CPC Subgroup
E21F 13/086 Full Title
Transport specially adapted to underground conditions (mine cars B61D; transport in general, loading B65G) > Shifting conveyors or other transport devices from one location at the working face to another (guiding mining machines along conveyors for the cut mineral E21C35/12; in combination with mine roof supports for step-by-step movement E21D23/00)
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