Michelle Obama’s memoir, Becoming, is on track to be the biggest-selling memoir in history, according to reports. Obama, released her book in November. It has since sold around 10 million copies, publisher Penguin Random House said Tuesday. "We believe this could be the most successful memoir in history,” Thomas Rabe, the chief executive of Bertelsmann, the parent company of Penguin Random House, said Tuesday at Bertelsmann's annual conference in Berlin. The memoir is an in-depth, personal look at Obama's life before, during and after her family's eight years in the White House.