- All sections
- E - Fixed constructions
- E21C - Mining or quarrying
- E21C 41/20 - Methods of underground miningLayouts therefor for rock salt or potash salt
Patent holdings for IPC class E21C 41/20
Total number of patents in this class: 15
10-year publication summary
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0
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1
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1
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1
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1
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3
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1
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1
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1
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2
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| 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 |