B28 WORKING CEMENT, CLAY, OR STONE
Description
Class B28 covers machinery and processes for processing and working cement, clay, and stone materials. This includes equipment for crushing, grinding, mixing, shaping, and treating these raw materials and their products, such as concrete, bricks, tiles, and dimension stone. The class encompasses both wet and dry processing methods, as well as auxiliary operations like screening, drying, and quality control during production. It excludes finished construction work and the design of structures themselves, which fall under other sections of the IPC.
Filing statistics
CPC B28 recorded 104,088 patent applications worldwide between 2013 and 2023, summed across its 3 subclasses. Annual filings grew from 4,290 in 2013 to 9,570 in 2023 (+123%), peaking at 14,513 applications in 2020. The most active applicants in class B28 are DISCO CORPORATION (1,471 applications), HILTI (575 applications) and CORNING (544 applications).
Source: EPO PATSTAT, worldwide filings
3 direct subcodes
Child Classifications
Navigate with arrow keys, Enter to open
- B28B SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER (foundry moulding B22C; working stone or stone-like material B28D; shaping of substances in a plastic state, in general B29C; making layered products not composed wholly of these substances B32B)
- B28C PREPARING CLAY; PRODUCING MIXTURES CONTAINING CLAY OR CEMENTITIOUS MATERIAL, e.g. PLASTER (preparing material for foundry moulds B22C5/00)
- B28D WORKING STONE OR STONE-LIKE MATERIALS
Top Applicants
Top 10 applicants by patent filings, 2013–2023, worldwide · Source: EPO PATSTAT
- DISCO CORPORATION JP 1,471
- HILTI LI 575
- CORNING US 544
- MITSUBOSHI DIAMOND INDUSTRIAL COMPANY JP 518
- UNITED STATES GYPSUM COMPANY US 485
- DISCO ABRASIVE SYSTEM 459
- GE (GENERAL ELECTRIC COMPANY) US 454
- MITSUBOSHI DIAMOND INDUSTRIAL COMPANY 439
- DISCO CORPORATION 403
- NGK INSULATORS JP 308