A company that holds patents relating to a 'visual voicemail' system is suing Apple and a host of telecoms companies for hundreds of millions of dollars.
The lawsuit was filed by Klausner Technologies in the US Court for the Eastern District of Texas, and asks for $360m from Apple and AT&T.
New York-based Klausner Technologies claims that the patent infringements concern internet voicemail services.
"The iPhone violates Klausner's intellectual property rights by allowing the user to selectively retrieve voice messages via the iPhone's inbox display," said the company in an official statement.
Klausner Technologies sued AOL for $200m in 2005 over its voice platform technology, eventually settling the case and licensing it to AOL.
Vonage settled a similar case in October this year over its Voicemail Plus, when Klausner granted Vonage a patent license for an undisclosed sum.
"We have litigated this patent successfully on two prior occasions," said Greg Dovel, counsel for Klausner Technologies at law firm Dovel & Luner.
"With the signing of each new licensee, we continue to receive further confirmation of the strength of our visual voicemail patents."
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