Balanced flues (combining air supply and flue gas exhaust)

Filing statistics

CPC F23J 2211/10 belongs to the parent subclass F23J, which recorded 23,943 patent applications worldwide between 2013 and 2023. Annual filings grew from 1,318 in 2013 to 2,351 in 2023 (+78%), peaking at 3,207 applications in 2020. The most active applicants in class F23 are GE (GENERAL ELECTRIC COMPANY) (2,581 applications), UNITED TECHNOLOGIES CORPORATION (UTC) (1,180 applications) and SIEMENS (1,157 applications).

Source: EPO PATSTAT, worldwide filings