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CPC Main Group Additional Only
E21B 2200/00

Special features related to earth drilling for obtaining oil, gas or water

Filing statistics

CPC E21B 2200/00 belongs to the parent subclass E21B, which recorded 241,108 patent applications worldwide between 2013 and 2023. Annual filings declined from 20,629 in 2013 to 18,982 in 2023 (-8%), peaking at 24,423 applications in 2016. The most active applicants in class E21 are HALLIBURTON ENERGY SERVICES GROUP (27,652 applications), SAUDI ARABIAN OIL COMPANY (7,755 applications) and PETROCHINA COMPANY (7,025 applications).

Source: EPO PATSTAT, worldwide filings

10 direct subcodes

Child Classifications

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  • E21B 2200/01 Sealings characterised by their shape
  • E21B 2200/02 Down-hole chokes or valves for variably regulating fluid flow
  • E21B 2200/03 Valves operated by gear mechanisms, e.g. rack and pinion mechanisms
  • E21B 2200/04 Ball valves
  • E21B 2200/05 Flapper valves
  • E21B 2200/06 Sleeve valves
  • E21B 2200/08 Down-hole devices using materials which decompose under well-bore conditions
  • E21B 2200/09 Detecting, eliminating, preventing liquid slugs in production pipes
  • E21B 2200/20 Computer models or simulations, e.g. for reservoirs under production, drill bits
  • E21B 2200/22 Fuzzy logic, artificial intelligence, neural networks or the like

Top Applicants

Top 10 applicants by patent filingsfor 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