
In the case of Black Swan and True Grit, they have both been excluded because they exist as "scores diluted by the use of tracked themes or other pre-existing music." Black Swan is adapted from Tchaikovsky's Swan Lake, and no matter how much creativity and beauty his score brought to the film, it's simply not "original" enough. The same can be said for True Grit which apparently bases most of its music on 19th century hymns and is therefore not sufficiently "original" as well. On the other end of the spectrum, apparently The King's Speech, which raised concerns because of prominent unoriginal classical-music excerpts, has been deemed eligible for the awards.
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