Floating armoury

Being in possession of military-grade weapons in most jurisdictions is prohibited or highly controlled. In the early twenty-first century piracy in international waters is a serious problem. In response, services that supply weapons on the high seas, often referred to as floating armouries, were implemented. These armouries provide transfer services to private military and security companies (PMSCs); the controlled weapons are available in international waters, but never enter waters under the jurisdiction of a state where they would be illegal—they are delivered by an armoury to a client vessel, and returned, in international waters. The operations of MNG Maritime, a company supplying these services, are authorised by specifically issued UK Government trade control licences covering floating armoury services. It provides offshore storage facilities for weapons used by anti-piracy guards protecting vessels traversing the part of the Indian Ocean known as the "High Risk Area", infested by pirates based in Somalia and other places, so that the weapons do not need to be carried into territorial waters, where being in possession of weapons would be illegal. US company AdvanFort supplies similar services.

An older use of the term mainly in the early twentieth century refers to ships no longer suitable for their original purpose, converted to use as armouries permanently located at a port (sometimes used also as training vessels); e.g. USS Briarcliff (IX-3) in 1922, USS Illinois (BB-7) in 1924, and USS Sturgeon Bay (IX-27) in 1928.

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