A group representing 400 musicians and their managers is demanding greater regulation of the secondary ticketing market, claiming that a partnership between Madonna and ticket resale site Viagogo suggests the industry cannot regulate itself.

The Resale Rights Society, whose members includes the management of Robbie Williams, Radiohead and the Arctic Monkeys, said that Madonna’s partnership with Viagogo as the “official” ticket resale website for her “Sticky & Sweet” tour did not protect consumers or help artists.