ludwig Eigenmann
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.