Superman has fascinated scholars, with cultural theorists, commentators, and critics alike exploring the character's impact and role in the United States and the rest of the world. Umberto Eco discussed the mythic qualities of the character in the early 1960s, and Larry Niven has pondered the implications of a sexual relationship the character might enjoy with Lois Lane.[11] The character's ownership has often been the subject of dispute, with Siegel and Shuster twice suing for the return of legal ownership. The copyright is again currently in dispute, with changes in copyright law allowing Siegel's wife and daughter to claim a share of the copyright, a move DC parent company Warner Bros. disputes.