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 Wonderful Wizard of Oz (1910 film)
The Wonderful Wizard of Oz is a 1910 American silent fantasy film and the earliest surviving film version of L. Frank Baum's 1900 novel "The Wonderful Wizard of Oz", made by the Selig Polyscope Company without Baum's direct input. It was created to fulfill a contractual obligation associated with Baum's personal bankruptcy caused by "The Fairylogue and Radio-Plays", from which it was once thought to have been derived. It was partly based on the 1902 stage musical "The Wizard of Oz", though much of the film deals with the Wicked Witch of the West, who does not appear in the musical.