| # | Country | Total Patents | |
|---|---|---|---|
| #1 | United States | 11 | |
| #2 | Canada | 3 | |
| #3 | Australia | 1 | |
| #4 | Egypt | 1 | |
| #5 | WIPO (World Intellectual Property Organization) | 1 |
| # | Industry | |
|---|---|---|
| #1 | Civil engineering |
| # | Technology | |
|---|---|---|
| #1 | Earth drilling |
| # | Name | Total Patents |
|---|---|---|
| #1 | Duhn Rex E | 16 |
| #2 | Meek Robert K | 10 |
| #3 | Duhn Jay C | 3 |
| #4 | Speirs Aaron B | 2 |
| #5 | Webster Kenneth D | 2 |
| #6 | Card Gary A | 1 |
| #7 | Chapman William D | 1 |
| Publication | Filing date | Title |
|---|---|---|
| US2006060349A1 | Wellhead isolation tool and method of fracturing a well | |
| CA2482335A1 | Wellhead isolation tool and method of fracturing a well | |
| US7493944B2 | Wellhead isolation tool and method of fracturing a well | |
| US6920925B2 | Wellhead isolation tool | |
| US6588510B2 | Coil tubing hanger system | |
| US6543533B2 | Well tubing rotator | |
| US6199914B1 | Drilling quick connectors | |
| US5303774A | Ring seal packer | |
| US4974676A | Ground subsiding wellhead |