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PCE
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DIFF Subgroup
E21D 5/06

with iron or steel (E21D5/01, E21D5/012, E21D5/016 take precedence)

Introduced: September 1968

Title

Titles differ between systems:

IPC: with iron or steel

CPC: with iron or steel (E21D5/01, E21D5/012, E21D5/016 take precedence)

Full Title

Full titles differ between systems:

IPC:

Lining shafts; Linings therefor > with iron or steel

CPC:

Lining shafts; Linings therefor (E21D11/00 takes precedence ) > with iron or steel (E21D5/01, E21D5/012, E21D5/016 take precedence)

IPC and CPC are identically structured here. All 2 subcodes exist in both systems.

Child Classifications

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  • E21D 5/08 in the form of profiled parts IPC+CPC Available in IPC and CPC
  • E21D 5/10 in the form of tubbing 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