Granted Patent
Utility
US 6,144,847 · App. 09/371,398
Wireless telephone with credited airtime
Inventors:
Randice Lisa Altschul, Lee S. Volpe
Patented Case
View Patent ↗
Granted: Nov 7, 2000
Filed: Aug 10, 1999
Inventors
Randice Lisa Altschul
Lee S. Volpe
Assignee (at issue)
Dieceland Technologies Corp.
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.