Nokia, the world's biggest mobile phone maker, has said that it is suing its US rival Apple for infringing patents on mobile phone technology for the iPhone.
Nokia says it has not been compensated for its technology, and accused Apple of "trying to get a free ride on the back of Nokia's innovation".
The ten alleged patent infringements involve wireless data, speech coding, security, and encryption.
Apple's shares dipped after news of the action broke.
Finland's Nokia said that it had agreements with about 40 firms - including most mobile phone handset makers - allowing them to use the firm's innovation, but that Apple had not done so.
"The basic principle in the mobile industry is that those companies who contribute in technology development to establish standards create intellectual property, which others then need to compensate for," said Ilkka Rahnasto, Vice President, Legal &
Intellectual Property at Nokia.
"Apple is also expected to follow this principle."
He added that during the last two decades, Nokia had invested approximately 40bn euros (£36.2bn; $60bn) on research and development.
The action has been filed in the Federal District Court in Delaware.
