DIFF Subgroup
C04B 11/05 obtaining anhydrite, (C04B11/028 takes precedence)
Introduced: January 1985
Title
Titles differ between systems:
IPC: obtaining anhydrite
CPC: obtaining anhydrite, (C04B11/028 takes precedence)
Full Title
Full titles differ between systems:
IPC:
Calcium sulfate cements > obtaining anhydrite
CPC:
Calcium sulfate cements > obtaining anhydrite, (C04B11/028 takes precedence)
No child classifications to compare. This is a leaf node in both IPC and CPC.
Top Applicants
Top Applicants (IPC)
Class C04,2013–2023, worldwide · Source: EPO PATSTAT
- CHINESE ACADEMY OF SCIENCES 2,095
- WUHAN UNIVERSITY OF TECHNOLOGY 1,205
- NGK INSULATORS JP 1,133
- HALLIBURTON ENERGY SERVICES GROUP US 1,049
- SIKA TECHNOLOGY CH 1,041
- GUILIN UNIVERSITY OF TECHNOLOGY 807
- WUHAN UNIVERSITY OF SCIENCE AND TECHNOLOGY 806
- SOUTHEAST UNIVERSITY 801
- CORNING US 777
- UNITED STATES GYPSUM COMPANY US 739
Top Applicants (CPC)
Class C04,2013–2023, worldwide · Source: EPO PATSTAT
- HALLIBURTON ENERGY SERVICES GROUP US 2,158
- CHINESE ACADEMY OF SCIENCES 1,569
- NGK INSULATORS JP 1,504
- SIKA TECHNOLOGY CH 1,181
- CORNING US 974
- WUHAN UNIVERSITY OF TECHNOLOGY 926
- UNITED STATES GYPSUM COMPANY US 882
- GE (GENERAL ELECTRIC COMPANY) US 828
- MITSUBISHI MATERIALS CORPORATION JP 792
- SAUDI ARABIAN OIL COMPANY SA 686