| 9235972 |
Personal security and tracking system |
Mark Hoffman, Judd Hoffman, David Doe |
2016-01-12 |
| 8466795 |
Personal security and tracking system |
Mark Hoffman, Judd Hoffman, David Doe |
2013-06-18 |
| 8149124 |
Personal security and tracking system |
Mark Hoffman, Judd Hoffman, David Doe |
2012-04-03 |
| 7038590 |
Personal security and tracking system |
Mark Hoffman, Judd Hoffman, David Doe |
2006-05-02 |
| 6624754 |
Personal security and tracking system |
Mark Hoffman, Judd Hoffman, David Doe |
2003-09-23 |
| 6239700 |
Personal security and tracking system |
Mark Hoffman, Judd Hoffman, David Doe |
2001-05-29 |
| 5742233 |
Personal security and tracking system |
Mark Hoffman, Judd Hoffman, David Doe |
1998-04-21 |