Nokia, one of the world's leading mobile phone makers, said Wednesday it had filed patent infringement lawsuits against mobile phone and electronics groups HTC, RIM and ViewSonic in the United States and Germany.
"Though we'd prefer to avoid litigation, Nokia had to file these actions to end the unauthorised use of our proprietary innovations and technologies, which have not been widely licensed," Nokia said in a statement.
The lawsuits concerned a total of 45 patents.
The Finnish company said its actions included a complaint to the US International Trade Commission against Taiwan's leading smartphone maker HTC, and suits against HTC and US electronics group ViewSonic in the US Federal District Court of Delaware.
It was also filing suits against HTC and Canadian BlackBerry maker RIM in the Regional Court in Dusseldorf, Germany, and against all three companies in the Regional Courts in Mannheim and Munich, Germany.
Nokia said the innovations protected by its patents "are being used by the companies to enable hardware capabilities such as dual function antennas, power management and multimode radios."
They also "enhance software features including application stores, multitasking, navigation, conversational message display, dynamic menus, data encryption and retrieval of email attachments on a mobile device," it said.
"Many of these inventions are fundamental to Nokia products," Nokia's chief legal officer Louise Pentland said.
Nokia has been losing market share as it struggles to compete in the smartphone sector. It is currently undergoing a major restructuring, phasing out its Symbian smartphones in favour of a partnership with Microsoft.
It announced disastrous first quarter results in April, posting a net loss of 929 million euros ($1.2 billion) as sales slumped 30 percent year-on-year.
And this week technology research firm International Data Corporation (IDC) said Nokia had lost its top mobile phone maker ranking to Samsung, which along with Apple is already well ahead of Nokia in the lucrative smart phone sector.
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