Screenwriter Stephany Folsom has been denied a co-writing credit for Thor: Ragnarok by the Writers Guild of America. On Twitter, Folsom wrote that Marvel had agreed to give her credit for her work on the Thor sequel script. However, the WGA has regulations in place that limit the amount of writers that receive writing credit for a film.

Marvel gave me "story by"credit on THOR RAGNAROK and the writers' guild denied me the credit due to guild regulations. Are you kidding me?

— Stephany Folsom (@StephanyFolsom) September 11, 2017

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The writing duo Craig Kyle and Christopher Yost were originally announced as the writing team behind the forthcoming Marvel film. However, Eric Pearson and Stephany Folsom were later brought on to the project as additional writers. As things stand right now, Pearson has been credited for the screenplay, while Kyle and Yost also receive story credit. Folsom, however, will not.

Despite being frequent collaborators, Kyle and Yost are not a recognized writing team, so the WGA treats them as two separate creators. The Writers Guild limits a maximum of two individual writers to receive story credit, so Kyle and Yost are given that credit, and Folsom is left outside the limit.

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Marvel brought Folson aboard in December 2015 in order to polish up the film's script. She is one of the several other female writers who have been brought on by the studio to work on some of their biggest movies in recent years. Other instances include Nicole Pearlman, who wrote Guardians of the Galaxy, and Tomb Raider's Geneva Robertson-Dworet, who was recently enlisted to write Captain Marvel.

Folsom's past credits include her Black List script 1969: A Space Odyssey or How Kubrick Learned to Stop Worrying and Land on the Moon. She also has a writing credit for The Princess of North Sudan, which is currently in development at Disney.

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The WGA made their initial decision earlier in the summer, but Folsom has been fighting for credit ever since. According to her comments on Twitter, she plans to appeal this decision in order to gain credit for her work. She also stated that Marvel has supported her throughout.

Arriving November 3, director Taika Waititi’s Thor: Ragnarok stars Chris Hemsworth as Thor, Tom Hiddleston as Loki, Cate Blanchett as Hela, Idris Elba as Heimdall, Jeff Goldblum as Grandmaster, Tessa Thompson as Valkyrie, Karl Urban as Skurge, Mark Ruffalo as Bruce Banner/the Hulk and Anthony Hopkins as Odin.