Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8036354 | Calling-party-pays call processing for cellular and paging | Carol Shifrin Gruchala, Gordon Lynn Blumenschein, Douglas Marshall, Carlos Donoso | 2011-10-11 |
| 7257209 | Calling-party-pays call processing for cellular and paging | Carol Shifrin Gruchala, Gordon Lynn Blumenschein, Douglas Marshall, Carlos Donoso | 2007-08-14 |
| 6570970 | Calling-party-pays call processing for cellular and paging | Carol Shifrin Gruchala, Gordon Lynn Blumenschein, Douglas Marshall, Carlos Donoso | 2003-05-27 |
| 6263056 | Calling-party-pays call processing for cellular and paging | Carol Shifrin Gruchala, Gordon Lynn Blumenschein, Douglas Marshall, Carlos Donoso | 2001-07-17 |