(Reuters) – A U.S. judge has ordered a new trial to determine how much Samsung Electronics Co (005930.KS) should pay Apple Inc (AAPL.O) for copying the look of the iPhone.

U.S. District Judge Lucy Koh in San Jose, California issued an order late on Sunday, 10 months after the U.S. Supreme Court set aside a $399 million award against Samsung for mimicking the iPhone’s look for its Galaxy and other devices.

The Supreme Court said damages could be based only on parts of a device that may have infringed patents, not necessarily the entire device.

Koh said the jury instructions at the Apple-Samsung trial “did not accurately reflect the law” and may have prejudiced Samsung by preventing jurors from considering whether any infringement covered “something other than the entire phone.”

The $399 million is part of a $548 million payment that Samsung made to Apple in December 2015.

Apple had argued that no new trial was warranted, and that the $399 million award should be confirmed. It did not immediately respond on Monday to requests for comment.

Samsung, in a statement, said it welcomed Koh’s order.