Issued Patents 2021
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 11118442 | Boring tool tracking fundamentally based on drill string length, pitch and roll | James W. Burrows, John E. Mercer | 2021-09-14 |
| 11035218 | Advanced steering tool system, method and apparatus | Albert W. Chau, Rudolf Zeller, John E. Mercer | 2021-06-15 |
| 10895145 | Advanced underground homing system, apparatus and method | John E. Mercer, Albert W. Chau | 2021-01-19 |