The appeals court also revived a patent claim Motorola Mobility had made against Apple but ruled Motorola could not seek a sales ban of its own.

Apple and companies that make phones using Google's Android software have filed dozens of such lawsuits against each other around the world to protect their technology. Apple, in particular, argues that Android phones that use Google software copy its iPhones.

In litigation between technology companies that boast multi-billion dollar margins, court-ordered sales bans are seen as a far more serious threat than monetary damages. Despite years of court challenges to Android, Apple has not been able to win a crippling injunction.

The U.S. Court of Appeals for the Federal Circuit had been hearing two cases - one in which Apple accused Motorola Mobility, which has since been bought by Google, of infringing its patents. Motorola, in turn, accused Apple of infringing three patents, including one that is essential to ensuring smartphones are interoperable.

The cases were consolidated at the U.S. District Court for the Northern District of Illinois. Judge Richard Posner, who took the case, dismissed it in 2012 before trial, saying that neither company had sufficient evidence to prove its case.

The appeals court considered six patents in the two cases - three belonging to Apple and three to Motorola Mobility. The two companies had appealed a variety of issues, ranging from the definitions of some patents to whether money damages were sufficient for infringement or if sales bans should be put on infringing products.

Posner had ruled an injunction barring the sale of Motorola phones would harm consumers. He also had ruled that even if infringement occurred, Apple could not sue because it could not prove it had been hurt by the infringement. But the appeals court decided Posner defined one of Apple's patents too narrowly and ordered him to reconsider Apple's request for an injunction.

The appeals court affirmed the lower court's decisions on two Motorola Mobility patents. But, as in the case of the Apple patent, it disagreed with the lower court's decision that Motorola Mobility would be entitled to no damages even if infringement was proven on a third patent. The appeals court said, however, that Motorola Mobility cannot request an injunction for infringement of that patent, the appeals court said.

Since the appeal began, Google announced that it was selling Motorola Mobility's handset business to Lenovo but would keep the vast majority of the patents. It is unclear if Lenovo will assume liability in the patent fights.

Apple and Google both declined to comment.

The case is at the U.S. Court of Appeals for the Federal Circuit and is Apple Inc. V. Motorola Mobility. It is case number 2012-1528, -1549.

(Reporting by Diane Bartz and Dan Levine; Editing by Doina Chiacu and Dan Grebler)

By Diane Bartz and Dan Levine

Stocks treated in this article : Apple Inc., Google Inc, Samsung Electronics Co., Ltd.