NUCLEAR EXPLOSIVES; APPLICATIONS THEREOF

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

IPC subclass G21J recorded 58 patent applications worldwide between 2013 and 2023. Annual filings grew from 2 in 2013 to 2 in 2023 (+0%), peaking at 17 applications in 2019. The most active applicants in class G21 are CHINA GENERAL NUCLEAR POWER CORPORATION (2,364 applications), CGN POWER COMPANY (1,899 applications) and CHINA NUCLEAR POWER ENGINEERING COMPANY (1,870 applications).

Source: EPO PATSTAT, worldwide filings

Additional Content

Uncontrollable reaction uncontrollable reactions Any fission or fusion reaction where event initiators (e.g. neutrons in the fission process) are produced in a number greater than required to sustain a chain reaction and where there is no mechanism to selectively moderate the reaction, e.g. a fission reactor where the operator has simply opted not to moderate or has failed to moderate the reaction is not a nuclear explosive device in the context of this subclass.