B21 MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
Description
Class B21 covers mechanical metal-working processes that shape or deform metal without significant material removal, including punching, stamping, bending, drawing, and forging operations. It encompasses machinery, tools, and methods used in cold and hot forming of metals, as well as related processes like shearing and blanking. This class excludes metal cutting and machining operations (covered in B23), welding (B23K), and non-mechanical metal treatment such as casting or heat treatment without forming.
Filing statistics
CPC B21 recorded 264,031 patent applications worldwide between 2013 and 2023, summed across its 9 subclasses. Annual filings grew from 13,868 in 2013 to 24,845 in 2023 (+79%), peaking at 31,661 applications in 2020. The most active applicants in class B21 are JFE STEEL (2,667 applications), NIPPON STEEL CORPORATION (2,049 applications) and POSCO (POHANG IRON AND STEEL COMPANY) (1,967 applications).
Source: EPO PATSTAT, worldwide filings
9 direct subcodes
Child Classifications
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- B21B ROLLING OF METAL (auxiliary operations used in connection with metal-working operations covered in B21, see B21C; bending by rolling B21D; manufacture of particular objects, e.g. screws, wheels, rings, barrels, balls, by rolling B21H; pressure welding by means of a rolling mill B23K20/04)
- B21C MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES, PROFILES OR LIKE SEMI-MANUFACTURED PRODUCTS OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21D WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL (working or processing of wire B21F)
- B21F WORKING OR PROCESSING OF METAL WIRE (rolling of metal wire B21B1/16; by drawing, auxiliary operations used in connection with metal-working without essentially removing material B21C)
- B21G MAKING NEEDLES, PINS OR NAILS OF METAL
- B21H MAKING PARTICULAR METAL OBJECTS BY ROLLING, e.g. SCREWS, WHEELS, RINGS, BARRELS, BALLS (essentially from sheet metal B21D)
- B21J FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES (rolling of metal B21B; making particular products by forging or pressing B21K; cladding or plating B23K; finishing surfaces by hammering B23P9/04; compacting surfaces by blasting with particulate material B24C1/10; general features of presses, presses for consolidating scrap B30B; furnaces in general F27)
- B21K MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS (making particular articles by working sheet metal without essentially removing material B21D; processing wire B21F; making pins, needles or nails B21G; making particular articles by rolling B21H; forging machines, pressing machines, hammering machines, in general B21J; making chains B21L; plating B23K)
- B21L MAKING METAL CHAINS (making chains or chain links by casting B22D25/02; chains in general F16G)
Top Applicants
Top 10 applicants by patent filings, 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