4. Rothko Vandalism at the Tate Modern

Date: October 7, 2012

Last October, a vandal by the name of Vladimir Umanets defaced Mark Rothko's 1959 Black on Maroon painting at the Tate Modern in London. He wrote "Vladimir Umanets '12 / A Potential Piece of Yellowism" on it and calmly walked away without getting caught by security. Bystanders tweeted the image above, causing the event to go viral online. The painting's estimated worth is around $86.7 million. Days later, he was arrested by the Metropolitan Police.