Granted Patent
Utility
US 5,012,052 · App. 07/173,297
Isotope-ratio-monitoring gas chromatography-mass spectrometry apparatus and method
Inventor:
John Michael Hayes
Patented Case
View Patent ↗
Granted: Apr 30, 1991
Filed: Mar 22, 1988
Inventor
John Michael Hayes
Assignee (at issue)
THE TRUSTEES OF INDIANA UNIVERSITY
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.