Average Co-Inventor Count = 1.33
ph-index = 2
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. (1 from 386 patents)
2. At&t Information Systems Inc. (1 from 243 patents)
3. American Telephone and Telegraph Company and At&t Information Systems (1 from 7 patents)
2 patents:
1. 4739509 - Automated message chronicling system
2. 4734931 - Integrated calling directory