As of 2013, Ezra and his brother David are considered influential "mega-dealers" of modern and impressionist art by the most well-known names, from Monet and Matisse to Renoir and Rothko.[citation needed] They own an inventory of between 4,000 and 4,500 works, stored in the duty-free Geneva Freeport warehouse next to the airport in Geneva, Switzerland.[citation needed] The brothers buy and sell most of their works at auction.[citation needed]