Granted Patent
Utility
US 4,732,997 · App. 06/932,211
Dibenzoxaphosphorin compounds
Inventors:
Paul Tschopp, David G. Leppard
Patented Case
View Patent ↗
Granted: Mar 22, 1988
Filed: Nov 18, 1986
Inventors
Paul Tschopp
David G. Leppard
Assignee (at issue)
Ciba-Geigy
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.