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CPC Subgroup
E21D 15/06

with parts joined by a lock, with or without slight axial adjustability

Full Title

Props (in the building art E04G25/00); Chocks > Non-telescopic props > with parts joined by a lock, with or without slight axial adjustability

3 direct subcodes

Child Classifications

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  • E21D 15/08 with toggle joint connection
  • E21D 15/10 with dog-clutch or pin-and-hole connection
  • E21D 15/12 with locking devices located near head or foot

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