CPC Main Group
E21D 15/00 Props (in the building art E04G25/00); Chocks
8 direct subcodes
Child Classifications
Navigate with arrow keys, Enter to open
- E21D 15/02 Non-telescopic props
- E21D 15/14 Telescopic props (general means for fixing telescopic parts together )
- E21D 15/48 Chocks or the like
- E21D 15/50 Component parts or details of props (E21D15/43, E21D15/58, E21D15/60 take precedence)
- E21D 15/58 Devices for setting props or chocks
- E21D 15/60 Devices for withdrawing props or chocks
Top Applicants
Top 10 applicants by patent filingsfor class E21, 2013–2023, worldwide · Source: EPO PATSTAT
- HALLIBURTON ENERGY SERVICES GROUP US 27,652
- SAUDI ARABIAN OIL COMPANY SA 7,755
- PETROCHINA COMPANY 7,025
- BAKER HUGHES US 6,589
- SCHLUMBERGER TECHNOLOGY US 6,151
- SINOPEC (CHINA PETROCHEMICAL CORPORATION) 4,443
- SCHLUMBERGER TECHNOLOGY NL 4,255
- CNPC (CHINA NATIONAL PETROLEUM CORPORATION) 3,991
- SERVICES PETROLIERS SCHLUMBERGER FR 3,300
- SCHLUMBERGER CANADA CA 3,086