Average Co-Inventor Count = 2.00
ph-index = 3
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. At+t Corp. (1 from 4,208 patents)
2. At&t Bell Laboratories (1 from 3,345 patents)
3. At&t Ipm Corp. (1 from 91 patents)
3 patents:
1. 5699416 - Method for obtaining billing validation of directory number accounts
2. 5487107 - Method and apparatus for processing telephone calls charged to credit
3. 5287403 - Method and apparatus for processing telephone calls charged to credit