Nortel Networks is suing Vonage, claiming that Vonage violated nine patents related to Internet phone services and related features, such as 911 and 411 calling and click-to-call. The action is a counter-suit.
In 2004, Digital Packet Licensing (DPL) sued Nortel for infringement of three of its patents. Last year, Vonage purchased those three patents from DPL. After acquiring the patents, Vonage decided to continue the suit against Nortel.