Prince Harry's Memoir Updates | Prince Harry’s Spare Becomes UK’s Fastest Selling Non-fiction BookPrince Harry’s memoir, titled Spare, has become the UK’s fastest selling non-fiction book ever. The Duke of Sussex’s autobiography was officially released on January 10. Its publishers said on Tuesday that they had sold 400,000 copies so far across hardback, e-book and audio formats."We always knew this book would fly but it is exceeding even our most bullish expectations," Transworld Penguin Random House Managing Director Larry Finlay said in a statement. "As far as we know, the only books to have sold more in their first day are those starring the other Harry (Potter),” he added.