AT&T always had a history of patenting its inventions. Bell Labs was the source of most of those. Although Conversant wasn’t a research organization, it was based on a number of innovations. The following are some of the patents from the Conversant team that were core to the product.
Walls, J. E. (1983) Frequency Signaling Method and Apparatus with Dynamic Compensation for Frequency Errors. (U.S. Patent 4.401,860) – Patent describing Special Intercept Tones (SIT) and their detection. Although this work was done as part of the SES project, the ability of Conversant to detect and analyze SITs was key to its ability to do “call classification analysis.”
Belfield, W. R.; Erwin, W. J.; Geers Jr, T.; Grubbe, R. V.; Handy, S. W.; Perdue, R. J. (1990) Password Controlled Switching System. (U.S. Patent 4,896,346) – Patent describes using a method to interact with a caller and ascertain the caller’s login & password to enable a telephone switch controlled by this application to securely grant the caller access to restricted features of the switch.
Deng, D. L.; Mattson, L. M.; Perdue, R. J.; Rissanen, E. (1991) Voice Capture System. (U.S. Patent 5,003,574) – Patent describes a means of collecting a voice form or survey from a caller via a telephone call with the caller’s responses saved for transcription.
Gokcen, S. I.; Grubbe, R. V.; Perdue, R. J. (1992) Voice Response Unit. (U.S. Patent 5,125,024) – Patent that describes the fundamental features of a speech enabled interactive voice response system.
Bocchieri, E. L.; Gokcen, S. I.; Mikkilineni, R. P.; Roe, D. B.; Wilpon, J. G. (1994) Automatic Speech Recognizer. (U.S. Patent 5,329,608) – Patent on the speech recognition technique that was called Flex Word speech recognition.