CPC Main Group
C21C 5/00 Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel
6 direct subcodes
Child Classifications
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- C21C 5/02 Crucible furnace process
- C21C 5/04 Manufacture of hearth-furnace steel, e.g. Siemens-Martin steel
- C21C 5/28 Manufacture of steel in the converter
- C21C 5/52 Manufacture of steel in electric furnaces (; electric heating per se H05B)
- C21C 5/56 Manufacture of steel by other methods (making liquid steel by direct processes C21B13/00 )
Top Applicants
Top 10 applicants by patent filingsfor class C21, 2013–2023, worldwide · Source: EPO PATSTAT
- JFE STEEL JP 8,270
- NIPPON STEEL CORPORATION JP 5,222
- POSCO (POHANG IRON AND STEEL COMPANY) KR 4,824
- JFE STEEL 3,311
- ARCELORMITTAL LU 3,239
- NSSMC (NIPPON STEEL & SUMITOMO METAL) JP 2,659
- HYUNDAI STEEL COMPANY KR 1,492
- ANGANG STEEL COMPANY 1,318
- BAOSHAN IRON & STEEL COMPANY 1,233
- KOBE STEEL JP 1,228