E21B 47/0232
At least one of the energy sources or one of the detectors
Official title: at least one of the energy sources or one of the detectors being located on or above the ground surface
E21B47/0232 (At least one of the energy sources or one of the detectors) appears on 307 US grants and 238 published applications in this corpus.
Search patents in E21B- Granted patents
- 307
- Published applications
- 238
- Assignees
- 73
- Inventors
- 281
- Latest grant
- 10 Feb 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 2 | 0 |
| 1977 | 2 | 0 |
| 1978 | 0 | 0 |
| 1979 | 0 | 0 |
| 1980 | 1 | 0 |
| 1981 | 0 | 0 |
| 1982 | 0 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 0 | 0 |
| 1987 | 2 | 0 |
| 1988 | 1 | 0 |
| 1989 | 9 | 0 |
| 1990 | 5 | 0 |
| 1991 | 4 | 0 |
| 1992 | 4 | 0 |
| 1993 | 3 | 0 |
| 1994 | 3 | 0 |
| 1995 | 3 | 0 |
| 1996 | 3 | 0 |
| 1997 | 5 | 0 |
| 1998 | 5 | 0 |
| 1999 | 13 | 0 |
| 2000 | 9 | 0 |
| 2001 | 8 | 4 |
| 2002 | 10 | 9 |
| 2003 | 12 | 15 |
| 2004 | 8 | 14 |
| 2005 | 15 | 17 |
| 2006 | 13 | 10 |
| 2007 | 10 | 8 |
| 2008 | 10 | 11 |
| 2009 | 8 | 12 |
| 2010 | 10 | 9 |
| 2011 | 12 | 11 |
| 2012 | 4 | 8 |
| 2013 | 7 | 8 |
| 2014 | 10 | 12 |
| 2015 | 9 | 9 |
| 2016 | 12 | 13 |
| 2017 | 11 | 15 |
| 2018 | 7 | 7 |
| 2019 | 13 | 9 |
| 2020 | 10 | 10 |
| 2021 | 11 | 7 |
| 2022 | 8 | 6 |
| 2023 | 5 | 3 |
| 2024 | 5 | 2 |
| 2025 | 4 | 7 |
| 2026 | 1 | 2 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Horizontal directional drilling area network and methods10 Feb 2026US 12,546,209 B2Merlin Technology, Inc.
- Tunneling and navigation system including distributed communication and sensing system4 Nov 2025US 12,461,261 B2GE Vernova Infrastructure Technology LLC
- Sonde with advanced battery power conservation and associated methods21 Oct 2025US 12,448,883 B2Merlin Technology, Inc.
- Systems and methods for ranging and tracking while drilling multiple geological wells6 May 2025US 12,291,966 B1Schlumberger Technology Corporation
- Advanced underground homing system, apparatus and method7 Jan 2025US 12,188,346 B2Merlin Technology, Inc.
- Beacon feedback for isolation of carrier signal27 Aug 2026US 2026/0254106 A1The Charles Machine Works, Inc.
- Horizontal Directional Drilling Guidence System23 Jul 2026US 2026/0210187 A1
- Advanced underground homing system, apparatus and method18 Dec 2025US 2025/0382870 A1Merlin Technology, Inc.
- Drone-based method of subterranean directional drilling control11 Sep 2025US 2025/0283379 A1Hazen International Energy Services Inc.
- Directional drilling device14 Aug 2025US 2025/0257612 A1
Most cited
By later US patents
- Method and apparatus employing received independent magnetic field components of a transmitted alternating magnetic field for determining location494US 4,710,708 ADevelco, Inc. · 1987
- Locator device for continuously locating a dipole magnetic field transmitter and its method of operation244US 5,337,002 A1994
- System for tracking and/or guiding an underground boring tool173US 6,035,951 ADigital Control Incorporated · 2000
- Electronic guidance system and method for locating a discrete in-ground boring device166US 5,585,726 AUTILX Corporation · 1996
- Wireless remote boring apparatus guidance system165US 5,469,155 AMcLaughlin Manufacturing Company, Inc. · 1995