Skip to content
PCE
Search Classifications
Search for IPC and CPC classification codes or keywords
DIFF Subgroup
E21B 47/0232

at least one of the energy sources or one of the detectors being located on or above the ground surface

Introduced: January 2012

Full Title

Full titles differ between systems:

IPC:

Survey of boreholes or wells > Determining slope or direction > of the borehole, e.g. using geomagnetism > using electromagnetic energy or detectors therefor > at least one of the energy sources or one of the detectors being located on or above the ground surface

CPC:

Survey of boreholes or wells (monitoring pressure or flow of drilling fluid E21B21/08) > Determining slope or direction > of the borehole, e.g. using geomagnetism > using electromagnetic energy or detectors therefor > at least one of the energy sources or one of the detectors being located on or above the ground surface

No child classifications to compare. This is a leaf node in both IPC and CPC.

Top Applicants

Top Applicants (IPC)

Class E21,2013–2023, worldwide · Source: EPO PATSTAT

  1. HALLIBURTON ENERGY SERVICES GROUP US 26,607
  2. PETROCHINA COMPANY 14,382
  3. SINOPEC (CHINA PETROCHEMICAL CORPORATION) 10,137
  4. CNPC (CHINA NATIONAL PETROLEUM CORPORATION) 6,517
  5. BAKER HUGHES US 6,269
  6. SCHLUMBERGER TECHNOLOGY US 5,929
  7. SAUDI ARABIAN OIL COMPANY SA 5,880
  8. SOUTHWEST PETROLEUM UNIVERSITY 4,477
  9. CHINA UNIVERSITY OF MINING AND TECHNOLOGY 4,357
  10. SCHLUMBERGER TECHNOLOGY NL 4,219

Top Applicants (CPC)

Class E21,2013–2023, worldwide · Source: EPO PATSTAT

  1. HALLIBURTON ENERGY SERVICES GROUP US 27,652
  2. SAUDI ARABIAN OIL COMPANY SA 7,755
  3. PETROCHINA COMPANY 7,025
  4. BAKER HUGHES US 6,589
  5. SCHLUMBERGER TECHNOLOGY US 6,151
  6. SINOPEC (CHINA PETROCHEMICAL CORPORATION) 4,443
  7. SCHLUMBERGER TECHNOLOGY NL 4,255
  8. CNPC (CHINA NATIONAL PETROLEUM CORPORATION) 3,991
  9. SERVICES PETROLIERS SCHLUMBERGER FR 3,300
  10. SCHLUMBERGER CANADA CA 3,086