Apple is applying for a patent on a technique that would take the guesswork out of listening by smoothing out all the quirks.

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The group has filed a patent on the technique.

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Yep, if you use a process or technique that is covered by some patent that has already been awarded then the patent holder could come after you for infringement.

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As is typical with patents, the patent claims appear to overlap in places, with both companies saying they have patents on the technique of boosting chemical pathways in yeast that produce isobutanol.

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The Supreme Court did uphold a patent on a software-controlled rubber-curing machine in 1981, but its ruling emphasized that this was because the patent covered a physical machine that happened to have a software component, rather than claiming a software technique by itself.

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