In a patent that describes a device and improved method for error detection in data transmission systems, a dependent claim recited a specific implementation of varying the way check data is generated that improves the ability of prior art detection systems. Specifically, dependent claims 2-4 required that a "varying device" "modify the permutation in time." This improvement was akin to the type of non-abstract improvement the Court found to be patent eligible under 35 USC 101.
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