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DIFF Main Group
E21B 44/00

Automatic control systems specially adapted for drilling operations, i.e. self-operating systems which function to carry out or modify a drilling operation without intervention of a human operator, e.g. computer-controlled drilling systems; Systems specially adapted for monitoring a plurality of drilling variables or conditions

Introduced: January 1980

Of 3 combined children, 2 exist in both systems.

1 codes are CPC-only extensions.

1 shared codes have differing titles between IPC and CPC.

IPC defines codes here since 2000.

Child Classifications

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  • E21B 44/005 CPC only CPC only
  • E21B 44/10 Arrangements for automatic stopping when the tool is lifted from the working face since 2000 IPC+CPC Available in 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