by bending and interconnecting the ends of the workpieces with or without separate jointing members

Introduced: September 1968

Full Title

Full titles differ between systems:

IPC:

Making chains or chain links by bending workpieces of rod, wire, or strip to form links of oval or other simple shape > by bending and interconnecting the ends of the workpieces with or without separate jointing members

CPC:

Making chains or chain links by bending workpieces of rod, wire, or strip to form links of oval or other simple shape (B21L3/00, B21L7/00 take precedence) > by bending and interconnecting the ends of the workpieces with or without separate jointing members

No child classifications to compare. This is a leaf node in both IPC and CPC.

Top Applicants

Top Applicants (IPC)

Class B21,2013–2023, worldwide · Source: EPO PATSTAT

JFE STEEL 2,318
JFE STEEL JP 2,294
POSCO (POHANG IRON AND STEEL COMPANY) KR 2,083
NIPPON STEEL CORPORATION JP 1,650
NSSMC (NIPPON STEEL & SUMITOMO METAL) JP 1,631
SMS GROUP DE 1,472
BAOSHAN IRON & STEEL COMPANY 1,181
SGCC(STATE GRID CORPORATION OF CHINA) 1,079
ANHUI JIANGHUAI AUTOMOBILE 984
HYUNDAI STEEL COMPANY KR 980

Top Applicants (CPC)

Class B21,2013–2023, worldwide · Source: EPO PATSTAT

JFE STEEL JP 2,667
NIPPON STEEL CORPORATION JP 2,049
POSCO (POHANG IRON AND STEEL COMPANY) KR 1,967
NSSMC (NIPPON STEEL & SUMITOMO METAL) JP 1,800
SMS GROUP DE 1,538
JFE STEEL 1,150
ARCELORMITTAL LU 1,142
BAOSHAN IRON & STEEL COMPANY 821
HYUNDAI STEEL COMPANY KR 808
THYSSENKRUPP STEEL EUROPE DE 660