Average Co-Inventor Count = 1.77
ph-index = 7
The patent ph-index is calculated by counting the number of publications for which an author has been cited by other authors at least that same number of times.
Company Filing History:
1. Duhn Oil Tool, Inc. (10 from 11 patents)
2. Seaboard International Inc. (5 from 19 patents)
3. Other (1 from 832,718 patents)
4. Shell Western E&p Inc. (1 from 22 patents)
5. Duhn Industries (1 from 1 patent)
17 patents:
1. 11976542 - Frac distribution tower
2. 8863829 - Wellhead isolation tool and wellhead assembly incorporating the same
3. 8333237 - Wellhead isolation tool and wellhead assembly incorporating the same
4. RE43773 - Drilling quick connectors
5. RE43697 - Drilling quick connectors
6. 8272433 - Wellhead isolation tool and wellhead assembly incorporating the same
7. 7726393 - Wellhead isolation tool and wellhead assembly incorporating the same
8. 7520322 - Wellhead isolation tool and method of fracturing a well
9. 7493944 - Wellhead isolation tool and method of fracturing a well
10. 7416020 - Wellhead isolation tool, wellhead assembly incorporating the same, and method of fracturing a well
11. 7322407 - Wellhead isolation tool and method of fracturing a well
12. 6920925 - Wellhead isolation tool
13. 6543533 - Well tubing rotator
14. 6199914 - Drilling quick connectors
15. 5611398 - Two-piece drilling flange