Generally speaking, radio dramas adapted from novels and doujinshi required the authorization of the copyright owner. This was because the act of adaptation required certain modifications to the original novel and required the use of the original novel's characters, storyline, and other content. If the radio drama was adapted without the authorization of the copyright owner, it might be regarded as an pirated work and would be pursued by law. Therefore, the producers of radio dramas adapted from novels and doujinshi needed to obtain the permission of the copyright owner of the novel and abide by relevant copyright laws and regulations during the production process. If the copyright owner objected to the adaptation, the producer would also have to bear the corresponding legal responsibility. Of course, there were also some novel copyright owners who did not pursue the issue of copyright violation for radio dramas adapted from novels, but this required specific analysis. It is recommended to consult the relevant copyright owner to obtain authorization and comply with relevant laws and regulations before adapting a novel to a radio drama.