The deal is not negotiable, and the email demanding that authors opt into it warns that AI might make writers obsolete (remember, even if AI can't do your job, an AI salesman can convince Rupert Murdoch - who is insatiably horny for not paying writers - that an AI is capable of doing your job):
https://www.avclub.com/harpercollins-selling-books-to-ai-language-training
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