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CPC Main Group
E21C 35/00

Details of, or accessories for, machines for slitting or completely freeing the mineral from the seam, not provided for in groups E21C25/00 - E21C33/00, E21C37/00 or E21C39/00

10 direct subcodes

Child Classifications

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  • E21C 35/02 Locking equipment for slewable parts
  • E21C 35/06 Equipment for positioning the whole machine in relation to its sub-structure
  • E21C 35/20 General features of equipment for removal of chippings, e.g. for loading on conveyor
  • E21C 35/24 Remote control specially adapted for machines for slitting or completely freeing the mineral (control in general G05)

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