While known for mocking the powerful as they strive to become objects of mass appeal, many of Banksy’s illicit street artworks ultimately belong to private landlords, not the public. After a late-night visit from the anonymous artist, property owners often wake up to find they’ve won the Banksy lottery: He has “vandalized” one of their buildings by gifting it a work by a world-famous artist. And then it is up to them to decide the work’s fate.