Blu, helped by a group of activists, covered over his own works with grey paint

“A week later, on March 18, an exhibition called “Street Art: Banksy & Co” was scheduled to open. The exhibition was organized by the Fondazione Carisbo, a local bank-owned foundation whose president is Fabio Roversi Monaco, the former rector of the University of Bologna, as well as the former president of BolognaFiere, a public-private partnership that organizes exhibitions. In Bologna, the name Roversi Monaco evokes power, money, and banks. The exhibition was expected to display works of art removed from walls with the stated intention of “salvaging them from demolition and preserving them from the injuries of time,” which means turning them into museum pieces, and eventually transforming them into value.”

— http://www.e-flux.com/journal/blus-iconoclasm-and-the-end-of-the-dada-century/