Granted Patent
Utility
US 5,160,980 · App. 07/652,486
Test piece coloration comparative decision unit
Inventors:
Bernd G. Herpichboehm, George H. Sierra, Robert B. Summers, Thomas M. Watlington
Patented Case
View Patent ↗
Granted: Nov 3, 1992
Filed: Feb 8, 1991
Inventors
Bernd G. Herpichboehm
George H. Sierra
Robert B. Summers
Thomas M. Watlington
Assignee (at issue)
Boehringer Mannheim GmbH
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.