The rights to which famous character were sold by his creators 'DC Comics' for $130 in 1938?

Superman is a fictional superhero. The character was created by writer Jerry Siegel and artist Joe Shuster, and first appeared in 'Action Comics' #1, a comic book published on April 18, 1938. The character regularly appears in comic books published by 'DC Comics', and has been adapted to a number of radio serials, movies, and television shows.

In early January 1938, Siegel had a three-way telephone conversation with Liebowitz and an employee of McClure named Max Gaines. Gaines informed Siegel that McClure had rejected Superman, and asked if he could forward their Superman strips to Liebowitz so that Liebowitz could consider them for 'Action Comics'. Siegel agreed. Liebowitz and his colleagues were impressed by the strips, and they asked Siegel and Shuster to develop the strips into 13 pages for 'Action Comics'. Having grown tired of rejections, Siegel and Shuster accepted the offer.

Siegel and Shuster submitted their work in late February and were paid $130 (AFI $2,361) for their work ($10 per page). In early March they signed a contract (at Liebowitz's request) in which they released the copyright for Superman to 'Detective Comics, Inc'. This was normal practice in the business, and Siegel and Shuster had given away the copyrights to their previous works as well.