E21C 39/00 Devices for testing in situ the hardness or other properties of minerals, e.g. for giving information as to the selection of suitable mining tools
Introduced: September 1968
Title
Titles differ between systems:
IPC: Devices for testing the hardness or other properties of minerals, e.g. for giving information as to the selection of suitable mining tools
CPC: Devices for testing in situ the hardness or other properties of minerals, e.g. for giving information as to the selection of suitable mining tools
Full Title
Full titles differ between systems:
Devices for testing the hardness or other properties of minerals, e.g. for giving information as to the selection of suitable mining tools
Devices for testing in situ the hardness or other properties of minerals, e.g. for giving information as to the selection of suitable mining tools
No child classifications to compare. This is a leaf node in both IPC and CPC.
Top Applicants
Top Applicants (IPC)
Class E21,2013–2023, worldwide · Source: EPO PATSTAT
- HALLIBURTON ENERGY SERVICES GROUP US 26,607
- PETROCHINA COMPANY 14,382
- SINOPEC (CHINA PETROCHEMICAL CORPORATION) 10,137
- CNPC (CHINA NATIONAL PETROLEUM CORPORATION) 6,517
- BAKER HUGHES US 6,269
- SCHLUMBERGER TECHNOLOGY US 5,929
- SAUDI ARABIAN OIL COMPANY SA 5,880
- SOUTHWEST PETROLEUM UNIVERSITY 4,477
- CHINA UNIVERSITY OF MINING AND TECHNOLOGY 4,357
- SCHLUMBERGER TECHNOLOGY NL 4,219
Top Applicants (CPC)
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