V 104 Falke was a German-built cargo ship which was converted into an auxiliary warship for the Kriegsmarine as a Vorpostenboot and then Sperrbrecher.

Renamed Düsseldorf,[4] it was captured off the coast of Norway by the Royal Navy Q-ship HMS Tay and Tyne between 19 and 24 February 1918 whist on a voyage from Tromsø, Norway to Stettin with a cargo of iron ore.[5][6][7][8] It was seized by the British government and was renamed Poldorf.

[2] Due to the ship being captured in neutral waters, a legal dispute with Norway came before the British Prize Court in July 1920.

Falke was transferred to Argo Reederei AG in 1934,[4] in which year the Code Letters DOBY were allocated.

On 1 October 1940, the 1st flotilla was disbanded and Falke was designated as a Sperrbrecher, or mine clearing ship.