Inventor
CALDWELL CHARLES DAVID
US10 patents
⚠️ This page may combine multiple inventors who share the name “CALDWELL CHARLES DAVID”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.
AT & T CORP
5 patentsUS7027986B2Apr 11, 2006
Method and device for providing speech-to-text encoding and telephony service
AT & T CORP24 citations91
US6418202B1Jul 9, 2002
Spontaneous messaging service for prepaid calling card users
AT & T CORP37 citations90
US7627529B1Dec 1, 2009
Method and system for allowing simultaneous usage of prepaid services
AT & T CORP12 citations82
US7433818B2Oct 7, 2008
Subscriber terminal for providing speech-text encoding and telephony service
AT & T CORP2 citations61
US6687349B1Feb 3, 2004
System and method for defining a local communication space
AT & T CORP1 citations51