Nokia has stepped up its patent battle against Apple, launching yet another law suit in the US this time aimed at Apple’s iPhone and its new iPad tablet.
Nokia has filed suit against Apple in the Wisconsin district court, alleging that its iPhone and iPad 3G products infringe five Nokia patents.
The patents in question relate to “technologies for enhanced speech and data transmission” and antenna innovations that allow for more compact devices, said Nokia.
Nokia first filed suit against Apple in the Delaware federal court in October, claiming the iPhone infringed on 10 of its patents relating to GSM, UMTS and wireless LANs.
Apple is currently embroiled in a patent case against Nokia at the US International Trade Commission in which both companies are claiming breach of dozens of radio, user interface and other technologies.
That case will likely conclude with a series of cross-licenses and a financial settlement.
The latest legal twist comes as new research from IDC reveals that Apple’s smartphone market share rose to 16.1% in Q1, up from 10.9% a year ago.
Nokia’s share of smartphone shipments however remained flat at 39.3%, said IDC.