Apple has been ordered to pay more than $500 million in a long-fought patent dispute against the University of Wisconsin-Madison’s patent-licensing division.
U.S. District Court Judge William Conley on Tuesday ruled that Apple should pay $506 million in damages for allegedly infringing a patent owned by the Wisconsin Alumni Research Foundation (WARF). The judge, whose ruling was earlier reported on by Reuters, added $272 million to a previous $234 million damages tally because the iPhone maker continued to infringe the patent, according to the judge.
The patent is question relates to a technology called a “predictor circuit.” The patent, which was awarded to the University in 1998, describes how the circuit can improve a processor’s performance inside a device. The “predictor” element to the technology allows the processor to anticipate a user’s commands to the system before they’re made, so it can respond more quickly.
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WARF sued Apple (AAPL) in 2014, alleging the company used the technology in some of its iPhones. In 2015, a jury awarded WARF $234 million in damages after jurors determined Apple was violating the University’s patent. Apple, which denied the allegations, has said that the patent is invalid and shouldn’t have been awarded. However, the U.S. Patent and Trademark Office (USPTO) has rebuffed the iPhone maker’s request to review the patent’s validity.
According to Reuters, Judge Conley added $272 million to the damages award after determining that Apple continued to use the technology in iPhones through December 2016.
Apple did not respond to a Fortune request for comment on the judge’s decision.