Granted Patent
Utility
US 4,271,513 · App. 06/037,383
Method and apparatus for carrying out loopback test
Inventors:
Hiroshi Maejima, Noriaki Fujimura, Takahiro Shibuya, Shigeyuki Akagi
Patented Case
View Patent ↗
Granted: Jun 2, 1981
Filed: May 9, 1979
Inventors
Hiroshi Maejima
Noriaki Fujimura
Takahiro Shibuya
Shigeyuki Akagi
Assignees (at issue)
Nippon Telegraph and Telephone Public Corporation
Fujitsu Limited
OKI ELECTRIC INDUSTRY CO., LTD.
NIPPON ELECTRIC CO., LTD.
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.