NUCLEAR EXPLOSIVES; APPLICATIONS THEREOF (electric or magnetic analogue computers, e.g. simulators, for nuclear physics G06G7/54)

Description

G21J covers nuclear explosive devices and their practical applications. This includes designs for nuclear weapons, thermonuclear devices, and related triggering or detonation mechanisms. The classification also encompasses peaceful applications of nuclear explosions, such as industrial excavation, seismic research, or mineral extraction where controlled nuclear detonation is employed. Related classified research on nuclear weapon design itself typically falls within national security restrictions rather than patent literature.

Filing statistics

CPC subclass G21J recorded 43 patent applications worldwide between 2013 and 2023. Annual filings declined from 3 in 2014 to 2 in 2023 (-33%), peaking at 7 applications in 2016. The most active applicants in class G21 are CHINA GENERAL NUCLEAR POWER CORPORATION (1,383 applications), WESTINGHOUSE ELECTRIC CORPORATION (1,347 applications) and KOREA ATOMIC ENERGY RESEARCH INSTITUTE (1,303 applications).

Source: EPO PATSTAT, worldwide filings