The Black Hand

Wikipedia holds stories about the following Black Hands:

'Mano Negra', which was a proto-Italian mafia created in America by the Italian immigrants.

'Crna Ruka', the Serbian military society that started World War I by assassinating Archduke Franz Ferdinand.

'La Mano Negra', a secret Spanish anarchist organisation, possibly invented by the government as an excuse for killing off some inconvenient people in XIXth century.

Has this hand print got anything to do with any of them...? Or was it created simply because a shop to the right was just recently repainted black and someone possibly leaned against it and then the creative Marchmont air took over?