04723273 is referenced by 102 patents and cites 3 patents.

A call forwarding method that allows the called party to selectively forward individual alerting calls based, for example, on the calling party identity or on how busy the called party is at any given time, but without requiring the called party to first answer the calls. The called party can effect the transfer even though engaged in conversation with someone else.

Title
Discretionary call forwarding
Application Number
6/779863
Publication Number
4723273
Application Date
September 25, 1985
Publication Date
February 2, 1988
Inventor
Louis M Taff
Warrenville
IL, US
Michael E Diesel
Newark
IL, US
Agent
Ross T Watland
Assignee
American Telephone and Telegraph Company AT&T Bell Laboratories
NJ, US
IPC
H04M 3/58
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