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IPC Main Group
C21D 7/00

Modifying the physical properties of iron or steel by deformation

Introduced: September 1968

Last revised: January 2006

Classification Context

Section:
CHEMISTRY; METALLURGY
Class:
METALLURGY OF IRON
Subclass:
MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING

Filing statistics

IPC C21D 7/00 belongs to the parent subclass C21D, which recorded 149,911 patent applications worldwide between 2013 and 2023. Annual filings grew from 9,561 in 2013 to 16,467 in 2023 (+72%), peaking at 16,959 applications in 2020. The most active applicants in class C21 are JFE STEEL (7,470 applications), POSCO (POHANG IRON AND STEEL COMPANY) (4,615 applications) and JFE STEEL (4,538 applications).

Source: EPO PATSTAT, worldwide filings

Related Keywords

HARDENING of iron or steelhardening of IRONmodifying physical properties of IRON by working

2 direct subcodes

Child Classifications

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Top Applicants

Top 10 applicants by patent filingsfor class C21, 2013–2023, worldwide · Source: EPO PATSTAT

  1. JFE STEEL JP 7,470
  2. POSCO (POHANG IRON AND STEEL COMPANY) KR 4,615
  3. JFE STEEL 4,538
  4. NIPPON STEEL CORPORATION JP 4,536
  5. ARCELORMITTAL LU 2,597
  6. NSSMC (NIPPON STEEL & SUMITOMO METAL) JP 2,241
  7. ANGANG STEEL COMPANY 2,126
  8. NSSMC (NIPPON STEEL & SUMITOMO METAL) 1,783
  9. BAOSHAN IRON & STEEL COMPANY 1,620
  10. HYUNDAI STEEL COMPANY KR 1,545