Samsung could be forced to stop selling some phones after Apple won an appeal in a US court.
The decision comes after a lawsuit first filed in 2012 in which Apple claimed Samsung was using some of its technology without proper permission.
That case was decided in May 2014 when Apple was awarded $120m (£76m) damages.
Apple appealed, saying Samsung should stop selling phones using the disputed features. Judges disagreed but this latest ruling overturns that decision.