JK Rowling's Harry Potter chair is going up for auction. Rowling, who wrote Harry Potter and the Philosopher's Stone and Harry Potter and the Chamber of Secrets is offering the chair on April 6, 2016 as part of the Rare Books Signature Auction. Harry Potter is one of the best-selling series of novels for young adults ever written, and has turned into one of the largest film franchises of all time. Harry Potter even has spinoffs, a stage play, and its own theme park. Fantastic Beasts and Where to Find Them, a new film set in the world of Harry Potter, will kick off a new trilogy later this year.