E21C 41/20
For rock salt or potash salt
Official title: for rock salt or potash salt
E21C41/20 (For rock salt or potash salt) appears on 25 US grants and 14 published applications in this corpus.
Search patents in E21C- Granted patents
- 25
- Published applications
- 14
- Assignees
- 16
- Inventors
- 32
- Latest grant
- 7 Apr 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 2 | 0 |
| 1978 | 1 | 0 |
| 1979 | 0 | 0 |
| 1980 | 3 | 0 |
| 1981 | 3 | 0 |
| 1982 | 0 | 0 |
| 1983 | 1 | 0 |
| 1984 | 1 | 0 |
| 1985 | 1 | 0 |
| 1986 | 0 | 0 |
| 1987 | 1 | 0 |
| 1988 | 0 | 0 |
| 1989 | 0 | 0 |
| 1990 | 0 | 0 |
| 1991 | 0 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 0 | 0 |
| 1998 | 0 | 0 |
| 1999 | 0 | 0 |
| 2000 | 0 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 0 |
| 2005 | 0 | 0 |
| 2006 | 0 | 0 |
| 2007 | 0 | 0 |
| 2008 | 0 | 0 |
| 2009 | 0 | 0 |
| 2010 | 0 | 0 |
| 2011 | 0 | 0 |
| 2012 | 0 | 1 |
| 2013 | 0 | 0 |
| 2014 | 0 | 0 |
| 2015 | 0 | 0 |
| 2016 | 0 | 2 |
| 2017 | 1 | 0 |
| 2018 | 0 | 1 |
| 2019 | 0 | 1 |
| 2020 | 2 | 1 |
| 2021 | 0 | 2 |
| 2022 | 2 | 2 |
| 2023 | 2 | 1 |
| 2024 | 1 | 2 |
| 2025 | 2 | 1 |
| 2026 | 1 | 0 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Rotary boring mining machine inertial steering system7 Apr 2026US 12,595,733 B2The Mosaic Company
- Leaching fluid control systems for mining operations16 Sep 2025US 12,416,063 B2Southwest Leaching Technologies, LLC
- Processes and configurations for subterranean resource extraction26 Aug 2025US 12,398,636 B2102062448 Saskatchewan Ltd.
- Rotary boring mining machine inertial steering system18 Jun 2024US 12,012,855 B2The Mosaic Company
- Processes and configurations for subterranean resource extraction29 Aug 2023US 11,739,624 B2102062448 Saskatchewan Ltd.
- Miner automated hardware installation system and automated brattice installer5 Jun 2025US 2025/0179917 A1The Mosaic Company
- Rotary boring mining machine inertial steering system26 Sep 2024US 2024/0318552 A1The Mosaic Company
- Leaching fluid control systems for mining operations15 Aug 2024US 2024/0271246 A1Southwest Leaching Technologies, LLC
- Processes and configurations for subterranean resource extraction9 Nov 2023US 2023/0358128 A1102062448 Saskatchewan Ltd.
- Rotary boring mining machine inertial steering system3 Nov 2022US 2022/0349304 A1The Mosaic Company
Most cited
By later US patents
- Solution mining water soluble salts at high temperatures63US 4,232,902 APPG Industries, Inc. · 1980
- Solution mining of trona or nahcolite ore with aqueous NaOH and HCl solvents46US 4,498,706 AIntermountain Research and Development Corporation · 1985
- Solution mining of trona or nahcolite ore with electrodialytically-produced aqueous sodium hydroxide41US 4,652,054 AIntermountain Research and Development Corporation · 1987
- Recovery of alkali values from salt-containing trona deposits39US 4,401,635 AIntermountain Research and Development Corporation · 1983
- Subterranean drilling and slurry mining21US 4,067,617 AFMC Corporation · 1978