Who Gets the Royalties for Hitler's Book?

Adolf Hitler’s book Mein Kampf entered the public domain at the beginning of 2016, because Hitler’s been dead for 70 years. That's a long time. Who was profiting from the book’s publication all those years? And who will profit now that anyone can use it? And why would anyone want to?

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According to Simon from Today I Found Out, Hitler himself made a boatload of money from the volume. After his death, the financial arrangements regarding Mein Kempf got more complicated. Read more about it at Today I Found Out.