Legal disputes over the Harry Potter series October 2007, Warner Bros. and Rowling sued Michigan-based publishing firm RDR Books to block the publication of a 400-page book version of the Harry Potter Lexicon, an online reference guide to her work. Rowling, who previously had a good relationship with Lexicon owner Steve Vander Ark, reiterated on her website that she plans to write a "Harry Potter" encyclopedia, and that the publication of a similar book before her own would hurt the proceeds of the official encyclopedia, which she plans to give to charity. A judge later barred publication of the book in any form until the case was
Harry Potter her publishers to adopt a more gender-neutral pen name in order to appeal to the male members of this age group, fearing that they would not be interested in reading a novel they knew to be written by a woman. She elected to use J. K. Rowling (Joanne Kathleen Rowling), using her grandmother's name as her second name because she has no middle name. "Harry Potter and the Philosopher's Stone" was published by Bloomsbury, the publisher of all "Harry Potter" books in the United Kingdom, on 26 June 1997. It was released in the United States on 1 September 1998