Copyright status of The Wizard of Oz and related works in the United States
"The Wonderful Wizard of Oz" was published in 1900, and was the first to enter the public domain in "1956". This allowed Reilly & Lee, the publisher of all the other Oz books (as well as Baum's other books) to issue their own edition of "The Wizard of Oz", which had previously been published by George M. Hill Company and later by the Bobbs Merill Company after Hill went bankrupt..
The International Wizard of Oz Club
The club has published many of Baum's rarer books, including "Animal Fairy Tales", "Aunt Jane's Nieces", and "Twinkle and Chubbins". It published two Oz books by Ruth Plumly Thompson and one each by Rachel Cosgrove and the team of Eloise Jarvis McGraw and Lauren Lynn McGraw. In 2000, it put out its first new Oz book not linked to the original series: Gina Wickwar's "The Hidden Prince of Oz", with illustrations by Anna-Maria Cool. A Wickwar/Cool sequel followed in 2007, "Toto of Oz." That same year it published "The Collected Short Stories of L. Frank Baum." In addition, the Club has published a set of color-printed maps of The Marvelous Land of Oz and Countries Surrounding the Land of Oz, as well as new editions of short stories by L. Frank Baum and Ruth Plumly Thompson. Its best-selling publication is "Bibliographia Oziana" by Douglas G. Greene and Peter E. Hanff, which provides bibliographical descriptions of the original Oz series.