Finland's Nokia said on Wednesday it had sued Apple, accusing the iPhone maker of violating 32 technology patents.
Apple sued Acacia Research and Conversant Intellectual Property Management on Tuesday, accusing them of colluding with Nokia to extract and extort exorbitant revenues unfairly and anticompetitively from Apple.
Nokia's lawsuits, filed in courts in Dusseldorf, Mannheim, and Munich, Germany and the U.S. District Court for the Eastern District of Texas, cover patents for displays, user interfaces, software, antennas, chipsets, and video coding.
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"Since agreeing a license covering some patents from the Nokia Technologies portfolio in 2011, Apple has declined subsequent offers made by Nokia to license other of its patented inventions which are used by many of Apple's products," Nokia (nok) said in a statement.
Apple (aapl) and Acacia did not immediately respond to requests for comment.