InterDigital loses another round in patent fight

By Diane Bartz

WASHINGTON (Reuters) - InterDigital Inc, a patent licensing firm, lost an infringement fight on Wednesday as a U.S. appeals court ruled that wireless phones made by Nokia, since purchased by Microsoft, and ZTE Corp do not infringe on InterDigital patents.

InterDigital's share price was down 3.4 percent for the day, at $49.14.

The U.S. Court of Appeals for the Federal Circuit upheld a decision by the International Trade Commission, which found the patents were not infringed.

The appeal involved five patents. Four help the cell phone use less power and one allows the device to use various networks to transfer data.

The Federal Circuit also upheld the ITC's decision to declare the fifth patent invalid because it is obvious, which means it cannot be infringed.

Microsoft was pleased with the decision, said spokesman David Cuddy.

InterDigital said it was disappointed by the decision but would push on with other litigation that it already has under way.

"We remain very confident in the strength of our portfolio, and in our ability to continue to grow our licensing program," William J. Merritt, chief executive of InterDigital, said in a statement.

Separately, InterDigital sued ZTE Corp and Microsoft's Nokia handset business in a district court in Delaware using different patents. It won against ZTE in October but the Microsoft trial has not yet begun.

Companies frequently sue at the ITC to win an injunction against infringement and in district court to win damages.

The case at the International Trade Commission is InterDigital Communications v. Nokia Corp and ZTE Corp and is No. 337-868. At the Federal Circuit, it was No. 2014-1176.

(Reporting by Diane Bartz; Editing by Chris Reese)