- All sections
- E - Fixed constructions
- E21B - Earth or rock drillingobtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B 25/04 - Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors the core receiver being insertable into, or removable from, the borehole without withdrawing the drilling pipe the core receiver having a core forming cutting edge or element, e.g. punch type core barrels
Patent holdings for IPC class E21B 25/04
Total number of patents in this class: 32
10-year publication summary
|
1
|
2
|
1
|
1
|
6
|
5
|
2
|
6
|
0
|
0
|
| 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| Baker Hughes Incorporated | 5277 |
6 |
| Halliburton Energy Services, Inc. | 20835 |
3 |
| Longyear TM, Inc. | 105 |
3 |
| Reflex Instruments Asia Pacific Pty Ltd | 86 |
3 |
| Boart Longyear Company | 154 |
3 |
| Diaset Products Ltd. | 8 |
2 |
| Andre Lafleur RD & D Inc. | 4 |
1 |
| Australian Mud Company Pty Ltd | 16 |
1 |
| Bly IP Inc. | 31 |
1 |
| Shenzhen University | 1637 |
1 |
| Sichuan University | 564 |
1 |
| Baker Hughes, a GE Company, LLC | 2114 |
1 |
| Hunan University of Science and Technology | 66 |
1 |
| China Railway Hi-tech Industry Corporation Limited | 15 |
1 |
| The Board of Regents for the Oklahoma Agricultural and Mechanical Colleges | 69 |
1 |
| China Railway Jiujiang Bridge Engineering Co., Ltd. | 12 |
1 |
| Hunan Sea Bull Geological Exploration Co.,Ltd | 3 |
1 |
| Veracio Ltd. | 1 |
1 |
| Other owners | 0 |