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DIFF Subgroup
E21B 34/08

responsive to flow or pressure of the fluid obtained (E21B34/10 takes precedence)

Introduced: January 1980

Title

Titles differ between systems:

IPC: responsive to flow or pressure of the fluid obtained

CPC: responsive to flow or pressure of the fluid obtained (E21B34/10 takes precedence)

Full Title

Full titles differ between systems:

IPC:

Valve arrangements for boreholes or wells > in wells > responsive to flow or pressure of the fluid obtained

CPC:

Valve arrangements for boreholes or wells > in wells > responsive to flow or pressure of the fluid obtained (E21B34/10 takes precedence)

Of 1 combined children, 0 exist in both systems.

1 codes are CPC-only extensions.

Child Classifications

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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