(AP) -- Apple Inc. is suing cell phone maker Nokia Corp. for patent infringement, a countermove to Nokia's earlier suit against technologies used in Apple's iPhone.
Apple's lawsuit claims Nokia is infringing on 13 of Apple's patents, and says the Finland-based company chose to "copy the iPhone," especially its user interface, to make up for its declining share of the high-end phone market.
Nokia's lawsuit, filed in October, claims that Cupertino, Calif.-based Apple infringes on 10 of its patents covering both phone calls and Wi-Fi access.
The patents Apple alleges Nokia is infringing deal with, among other things: connecting a phone to a computer, teleconferencing, menus on a touch screen, power conservation in chips, and "pattern and color abstraction in a graphical user interface."
Nokia representatives could not immediately be reached for comment Friday morning.
Apple said Nokia fell behind in the smart phone market because it chose to focus on old-fashioned cell phones with conventional user interfaces at a time when "smart" phones were growing increasingly popular.
Countersuits are a staple of patent litigation, which often ends in cross-licensing agreements. Nokia said in October that 40 phone manufacturers - but not Apple - have licensed the patents in its lawsuit.
Both suits were filed in federal court in Delaware.
U.S.-traded shares of Nokia rose 27 cents, or 2.2 percent, to $12.83 in morning trading, and Apple's shares slid 62 cents to $195.81.
©2009 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
Explore further: Why the Sony hack isn't big news in Japan