- All sections
- E - Fixed constructions
- E21D - Shafts; tunnels; galleries; large underground chambers
- E21D 5/01 - Lining shafts; Linings therefor using prefabricated lining lowered into a hole filled with liquid or viscous mass
Patent holdings for IPC class E21D 5/01
Total number of patents in this class: 9
10-year publication summary
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0
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0
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0
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0
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1
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0
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0
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0
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3
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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
|
|---|---|---|
| Halliburton Energy Services, Inc. | 20438 |
2 |
| Schlumberger Technology Corporation | 10263 |
1 |
| Schlumberger Canada Limited | 7154 |
1 |
| Schlumberger Technology B.v. | 5075 |
1 |
| Schlumberger Holdings Limited | 2867 |
1 |
| Prad Research and Development Limited | 2696 |
1 |
| Services Petroliers Schlumberger | 5633 |
1 |
| Wang, Fuming | 12 |
1 |
| Other owners | 0 |