Ernest Cline’s pop culture odyssey Ready Player One is a mishmash of pretty much every famous nerdy thing ever created. Since all of those things are owned by different companies, it’s a tricky business getting them all into one movie, and not even Steven Spielberg could get Disney to give up the rights to Star Wars.

While speaking at a press conference for the movie, Spielberg admitted that he and his team tried really hard to get Luke and Han and the Millennium Falcon into the movie, but Disney wouldn’t budge. “We couldn’t get any Star Wars rights,” he said. “[We tried] very hard. They wouldn’t give up the Star Wars rights.” Disney bought Star Wars from George Lucas for $4 billion in 2012. Ben Mendelsohn, who starred in Star Wars spinoff Rogue One and also plays a villainous character in Ready Player One, joked, “You could’ve called me on that one, Steve. I built the Death Star, I’m just saying.”

Ready Player One’s licensing team was lead in part by producer Kristie Macosko Krieger, and worked for years to get as many properties as they could. “Kristie spent three years with all of the Warner Bros. legal people getting the rights to all of them,” Spielberg said. “And we couldn’t get all of them.” One big one they didn’t end up getting was Ultraman, who has a crucial role in the book that, in the movie, seems to have been replaced by the Iron Giant. Ultraman, as bad luck would have it, is locked in a legal battle of its own, co-writer Zak Penn told io9, and not even Spielberg could get either side to budge.

Still, his name has plenty of clout in Hollywood. “It’s fun to work for Steven Spielberg,” Penn said. “Seriously, [his team] should get an Oscar for licensing.”

Ready Player One opens March 29.

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