Granted Patent
Utility
US 6,208,987 · App. 09/115,540
Hierarchically structured indexed information retrieval system
Inventor:
Katsumi Nihei
Patented Case
View Patent ↗
Granted: Mar 27, 2001
Filed: Jul 15, 1998
Inventor
Katsumi Nihei
Assignee (at issue)
NEC CORPORATION
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.