Average Co-Inventor Count = 2.86
ph-index = 6
The patent ph-index is calculated by counting the number of publications for which an author has been cited by other authors at least that same number of times.
Company Filing History:
1. American Telephone and Telegraph, Co. (3 from 386 patents)
2. At&t Information Systems Inc. (3 from 243 patents)
3. At&t Bell Laboratories (1 from 3,345 patents)
4. At&t Company (1 from 29 patents)
5. American Telephone and Telegraph Company and At&t Information Systems (1 from 7 patents)
6 patents:
1. 5172408 - Speakerphone state-controlled alerting arrangement
2. 4935954 - Automated message retrieval system
3. D305538 - Communications workstation
4. D305537 - Communications workstation
5. D305423 - Communications workstation
6. 4734931 - Integrated calling directory