NTP, a U.S. patent-holding company, has filed suit against Apple, Google, HTC Corp., LG Electronics, Microsoft and Motorola accusing the technology giants of infringing its email patents in mobile phones.
NTP, in the suits filed on Thursday in the U.S. District Court for the Eastern District of Virginia, accused the companies of infringing eight patents it holds for wireless email.
"Use of NTP's intellectual property without a license is just plain unfair to NTP and its licensees," NTP co-founder Donald Stout said in a statement.
He said legal action "is necessary to ensure that those companies who are infringing NTP's patents will be required to pay a licensing fee."
NTP describes its other co-founder, the late Thomas Campana, as the "inventor of wireless email."
In 2006, Canada's Research in Motion, maker of the Blackberry, agreed to pay $612 million to NTP to settle patent infringement claims and to license NTP-patented technology.
NTP has separately filed suits against mobile phone manufacturer Palm and several telecom companies accusing them of patent infringement. Those cases, launched in 2006, are ongoing.
NTP has a licensing agreement with Nokia, and the Finnish mobile phone giant was not named in Thursday's suits.
Patent lawsuits are a regular occurrence among technology giants and Apple is currently being sued by Nokia for patent infringement. Apple has fired back a countersuit against Nokia.
Taiwan's HTC and Apple are also currently suing each other over patent claims.
Copyright Agence-France Presse, 2010