Apple has lost a ruling by a US trade panel in a patent dispute with its rival Samsung.
The International Trade Commission (ITC) ruled that Apple infringed a Samsung patent, which could mean some older models of the iPad and iPhone are banned from sale in the US.
The patent relates to 3G wireless technology and the ability to transmit multiple services correctly and at the same time. Apple said it plans to appeal.
The ruling could also be reversed by a US presidential order within 60 days.
The ruling overturned an earlier decision by ITC Judge James Gildea, who said in September that Apple did not violate the patents at issue in the case, which was filed nearly three years ago.
"We believe the ITC’s final determination has confirmed Apple’s history of free-riding on Samsung’s technological innovations," a Samsung statement said.
The ITC ordered a halt on all imports and sales on AT&T-sold models of the iPhone 4, iPhone 3, iPhone 3GS as well as the iPad 3G and iPad 2 3G. Some of those devices are no longer on sale in the US.
Import-ban orders from the ITC are subject to review by US President Barack Obama. Mr Obama could overturn it, though it is rare for that to happen.
Apple is free to continue selling the models involved during the 60-day review period.