- 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 47/053 - Measuring depth or liquid level using radioactive markers
Patent holdings for IPC class E21B 47/053
Total number of patents in this class: 12
10-year publication summary
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0
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0
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0
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1
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3
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3
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3
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1
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1
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0
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| 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| CARBO Ceramics Inc. | 236 |
4 |
| Halliburton Energy Services, Inc. | 20991 |
3 |
| Saudi Arabian Oil Company | 13442 |
2 |
| Schlumberger Technology Corporation | 10930 |
1 |
| Baker Hughes Incorporated | 5238 |
1 |
| Shell USA, Inc. | 1244 |
1 |
| Other owners | 0 |