Even if the artists don’t own the boards they painted on, shopkeepers don’t necessarily have the right to chop up the murals. The Visual Artists Rights Act (VARA) that was passed in 1990 gives artists rights to protect their work. It is intended to prevent the intentional destruction, distortion, or mutilation of works of art. Under the law, artists have the right to claim their work and must be given 90 days’ notice to take it down before it can be destroyed.
Source: Protest art leaves the streets