Granted Patent
Utility
US 5,155,481 · App. 07/528,391
Two and three wire utility data communications system
Inventors:
William J. Brennan, David Hamilton, Warren Wynn
Patented Case
View Patent ↗
Granted: Oct 13, 1992
Filed: May 25, 1990
Inventors
William J. Brennan
David Hamilton
Warren Wynn
Assignee (at issue)
Schlumberger Industires, S.A.
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.