Leonardo da Vinci painted the Mona Lisa using natural proportions and symmetry techniques. The painting was stolen from the Louvre in 1911 but recovered after two years. There is debate around whether da Vinci painted an initial nude version, as an expert recently claimed da Vinci painted a nude Mona Lisa. The painting has been attacked over the years, with an incident in 2009 where a woman threw a teacup at it.