D-Notice

Common card · No. 236756

In the United Kingdom, D-Notices, officially known since 2015 as DSMA-Notices (Defence and Security Media Advisory Notices), are official requests to news editors not to publish or broadcast items on specified subjects for reasons of national security. DSMA-Notices were originally called Defence Notices (abbreviated to D-Notice) from their inception in 1912 to 1993, and DA-Notices (Defence Advisory Notices) from 1993 until the mid-2010s. A similar D-Notice system was previously operational in Australia, but has fallen into disuse. Sweden maintained a similar "grey notice" system during World War II, as described below.

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