Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8132020 | System and method for user authentication with exposed and hidden keys | Yunzhou Zhu | 2012-03-06 |
| 7711786 | Systems and methods for preventing spam | Yunzhou Zhu | 2010-05-04 |