- All sections
- E - Fixed constructions
- E21D - Shaftstunnelsgallerieslarge underground chambers
- E21D 5/012 - Use of fluid-tight or anti-friction material on outside of, or between, lining layers
Patent holdings for IPC class E21D 5/012
Total number of patents in this class: 2
10-year publication summary
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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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0
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0
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0
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0
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| 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| Jamal Rostami Engineering Services LLC | 4 |
1 |
| TopEng Inc. | 5 |
1 |
| Other owners | 0 |