- 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 25/00 - Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors
Patent holdings for IPC class E21B 25/00
Total number of patents in this class: 452
10-year publication summary
|
30
|
34
|
41
|
21
|
48
|
33
|
41
|
26
|
10
|
11
|
| 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| Saudi Arabian Oil Company | 12997 |
33 |
| Baker Hughes Incorporated | 5273 |
31 |
| Shenzhen University | 1638 |
30 |
| Halliburton Energy Services, Inc. | 20862 |
29 |
| Sichuan University | 564 |
28 |
| Schlumberger Technology Corporation | 10673 |
12 |
| Aramco Services Company | 3936 |
9 |
| Reflex Instruments Asia Pacific Pty Ltd | 86 |
9 |
| Flexidrill Limited | 46 |
8 |
| National Oilwell Varco, L.P. | 1665 |
7 |
| Minalyze AB | 8 |
6 |
| Baker Hughes, a GE Company, LLC | 2113 |
6 |
| Schlumberger Canada Limited | 7283 |
5 |
| Chevron U.S.A. Inc. | 3945 |
5 |
| Prospectors IP Holdings Pty Ltd | 11 |
5 |
| Epiroc Canada Inc. | 18 |
5 |
| Boart Longyear Manufacturing and Distribution Inc. | 112 |
5 |
| Schlumberger Technology B.v. | 5164 |
4 |
| BP Exploration Operating Company Limited | 266 |
4 |
| China Oilfield Services Limited | 87 |
4 |
| Other owners | 207 |