The technology used by Vonage to deliver voice-mail service to its 1.6 million VoIP (Voice over Internet Protocol) telephony customers infringes on another company's patent, according to a lawsuit filed Monday.
Klausner Technologies has asked a federal court in the eastern district of Texas to fine Vonage $180 million in damages and royalties for the patent infringement.
Klausner, a privately owned company that controls 25 patents for VoIP voice-mail technology, already collects licensing fees from Time Warner for its use of this technology in its AOL Voicemail and VoIP voice-mail services.
Klausner asked Vonage, of Holmdel, New Jersey, to sign a similar agreement in January, but Vonage's only response has been a request for more time, Klausner claims.
Vonage did not reply to requests for comment on this story.
This is the second patent infringement suit to hit Vonage in recent weeks. In June, telecommunications giant Verizon Communications leveled a patent infringement lawsuit claiming that Vonage relies on seven of Verizon's patented technologies to make its VoIP system work.
Vonage, a relatively small company that went public in May, is fighting back with its own lawsuit. Also Monday, the company announced that it had acquired three VoIP patents from Digital Packet Licensing.
The new patents are unrelated to voice mail; they concern the compression of packetized digital signals. But they allow Vonage to control license agreements with competitors like Motorola, Time Warner, and Qwest Communications, and to continue a federal patent infringement lawsuit against two other competitors, Sprint Communications and Verizon.