Apple has been found guilty of infringing a 17-year old patent owned by the University of Wisconsin, and could be facing huge damages as a result.

The patent in question covers processor efficiency, and Apple is said to have used the technology to develop the A7, A8 and A8X processing chips found in most iOS devices of the last few years.

Apple of course denied all claims, but have been found liable for infringement of all six patent claims granted to university professors way back in 1998.

Apple could be made to pay a maximum fine of $862.4 million in damages depending on the outcome of the next stage of the lawsuit. The University of Wisconsin has also filed a secondary lawsuit concerning the newer A9 chip, which could mean we see the drama drag out indefinitely.

Of course, Apple has been fighting Samsung back-and-forth over similar charges for years now so we wouldn’t expect this to be wrapped up any time soon.

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