In response to Nokia's own claims of copyright violation, Apple on Friday accused the largest handset maker in the world of copying some of the technology inside the iPhone.
In a suit filed in U.S. District Court for the District of Delaware (PDF), Apple says Nokia is infringing 13 of its patents.
"Other companies must compete with us by inventing their own technologies, not just by stealing ours," Bruce Sewell, Apple's general counsel, said in a statement Friday.
Nokia issued this response: "We are aware that Apple has provided its response to Nokia Delaware Suit, which was due December 14th. We will study the details of the claim and respond in due course."
Apple's filing is a response to Nokia's October suit against Apple over 10 patents the Finnish phone maker says it owns related to wireless handsets. Apple is one of a few companies--Nokia wouldn't expand on who the others might be--that is not licensing Nokia's 10 patents. Nokia says that for any phone to run on a GSM, 3G, or Wi-Fi network, it would have to license one of its patents.
In its countersuit, Apple denies Nokia's claims of copyright violation, saying that the licenses Nokia insists Apple and other smartphone makers pay are "unfair, unreasonable, and discriminatory" and "non-essential" to the iPhone. Apple is also asking the court to dismiss Nokia's suit, and goes so far as to accuse Nokia of borrowing some of Apple's intellectual property because it was losing market share.
Apple says Nokia is in violation of a range of patents, from real-time signal processing methods to list scrolling and document translation, scaling, and rotation on a touch-screen display, and is asking the court for monetary damages, and legal fees.
This story was updated on 12/12/09 with response from Nokia.